ATTACHMENT D
FINAL ENVIRONMENTAL IMPACT REPORT
State Clearinghouse No. 2023020497
Final Environmental Impact Report
Hughes Circuits Project
City of San Marcos
1 Civic Center Drive
San Marcos, California 92069
Contact: Chris Garcia
Prepared by:
605 Third Street
Encinitas, California 92024
Contact: Vanessa Scheidel
March 2024
Printed on 30% post-consumer recycled material.
Hughes Circuits Project Environmental Impact Report March 2024 City of San Marcos TOC-i
TABLE OF CONTENTS
Section Page No.
1 EXECUTIVE SUMMARY ................................ ................................ ................................ ............ 1-1
1.1 Project Summary ............................................................................................................ 1-1
1.2 Summary of Significant Effects And Mitigation Measures That Reduce or Avoid The Significant Effect ........................................................................................... 1-1
1.3 Areas of Concern ............................................................................................................ 1-3
1.4 Issues to be Resolved by the Decision Making Body .................................................. 1-3
1.5 Project Alternatives ........................................................................................................ 1-3
1.5.1 No Project/No Development Alternative ......................................................... 1-4
1.5.2 Reduced Development Intensity Alternative ................................................... 1-4
1.5.3 Environmentally Superior Alternative .............................................................. 1-5 2 PROJECT DESCRIPTION, LOCATION, AND ENVIRONMENTAL SETTING ................................ ... 2-1
2.1 Project Objectives .......................................................................................................... 2-1
2.2 Project Description ......................................................................................................... 2-1
2.2.1 Discretionary Actions Required of the City ...................................................... 2-2
2.2.2 Project Characteristics ...................................................................................... 2-3
2.3 Environmental Setting ................................................................................................... 2-5
2.3.1 Existing Land Uses and Setting ........................................................................ 2-5
2.3.2 Existing Land Use and Zoning Designations ................................................... 2-5
2.3.3 Regional Setting ................................................................................................ 2-6
2.3.4 Public Services .................................................................................................. 2-8
2.4 Intended Uses for EIR .................................................................................................... 2-8
2.4.1 Scope of the EIR ................................................................................................ 2-9
2.4.2 Notice of Preparation and Scoping ................................................................ 2-10
2.4.3 Draft EIR and Public Review ........................................................................... 2-10
2.4.4 Final EIR Publication and Certification .......................................................... 2-11
2.4.5 Project Approvals and Permits ............................................................... 2-212-12
2.5 Project Inconsistencies with Applicable Regional and General Plans .............. 2-222-12
2.6 List of Past, Present and Reasonably Anticipated Future Projects in the Project Area .......................................................................................................... 2-222-12 3 ENVIRONMENTAL ANALYSIS ................................ ................................ ............................... 3.1-1
3.1 Aesthetics .................................................................................................................... 3.1-1
3.1.1 Existing Conditions ......................................................................................... 3.1-1
3.1.2 Regulatory Setting ............................................................................... 3.2-143.1-4
3.1.3 Thresholds of Significance ................................................................. 3.2-243.1-6
3.1.4 Project Impact Analysis ...................................................................... 3.2-263.1-7 Table of Contents
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3.1.5 Cumulative Impact Analysis ............................................................ 3.2-353.1-10
3.1.6 Mitigation Measures ........................................................................ 3.2-353.1-11
3.1.7 Conclusion ........................................................................................ 3.2-363.1-11
3.2 Air Quality .................................................................................................................... 3.2-1
3.2.1 Existing Conditions ......................................................................................... 3.2-1
3.2.2 Regulatory Setting ........................................................................................ 3.2-14
3.2.3 Thresholds of Significance .......................................................................... 3.2-24
3.2.4 Project Impact Analysis ............................................................................... 3.2-26
3.2.5 Cumulative Impact Analysis ........................................................................ 3.2-35
3.2.6 Mitigation Measures .................................................................................... 3.2-35
3.2.7 Conclusion .................................................................................................... 3.2-36
3.3 Biological Resources................................................................................................... 3.3-1
3.3.1 Existing Conditions ......................................................................................... 3.3-2
3.3.2 Methodology ................................................................................................. 3.3-14
3.3.3 Regulatory Setting ........................................................................................ 3.3-20
3.3.4 Thresholds of Significance .......................................................................... 3.3-26
3.3.5 Project Impact Analysis ............................................................................... 3.3-27
3.3.6 Cumulative Impact Analysis ........................................................................ 3.3-35
3.3.7 Mitigation Measures .................................................................................... 3.3-37
3.3.8 Conclusion .................................................................................................... 3.3-43
3.4 Cultural Resources ...................................................................................................... 3.4-1
3.4.1 Existing Conditions ......................................................................................... 3.4-1
3.4.2 Regulatory Setting .......................................................................................... 3.4-5
3.4.3 Thresholds of Significance ............................................................................ 3.4-8
3.4.4 Project Impact Analysis ................................................................................. 3.4-8
3.4.5 Cumulative Impact Analysis ............................................................... 3.4-103.4-9
3.4.6 Mitigation Measures ........................................................................ 3.4-113.4-10
3.4.7 Conclusion .................................................................................................... 3.4-16
3.5 Energy .......................................................................................................................... 3.5-1
3.5.1 Existing Conditions ......................................................................................... 3.5-1
3.5.2 Regulatory Setting .......................................................................................... 3.5-3
3.5.3 Thresholds of Significance .......................................................................... 3.5-13
3.5.4 Project Impact Analysis ............................................................................... 3.5-13
3.5.5 Cumulative Impact Analysis ........................................................................ 3.5-19
3.5.6 Mitigation Measures .................................................................................... 3.5-19
3.5.7 Conclusion .................................................................................................... 3.5-19
3.6 Geology and Soils ........................................................................................................ 3.6-1
3.6.1 Existing Conditions ......................................................................................... 3.6-2
3.6.2 Regulatory Setting .......................................................................................... 3.6-5 Table of Contents
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3.6.3 Thresholds of Significance .......................................................................... 3.6-11
3.6.4 Project Impact Analysis ............................................................................... 3.6-12
3.6.5 Cumulative Impact Analysis ........................................................................ 3.6-16
3.6.6 Mitigation Measures .................................................................................... 3.6-16
3.6.7 Conclusion .................................................................................................... 3.6-17
3.7 Greenhouse Gas Emissions ....................................................................................... 3.7-1
3.7.1 Existing Conditions ......................................................................................... 3.7-1
3.7.2 Regulatory Setting .......................................................................................... 3.7-8
3.7.3 Thresholds of Significance .......................................................................... 3.7-27
3.7.4 Project Impact Analysis ............................................................................... 3.7-28
3.7.5 Cumulative Impact Analysis ........................................................................ 3.7-34
3.7.6 Mitigation Measures .................................................................................... 3.7-35
3.7.7 Conclusion .................................................................................................... 3.7-35
3.8 Hazards and Hazardous Materials ............................................................................ 3.8-1
3.8.1 Existing Conditions ......................................................................................... 3.8-1
3.8.2 Regulatory Setting .......................................................................................... 3.8-2
3.8.3 Thresholds of Significance .......................................................................... 3.8-10
3.8.4 Project Impact Analysis ............................................................................... 3.8-11
3.8.5 Cumulative Impact Analysis ........................................................................ 3.8-15
3.8.6 Mitigation Measures .................................................................................... 3.8-15
3.8.7 Conclusion .................................................................................................... 3.8-15
3.9 Hydrology and Water Quality ...................................................................................... 3.9-1
3.9.1 Existing Conditions ......................................................................................... 3.9-2
3.9.2 Regulatory Setting .......................................................................................... 3.9-4
3.9.3 Thresholds of Significance .......................................................................... 3.9-10
3.9.4 Project Impact Analysis ............................................................................... 3.9-11
3.9.5 Cumulative Impact Analysis ........................................................................ 3.9-16
3.9.6 Mitigation Measures .................................................................................... 3.9-17
3.9.7 Conclusion .................................................................................................... 3.9-17
3.10 Land Use and Planning ............................................................................................. 3.10-1
3.10.1 Existing Conditions ....................................................................................... 3.10-1
3.10.2 Regulatory Setting ........................................................................................ 3.10-2
3.10.3 Thresholds of Significance .......................................................................... 3.10-7
3.10.4 Project Impact Analysis ............................................................................... 3.10-8
3.10.5 Cumulative Impact Analysis ..................................................................... 3.10-20
3.10.6 Mitigation Measures ................................................................................. 3.10-21
3.10.7 Conclusion ................................................................................................. 3.10-21
3.11 Noise .......................................................................................................................... 3.11-1
3.11.1 Existing Conditions ....................................................................................... 3.11-1 Table of Contents
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3.11.2 Regulatory Setting ........................................................................................ 3.11-5
3.11.3 Thresholds of Significance ....................................................................... 3.11-10
3.11.4 Project Impact Analysis ............................................................................ 3.11-11
3.11.5 Cumulative Impact Analysis ..................................................................... 3.11-17
3.11.6 Mitigation Measures ................................................................................. 3.11-18
3.11.7 Conclusion ................................................................................................. 3.11-18
3.12 Population and Housing ........................................................................................... 3.12-1
3.12.1 Existing Conditions ....................................................................................... 3.12-1
3.12.2 Regulatory Setting ........................................................................................ 3.12-2
3.12.3 Thresholds of Significance .......................................................................... 3.12-6
3.12.4 Project Impact Analysis ............................................................................... 3.12-7
3.12.5 Cumulative Impact Analysis ........................................................................ 3.12-8
3.12.6 Mitigation Measures .................................................................................... 3.12-8
3.12.7 Conclusion .................................................................................................... 3.12-9
3.13 Public Services .......................................................................................................... 3.13-1
3.13.1 Existing Conditions ....................................................................................... 3.13-1
3.13.2 Regulatory Setting ........................................................................................ 3.13-3
3.13.3 Thresholds of Significance .......................................................................... 3.13-8
3.13.4 Project Impact Analysis ............................................................................... 3.13-8
3.13.5 Cumulative Impact Analysis ..................................................................... 3.13-11
3.13.6 Mitigation Measures ................................................................................. 3.13-13
3.13.7 Conclusion ................................................................................................. 3.13-13
3.14 Recreation ................................................................................................................. 3.14-1
3.14.1 Existing Conditions ....................................................................................... 3.14-1
3.14.2 Regulatory Setting ........................................................................................ 3.14-4
3.14.3 Thresholds of Significance .......................................................................... 3.14-6
3.14.4 Project Impact Analysis ............................................................................... 3.14-7
3.14.5 Cumulative Impact Analysis ........................................................................ 3.14-7
3.14.6 Mitigation Measures .................................................................................... 3.14-8
3.14.7 Conclusion .................................................................................................... 3.14-8
3.15 Transportation ........................................................................................................... 3.15-1
3.15.1 Existing Conditions ....................................................................................... 3.15-1
3.15.2 Regulatory Setting ..................................................................................... 3.15-10
3.15.3 Thresholds of Significance ....................................................................... 3.15-15
3.15.4 Project Impact Analysis ............................................................................ 3.15-15
3.15.5 Cumulative Impact Analysis ..................................................................... 3.15-25
3.15.6 Mitigation Measures ................................................................................. 3.15-26
3.15.7 Conclusion ................................................................................................. 3.15-27 Table of Contents
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3.16 Tribal Cultural Resources ......................................................................................... 3.16-1
3.16.1 Existing Conditions ....................................................................................... 3.16-2
3.16.2 Regulatory Setting ....................................................................... 3.16-11 3.16-10
3.16.3 Thresholds of Significance ....................................................................... 3.16-13
3.16.4 Project Impact Analysis ............................................................................ 3.16-13
3.16.5 Cumulative Impact Analysis ....................................................... 3.16-15 3.16-14
3.16.6 Mitigation Measures ................................................................................. 3.16-15
3.16.7 Conclusion ................................................................................................. 3.16-15
3.17 Utilities and Service Systems ................................................................................... 3.17-1
3.17.1 Existing Conditions ....................................................................................... 3.17-2
3.17.2 Regulatory Setting ........................................................................................ 3.17-5
3.17.3 Thresholds of Significance ....................................................................... 3.17-10
3.17.4 Project Impact Analysis ............................................................................ 3.17-11
3.17.5 Cumulative Impact Analysis ..................................................................... 3.17-18
3.17.6 Mitigation Measures ................................................................................. 3.17-21
3.17.7 Conclusion ................................................................................................. 3.17-21
3.18 Wildfire ....................................................................................................................... 3.18-1
3.18.1 Existing Conditions ....................................................................................... 3.18-1
3.18.2 Regulatory Setting ........................................................................................ 3.18-4
3.18.3 Thresholds of Significance .......................................................................... 3.18-6
3.18.4 Project Impact Analysis ............................................................................... 3.18-7
3.18.5 Cumulative Impact Analysis ........................................................................ 3.18-9
3.18.6 Mitigation Measures .................................................................................... 3.18-9
3.18.7 Conclusion .................................................................................................... 3.18-9 4 ALTERNATIVES ................................ ................................ ................................ ........................ 4-1
4.1 Introduction to Alternatives ........................................................................................... 4-1
4.2 Project Objectives .......................................................................................................... 4-1
4.3 Alternatives Considered But Rejected .......................................................................... 4-2
4.3.1 Alternative Location .......................................................................................... 4-2
4.4 Project Alternatives Considered in this EIR .................................................................. 4-3
4.4.1 Description of Alternatives ............................................................................... 4-3
4.4.2 Summary of Project Impacts ............................................................................ 4-3
4.4.3 No Project/No Development Alternative ......................................................... 4-4
4.4.4 Reduced Development Intensity Alternative ................................................... 4-9
4.5 Environmentally Superior Alternative ......................................................................... 4-15 5 ENVIRONMENTAL EFFECTS FOUND NOT TO BE SIGNIFICANT ................................ ................ 5-1
5.1 Agriculture and Forestry Resources .............................................................................. 5-1
5.2 Mineral Resources ......................................................................................................... 5-1 Table of Contents
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6 OTHER CEQA CONSIDERATIONS ................................ ................................ ............................. 6-1
6.1 Significant Unavoidable Impacts .................................................................................. 6-1
6.2 Growth Inducement ....................................................................................................... 6-1
6.3 Significant Irreversible Environmental Changes .......................................................... 6-3
6.3.1 Change in Land Use that Commits Future Generations to Similar Uses ....... 6-3
6.3.2 Irreversible Damage from Environmental Accidents ...................................... 6-4
6.3.3 Large Commitment of Nonrenewable Resources ........................................... 6-4 7 REFERENCES ................................ ................................ ................................ .......................... 7-1 Chapter 1: Executive Summary .................................................................................................. 7-1 Chapter 2: Project Description ................................................................................................... 7-1 Chapter 3: Environmental Analysis ............................................................................................ 7-2 Section 3.1: Aesthetics .................................................................................................. 7-2 Section 3.2: Air Quality .................................................................................................. 7-2 Section 3.3: Biological Resources ................................................................................ 7-6 Section 3.4: Cultural Resources ................................................................................... 7-9 Section 3.5: Energy ........................................................................................................ 7-9 Section 3.6: Geology and Soils ................................................................................... 7-11 Section 3.7: Greenhouse Gas Emissions ................................................................... 7-13 Section 3.8: Hazards and Hazardous Materials ........................................................ 7-16 Section 3.9: Hydrology and Water Quality .................................................................. 7-17 Section 3.10: Land Use and Planning ........................................................................ 7-18 Section 3.11: Noise ..................................................................................................... 7-19 Section 3.12: Population and Housing ....................................................................... 7-20 Section 3.13: Public Services ..................................................................................... 7-20 Section 3.14: Recreation............................................................................................. 7-21 Section 3.15: Transportation ...................................................................................... 7-22 Section 3.16: Tribal Cultural Resources ..................................................................... 7-23 Section 3.17: Utilities and Service Systems .............................................................. 7-25 Section 3.18: Wildfire .................................................................................................. 7-27 Chapter 4: Alternatives ............................................................................................................. 7-27 Chapter 5: Effects Found Not to Be Significant ...................................................................... 7-27 Chapter 6: Other CEQA Considerations ................................................................................... 7-28 8 LIST OF PREPARERS ................................ ................................ ................................ ............... 8-1
8.1 City of San Marcos ......................................................................................................... 8-1
8.2 Dudek ............................................................................................................................. 8-1
8.3 Technical Preparers ....................................................................................................... 8-1 Table of Contents
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APPENDICES
A Notice of Preparation and Public Scoping Comments
B Air Quality and Greenhouse Gas Emissions Technical Report C Biological Resources Technical Report
D Archaeological Resources Inventory Report
E Preliminary Geotechnical Evaluation
F-1 Hydrology Study
F-2 Stormwater Quality Management Plan
G Noise and Vibration Analysis Technical Report
H Fire Response Technical Memorandum
I-1 Local Transportation Analysis
I-2 Vehicle Miles Traveled (VMT) Analysis Technical Memorandum J Water and Sewer Study
K Responses to Comments
L Mitigation Monitoring and Reporting Problem
FIGURES
2-1 Project Location ............................................................................................................. 2-292-19 2-2 Project Site and Surroundings ...................................................................................... 2-312-21 2-3 Site Plan ......................................................................................................................... 2-332-23 2-4 Existing General Plan Land Use .................................................................................... 2-352-25 2-5 Existing Zoning ............................................................................................................... 2-372-27 2-6 Cumulative Projects ....................................................................................................... 2-392-29
3.3-1 Vegetation Communities and Land Covers ....................................................................... 3.3-45
3.3-2 Special-Status Plants and Wildlife ..................................................................................... 3.3-47
3.11-1 Baseline Outdoor Ambient Sound Level Measurement Positions ................................ 3.11-19
3.11-2 Predicted Stationary Source Operations Noise – with Idling Truck .............................. 3.11-21
3.16-1 Area of Potential Effects (APE) ........................................................................................ 3.16-17
3.18-1 Fire Hazard Severity Zones ............................................................................................. 3.18-11 TABLES
1-1 Summary of Significant Environmental Impacts ....................................................................1-2 1-2 Comparison of Impacts of Project and Alternatives ...............................................................1-6 2-1 Comment Letters and Commenters ............................................................................... 2-122-1 Cumulative Projects ..................................................................................................... 2-13 2-2 Summary of Changes to the Draft EIR ........................................................................ 2-12 2-3 Cumulative Projects ..................................................................................................... 2-23 Table of Contents
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3.1-1 Aesthetics Summary of Impacts .......................................................................................... 3.1-1
3.2-1 Air Quality Summary of Impacts .......................................................................................... 3.2-1
3.2-2 San Diego Air Basin Attainment Status ............................................................................... 3.2-4
3.2-3 Local Ambient Air Quality Data ............................................................................................ 3.2-5
3.2-4 Ambient Air Quality Standards ........................................................................................... 3.2-15
3.2-5 Air Quality Significance Thresholds ................................................................................... 3.2-25
3.2-6 Estimated Maximum Daily Construction Criteria Air Pollutant Emissions - Unmitigated ..................................................................................................... 3.2-29
3.2-7 Estimated Operational Criteria Air Pollutant Emissions - Unmitigated ............................ 3.2-30
3.3-1 iological Resources Summary of Impacts ........................................................................... 3.3-1
3.3-2 Existing Vegetation Communities and Land Cover Types .................................................. 3.3-3
3.3-3 Jurisdictional Aquatic Resource Summary ........................................................................ 3.3-13
3.3-4 Schedule of Surveys ........................................................................................................... 3.3-16
3.3-5 Direct Impacts to Vegetation Communities and Land Cover Types ................................ 3.3-30
3.3-6 Impacts to Jurisdictional Aquatic Resources .................................................................... 3.3-33
3.4-1 Cultural Resources Summary of Impacts ............................................................................ 3.4-1
3.5-1 Energy Summary of Impacts ................................................................................................ 3.5-1
3.5-2 Project Construction Petroleum Demand ......................................................................... 3.5-16
3.5-3 Mobile Source Fuel Consumption – Operation ................................................................. 3.5-17
3.6-1 Geology and Soils Summary of Impacts .............................................................................. 3.6-1
3.7-1 Greenhouse Gas Emissions Summary of Impacts ............................................................. 3.7-1
3.7-2 Greenhouse Gas Emissions Sources in California ............................................................. 3.7-6
3.7-3 City of San Marcos (Year 2012) Communitywide Greenhouse Gas Emissions Inventory.............................................................................................................. 3.7-6
3.7-4 Estimated Annual Construction Greenhouse Gas Emissions - Unmitigated ................... 3.7-29
3.7-5 Estimated Annual Operational Greenhouse Gas Emissions ............................................ 3.7-29
3.8-1 Hazards and Hazardous Materials Summary of Impacts .................................................. 3.8-1
3.9-1 Hydrology and Water Quality Summary of Impacts ............................................................ 3.9-1
3.10-1 Land Use Summary of Impacts .......................................................................................... 3.10-1
3.10-2 General Plan Consistency .................................................................................................. 3.10-8
3.11-1 Noise Summary of Impacts ................................................................................................ 3.11-1
3.11-2 Measured Outdoor Ambient Sound Environment Samples ............................................. 3.11-4
3.11-3 City of San Marcos Exterior Noise Standards ................................................................... 3.11-8
3.11-4 Typical Construction Equipment Maximum Noise Levels ............................................. 3.11-12
3.11-5 Predicted Construction Noise Levels per Activity Phase ............................................... 3.11-13
3.11-6 Off-Site Roadway Traffic Noise Modeling Results ......................................................... 3.11-14
3.12-1 Population and Housing Summary of Impacts ................................................................. 3.12-1
3.12-2 Forecasted Growth for the San Diego Region and the City of San Marcos .................... 3.12-5
3.13-1 Public Services Summary of Impacts ................................................................................ 3.13-1 Table of Contents
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3.14-1 Recreation Summary of Impacts ....................................................................................... 3.14-1
3.15-1 Transportation Summary of Impacts ................................................................................. 3.15-1
3.15-2 Existing Transportation Network Characteristics.............................................................. 3.15-6
3.15-3 Peak Hour Intersection LOS Results – Existing Conditions ............................................. 3.15-8
3.15-4 Roadway Segment LOS Results – Existing Conditions..................................................... 3.15-9
3.15-5 Project Trip Generation ................................................................................................... 3.15-16
3.15-6 Roadway Segment LOS Results – Horizon Year 2050 with Project Conditions .......... 3.15-19
3.15-7 Vehicle Miles Traveled Impact Analysis ......................................................................... 3.15-23
3.16-1 Tribal Cultural Resources Summary of Impacts .............................................................. 3.16-1
3.17-1 Utilities and Service Systems Summary of Impacts ......................................................... 3.17-1
3.17-2 Metropolitan Water District of Southern California Water Demands .............................. 3.17-2
3.18-1 Wildfire Summary of Impacts ............................................................................................. 3.18-1 4-1 Comparison of Impacts of Project and Alternatives ............................................................ 4-16
Table of Contents
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Hughes Circuits Project Environmental Impact Report March 2024 City of San Marcos ACR-i
ACRONYMS AND ABBREVIATIONS
Acronym/Abbreviation Definition
AB Assembly Bill
ACC Advanced Clean Cars
ADA Americans with Disabilities Act
ATCM Airborne Toxic Control Measure
BMP best management practice
CAAQS California Ambient Air Quality Standards
CAL FIRE California Department of Forestry and Fire Protection CalEEMod California Emissions Estimator Model
CALGreen California Green Building Standards
Caltrans California Department of Transportation
CAP Climate Action Plan
CAPCOA California Air Pollution Control Officers Association CARB California Air Resources Board
CBC California Building Code
CCR California Code of Regulations
CDFW California Department of Fish and Wildlife
CEC California Energy Commission
CEQA California Environmental Quality Act
CESA California Endangered Species Act
CFC California Fire Code
CFC chlorofluorocarbon
CFGC California Fish and Game Code
CFR Code of Federal Regulations
CH4 methane
City City of San Marcos
CNEL community noise equivalent level
CNRA California Natural Resources Agency
CO carbon monoxide
CO2 carbon dioxide
CO2e carbon dioxide equivalent
County County of San Diego
CPUC California Public Utilities Commission
CRHR California Register of Historical Resources
CRPR California Rare Plant Rank
CWA Clean Water Act
dB decibel
dBA A-weighted decibel
DPM diesel particulate matter
DWR California Department of Water Resources
EIR environmental impact report
EISA Energy Independence and Security Act of 2007
EO Executive Order
Acronyms and Abbreviations
Hughes Circuits Project Environmental Impact Report March 2024 City of San Marcos ACR-ii
Acronym/Abbreviation Definition
EPA U.S. Environmental Protection Agency
EV electric vehicle
FAA Federal Aviation Administration
FEMA Federal Emergency Management Agency
FESA federal Endangered Species Act
FTA Federal Transit Administration
GHG greenhouse gas
GWP global warming potential
HCFC hydrochlorofluorocarbon
HCM Highway Capacity Manual
HFC hydrofluorocarbon
HSA Hydrographic Subarea
HVAC heating, ventilation, and air conditioning
IBC International Building Code
IFC International Fire Code
ips inches per second
ISTEA Intermodal Surface Transportation Efficiency Act of 1991 kWh kilowatt-hour
Leq equivalent noise level
LID low-impact development
LOS level of service
LTA Local Transportation Analysis
MBTA Migratory Bird Treaty Act
MGD million gallons per day
MHCP Multiple Habitat Conservation Program
MM Mitigation Measure
MMT million metric tons
MRF Meadowlark Water Reclamation Facility
MRZ Mineral Resource Zone
MS4 municipal separate storm sewer system
MT metric ton
MWD Metropolitan Water District of Southern California
N2O nitrous oxide
NAAQS National Ambient Air Quality Standards
NAHC Native American Heritage Commission
NCCP Natural Community Conservation Plan
NF3 nitrogen trifluoride
NHTSA National Highway Traffic Safety Administration
NO2 nitrogen dioxide
NOP Notice of Preparation
NOx oxides of nitrogen
NPDES National Pollutant Discharge Elimination System
O3 ozone
OHWM ordinary high-water mark
Acronyms and Abbreviations
Hughes Circuits Project Environmental Impact Report March 2024 City of San Marcos ACR-iii
Acronym/Abbreviation Definition
OSHA Occupational Safety and Health Administration
PDF Project Design Feature
PFC perfluorocarbon
PFF Public Facility Fee
PM10 particulate matter with an aerodynamic diameter less than or equal to 10 microns PM2.5 particulate matter with an aerodynamic diameter less than or equal to 2.5 microns POC point of connection
PPV peak particle velocity
PRC California Public Resources Code
project Hughes Circuits Project
PRPA Paleontological Resources Protection Act
PV photovoltaic
RAQS Regional Air Quality Strategy
RCRA Resource Conservation and Recovery Act
RFS Renewable Fuel Standard
RHNA Regional Housing Needs Assessment
RMS root-mean-square
RTP Regional Transportation Plan
RWQCB Regional Water Quality Control Board
SANDAG San Diego Association of Governments
SB Senate Bill
SCIC South Coastal Information Center
SCIC South Coastal Information Center
SCS Sustainable Community Strategy
SDAB San Diego Air Basin
SDAPCD San Diego Air Pollution Control District
SDCWA San Diego County Water Authority
SDG&E San Diego Gas & Electric
SF square feet
SF6 sulfur hexafluoride
SHMA Seismic Hazards Mapping Act
SIP State Implementation Plan
SMFD San Marcos Fire Department
SMMC San Marcos Municipal Code
SMUSD San Marcos Unified School District
SO2 sulfur dioxide
SoCalGas Southern California Gas Company
SOx sulfur oxides
SR State Route
SWPPP Storm Water Pollution Prevention Plan
SWQMP Storm Water Quality Management Plan
SWRCB State Water Resources Control Board
TAC toxic air contaminant
TCR Tribal Cultural Resource
Acronyms and Abbreviations
Hughes Circuits Project Environmental Impact Report March 2024 City of San Marcos ACR-iv
Acronym/Abbreviation Definition
TDM Transportation Demand Management
TIAG Transportation Impact Analysis Guidelines
TMDL total maximum daily load
USACE U.S. Army Corps of Engineers
USC United States Code
USFWS U.S. Fish and Wildlife Service
USGS U.S. Geological Survey
UWMP Urban Water Management Plan
VdB vibration velocity decibel
VHFHSZ Very High Fire Hazard Severity Zone
VMT vehicle miles traveled
VOC volatile organic compound
VWD Vallecitos Water District
WQIP Water Quality Improvement Plan
ZEV zero-emissions vehicle
1 Executive Summary
Hughes Circuits Project Environmental Impact Report March 2024 City of San Marcos 1-1
1 EXECUTIVE SUMMARY
1.1 PROJECT SUMMARY
The Hughes Circuits Project (project) would consist of development of a 67,410 -square-foot (SF) light industrial building on a currently vacant site, to support the expansion of the existing operations of Hughes Circuits Inc. The vacant project site is comp osed of Assessor’s Parcel Numbers 219 -223-20-00 and 219-223-22-00 and sits north of South Pacific Street on one side and east of South Pacific Street on the other; however, development would only occur within Assessor’s Parcel Number 219-223-20-00.
The 67,410 SF light industrial building includes a 56,310 SF first floor, and a 11,100 SF mezzanine.
The proposed light industrial building would include a fire control room, MPOE room, trash enclosure, outdoor amenity area, electrical room, and grade level loading dock s. The proposed light industrial building would be located at the western -most portion of the project site, and the disturbance area associated with project construction would be limited to approximately 113,877 SF or 2.6 1 acres of the 10.46-acre project site. The remaining approximately 7.85 acres within the project boundary would remain in its current condition.
Parking for the proposed building would include 72 parking spaces, including 4 electric vehicle charging stations, 9 carpool and zero emission parking stalls, 4 accessible stalls, and 1 U .S. Postal Service parking stall. Additionally, 4 short-term bicycle parking spaces and 4 long-term bicycle parking spaces would be provided. Access to the proposed building would be provided via two new driveways along S. Pacific Street, one at the northwestern boundary of the proposed building site, and the other at the s outheastern boundary of the proposed building site. Stormwater basins and associated landscaping would be incorporated along the perimeter of the proposed light industrial building.
1.2 SUMMARY OF SIGNIFICANT EFFECTS AND MITIGATION
MEASURES THAT REDUCE OR AVOID THE
SIGNIFICANT EFFECT
Table 1 -1, Summary of Significant Environmental Impacts, provides a summary of significant environmental impacts resulting from the project , mitigation measures identified to reduce and/or avoid the environmental effects , and a determination of the level of significance of each impact following implementation of the identified mitigation measures. The analysis shows that, as mitigated, all project impacts w ould be less than significant , with the exception of transportation; which would result in partially mitigated, yet significant and unavoidable impacts related to vehicle miles travelled (VMT). Detailed analyses of significant environmental effects and mitigation are provided in Chapter 3, Environmental Analysis, of this environmental impact report (EIR). 1 Executive Summary
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The mitigation measures listed in Table 1 -1 would reduce impacts related to biological resources, cultural resources, geology and soils, transportation and tribal cultural resources to below a level of significance. Impacts related to transportation would remain significant and unavoidable , after mitigation incorporated.
Table 1-1
Summary of Significant Environmental Impacts
Impact Mitigation Measures
Level of Significance
After Mitigation
Biological Resources
Impact BIO-1: Special-Status Species Implementation of MM-BIO-3 through MM-BIO-131, refer to
Section 3.3
Less than
significant
Impact BIO-2: Riparian Habitat and Sensitive
Natural Communities
Implementation of MM-BIO-1 and
MM-BIO-2, refer to Section 3.3
Less than
significant
Impact BIO-3: Jurisdictional Wetlands and
Waterways
Implementation of MM-BIO-1, MM-
BIO-2, and MM-BIO-12, refer to
Section 3.3
Less than
significant
Cultural Resources
Impact CR-1: Unknown archaeological
resources may occur on the project site, and
the project has the potential to disturb such
unidentified resources during project grading.
Implementation of MM-CR-1 through
MM-CR-3, refer to Section 3.4
Less than
significant
Impact CR-2: There is a potential for project
construction activities to disturb previously
unidentified human remains on the project
site.
Implementation of MM-CR-1 through
MM-CR-4, refer to Section 3.4
Less than
significant
Geology and Soils
Impact GEO-1: Paleontological resources may
be adversely impacted during excavation
Implementation of MM-GEO-1, refer
to Section 3.6
Less than
significant
Transportation
Impact TRA-1: The project VMT per employee
would exceed 16.07 VMT per employee (15%
below regional average) threshold.
Implementation of MM-TRA-1
throughand MM-TRA-32, refer to
Section 3.15
Significant and
unavoidable
Tribal Cultural Resources
Impact TCR-1: Impacts to previously
unidentified Tribal Cultural Resources
Implementation of MM-CR-1 through
MM-CR-4, refer to Section 3.4.6
Less than
significant
Furthermore, the project proposes implementation of Project Design Feature (PDF)-AQ-1, PDF-AQ-2, and PDF-GHG-1, outlined in Section 3.2, Air Quality, and Section 3.7, Greenhouse Gas Emissions, of this EIR, which would incorporate off-road equipment that meets the U.S. Environmental Protection Agency’s Tier 4 Final emission standards for nonroad engines over 50 horsepower, use of low volatile organic compound architectural coatings, and approximately 9,700 SF of rooftop mounted solar photovoltaic panels on site.
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1.3 AREAS OF CONCERN
A Notice of Preparation (NOP) was distributed on February 22, 2023, for a 30-day public review and comment period. Additionally, a public information meeting was held on March 9, 2023.
Public comments were received on the NOP for this EIR and reflect concern or controversy over a number of environmental issues (refer to Appendix A for the NOP and NOP comment letters). A total of 5 letters were received. Issues and concerns raised in the NOP comment letters include the following:
• Cultural and Tribal Cultural Resources: impacts to cultural resources, compliance with Assembly Bill 52
• Hazards and Hazardous Materials: public health, environmental protection, disposal of hazardous waste
• Land Use: conflicts between warehouse use and sensitive receptors • Transportation: scope of the study area, existing roadway congestion, trip generation and distribution, appropriate and adequate mitigation, means of alternative transportation, project access These concerns are addressed in Chapter 3, Environmental Analysis, of this EIR.
1.4 ISSUES TO BE RESOLVED BY THE DECISION
MAKING BODY
An EIR is an informational document intended to inform the public agency decision makers and the public of the significant effects of a project, identify possible ways to minimize the significant effects, and describe reasonable alternatives to the project.
The lead agency must respond to each significant effect identified in the EIR by making “Findings” for each significant effect. The issues to be resolved by the decision makers for the project include whether or how to mitigate the associated significant effects, including whether to implement a project alternative. The decision makers must determine whether any of the project alternatives would substantially reduce significant effects while still meeting key objectives of the project.
1.5 PROJECT ALTERNATIVES
Two alternatives are proposed to provide an understanding of how environmental effects could be reduced by varying the design and scope of the project. Table 1-2 provides a comparison of the impacts of project alternatives to the impacts of the project . The alternatives outlined below are more fully discussed in Chapter 4, Alternatives, of this EIR.
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1.5.1 No Project/No Development Alternative
Under the No Project/No Development Alternative, the project would not be implemented, and the project site would remain undeveloped. However, this no project/no development alternative does not preclude future development on site, as industrial uses would still be allowed under the current Light Industrial land use designation for the site.
The project site is currently undeveloped and supports 16 vegetation communities. These vegetation communities and land covers identified are categorized into three community subgroups: sensitive uplands, sensitive wetlands/riparian habitat, and non-sensitive uplands. Sensitive uplands within the review area consist of Diegan coastal sage scrub, Diegan coastal sage scrub -Baccharis dominated, non-native grassland-artichoke-thistle dominated, non -native grassland-broadleaf dominated, valley needle grassland, and wildflower fields. Sensitive wetlands/riparian habitats within the review area include Arundo-dominated riparian habitat, disturbed wetlands, emergent wetlands, San Diego Mesa claypan vernal pools, southern willow scrub, and Tamarisk scrub. Non -sensitive uplands consist of disturbed habitat and Eucalyptus woodland. Habitat on the project site would not be impacted under this alternative; but also may not be conserved.
Overall, this alternative would be less impactful than the project; however, it would not meet the project objectives outlined in Chapter 2, Project Description, of this EIR and would not allow for conservation of biological resources on -site. This alternative is further described in Section 4. 4.3, No Project/No Development Alternative, in Chapter 4, Alternatives, of this EIR.
1.5.2 Reduced Development Intensity Alternative
California Environmental Quality Act ( CEQA) Guidelines Section 15126.6, requires consideration of alternatives to the project that are capable of avoiding or substantially reducing any significant adverse impacts associated with the project. As discussed throughout Chapter 3, Environmental Analysis, except for significant and unavoidable transportation impacts related to VMT, the project would result in less-than-significant impacts or no impact, with and without implementation of mitigation measures.
Per the City of San Marcos (City) Transportation Impact Analysis Guidelines (City of San Marcos 2020) Table 1: Sample Small Projects, projects that are consistent with the General Plan and generate fewer than 110 daily trips using San Diego Association of Governments’ trip generation rates, would not require further VMT analysis. Under the Reduced Development Intensity Alternative, a 21,800 SF warehouse building would be developed. The substantial reduction in light industrial size from 67,410 SF under the project, to 21,800 SF under this alternative would be required to fall under the Small Project criteria (i.e. less than 110 daily trips) and avoid VMT impacts.
Similar to the project, this alternative would develop a light-industrial use consistent with the General Plan land use and zoning designation for the site. Other improvements, such as circulation, 1 Executive Summary
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landscaping and utility connections would occur as required. Off -site improvements beyond those required by mitigation measures would not occur under this alternative. The reduced development footprint area under this alternative would be made into usable open space area for employees. It is expected that the employee count under this alternative would be reduced as a result of the substantially reduced warehouse size.
The Reduced Development Intensity Alternative would potentially provide a slightly reduced level of impact in some environmental analysis areas including air quality, geology and soils, greenhouse gases and transportation. However, mitigation measures would still be required to mitigate impacts to biological resources, cultural resources, and tribal cultural resources.
Overall, this alternative would be less impactful than the project, and would meet most of the project objectives, with the exception of Objectives 3 and 4, as this alternative would not maximize the allowable development footprint on-site and would not provide as many job opportunities as the project.
1.5.3 Environmentally Superior Alternative
Table 1 -2 provides a qualitative comparison of the impacts for each alternative compared to the project. As shown in Table 1-2, the No Project/No Development Alternative would eliminate all of the significant impacts identified for the project. However, the No Project/No Development Alternative would not meet any of the project objectives. Additionally, there is no certainty that the project site would remain undeveloped in perpetuity.
CEQA Guidelines Section 15126.6(e)(2) states that if the No Project alternative is identified as the environmentally superior alternative, then an environmentally superior alternative should be identified among the other alternatives.
Among the other alternatives, not including the project, the Reduced Development Intensity Alternative would be considered the environmentally superior alternative because it would potentially provide a reduced level of impact in some environmental analysi s areas including air quality, greenhouse gas, and geology and soils . However, such impacts under this alternative would still remain as less than significant, similar to the project. The Reduced Development Intensity Alternative would also result in decreased footprint specific impacts, such as those related to cultural resources, biological resources, and tribal cultural resources. However, mitigation measures would still be required to mitigate impacts to these environmental resources. Under this alternative, significant and unavoidable transportation impacts under the project would be reduced to less than significant, as this alternative would screen out of VMT due to the 21,800 SF building size falling under the City’s Transportation Impact Analysis Guidelines Small Project criteria (i.e., fewer than 110 daily trips). 1 Executive Summary
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This alternative would meet all of the project objectives, with the exception of Objectives 3 and 4, as this alternative would not maximize the allowable development footprint on-site and would not provide as many job opportunities as the project.
Table 1-2
Comparison of Impacts of Project and Alternatives
Environmental Topic Project
No Project/No
Development
Alternative
Reduced Development
Intensity Alternative
Aesthetics LTS No Impact (Reduced) LTS (Same/Reduced)
Air Quality LTS No Impact (Reduced) LTS (Same/Reduced)
Biological Resources LTSM No Impact (Reduced) LTSM (Same/Reduced) Cultural Resources LTSM No Impact (Reduced) LTSM (Same/Reduced) Geology and Soils LTSM No Impact (Reduced) LTSM (Same/Reduced) Greenhouse Gas Emissions LTS No Impact (Reduced) LTS (Same/Reduced) Hazards and Hazardous Materials LTS No Impact (Reduced) LTS (Same) Hydrology and Water Quality LTS No Impact (Reduced) LTS (Same) Land Use LTS No Impact (Reduced) LTS (Same)
Noise LTS No Impact (Reduced) LTS (Same)
Population and Housing LTS No Impact (Reduced) LTS (Same) Public Services LTS No Impact (Reduced) LTS (Same)
Recreation LTS No Impact (Reduced) LTS (Same)
Transportation SU No Impact (Reduced) LTS (Reduced)
Tribal Cultural Resources LTSM No Impact (Reduced) LTSM (Same/Reduced) Utilities and Service Systems LTS No Impact (Reduced) LTS (same) Wildfire LTS No Impact (Reduced) LTS (same)
Notes: Impact Status: LTS = Less Than Significant Impact; LTS M = Less Than Significant with Mitigation; SU = Significant and Unavoidable
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2 PROJECT DESCRIPTION, LOCATION, AND
ENVIRONMENTAL SETTING
As required by Section 15124 of the California Environmental Quality Act (CEQA) Guidelines, this chapter describes the Hughes Circuits Project ( project), and includes a statement of the project objectives, a general description of the project ’s technical, economic, and environmental characteristics, and a summary of the discretionary actions required to approve the project. The project provides guidelines and standards for the implementation of future development of the project site.
2.1 PROJECT OBJECTIVES
Section 15124(b) of the CEQA Guidelines requires that an environmental impact report (EIR) include a statement of the project objectives. The project objectives include the following:
1. Expand the existing Hughes Circuits facilities to a nearby location for ease of continued operation and access.
2. Concentrate non-residential uses near existing roadways, highways, and freeways in an effort to isolate and reduce any potential environmental impacts related to truck traffic congestion, air emissions, and industrial noise to the greatest extent feasible.
3. Develop a fiscally sound and employment-generating land use that maximizes the use of the light-industrial zoned area.
4. Restore, manage, and conserve sensitive on-site biological resources, to the extent feasible, while accommodating and maximizing development on-site consistent with the General Plan land use and zoning designation.
5. Promote infill development and develop a site that is served by existing utilities, services, and street access.
2.2 PROJECT DESCRIPTION
The approximately 10.46-acre project site is located at the northeast corner of South Pacific Street and South Pacific Street within the City of San Marcos (City), California. The vacant project site is composed of Assessor’s Parcel Numbers 219-223-20-00 and 219-223-22-00 and sits north of South Pacific Street on one side and east of South Pacific Street on the other. The project location and project site boundary are shown in Figure 2-1, Project Location, and Figure 2-2, Project Site and Surroundings.
The project consists of development of a 67,410 -square-foot (SF) light industrial building to support the expansion of the existing operations of Hughes Circuits Inc., currently located adjacent to the project site to the south, at 546 S. Pacific Street. The 67,410 SF light industrial building includes a 56,310 SF first floor, and a 11,100 SF mezzanine. The proposed light industrial building would be 2 Project Description
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located at the western -most portion of the project site, and the disturbance area associated with project construction would be limited to approximately 113,877 SF or 2.6 1 acres of the 10.46-acre project site. Proposed development would only occur within Assessor’s Parcel Number 219-223-20-00. The proposed light industrial building would include a fire control room, MPOE room, trash enclosure, outdoor amenity area, electrical room, and grade level loading dock s.
Parking for the proposed building would include 72 parking spaces, including 4 electric vehicle charging stations, 9 carpool and zero emission parking stalls, 4 accessible stalls, and 1 U.S. Postal Service parking stall. Additionally, 4 short-term bicycle parking spaces and 4 long-term bicycle parking spaces would be provided. Furthermore, the project would incorporate approximately 9,700 SF of rooftop mounted solar photovoltaic panels.
Access to the proposed building would be provided via two new driveways along S. Pacific Street, one at the northwestern boundary of the proposed building site, and the other at the southeastern boundary of the proposed building site, as shown in Figure 2 -3, Site Plan. Stormwater basins and associated landscaping would be incorporated along the perimeter of the proposed light industrial building. Approximately 60 employees would work out of the proposed light industrial building.
The project site is currently designated as Light Industrial (LI) under the City’s General Plan Land Use Map (City of San Marcos 2022) , and has a zoning designation of Light Industrial (L-I) (City of San Marcos 2023). The project pro poses a Light Industrial land use, consistent with the City ’s land use designation for the project site.
Topography within the review area is relatively flat with multiple wetlands, including vernal pools, and vegetation communities throughout; additionally, a parcel owned by the San Diego County Water Authority right-of-way as well as a n unpaved walking path bisect the site. Elevation ranges from approximately 520 feet above mean sea level in the eastern portion of the project site to 535 feet above mean sea level in the northwest portion of the project site. Adjacent land uses include mixed commercial development to the north and south, a public recreational park (Bradley Park) to the west, and undeveloped land to the east.
2.2.1 Discretionary Actions Required of the City
The requested project entitlements/discretionary actions by the City include the following:
• Site Development Plan – The Site Development Plan approves specific development configurations for the site.
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2.2.2 Project Characteristics
Land Uses
As described above, the project consists of development of a 67,410 SF light industrial building on a currently vacant site, to support the expansion of the existing operations of Hughes Circuits Inc., located adjacent to the project site to the south, at 546 S. Pacific Street. The proposed 67,410 SF light industrial building would be located at the western -most portion of the project site, and the disturbance area associated with project construction would be limited to approximately 113,877 SF or 2.61 acres of the 10.46-acre project site. The remaining approximately 7.85 acres within the project boundary would remain in its current condition. The proposed building would have a maximum height of 43 feet.
Circulation and Access
The project site is on a vacant parcel, adjacent to S. Pacific Street to the west and south. Pacific Street is identified as an unclassified Major Road in the City of San Marcos Mobility Element. Pacific Street is built as a two -lane undivided roadway for its entire length from San Marcos Boulevard to north of Grand Avenue. Sidewalks are generally not provided on Pacific Street and there are no bicycle facilities.
The project would be accessible from two points on S. Pacific Street, as shown in Figure 2 -3. The California Fire Code, along with the San Marcos Fire Department, administers the rules and regulations on fire access design. The project would be designed to provide fire and emergency responders with suitable fire access roads, dimensions, and surfaces (Chapter 5, Section 503.1 through Section 503.4 of the California Fire Code), an adequate number of emergency rated entrances to the community (Appendix D, Section D106 of the California Fire Code), and entryway gate access for first responders (Chapter 5 of the California Fire Code, Section 503.6). Please refer to Section 3.15, Transportation, of this EIR for a detailed description and analysis of proposed access and circulation.
Parking
On-site parking for the proposed building would include 72 parking spaces, including 4 electric vehicle charging stations, 9 carpool and zero emission parking stalls, 4 accessible stalls, and 1 U.S. Postal Service parking stall. Additionally, 4 short -term bicycle parking spaces in the form of outdoor bicycle racks and 4 long-term bicycle parking spaces in the form of indoor bicycle lockers would be provided.
The project would comply with the City’s required parking ratios for Light Industrial development. 2 Project Description
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Public Utilities
Water Facilities
There are existing 855 Zone and 920 Zone water facilities in the vicinity of the project site. The 920 Zone facilities consist of 24-inch and 30-inch transmission lines that do not provide direct service to properties in the area. Water service to existing development in the area is from connections to the 855 Zone which includes two 12 -inch lines within Pacific Street, along the southern and western boundaries of the project site.
The property is within the Vallecitos Water District service area for water service. Water service for potable residential use and fire service to the project site would be provided by the Vallecitos Water District. The project would connect to existing water lines in South Pacific Street. The proposed development is expected to result in an increase of approximately 3,393 gallons per day in water demand. Please refer to Section 3.17, Utilities and Service Systems, of this EIR for a detailed description and analysis of proposed utility connections.
Sewer Facilities
There are existing gravity sewer lines within South Pacific Street and one line that runs through the project site. The sewer line in South Pacific Street’s depth is 8 to 12 feet, increasing in depth as it goes north. The existing sewer main that runs through the project site would be relocated to South Pacific Street. Sewer service to the project site would consist of constructing private on-site sewer lines and connecting to the public system at point locations. The connections to the existing system are outlined in Section 3.17 of this EIR.
Site Drainage
Water arrives on site via natural rainfall and off-site runoff. The majority of the existing off-site surface slopes generally from the north to the south. When the water reaches South Pacific Street along the west border of the project site, it flows into the existing dual 48-inch pipes then flow through vacant property before entering the project area. When water reaches the north edge of the project site, it flows along the slope until it reaches the point of connection at the southern edge of the proper ty at South Pacific Street.
Per Municipal Separate Storm Sewer System requirements, stormwater flows on -site would be conveyed to biofiltration systems located on the eastern boundary of the development area through storm drains throughout the project site , where water would be treated prior to being discharged.
Improvements also include a new curb and gutter system and a dispersion area between South Pacific Street and the open space area, east of the development area. Storm drainage components would properly handle runoff to meet re gulatory requirements and to ensure that post -development run-off quantifies rates that are similar to or less than pre -development conditions. The project would 2 Project Description
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incorporate appropriate design of on- and off-site drainage facilities and would prepare and implement a S tormwater Pollution Prevention Plan , S torm Water Quality Management Plan, and best management practices. Please refer to Section 3.17 of this EIR which describes and analyzes project utilities and service systems in detail.
Electrical and Gas
Electricity and natural gas would be provided by San Diego Gas & Electric. Electrical facilities throughout the City include a combination of above -ground and below -ground electrical distribution lines and utilities structures. The City fiber -optic network is facilitated by a 72 -strand fiber-optic line that runs on various streets throughout the City. All major arterials in the City have implemented fiber optics. The project would require constructing private utility lines to connect to existing electrical lines and natural gas pipeline within South Pacific Street.
2.3 ENVIRONMENTAL SETTING
2.3.1 Existing Land Uses and Setting
The project site is currently vacant and has no existing impervious areas. Topography within the project boundary is relatively flat with multiple wetlands , vernal pools, and vegetation communities throughout; additionally, a parcel owned by the San Diego County Water Authority right-of-way as well as a dirt walking path bisect the site. Elevation ranges from approximately 520 feet above mean sea level in the eastern portion of the review area to 535 feet above mean sea level in the northwest portion of the review area. Adjacent land uses in clude mixed commercial development to the north and south, a public recreational park (Bradley Park) to the west, and undeveloped land to the east.
The closest freeway is State Route 78 located approximately 0.8 miles north of the project site.
2.3.2 Existing Land Use and Zoning Designations
Existing General Plan Land Use Designation
As described above, the existing General Plan land use designation for the project site is Light Industrial (LI) (City of San Marcos 2022). Development allowed under this land use designation must be consistent with those uses outlined in the City ’s municipal code and zoning ordinance, as well as the Light Industrial land use designation of the General Plan. Please refer to Figure 2 -4, Existing General Plan Land Use.
Existing Zoning Designation
Existing zoning of the project site is Light Industrial (L-I). The purpose of the Light -Industrial zoning designation is to “provide for the grouping of light- and medium-intensity industrial and support service uses in a business -supportive setting. Generally, these areas will not include pedestrian -oriented 2 Project Description
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businesses and will serve the loading, delivery, and indoor warehousing needs of light industrial space” (City of San Marcos Municipal Code Section 20.230.020). The L-I Zone is intended to implement and be consistent with the Light Industrial land use designation of the General Plan ( City of San Marcos Municipal Code Section 20.230.020). Please refer to Figure 2-5, Existing Zoning.
2.3.3 Regional Setting
The following provides a general description of various aspects of the project’s environmental setting.
Additional descriptions of the project’s environmental setting as it related to environmental issue areas can be found in Chapter 3, Environmental Analysis, and Chapter 5, Effects Found Not To Be Significant, of this EIR.
Climate
The weather of the San Diego region, as in most of Southern California, is influenced by the Pacific Ocean and its semi -permanent high-pressure systems that result in dry, warm summers and mild, occasionally wet winters (City of San Diego 2007). The average summertime daily high temperature in the region is above 77°F. The average wintertime low temperature is approximately 46°F. Average precipitation in the local area is approximately 10 inches per year, with the bulk of precipitation falling between late November and early April (WeatherSpark 2023).
Air Basin
The City and project site is within the San Diego Air Basin (SDAB) and is under the jurisdiction of the San Diego Air Pollution Control District. The SDAB is one of 15 air basins that geographically divide the State of California. The SDAB lies in the southwest corner of California and comprises the entire San Diego region, covering 4,260 square miles, and it is an area of high air pollution potential. The SDAB experiences warm summers, mild winters, infrequent rainfalls, light winds, and moderate humidity. This usually mild climatological pattern is interrupted infrequently by periods of extremely hot weather, winter storms, or Santa Ana winds.
The SDAB is currently classified as a federal nonattainment area for ozone (O 3) and a state nonattainment area for particulate matter less than or equal to 10 microns (coarse particulate matter [PM10]), particulate matter less than or equal to 2.5 microns (fine particulate matter [PM2.5]), and O3 (EPA 2021 [national]; CARB 2020 [state]).
Soils
Two soil series are mapped in the project boundary: Las Flores loamy fine sand, 2% to 9% slopes (LeC) and Placentia sandy loam, thick surface, 0% to 2% slopes (PfA), which are both moderately well drained and listed as hydric soils (USDA 2021). Las Flores soils are on hillslopes and formed in residuum 2 Project Description
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weathered from siliceous calcareous sandstone, while Placentia soils are on alluvial fans and formed in alluvium derived from granite.
Terrain and Topography
The project site is characterized by undeveloped terrain and has no existing impervious areas. As previously described, topography within the project boundary is relatively flat with multiple wetlands and vegetation communities throughout; additionally, a parcel owned by the San Diego County Water Authority right-of-way as well as an unpaved walking path bisect the site.
Watersheds and Hydrology
The project site occurs within the central portion of the San Marcos Creek Watershed (Hydrologic Unit Code 180703030503), within the greater boundaries of the San Marcos Creek -Frontal Gulf of Santa Catalina Parent Watershed ( Hydrologic Unit Code 1807030305). The San Marcos Creek Watershed is approximately 53 square miles (34,246 acres) and consists of two major tributaries:
San Marcos Creek and Encinitas Creek. These tributaries converge prior to discharging into the Pacific Ocean at Batiquitos Lagoon. This subwatershed consists of two tributaries: Las Posas Branch and Twin Oaks Branch of San Marcos Creek. These tributaries converge prior to discharging into Lake San Marcos south of the project site. The Las Posas Branch tributary to San Marcos Creek runs directly on the border of the western side of the property. A second tributary runs through the site on the eastern side to San Marcos Creek. This tributary is mapped within a floodplain and characterized as a regulatory floodway. In addition, there are five distinct mapped vernal pool watersheds consisting of San Diego Mesa Claypan vernal pools located on the central and eastern portions of the project site.
Habitat
Within the project boundary, 16 vegetation communities and/or land covers were identified and categorized into three community subgroups: sensitive uplands, sensitive wetlands/riparian habitat, and non-sensitive uplands. Sensitive uplands within the review area consist of Diegan coastal sage scrub, Diegan coastal sage scrub -Baccharis dominated, non -native grassland -artichoke-thistle dominated, non-native grassland-broadleaf dominated, valley needle grassland, and wildflower fields.
Sensitive wetlands/riparian habitats within the review area include arundo-dominated riparian habitat, disturbed wetlands, emergent wetlands, San Diego Mesa claypan vernal pools, southern willow scrub, and Tamarisk scrub. Non-sensitive uplands consist of disturbed habitat and eucalyptus woodland.
Multiple hydrophytic vegetation communities and special-status plant species are present surrounding the San Diego mesa Claypan vernal pools, wildflower fields, and emergent wetlands identified within the project boundary. San Diego button celery ( Eryngium aristulatum ) thread -leaved brodiaea (Brodiaea filifolia ) are federal - and state -listed endangered species with a California Native Plant Society’s Rare Plant Rank of 1B.1. Plants with a California Rare Plant Rank of 1B.1 are rare throughout 2 Project Description
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their range with the majority of them endemic to and seriously threatened in California (CNPS 2021).
Orcutt’s brodiaea (Brodiaea orcuttia) occurs within and surrounding the wildflower fields on the central and eastern portions of the review area. This species is also categorized under California Native Plant Society’s Rare Plant Rank of 1B.1 and is intermixed with thread -leaved brodiaea within the central portion of the project site. Please refer to Section 3.3, Biological Resources, of this EIR for a detailed analysis of biological resources.
2.3.4 Public Services
The following provides a general description of public services within the City that would serve the project. Considering the proposed development and project purpose, schools, parks and other public services are not described, as no habitable structures are proposed. Additional detail on public services can be found in Section 3.13, Public Services, of this EIR.
Fire Protection
The project site is within the San Marcos Fire Protection District boundary. The City of San Marcos Fire Department would provide fire protection and emergency medical services to development at the project. The San Marcos Fire Department provides structural fire protection and advanced life support- level emergency medical services within the City limits; unincorporated territory adjacent to the City’s northern boundary; discontinuous, unincorporated areas between the City of San Marcos and the City of Escondido; and the community of Lake San Marcos. The San Marcos Fire Department operates two Fire Stations (Stations 1 and 32) that would respond to an incident at the project site.
Police Protection
Police protection services for the project would be provided by the San Diego County Sheriff ’s Department under contract with the City. The project site would be served by the Sheriff’s San Marcos Station, located at 182 Santar Place in the northeast quadrant of the City.
2.4 INTENDED USES FOR EIR
This EIR was prepared in accordance with CEQA (California Public Resources Code Section 21000 et seq.), CEQA Guidelines (14 CCR 15000 et seq.), and the City’s Environmental Review Procedures.
The EIR is an informational document that will provide the City ’s decision makers, public agencies, responsible and trustee agencies, and members of the public with information about (1) the potential for significant adverse environmental impacts that would result from the development of the project, (2) possible ways to minimize any significant environmental impacts, and (3) feasible alternatives to the project that would reduce or avoid significant impacts associated with the project (California Public Resources Code Section 21002.1[a]; 14 CCR 15121[a]). Responsible and trustee agencies may use 2 Project Description
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this EIR to fulfill their legal authority to issue permits for the project. The analysis and findings in this EIR reflect the independent judgment of the City.
Lead Agency
As defined by CEQA Guidelines Section 15367, a “Lead Agency” means the public agency which has the principal responsibility for carrying out or approving a project. The City is the lead agency for the project because it will perform the entitlement processing of the project. As the designated lead agency, the City has assumed responsibility for preparing this EIR, and the analysis and findings in this EIR reflect the City ’s independent judgment. When deciding whether to approve the project, the City will us e the information in this EIR to consider potential impacts to the physical environment associated with the project.
Responsible Agencies
As defined by CEQA Guidelines Section 15381, a “Responsible Agency” includes all public agencies other than the lead agency which have discretionary approval power over the project, such as the Vallecitos Water District. Subsequent to certification of the Final EIR, agencies with permitting authority over all or portions of the project will use the Final EIR as the basis for their evaluation of environmental effects related to the project that will culminate with the approval or denial of applicable permits.
Trustee Agencies
As defined by CEQA Guidelines Section 15386, a “Trustee Agency” is a public agency having jurisdiction by law over natural resources affected by a project which are held in trust for the people of the State of California. For example, trustee agencies include the California Department of Fish and Wildlife with regard to the fish and wildlife of the state, to designated rare or endangered native plants, and to game refuges, ecological reserves, and other areas administered by the California Department of Fish and Wildlife.
2.4.1 Scope of the EIR
For the project, the City determined that a project EIR, as defined by CEQA Guidelines Section 15161, was required. The City made this determination based on the development proposed for the project site and the discretionary actions requested. This EIR evaluates all subject areas listed in Appendix G to the CEQA Guidelines with the exception of those subject areas determined to have no impact on the environment, which are addressed in Chapter 5 of this EIR . Chapter 3 of this EIR evaluates the following subject areas in detail: aesthetics, air quality, biological resources, cultural resources, energy conservation, geology and soils, greenhouse gas emissions, hazards and hazardous materials, hydrology and water quality, land use and planning, noise, public services, transportation, tribal cultural resources, utilities and service systems, cumulative impacts, and growth -inducing impacts.
Chapter 4, Alternatives, analyzes alternatives to the project. 2 Project Description
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As a “project EIR,” this EIR is “focused primarily on the changes in the environment that would result from the project” (CEQA Guidelines Section 15161). In addition, as a project EIR, this EIR examines all phases of the project including planning, construction, and operation ( CEQA Guidelines Section 15161). Where environmental impacts have been determined to be significant, this EIR recommends mitigation measures directed at reducing or avoiding those significant environmental impacts. Alternatives to the project are identified to evaluate whether there are ways to minimize or avoid significant impacts associated with the project.
2.4.2 Notice of Preparation and Scoping
CEQA establishes mechanisms to inform the public and decision makers about the nature of the project and the extent and types of impacts that the project and alternatives to the project would have on the environment should the project or alternatives be implemented. Pursuant to Section 15082 of the CEQA Guidelines, the City circulated a Notice of Preparation (NOP) dated February 22, 2023, to interested agencies, organizations, and parties. The NOP was also sent to the State Clearinghouse at the California Office of Planning and Research. The State Clearinghouse assigned a state identification number (SCH No. 2023020497) to this EIR.
The NOP is intended to encourage interagency and public communication regarding the project so that agencies, organizations, and individuals are afforded an opportunity to respond with specific comments and/or questions regarding the scope and content of the EIR. A public scoping meeting was held on March 9, 2023, at San Marcos City Hall in the Valley of Discovery Room (1 Civic Center Drive) to gather additional public input. The 30 -day public scoping period ended on March 24, 2023 .
Comments received during the NOP public scoping period were considered part of the preparation of this EIR. The NOP and written comments are included in Appendix A to this EIR. Comments covered numerous topics, including biological resources, cultural resources, hazards, and traffic. Public scoping comments regarding the project ’s potential impact on the environment have been incorporated in the analysis in Chapters 3, 4, 5, and 6 of this EIR.
2.4.3 Draft EIR and Public Review
This Draft EIR was prepared under the direction and supervision of the City. The Draft EIR will be made available to members of the public, responsible agencies, and interested parties for a 45 -day public review period in accordance with CEQA Guidelines Section 15105.
Public review of the Draft EIR is intended to focus “on the sufficiency of the document in identifying and analyzing the possible impacts on the environment and ways in which the significant effects of the project might be avoided or mitigated” (14 CCR 15204). The Notice of Completion of the Draft EIR will be filed with the State Clearinghouse as required by CEQA Guidelines Section 15085. In addition, the Notice of Availability of the Draft EIR will be distributed pursuant to CEQA Guidelines Section 15087. Interested parties may provide comments on the Draft EIR in written form. This EIR 2 Project Description
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and related technical appendices are available for review during the 45 -day public review period at the following locations:
City of San Marcos Planning Division
1 Civic Center Drive
San Marcos, California 92069
San Diego County Library San Marcos Branch
2 Civic Center Drive
San Marcos, California 92069
City of San Marcos website: https://www.san-marcos.net/ Interested agencies and members of the public may submit written comments on the adequacy of the Draft EIR to the City ’s Development Services Department at the address above, addressed to Chris Garcia, Associate Planner, or emailed at [email protected]. Comments on the Draft EIR must be received by the close of business on the last day of the 45 -day review period. Electronic filing and posting of the EIR would be in compliance with Assembly Bill 819, as applicable.
2.4.4 Final EIR Publication and Certification
Once the 45-day public review period has concluded, the City will review all public comments on the Draft EIR and provide a written response to all written comments pertaining to environmental issues as part of the Final EIR. The Final EIR will include all written comments received during the public review period; responses to comments; and, if applicable, edits and errata made to the Draft EIR. The City will then consider certification of the Final EIR (14 CCR 15090). If the EIR is certified, the City may consider project approval (14 CCR 15092).
The Draft EIR was circulated for public review from December 21, 2023, through February 5, 2024, in accordance with Section 15105(a) of the CEQA Guidelines. A total of six written comment letters were received on the Draft EIR from agencies and organizations, as shown in Table 2 -1. Public comment letters and responses to each comment letter received are included as Appendix K to the Final EIR. Each of the written comment letters have been assigned an alphanumeric label, and the individual comments within each written comment letter are bracketed and numbered. For example, Comment Letter A1 contains six comments that are numbered A1-1 through A1-6.
The responses to each comment on the Draft EIR represent a good -faith, reasoned effort to address the environmental issues identified by the comment. Under the CEQA Guidelines, the City, as lead agency, is not required to respond to all comments on the Dra ft EIR, but only those comments that raise environmental issues. In accordance with CEQA Guidelines Sections 15088 and 15204, the City has independently evaluated the comments and prepared written responses describing the disposition of any significant env ironmental issues raised (see Appendix K to the Final EIR). CEQA does not require the City to conduct every test or perform all research, study, and experimentation recommended or demanded by commenters.
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Table 2-1.
Comment Letters and Commenters
Comment Letter Commenter Date Received
Agency
A1 California Department of Transportation January 22, 2024 A2 County of San Diego Public Works February 5, 2024
A3 San Diego County Water Authority February 5, 2024
A4 U.S. Fish and Wildlife Service February 12, 2024
Organizations
O1 San Diego County Archaeological Society January 13, 2024 O2 Supporters Alliance for Environmental Responsibility February 5, 2024
Changes have been made to the Final EIR in strikeout/underline format in response to comments and to provide updates and clarifications to information provided in the Draft EIR. Consistent with CEQA Guidelines Section 15088.5(b), these revisions have been made to clarify text for consistency or revise punctuation as appropriate throughout the document, and these revisions do not result in new significant information that would require recirculation of the document.
Revisions made throughout the Final EIR are in response to input from agencies and stakeholders as provided in the comments to the Draft EIR. Table 2 -2 summarizes changes made to the EIR, by EIR chapter and section, and shows original text included and proposed changes to the text.
Table 2-2.
Summary of Changes to the Draft EIR
Section Original Text Proposed Change(s)
Introduction (new chapter)
Executive Summary
Table 1-1, Page
1-2 (Impact BIO-
1)
Implementation of MM-BIO-3 through
MM-BIO-11
Implementation of MM-BIO-3 through MM-
BIO-13
Table 1-1, Page
1-2 (Impact TRA-
1)
Implementation of MM-TRA-1 and MM-
TRA-2
Implementation of MM-TRA-1 through MM-
TRA-3
Project Description
Section 2.2,
Section 2.3.1,
Section 2.3.3,
Topography within the review area is
relatively flat with multiple wetlands,
including vernal pools, and vegetation
communities throughout; additionally, a
San Diego County Water Authority right-
of-way as well as an unpaved walking
path bisect the site.
Topography within the review area is
relatively flat with multiple wetlands,
including vernal pools, and vegetation
communities throughout; additionally, a
parcel owned by the San Diego County Water
Authority right-of-way as well as an unpaved
walking path bisect the site.
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Table 2-2.
Summary of Changes to the Draft EIR
Section Original Text Proposed Change(s)
Section 2.3.4,
Fire Protection
The project site is within the San Marcos
Fire Protection District boundary. The
City of San Marcos Fire Department
would provide fire protection and
emergency medical services to
development at the project. The San
Marcos Fire Department provides
structural fire protection and advanced
life support-level emergency medical
services within the City limits;
unincorporated territory adjacent to the
City’s northern boundary; discontinuous,
unincorporated areas between the City
of San Marcos and the City of
Escondido; and the community of Lake
San Marcos. The San Marcos Fire
Department operates two Fire Stations
(Stations 1 and 3) that would respond to
an incident at the project site.
Fire Protection
The project site is within the San Marcos Fire
Protection District boundary. The City of San
Marcos Fire Department would provide fire
protection and emergency medical services
to development at the project. The San
Marcos Fire Department provides structural
fire protection and advanced life support-
level emergency medical services within the
City limits; unincorporated territory adjacent
to the City’s northern boundary;
discontinuous, unincorporated areas
between the City of San Marcos and the City
of Escondido; and the community of Lake
San Marcos. The San Marcos Fire
Department operates two Fire Stations
(Stations 1 and 32) that would respond to an
incident at the project site.
Section 2.4.4,
—- The Draft EIR was circulated for public review
from December 21, 2023, through February
5, 2024, in accordance with Section
15105(a) of the CEQA Guidelines. A total of
six written comment letters were received on
the Draft EIR from agencies and
organizations, as shown in Table 2-1. Public
comment letters and responses to each
comment letter received are included as
Appendix K to the Final EIR. Each of the
written comment letters have been assigned
an alphanumeric label, and the individual
comments within each written comment
letter are bracketed and numbered. For
example, Comment Letter A1 contains six
comment that are numbered A1-1 through
A1-6.
The responses to each comment on the Draft
EIR represent a good-faith, reasoned effort to
address the environmental issues identified
by the comment. Under the CEQA Guidelines,
the City, as lead agency, is not required to
respond to all comments on the Draft EIR,
but only those comments that raise
environmental issues. In accordance with
CEQA Guidelines Sections 15088 and
15204, the City has independently evaluated
the comments and prepared written
responses describing the disposition of any
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Table 2-2.
Summary of Changes to the Draft EIR
Section Original Text Proposed Change(s)
significant environmental issues raised (see
Appendix K to the Final EIR). CEQA does not
require the City to conduct every test or
perform all research, study, and
experimentation recommended or demanded
by commenters.
(Table 2-1)
Changes have been made to the Final EIR in
strikeout/underline format in response to
comments and to provide updates and
clarifications to information provided in the
Draft EIR. Consistent with CEQA Guidelines
Section 15088.5(b), these revisions have
been made to clarify text for consistency or
revise punctuation as appropriate throughout
the document, and these revisions do not
result in new significant information that
would require recirculation of the document.
Revisions made throughout the Final EIR are
in response to input from agencies and
stakeholders as provided in the comments to
the Draft EIR. Table 2-2 summarizes changes
made to the EIR, by EIR chapter and section,
and shows original text included and
proposed changes to the text.
(Table 2-2)
Section 2.6,
Table 2-1 Table 2-3
Aesthetics
Section 3.1.1.1,
The topography within the project site is
relatively flat with multiple wetlands and
vegetation communities throughout;
additionally, a San Diego County Water
Authority right-of-way as well as a dirt
walking path bisect the site.
The topography within the project site is
relatively flat with multiple wetlands and
vegetation communities throughout;
additionally, a parcel owned by the San Diego
County Water Authority right-of-way as well as
a dirt walking path bisect the site.
Biological Resources
Section 3.3.1,
The on-site land use is currently
unoccupied and undeveloped apart from
an approximately 108-foot-wide San
Diego County Water Authority dirt right-
of-way lane bisecting the property.
The on-site land use is currently unoccupied
and undeveloped apart from two 100-foot-
wide parcels an approximately 108-foot-wide
San Diego County Water Authority dirt right-
of-way lane owned by the San Diego Water
Authority bisecting project the project
property.
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Table 2-2.
Summary of Changes to the Draft EIR
Section Original Text Proposed Change(s)
Section 3.3.7,
Pages 3.3-37
and 3.3-38
(MM-BIO-1)
On-Site Preservation. Impacts to
sensitive vegetation shall be mitigated
through the on-site preservation of 8.07
acres of sensitive upland and wetland
vegetation. The project shall result in the
preservation of 7.32 acres of sensitive
upland vegetation communities and
0.76 acres of wetland vegetation
communities (which includes 0.02 acres
of restored areas per MM-BIO-2). A land
manager shall be identified to ensure
that the project is managed and
protected in perpetuity. A conservation
easement shall be recorded prior to the
issuance of a grading permit.
On-Site Preservation. Impacts to sensitive
vegetation shall be mitigated through the on-
site preservation of 8.07 acres of sensitive
upland and wetland vegetation. The project
shall result in the preservation of 7.32 acres
of sensitive upland vegetation communities
and 0.76 acres of wetland vegetation
communities (which includes 0.02 acres of
restored areas per MM-BIO-2). A land
manager shall be identified to ensure that
the project is managed and protected in
perpetuity. A conservation easement for the
8.07 acres shall be recorded prior to the
issuance of a grading permit or other timing
agreed upon by the Planning Division Director
or their designee.
Section 3.3.7,
(MM-BIO-2)
Vernal Pool Restoration. Vernal pool
restoration will include some minor
recontouring of the existing vernal pool
basin where appropriate, mostly where
vernal pools have been altered by road
ruts, trail berms, and other past
disturbances to the site. Along with
this minor recontouring, weed control
will also be conducted in the vernal
pools and surrounding watershed
areas. Weed control will consist of a
combination of herbicide application,
mowing (line trimmers), and hand
weeding. Vernal pools on site that are
low in diversity, particularly those at
the south end of the project, will be
planted and seeded with vernal pools
species known from the site. Seed
collected for this purpose will come
from on-site sources only. This will
include, but is not limited to San Diego
button celery, spreading navarretia,
pale spikerush, annual coast plantago
(Plantago elongata), aquatic pygmy
plant (Crassula aquatica), toad rush
(Juncus bufonius), smooth boisduvalia
(Epilobium campestris), and wooly
marbles (Psilocarphus brevissimus).
Vernal Pool Restoration. Vernal pool
restoration will include some minor
recontouring of the existing vernal pool basin
where appropriate, mostly where vernal pools
have been altered by road ruts, trail berms,
and other past disturbances to the site. Any
recontouring will avoid impacts to existing
vernal pools and existing sensitive species
and is intended to develop new pools or to
expand pools from existing locations. Along
with this minor recontouring, weed control
will also be conducted in the vernal pools and
surrounding watershed areas. Weed control
will consist of a combination of herbicide
application, mowing (line trimmers), and
hand weeding. Vernal pools on site that are
low in diversity, particularly those at the
south end of the project, will be planted and
seeded with vernal pools species known from
the site. Seed collected for this purpose will
come from on-site sources only. This will
include, but is not limited to San Diego
button celery, spreading navarretia, pale
spikerush, annual coast plantago (Plantago
elongata), aquatic pygmy plant (Crassula
aquatica), toad rush (Juncus bufonius),
smooth boisduvalia (Epilobium campestris),
and wooly marbles (Psilocarphus
brevissimus). Mitigation will not occur within
the San Diego County Water Authority owned
parcel. The project applicant will consult with
the U.S. Fish and Wildlife Service to ensure
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Table 2-2.
Summary of Changes to the Draft EIR
Section Original Text Proposed Change(s)
that the mitigation plan does not impact
listed species.
Section 3.3.7,
(MM-BIO-2)
Habitat Restoration Plan. The applicant
shall prepare a conceptual habitat
restoration plan outlining the restoration
described above. Upon approval a 5-year
implementation effort would follow the
plan, including topographic
reconstruction, weed control, seeding,
container planting, irrigation, and a
program of monitoring and reporting.
The restoration plan shall be prepared
by persons with expertise in southern
California ecosystems and native plant
revegetation techniques. The plan
should include, at a minimum: (a) a
description of the mitigation site; (b) the
plant species to be used, container
sizes, and seeding rates; (c) a schematic
depicting the mitigation area; (d)
planting schedule; (e) a description of
the irrigation methodology; (f) measures
to control non-native vegetation on site;
(g) specific success criteria; (h) a
detailed monitoring program; (i)
contingency measures should the
success criteria not be met; and (j)
identification of the party responsible for
meeting the success criteria and
providing for conservation of the
mitigation site in perpetuity.
Habitat Restoration Plan. The applicant shall
prepare a conceptual habitat restoration plan
outlining the restoration described above.
Upon approval a 5-year implementation effort
would follow the plan, including topographic
reconstruction, weed control, seeding,
container planting, irrigation, and a program
of monitoring and reporting.
The restoration plan shall be prepared by
persons with expertise in southern California
ecosystems and native plant revegetation
techniques. The plan should include, at a
minimum: (a) a description of the mitigation
site; (b) the plant species to be used,
container sizes, and seeding rates; (c) a
schematic depicting the mitigation area; (d)
planting schedule; (e) a description of the
irrigation methodology; (f) measures to
control non-native vegetation on site; (g)
specific success criteria; (h) a detailed
monitoring program; (i) contingency
measures should the success criteria not be
met; and (j) identification of the party
responsible for meeting the success criteria
and providing for conservation of the
mitigation site in perpetuity. As part of the
mitigation planning a PAR-like cost evaluation
will be developed and approved by USFWS to
help determine long term costs in the
endowment required to support those costs.
The applicant is required to fund the
endowment before the issuance of grading
permits, and the endowment agreement shall
be approved by USFWS.
Section 3.3.7,
(MM-BIO-13)
Federal and State Agency Permits. Prior
to impacts occurring to U.S. Army Corps
of Engineers (USACE), Regional Water
Quality Control Board (RWQCB), and
California Department of Fish and
Wildlife (CDFW) (collectively, the
Resource Agencies) jurisdictional
aquatic resources, the project applicant
or its designee shall obtain the following
permits: USACE 404 permit, RWQCB
401 Water Quality Certification, and
Federal and State Agency Permits. Prior to
impacts occurring to U.S. Army Corps of
Engineers (USACE), Regional Water Quality
Control Board (RWQCB), and California
Department of Fish and Wildlife (CDFW)
(collectively, the Resource Agencies)
jurisdictional aquatic resources, the project
applicant or its designee shall obtain the
following permits: USACE 404 permit, RWQCB
401 Water Quality Certification, and CDFW
Fish and Game Code 1600 Streambed
Alteration Agreement. The project applicant
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Table 2-2.
Summary of Changes to the Draft EIR
Section Original Text Proposed Change(s)
CDFW Fish and Game Code 1600
Streambed Alteration Agreement.
will consult with the U.S. Fish and Wildlife
Service and get approval of the mitigation
plan to ensure that it does not impact listed
species.
Cultural Resources
Section 3.4.1,
Two tribes requested consultation under
AB 52, including the Rincon Band of
Luiseño Indians on May 20, 2022, and
San Luis Rey Band of Mission Indians on
June 6, 2022. The Rincon Band of
Luiseño Indians agreed with the
mitigation measures proposed by Dudek
in the archaeological resources report,
which includes archaeological and tribal
monitoring, and protocols for the
discovery of cultural material and
human remains. Additionally, the Rincon
Band of Luiseño proposed that if export
of soil is planned, consultation with the
affiliated tribes will have to be initiated,
and this was included in the mitigation
measures. The Rincon Band of Luiseño
concluded AB 52 consultation on
December 20, 2022. The San Luis Rey
Band agreed with the proposed
measures for tribal cultural resources for
the project’s environmental document.
The San Luis Rey Band of Mission
Indians concluded AB 52 consultation
on January 12, 2023.
Three Two tribes requested consultation
under AB 52, including the Rincon Band of
Luiseño Indians on May 20, 2022, and the
San Luis Rey Band of Mission Indians on
June 6, 2022, and the San Pasqual Band of
Diegueño Mission Indians on May 11, 2023.
The Rincon Band of Luiseño Indians agreed
with the mitigation measures proposed by
Dudek in the archaeological resources report,
which includes archaeological and tribal
monitoring, and protocols for the discovery of
cultural material and human remains.
Additionally, the Rincon Band of Luiseño
proposed that if export of soil is planned,
consultation with the affiliated tribes will
have to be initiated, and this was included in
the mitigation measures. The Rincon Band of
Luiseño concluded AB 52 consultation on
December 20, 2022. The San Luis Rey Band
agreed with the proposed measures for tribal
cultural resources for the project’s
environmental document. The San Luis Rey
Band of Mission Indians concluded AB 52
consultation on January 12, 2023. The City
provided the San Pasqual Band of Diegueño
Mission Indians with the project Cultural
Reports on May 11, 2023. The San Pasqual
Band of Diegueño Mission Indians requested
inclusion of a Kumeyaay monitor during
construction in a letter to the City on January
10, 2024. The City confirmed a Kumeyaay
monitor would be included in the project’s
conditions of approval, and the San Pasqual
Band of Diegueño Mission Indians concluded
AB 52 consultation on February 14, 2024.
Section 3.4.6,
(MM-CR-2)
Construction Monitoring: Prior to the
issuance of a Grading Permit or ground
disturbing activities, the
Applicant/Owner or Grading Contractor
shall provide written documentation
(either as signed letters, contracts, or
emails) to the City’s Planning Division
stating that a Qualified Archaeologist
and Traditionally and Culturally Affiliated
Construction Monitoring: Prior to the issuance
of a Grading Permit or ground disturbing
activities, the Applicant/Owner or Grading
Contractor shall provide written
documentation (either as signed letters,
contracts, or emails) to the City’s Planning
Division stating that a Qualified Archaeologist
and Traditionally and Culturally Affiliated
Native American monitor (TCA Native
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Table 2-2.
Summary of Changes to the Draft EIR
Section Original Text Proposed Change(s)
Native American monitor (TCA Native
American monitor) have been retained
at the Applicant/Owner or Grading
Contractor’s expense to implement the
construction monitoring program, as
described in the Pre-Excavation
Agreement.
In the event that one or more TCA Tribe
chooses not to enter into an agreement,
or fails to respond to the offer, the City
shall extend the opportunity for another
Tribe to provide a monitor. In the event
that more than one TCA Tribe requests
to provide a TCA Native American
monitor for activities subject to these
measures, the City will allow for either:
1) up to one monitor from each
consulting tribe to be present
simultaneously; or 2) for the tribes to
develop a rotating schedule that
alternates monitoring between the tribes
on a daily or weekly basis. The monitors
shall be provided at least 72 hours’
notice of the initiation of construction
and be kept reasonably apprised of
changes to the construction schedule. In
the event that a monitor is not present
at the scheduled time, work can
continue without the monitor present, as
long as the notice was given and
documented.
American monitor) have been retained at the
Applicant/Owner or Grading Contractor’s
expense to implement the construction
monitoring program, as described in the Pre-
Excavation Agreement. A monitor representing
the San Pasqual Band of Mission Indians shall
be provided the opportunity to monitor, should
they choose to.
Native American monitoring shall include a
monitor representing a TCA Tribe (Luiseño)
and a monitor representing the San Pasqual
Band of Mission Indians (if the San Pasqual
Band elects to monitor). In the event that one
or more TCA Tribe chooses not to enter into an
agreement, or fails to respond to the offer, the
City shall extend the opportunity for another
TCA Tribe to provide a monitor. In the event
that more than one TCA Tribe requests to
provide a TCA Native American monitor for
activities subject to these measures, the City
will allow for either: 1) up to one monitor from
each consulting tribe to be present
simultaneously; or 2) for the tribes to develop
a rotating schedule that alternates monitoring
between the tribes on a daily or weekly basis.
The monitors shall be provided at least 72
hours’ notice of the initiation of construction
and be kept reasonably apprised of changes
to the construction schedule. In the event that
a monitor is not present at the scheduled
time, work can continue without the monitor
present, as long as the notice was given and
documented.
Land Use and Planning
Section 3.10.1,
Topography within the project boundary
is relatively flat with multiple wetlands,
vernal pools, and vegetation
communities throughout; additionally, a
San Diego County Water Authority right-
of-way as well as a dirt walking path
bisect the site.
Topography within the project boundary is
relatively flat with multiple wetlands, vernal
pools, and vegetation communities
throughout; additionally, a parcel of land
owned by the San Diego County Water
Authority right-of-way as well as a dirt walking
path bisect the site.
Tribal Cultural Resources
Section 3.16.1,
The project area is relatively flat; a San
Diego County Water Authority right-of-
way and a dirt walking path bisect the
site.
The project area is relatively flat;, and a
parcel of land owned by the San Diego
County Water Authority right-of-way and a dirt
walking path bisect the site.
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Table 2-2.
Summary of Changes to the Draft EIR
Section Original Text Proposed Change(s)
Section 3.16.1,
Pages 3.16-9
and 3.16-10
Assembly Bill 52 Consultation
In compliance with Assembly Bill (AB)
52, the City, as lead agency, is
responsible for conducting government
to government consultation with
pertinent tribal entities. The City mailed
AB 52 notifications on May 3, 2022, to
California Native American Tribal
representatives (that have requested
notification) who are traditionally or
culturally affiliated with the geographic
area of the project. Three tribes
requested consultation under AB 52,
including the Rincon Band of Luiseño
Indians on May 20, 2022, San Luis Rey
Band of Mission Indians on June 6,
2022, and San Pasqual Band of Mission
Indians. The Rincon Band of Luiseño
Indians agreed with the mitigation
measures proposed by Dudek in the
archaeological resources report, which
includes archaeological and tribal
monitoring, and protocols for the
discovery of cultural material and
human remains. Additionally, the Rincon
Band of Luiseño proposed that if export
of soil is planned, consultation with the
affiliated tribes will have to be initiated,
and this was included in the mitigation
measures. The Rincon Band of Luiseño
concluded AB 52 consultation on
December 20, 2022. The San Luis Rey
Band agreed with the proposed
measures for tribal cultural resources
(MM-CUL-1 through MM-CUL-4) for the
project’s environmental document. The
San Luis Rey Band of Mission Indians
concluded AB 52 consultation on
January 12, 2023. The San Pasqual
Band of Mission Indians requested
consultation on May 11, 2023. As of
November 2, 2023, the City has not
received a letter concluding
consultation.
Assembly Bill 52 Consultation
In compliance with Assembly Bill (AB) 52, the
City, as lead agency, is responsible for
conducting government to government
consultation with pertinent tribal entities. The
City mailed AB 52 notifications on May 3,
2022, to California Native American Tribal
representatives (that have requested
notification) who are traditionally or culturally
affiliated with the geographic area of the
project. Three tribes requested consultation
under AB 52, including the Rincon Band of
Luiseño Indians on May 20, 2022, San Luis
Rey Band of Mission Indians on June 6,
2022, and San Pasqual Band of Mission
Indians on May 11, 2023. The Rincon Band
of Luiseño Indians agreed with the mitigation
measures proposed by Dudek in the
archaeological resources report, which
includes archaeological and tribal monitoring,
and protocols for the discovery of cultural
material and human remains. Additionally,
the Rincon Band of Luiseño proposed that if
export of soil is planned, consultation with
the affiliated tribes will have to be initiated,
and this was included in the mitigation
measures. The Rincon Band of Luiseño
concluded AB 52 consultation on December
20, 2022. The San Luis Rey Band agreed
with the proposed measures for tribal cultural
resources (MM-CUL-1 through MM-CUL-4) for
the project’s environmental document. The
San Luis Rey Band of Mission Indians
concluded AB 52 consultation on January 12,
2023. The San Pasqual Band of Mission
Indians requested consultation on May 11,
2023. The City provided the San Pasqual
Band of Diegueño Mission Indians with the
project Cultural Reports on May 11, 2023.
The San Pasqual Band of Diegueño Mission
Indians requested inclusion of a Kumeyaay
monitor during construction in a letter to the
City on January 10, 2024. The City confirmed
a Kumeyaay monitor would be included in the
project’s conditions of approval, and the San
Pasqual Band of Diegueño Mission Indians
concluded AB 52 consultation on February
14, 2024. As of November 2, 2023, the City
2 Project Description
Hughes Circuits Project Environmental Impact Report March 2024 City of San Marcos 2-20
Table 2-2.
Summary of Changes to the Draft EIR
Section Original Text Proposed Change(s)
has not received a letter concluding
consultation.
Section 3.16.4,
Pursuant to AB 52, notification letters
were mailed by the City on May 3, 2022,
to California Native American Tribal
representatives (that have requested
notification) who are traditionally or
culturally affiliated with the geographic
area of the project. Three tribes
requested consultation under AB 52,
including the Rincon Band of Luiseño
Indians on May 20, 2022, San Luis Rey
Band of Mission Indians on June 6,
2022, and San Pasqual Band of Mission
Indians. The Rincon Band of Luiseño
Indians agreed with the mitigation
measures proposed by Dudek in the
archaeological resources report, which
includes archaeological and tribal
monitoring, and protocols for the
discovery of cultural material and
human remains. Additionally, the Rincon
Band of Luiseño proposed that if export
of soil is planned, consultation with the
affiliated tribes will have to be initiated,
and this was included in the mitigation
measures. The Rincon Band of Luiseño
concluded AB 52 consultation on
December 20, 2022. The San Luis Rey
Band agreed with the proposed
measures for tribal cultural resources
(MM-CUL-1 through MM-CUL-4) for the
project’s environmental document. The
San Luis Rey Band of Mission Indians
concluded AB 52 consultation on
January 12, 2023. The San Pasqual
Band of Mission Indians requested
consultation on May 11, 2023. The
Cultural Report was provided to San
Pasqual band of Mission Indians, and as
of November 2, 2023, the city has not
received a letter concluding
consultation. Therefore, consultation
with San Pasqual band of Mission
Indians has not yet been closed.
Pursuant to AB 52, notification letters were
mailed by the City on May 3, 2022, to
California Native American Tribal
representatives (that have requested
notification) who are traditionally or culturally
affiliated with the geographic area of the
project. Three tribes requested consultation
under AB 52, including the Rincon Band of
Luiseño Indians on May 20, 2022, San Luis
Rey Band of Mission Indians on June 6,
2022, and San Pasqual Band of Mission
Indians on May 11, 2023. The Rincon Band
of Luiseño Indians agreed with the mitigation
measures proposed by Dudek in the
archaeological resources report, which
includes archaeological and tribal monitoring,
and protocols for the discovery of cultural
material and human remains. Additionally,
the Rincon Band of Luiseño proposed that if
export of soil is planned, consultation with
the affiliated tribes will have to be initiated,
and this was included in the mitigation
measures. The Rincon Band of Luiseño
concluded AB 52 consultation on December
20, 2022. The San Luis Rey Band agreed
with the proposed measures for tribal cultural
resources (MM-CUL-1 through MM-CUL-4) for
the project’s environmental document. The
San Luis Rey Band of Mission Indians
concluded AB 52 consultation on January 12,
2023. The San Pasqual Band of Mission
Indians requested consultation on May 11,
2023. The City provided the San Pasqual
Band of Diegueño Mission Indians with the
project Cultural Reports on May 11, 2023.
The San Pasqual Band of Diegueño Mission
Indians requested inclusion of a Kumeyaay
monitor during construction in a letter to the
City on January 10, 2024. The City confirmed
a Kumeyaay monitor would be included in the
project’s conditions of approval, and the San
Pasqual Band of Diegueño Mission Indians
concluded AB 52 consultation on February
14, 2024. The Cultural Report was provided
to San Pasqual band of Mission Indians, and
as of November 2, 2023, the city has not
received a letter concluding consultation.
Therefore, consultation with San Pasqual
2 Project Description
Hughes Circuits Project Environmental Impact Report March 2024 City of San Marcos 2-21
When deciding whether to approve the project, the City will use the information provided in the Final EIR to consider potential impacts to the physical environment. The City will also consider all written comments received on the Draft EIR during the 45 -day public review period in making its decision to certify the Final EIR as complete and compliant with CEQA and in making its determination whether to approve or deny the project. Environmental considerations, as well as economic and social factors, will be weighed by the City to determine the most appropriate course of action.
Prior to approving the project, the City must make written findings and adopt a Statement of Overriding Considerations with respect to any significant and unavoidable environmental effect identified in the Draft EIR (14 CCR 15091, 15093). If the project is approved, the City will file a Notice of Determination with the State Clearinghouse and San Diego County Clerk within 5 working days after project approval (14 CCR 15094).
Subsequent to certification of the Final EIR, agencies with permitting authority over all or portions of the project may use the Final EIR ’s evaluation of the project ’s environmental effects in considering whether to approve or deny applicable permits.
2.4.5 Project Approvals and Permits
Consistent with the City ’s General Plan and San Marcos Municipal Code Zoning Ordinance Title 20, the project requires certain entitlements be submitted, reviewed, and approved by the Cit y. The requested entitlements include a Site Development Plan, which will present specific lot configurations for the site. The City will use this EIR and associated documentation in its decision to approve or deny the required discretionary permits. The City may also use this EIR in its consideration of any future development proposal, together with any additional or supplemental information or CEQA analysis as may be required. Other responsible and/or trustee agencies can use this EIR and supporting documentation in their decision -making process to issue additional approvals. These additional approvals may include, but are not limited to , approval of sewer and water connections, approval of sign permits, and approval of biological resources mitigation . Responsible agencies include the California Department of Fish and Wildlife, U.S. Fish and Wildlife Service, U.S. Army Corps of Engineers, and Regional Water Quality Control Board.
Table 2-2.
Summary of Changes to the Draft EIR
Section Original Text Proposed Change(s)
band of Mission Indians has not yet been
closed.
2 Project Description
Hughes Circuits Project Environmental Impact Report March 2024 City of San Marcos 2-22
2.5 PROJECT INCONSISTENCIES WITH APPLICABLE
REGIONAL AND GENERAL PLANS
Throughout Chapter 3 of this EIR, the project has been evaluated in relation to the applicable goals, policies, and objectives of the City’s General Plan and San Marcos Municipal Code Zoning Ordinance Title 20 (Section 3.10, Land Use); San Diego Forward: The Regional Plan (Section 3.10); Regional Air Quality Strategy (Section 3.2, Air Quality); San Diego Air Pollution Control District policies (Section 3.2); City’s Climate Action Plan (Section 3.7, Greenhouse Gas Emissions); Regional Water Quality Control Board plans and permits (Section 3.9, Hydrology and Water Quality); the Multiple Habitat Conservation Program (Section 3.3); Airport Land Use Compatibility Plans (Section 3.8, Hazards and Hazardous Materials; Section 3.10, Land Use and Planning ; and Section 3.11, Noise); and various other applicable regional and local plans and policies.
2.6 LIST OF PAST, PRESENT AND REASONABLY
ANTICIPATED FUTURE PROJECTS IN THE
PROJECT AREA
CEQA requires an EIR to analyze cumulative impacts. Section 15355 of CEQA Guidelines defines cumulative impacts as “two or more individual effects which, when considered together, are considerable or which compound or increase other environmental impacts.” Section 15130 of the CEQA Guidelines provides guidance for analyzing significant cumulative impacts in an EIR. The discussion of cumulative impacts “need not provide as great detail as is provided for the effects attributable to the project alone,” but in stead is to be “be guided by standards of practicality and reasonableness” ( CEQA Guidelines Section 15130[b]). The discussion should also focus only on significant effects resulting from the project ’s incremental effects and the effects of other projects.
According to Section 15130(a)(1), “an EIR should not discuss impacts which do not result in part from the project evaluated in the EIR.”
Cumulative impacts can result from the combined effect of past, present, and future projects located in proximity to the project under review. Therefore, it is important for a cumulative impacts analysis to be viewed over time and in conjunction with other related past, present, and reasonably foreseeable future developments whose impacts might compound or interrelate with those of the project under review.
According to Section 15130(b)(1) of the CEQA Guidelines, a cumulative impact analysis may be conducted and presented by either of two methods:
(A) a list of past, present, and probable activities producing related or cumulative impacts; or
(B) a summary of projections contained in an adopted general plan or related planning document, or in a prior environmental document that has been adopted or 2 Project Description
Hughes Circuits Project Environmental Impact Report March 2024 City of San Marcos 2-23
certified, which described or evaluated regional or area -wide conditions contributing to the cumulative impact.
With the exception of the impact analyses of air quality and greenhouse gas emissions, the cumulative list approach has been used in this cumulative analysis, as discussed below. The cumulative impacts of air quality and greenhouse gas emissions have been evaluated using the summary of projections method because the geographic scope of such impacts are on an air basin and global scale.
An inventory of past, present, and reasonably foreseeable future projects within the vicinity of the project site is presented in Table 2-1 and Figure 2-6, Cumulative Projects.
Table 2-31
Cumulative Projects
No. Status
Project
Name/Developer Location Description
City of San Marcos
1 Approved Block 3 Student
Housing
NW corner of Campus
Way and Barham Drive
342 bed student housing
development, with a
buildout year of 2022
2 Approved Discovery Village
North
Craven Rd. Office/Commercial/
Residential on 41 acres
3 Proposed Main Square SE corner of San
Marcos Blvd. & McMahr
Rd.
Mixed-use development
with a 468-units apartment
complex, and 44,007 SF of
commercial space
4 Approved San Elijo Hills San Elijo Rd. 11,711 SF Commercial development with a
buildout year of 2022
5 Under Construction Pacific
Commercial
NE corner of Grand Ave.
& Pacific St.
122 room hotel, with a
buildout year of 2022
6 Under Construction San Marcos
Highlands
North end of N. Las
Posas Rd.
187-unit Single-Family
Residential development,
with a buildout year of
2023
7 Under Construction Villa Serena-
Phases 1 and 2
Richmar Ave. & Marcos
St.
Demolition of 136 units and
construction of 148 unit
apartment complex, with a
buildout year of 2023 for
Phase 1 and 2024 for
Phase 2
8 Approved Montiel Rd
Partners
Montiel Rd. 8-unit Single-Family
Residential development,
with a buildout year of
2024
9 Approved Meadowlark
Canyon LLC
San Marcos Blvd. 33-unit Single-Family
Residential development
2 Project Description
Hughes Circuits Project Environmental Impact Report March 2024 City of San Marcos 2-24
Table 2-31
Cumulative Projects
No. Status
Project
Name/Developer Location Description
10 Under Construction Mariposa- Phase
1 (Alora)
Richmar Ave. & Los
Olivos Dr.
60-unit apartment complex,
with a buildout year of
2023
11 Approved Mariposa- Phase
2 (Estrella)
Richmar Ave. & Los
Olivos Dr.
66-unit apartment
development with a
buildout year of 2024
12 Under Construction Murai-Sab N. Las Posas Rd. 89-unit Single-Family Residential with a buildout
year of 2022/2023
13 Under Construction Pacifica San
Marcos
S. Rancho Santa Fe Rd
& Creek St.
Mixed use development of
31-unit apartment complex
and 4,375 SF commercial
space with a buildout year
of 2022/2023
14 Under Construction Discovery Village
South
Future Discovery St. 220-unit Single-Family
Residential, with a buildout
year of 2023
15 Approved Breaker Real
Estate
SE corner of Twin Oaks
Valley Rd & Richmar
Ave.
174 bed Assisted Living
Facility with a buildout year
of 2024
16 Approved Hall Land
Company
Barham Drive, east of
Woodland Pkwy.
151-unit multifamily
condominium development
with buildout year of 2024
17 Approved Southlake Park
Phase 1
Twin Oaks Valley Rd,
South of Village Dr
Parking Lot, Fishing Dock
18 Approved MacDonald
Group
San Marcos Blvd.
(Former Sears site)
Mixed-use development
with 82-unit apartment
complex and 5,000 SF of
commercial space with a
buildout year of
2023/2024
19 Proposed SP 2017-0004 -
Lanikai
Mission Rd at
Woodward St (west side)
115-unit Senior Living
Complex
20 Under Construction Sunrise Barham Drive (near east
City limit)
192 dwelling unit Multi-
Family Condominiums with
a buildout year of 2023
21 Under Construction Jump Ball LLC NWC of San Marcos
Blvd. at Bent Ave.
Drive-thru Restaurant with
buildout year of 2023
22 Approved Montiel
Commercial
2355/2357 Montiel Rd. 32,971 SF Office building
23 Approved California
Allstars
East side of Twin Oaks
Valley Rd.
28,137 SF Industrial
Building to be completed in
2022
2 Project Description
Hughes Circuits Project Environmental Impact Report March 2024 City of San Marcos 2-25
Table 2-31
Cumulative Projects
No. Status
Project
Name/Developer Location Description
24 Proposed Budhi Hill
Buddhist Center
Poinsettia Ave. s/o
Linda Vista Dr.
Development of a 44,113
SF Place of Assembly and
associated camous
25 Proposed Mercy Hill and
Marian Center
Borden Rd 31,105 SF Christian Center
26 Approved Karl Strauss
Brewery
Las Posas Rd & Los
Vallecitos Blvd.
10,528 SF Tasting Room,
Commercial Kitchen,
Entertainment Room within
existing commercial
building
27 Approved Kiddie Academy Twin Oaks Valley Rd,
northeast of Windy Way
11,430 SF Preschool with a
buildout year of 2022
28 Proposed Edenpark 1601 San Elijo Road Adaptive reuse of existing structures for recreation,
sports, and related personal
services, and related
commercial uses
29 Under Construction San Marcos
Creek Phase 1
CIP - various
numbers
Via Vera Crux Bridge,
Bent Avenue Bridge,
Discovery
Street widening, Levee
construction,
Promenade, and Creek
Channel Wetland
Restoration.
San Marcos Creek Phase 1
Infrastructure, Discovery
Street (east/west segment),
Bent Avenue to Discovery
Street (north/south
segment) with a buildout
year of 2024
30 Funded CIP 88179 Smilax Road/South
Santa Fe Avenue
Intersection re-
alignment
Smilax Road/South Santa
Fe Avenue Intersection re-
alignment with a buildout
year of 2023
31 Under Construction CIP 86002 San Marcos Boulevard
at Discovery Street
Intersection
Intersection improvement
300 feet west, and 920
feet east, of intersection
with a buildout year of
2023
32 Under Construction PARK CIP Rancho Tesoro Park
Improvements – 6.5
acres of 41 acre park
City Park – Phase 1 Multi-
Use Field and Parking Lot
Improvements with a
buildout year of 2022
33 Programmed CIP ST005 San Marcos Boulevard
Reconstruction
Street signal upgrades from
Rancho Sante Fe to Grand
Avenue with a buildout year
of 2026.
34 Proposed SP 22-0001
Pacific Specific
Plan
Generally located at the
northwest corner of S.
Las Posas Road and
Linda Vista Drive
449-unit multi-family
residential development on
33.2 acres.
2 Project Description
Hughes Circuits Project Environmental Impact Report March 2024 City of San Marcos 2-26
Table 2-31
Cumulative Projects
No. Status
Project
Name/Developer Location Description
35 Approved Pacific Grand
Ventures, LP
East side of Pacific
Street, north of Grand
Avenue
26,156 SF industrial
building.
36 Proposed Twin Oaks Valley
Winery
1451 Mulberry Dr 3,121 square foot 2-story
winery and tasting room on
a 4.23-acre lot
37 Approved Grand Vista/CCI West side of Los Posas
Road and Palm Road
120-unit residential
condominium development.
38 Approved Paul Mayer-
Santa Fe Las
Floras LP
Northwest corner of S.
Santa Fe Ave and Las
Flores Drive
50-unit residential
apartment building.
39 Proposed Water Mill
Homes, Inc.
(Manning
Homes)
SW corner of Mulberry
Dr. and Cox Rd.
9 single-family residential
lots on a 10-acre property.
40 Proposed San Marcos
Hospitality
SW corner of Montiel
Rd. and Leora Ln.
Hotel with 107 rooms.
41 Approved Lonnie Tavvaa –
Arco
200 Las Posas Rd. Gas station, convenience
store, car wash.
42 Proposed TPM 21-0001
Woodward Lot
Split
South of Woodward St.
at Killarney Terrace.
3 single-family residential
lots.
43 Proposed SH North City,
LLC
Discovery St. west of S.
Twin Oaks Valley Rd.
532 attached and 94
detached condo units (626
total units), master
association community rec
center, public and private
trail systems that connect
to future Knoll Park.
44 Approved University
District Specific
Plan
Amendment –
North City Ph. A
& B
UniveristyUniversity
District Specific Plan -
N.E. of North City Drive
and Campus Way
Mixed use development
with 20,000 SF of retail,
100,000 SF of office, and
537 multi-family residential
units with a buildout year of
2025.
45 Approved American
Rentals
1030 Linda Vista Dr. 2,500 SF of equipment
rental facility with a
buildout year of 2023
46 Proposed P17-0020 (SDP
17-005) Hunter
Industries
West terminus of Opal
Dr.
67,657 SF office building
47 Proposed SDP 22-0002-
Hughes SMCC,
LLC
NE corner of Pacific St,
approximately 750 ft
south of Linda Vista Dr.
67,410 SF industrial
building.
2 Project Description
Hughes Circuits Project Environmental Impact Report March 2024 City of San Marcos 2-27
Table 2-31
Cumulative Projects
No. Status
Project
Name/Developer Location Description
48 Approved SP 22-0003 -
Marcos Specific
Plan
SW corner of Grand Ave
and Linda Vista Dr
Horizontal mixed-use
project with 102 residential
units and 63,641 SF of
commercial space and 8
live/work units.
49 Proposed Polley
Apartments
North side of Polley
Drive at the eastern
terminus
17-unit apartment building
on a 0.60-arce
undeveloped lot.
50 Proposed Salim Mixed-Use
Development
South side of San
Marcos Blvd,
approximately 300 feet
west of Via Vera Cruz.
Mixed-use development on
4.8 acre lot with 10,067 SF
of commercial space, 250
residential units, and 8
live/work units.
51 Proposed Lennar Homes
of California, LLC
1020-1080 W. San
Marcos Blvd.
Mixed-use development
with 10,400 SF of
commercial space, 202
residential condominium
units, and a public park
52 Approved San Elijo Hills
Town Center
East
1093 San Elijo Road Two-story, multi tenant
8,026 SF commercial
building
53 Approved SDP22-0004 -
Creekside Pad M
573 Grand Avenue 5,400 SF multi-tenant retail
building in commercial
center
54 Proposed TPM22-0003 -
Marilyn Lane 3-
Lot Split
1821022500 &
1821023100
3-lot split for Single Family
Residential Lots.
55 Proposed GPA 22-0003 -
Capalina
Apartments
Capalina Rd. 219-115-
33-00
Construction of a mixed-use
project on a vacant lot
consisting of 119
residential units and 4,000
SF of commercial.
56 Proposed CUP23-0001 -
San Elijo Hills
Building F LLC
Lot 3 of Parcel Map
#16344
6,400 SF preschool
57 Proposed SP22-0005 -
Woodward 46
East side of Woodward
St, north of Mission Rd.
46-unit Residential
Condominium Development
58 Approved GPA22-0005 -
Pico
Investments
236 Pico Avenue 16-unit Residential
Condominium Development
59 Proposed SPD22-0009 -
CRP III Mission,
LLC
528 W. Mission Road Redevelop an existing
10.83-acre industrial park
with 3 new industrial
buildings totalling 132,310
SF.
2 Project Description
Hughes Circuits Project Environmental Impact Report March 2024 City of San Marcos 2-28
Table 2-31
Cumulative Projects
No. Status
Project
Name/Developer Location Description
60 Proposed SP23-0001 -
Armorlite Lofts
Vacant lot on the north
side of Armorlite Drive,
in the 1200 block
165 residential apartment
units and 5,600 SF of
commercial space with a
buildout year of 2025.
61 Proposed SDP23-0001
Pardis
Apartments
South side of San
Marcos Blvd,
approximately 175 feet
east of Via Vera Cruz.
Mixed-use development on
a 0.92-acre lot consisting of
41 residential units and
2,980 SF of commercial
space
62 Proposed SDP23-0002 2236510100 83,800 SF, 84-unit, 116 resident residential care
facility for Alzheimer’s and
Memory Care
63 Proposed CUP23-0004
Costco
150 S. Bent Avenue Gas station with 15 multi-
fuel dispensors
CUP = Conditional Use Permit
du = dwelling unit
GPA = General Plan Amendment
MFR = multi-family residence
MUP = Major Use Permit
REZ = Rezone
S = Site Plan
SCH = State Clearinghouse
SF = square feet
SP = Specific Plan
SPA = Specific Plan Amendment
SFR = single-family residence
TM = Tentative Map
TPM = Tentative Parcel Map
VTM = Vesting Tentative Map
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SOURCE: USGS 7.5-Minute Series San Marcos Quadrangle
T ownship 12S / Range 3W / Section 16
02 , 0 0 0 1,000
Feet
Project Site
Impact Footprint
FIGURE 2-1
Chula Vista
Solana Beach
Encinitas
San Diego
Carlsbad
Oceanside
Lemon Grove
La Mesa
El Cajon
Santee
Poway
San
Marcos
Escondido
Vista
Imperial Beach
National City
Del Mar
Coronado
Riverside
County
Mexico
Pacific Ocean
SAN DIEGO
COUNTY
Project Site
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0 200100
Feetn
Project Boundary
Impact Footprint
Offsite Impact Footprint
San Diego County Water
Authority Right of Way
FIGURE 2-2
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WQ BASIN WQ BASIN
TRASH
ENCLOSURE
PATIO
APN 219-210-29
BRADLEY PARK
PROPOSED BUILDING
S. PACIFIC STREET
S. PACIFIC STREET
RW RW
PL PL
RW RW
PL PL
RW
RW
RW RW
2:1 MAX
2:1 MAX 2:1
2:1 2:1
2:12:1
RW
RW
Feet
02 0 4 0
SCALE 1":20'
MATCHLINE SEE LEFT FOR CONTINUATION
Site Plan
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FIGURE 2-3
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SPA
OS
I
MU3
LI
PI C
Existing General Plan Land Use
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0 200 100
Feet
Project Boundary
General Plan Land Use
C, Commercial
I, Industrial
LI, Light Industrial
MU3, Mixed Use 3
OS, Open Space
P, P a r k s
PI, Public/Institutional
SPA, Specific Plan Area (San Marcos Creek)
FIGURE 2-4
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I
P
SPA
I
OS
I
MU3
LI
LI
PI C
Existing Zoning
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0 200 100
Feet
Project Boundary
Zoning
C & I / MU-3, C & I / MU-3
C, Commercial
I / L-I, I / L-I
I, Industrial
L-I, Light Industrial
MU-3, Mixed Use-3
O-S, Open Space
P-I, Public-Institutional
SPA, Specific Plan Area (San Marcos Creek)
FIGURE 2-5
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05 , 9 0 0 2,950
Feet
City of San Marcos
Project Site
Other San Marcos Development Project Locations
FIGURE 2-6
Project Site
Hughes Circuits Project Environmental Impact Report March 2024 City of San Marcos 2-40
INTENTIONALLY LEFT BLANK
Hughes Circuits Project Environmental Impact Report March 2024 City of San Marcos 3.1-1
3 ENVIRONMENTAL ANALYSIS
3.1 AESTHETICS
This section describes the existing visual setting of the Hughes Circuits Project (project) and vicinity, identifies associated regulatory requirements, evaluates potential impacts, and identifies mitigation measures related to implementation of the project.
Table 3.1-1 summarizes the project and cumulative level aesthetics impacts, by threshold.
Table 3.1-1
Aesthetics Summary of Impacts
Threshold of Significance
Project-Level
Impact
Cumulative-
Level Impact
Significance
Determination
#1 – Have a substantial adverse impact on a scenic
vista.
Less than
Significant
Less than
Significant
Less than
Significant
#2 – Substantially damage scenic resources, including
but not limited to trees, rock outcroppings, and historic buildings within a state scenic highway.
No Impact No Impact No Impact
#3 – In non-urbanized areas, substantially degrade the
existing visual character or quality of public views of the site and its surroundings? (Public views are those
that are experienced from publicly accessible vantage
point). If the project is in an urbanized area, would the project conflict with applicable zoning and other
regulations governing scenic quality?
Less than
Significant
Less than
Significant
Less than
Significant
#4 – Create a new source of substantial light or glare
which would adversely affect day or nighttime views in
the area.
Less than
Significant
Less than
Significant
Less than
Significant
3.1.1 Existing Conditions
3.1.1.1 Existing Visual Resources and Environment
Scenic Highways
According to the California Department of Transportation California Scenic Highway Mapping System, the project site is not located adjacent to , or in the vicinity of , a designated state scenic highway (Caltrans 2022). The nearest officially designated state scenic highway is State Route (SR) 78. SR-78 is a designated state scenic highway from the west boundary of the Anza-Borrego Desert State Park to the east boundary of the State Park. SR-78 is located approximately 0.7 miles north of the project site; however, the portion designated as a state scenic highway begins approximately 41 miles east of the project site. The project site is located approximately 26 miles west of the closest portion of SR -78 identified as an eligible state scenic highway.
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SR-52 is a designated state scenic highway from the west boundary of the Mission Trails Open Space to the east boundary of Little Sycamore Canyon . The portion designated as a state scenic highway SR-52 is located approximately 21 miles south of the project site . The nearest eligible state scenic highway is Interstate 5. The project site is approximately 6.8 miles east of the closest point of thi s eligible state scenic highway.
At a local level, the City of San Marcos (City) has designated SR -78 as a view corridor for its unobstructed visual passageway. The highway corridor provides views of the Merriam Mountains, little Mt. Whitney, Double Peak, California State University San Marcos , and Palomar Community College.
Views of the project site from SR-78 are generally obscured from the view of motorists due to existing commercial and residential developments.
Scenic Vistas
A scenic vista is typically defined as a panoramic view or vista from an identified view/vista point, public road, public trails, public recreational areas, or scenic highways. Potential scenic views from private properties are not under consideration in this analysis, as it is not required by the City. The City’s General Plan does not identify any designated scenic vistas; however, the General Plan more generally aims to protect the City’s scenic resources such as the San Marcos, Merriam, and Double Peak Mountains, creek corridors, mature trees, rock outcroppings, and ocean views (City of San Marcos 2012). The project site is surrounded by urban development areas. Potential vanta ge points in the City include little Mt. Whitney and Franks Peak, located approximately 3 miles southeast of the project site. There is a potential for the project site to be visible from the little Mt. Whitney peak; however, this peak is accessible only by a private road and peak access is prohibited to the public. The Franks Peak summit is accessible by various public recreational trails, which could serve as potential vantage points of the project site. Views of the project site from Franks Peak and associated trails would be partially obstructed by little Mt. Whitney. Double Peak is also a prominent landform with long and broad views located approximately 2 miles southeast of the project site; however, views of the project site from Double Peak are entirely obstructed by various ridgelines.
Visual Character
The following is a description of the existing visual characteristics and quality of the project site and surroundings.
Project Site
The approximately 10.46-acre project site is vacant land that consists of Assessor’s Parcel Numbers 219-223-20-00 and 219-223-22-00. The project site sits north of South Pacific Street on one side and east of South Pacific Street on the other. Adjacent land uses include mixed commercial development to the north and south, a public recreational park (Bradley Park) to the west, and undeveloped land to
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the east. The project location and project site boundary are shown in Figures 2-1 and 2-2. The project site is immediately visible from adjacent streets and surrounding land uses.
The project site is characterized by undeveloped terrain and has no existing impervious areas. The topography within the project site is relatively flat with multiple wetlands and vegetation communities throughout; additionally, a parcel owned by the San Diego County Water Authority right-of-way as well as a dirt walking path bisect the site. Elevation ranges from approximately 520 feet above mean sea level in the eastern portion of the project site to 535 feet above mean sea level in the northwest portion of the project site.
The undeveloped project site contains 16 vegetation communities and/or land covers were identified and categorized into three community subgroups: sensitive uplands, sensitive wetlands/riparian habitat, and non-sensitive uplands. Sensitive uplands within the review area consist of Diegan coastal sage scrub, Diegan coastal sage scrub-Baccharis dominated, non-native grassland-artichoke-thistle dominated, non- native grassland -broadleaf dominated, valley needle grassland, and wildflower fields. Sensitive wetlands/riparian habitats within the review area include Arundo-dominated riparian habitat, disturbed wetlands, emergent wetlands, San Diego Mesa claypan vernal pools, southern willow scrub, and Tamarisk scrub. Non-sensitive uplands consist of disturbed habitat and Eucalyptus woodland. Please refer to Section
3.3 of this environmental impact report (EIR) for a detailed analysis of biological resources.
Surrounding Area
The project site is immediately bordered by South Pacific Street to the west and south, vacant land to southeast, and Light Industrial properties to the north. The project site is surrounded by Light Industrial developments to the north , Commercial developments to the northeast, Industrial developments to the south, and a park to the west. Residential uses are located to the southwest of the site, south of the park. The project site is located in an urban setting and is considered an infill site. The closest freeway is SR-78, located approximately 0.7 miles north of the project site.
The existing Light Industrial developments to the north of the project site and the existing Industrial developments to the south of the project site, are characterized by one to two story buildings with white or tan smooth exteriors. The existing Commercial development to the northeast is a local mall that consists of various retail department stores and restaurants. These buildings are one to two story buildings with tan or white exteriors and with grey brick accents. The existing park to the east of the project site is Bradley Park, which is located at 1587 Linda Vista Drive and contains an arena soccer field, a ballfield, BBQs, a horseshoe court, a multi-purpose field, picnic shelters, picnic tables, and play equipment.
Existing Light and Glare Conditions
The project site is currently undeveloped and thus does not contain any existing sources of light or glare, with the exception of a streetlight on the southwest corner of the project site illuminating South
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Pacific Street. Additionally, the project site does not contain any reflective surfaces that would act as sources for glare. Commercial and industrial developments surrounding the project site contain sources of light ing typical of these land uses . Sources of nighttime lighting in this area could occur from exterior building lighting, street lighting, and lighting in parking lots. No sources of substantial glare are present in this area.
3.1.2 Regulatory Setting
State
California Public Resources Code Section 20199
California Public Resources Code Section 20199 (d)(1) stipulates that “aesthetic and parking impacts of a residential, mixed -use residential, or employment center project on an infill site within a transit priority area shall not be considered significant impacts on the environment.” The project does not propose a residential use, mixed -use residential, or an employment center on an infill site. This is further addressed in Section 3.1.4, Project Impact Analysis, below.
California Scenic Highway Program
The California State Legislature created the California Scenic Highway Program in 1963 with the intent “to protect and enhance the natural scenic beauty of California highways and adjacent corridors, through special conservation treatment.” The state laws that govern the Scenic Highway Program are Sections 260 through 263 of the Streets and Highways Code. A highway may be designated scenic based on the natural landscape visible by travelers, the scenic quality of the landscape, and the extent to which development intrudes upon the views of the highway. The Scenic Highway Program includes both officially designated scenic highways and highways that are eligible for designation. A highway may be designated as scenic based on aesthetic quality of viewable landscape, extent of views upon the natural landscape, and the degree to which development impedes these views. It is the responsibility of local jurisdictions to apply for scenic highway approval, which requires the adoption of a Corridor Protection Program (C altrans 2022). There are no state -designated scenic highways in the vicinity of the project site.
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Local
City of San Marcos General Plan
The City’s Conservation and Open Space Element identifies one goal and associated policies to protect natural resources that have scenic value. Landforms such as the mountain ranges in the northern and southern portions of the City contribute to its scenic corridors. The following goal and policies from the City of San Marcos General Plan, Conservation and Open Space Element pertain to aesthetics and visual quality (City of San Marcos 2012):
• Goal COS -3: Protect natural topography to preserve and enhance the natural beauty of San Marcos.
o Policy COS-3.1: Preserve scenic resources, including prominent landforms such as Double Peak, Owens Peak, San Marcos Mountains, Merriam Mountains, Cerro de Las Posas, Franks Peak, and canyon areas through conservation and management policies. o Policy COS -3.2: Encourage and maintain high -quality architectural and landscaping designs that enhance or complement the hillsides, ridgelines, canyons, and view corridors that comprise the visual character in San Marcos.
o Policy COS -3.3: Continue to work with new development and redevelopment project applicants in designing land use plans that respect the topography, landforms, view corridors, wildlife corridors, and open space that exists. o Policy COS-3.4: Evaluate potential impacts to visual and aesthetic resources, including the potential to create new light sources, while still maintaining and being sensitive to rural lighting standards.
The project’s consistency with applicable General Plan goals and policies is discussed in Section 3.10, Land Use and Planning. As detailed in Section 3.10.4, the project is consistent with the applicable goals and policies pertaining to aesthetics.
San Marcos Municipal Code Zoning Ordinance, Title 20
The provisions of Title 20 of the San Marcos Municipal Code are referred to as the Zoning Ordinance.
The San Marcos Municipal Code Zoning Ordinance Title 20 is the primary implementation tool for the policies of the General Plan. The Zoning Ordinance provides more detailed direction related to design and development standards; permitted, conditionally permitted, and prohibited uses; and other regulations such as lighting and sign regulations. The land uses specified in the Zoning Ordinance are based upon and consistent with the land use policies set forth in the General Plan. Specifically, building design, setbacks, lighting, and signage standards as well as open space requirements for development to protect open space and ambient light levels in the City. Lighting standards of the Ordinance require
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energy-efficient lighting that limits light and glare for private projects, with exceptions for specialized streetscape lighting. Private developments are required to submit lighting plans to ensure consistency with dark sky needs of the region (City of San Marcos 2022).
Title 20, Section 20.300.080, Site Planning and General Development Standards The City of San Marcos Street Lighting Standards and Specifications describes the lighting and glare standards for the City. These standards require lighting to be directed downward and limit the type and spacing of lighting to maintain reasonable lighting levels that do not contribute to light pollution.
The City uses International Dark Sky Association (IDA) thresholds to inform its own testing, leading to a policy that allows for the use of energy-efficient lighting sources that include, but are not limited to, LED and induction lighting technologies (City of San Marcos 2022).
Title 20, Chapter 20.260, Ridgeline Protection and Management Overlay Zone The City of San Marcos adopted a Ridgeline Protection and Management Overlay Zone in November 2008, set forth in Ordinance 2008 -1314, to minimize visual impacts to important ridgelines. These guiding principles are in place to protect natural viewsheds, minimize physical impacts to ridgelines, and establish innovative site and architectural design standards. The Ordinance identifies primary and secondary ridgelines within the City, plus buffer zones, or Ridgeline Overlay Zones (ROZ), surrounding these ridge lines (City of San Marcos 20 22). No primary or secondary ridgelines are located within or adjacent to the project site; the nearest ridgeline is a secondary ridgeline located approximately 1.2 miles west of the project site. The nearest primary ridgeline is located approximately 1.7 miles southwest of the project site.
3.1.3 Thresholds of Significance
The significance criteria used to evaluate the project impacts to aesthetics are based on Appendix G of the California Environmental Quality Act ( CEQA) Guidelines. According to Appendix G of the CEQA Guidelines, a significant impact related to aesthetics would occur if the project would:
• Threshold #1: Have a substantial adverse effect on a scenic vista. • Threshold #2: Substantially damage scenic resources, including, but not limited to trees, rock outcroppings, and historic buildings within a state scenic highway. • Threshold #3: In non-urbanized areas, substantially degrade the existing visual character or quality of public views of the site and its surroundings. (Public views are those that are experienced from publicly accessible vantage point). If the project is in an urbanized area, would the project conflict with applicable zoning and other regulations governing scenic quality? • Threshold #4: Create a new source of substantial light or glare which would adversely affect day or nighttime views in the area.
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3.1.4 Project Impact Analysis
As described in Chapter 2 , Project Description, of this EIR, the project consists of development of a 67,410-square-foot light industrial building to support the expansion of the existing operations of Hughes Circuits Inc., currently located adjacent to the project site to the south, at 546 S. Pacific Street.
The 67,410 -square-foot light industrial building includes a 56,310 -square-foot first floor, and a 11,100-square-foot mezzanine. The proposed light industrial building would be located at the western- most portion of the project site, and the disturbance area associated with project construction would be limited to approximately 113,877 square feet or 2.61 acres of the 10.46-acre project site. Proposed development would only occur within Assessor’s Parcel Number 219-223-20-00. The proposed light industrial building would include a fire control room, MPOE room, trash enclosure, outdoor amenity area, electrical room, and grade level loading dock. Parking for the pro posed building would include 72 parking spaces, including 4 electric vehicle charging stations, 9 carpool and zero emission parking stalls, 4 accessible stalls, and 1 U .S. Postal Service parking stall. Additionally, 4 short -term bicycle parking spaces and 4 long -term bicycle parking spaces would be provided. Access to the proposed building would be provided via two new driveways along S. Pacific Street, one at the northwestern boundary of the proposed building site, and the other at the southeastern boundar y of the proposed building site, as shown in Figure 2-3, Site Plan. Stormwater basins and associated landscaping would be incorporated along the perimeter of the proposed light industrial building. Approximately 60 employees would work out of the proposed light industrial building.
The project site is currently designated as Light Industrial (LI) under the City’s General Plan Land Use Map and has a zoning designation of Light Industrial (L-I). The project proposes a light industrial land use, consistent with the City’s land use designations for the project site.
The project site is considered an infill site within an urbanized area under CEQA, but is not located within a transit priority area such that aesthetic impacts are conclusively not significant under California Public Resources Code (PRC) Section 20199 (d)(1). As described in Section 3.1.2 , Regulatory Setting, above, PRC Section 20199 (d)(1) states that “aesthetic and parking impacts of a residential, mixed-use residential, or employment center project on an infill site within a transit priority area shall not be considered significant impacts on the environment.” According to this same section at Section 21099(d)(1), an “infill site” is defined as “a lot located within an urban area that has been previously developed, or on a vacant site where at least 75 percent of the perimeter of the site adjoins, or is separated only by an improved public right-of-way from, parcels that are developed with qualified urban uses.” The project site is located on a vacant lot and more than 75% of the project boundary is adjacent to “qualified urban uses” (i.e., residential and commercial) per PRC Section 21072, such that the site is an “infill site.”
PRC Section 21071 defines an “urbanized area” as “(a) an incorporated city that meets either of the following criteria: (1) Has a population of at least 100,000 persons, or (2) Has a population of less
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than 100,000 persons if the population of that city and not more than two contiguous incorporated cities combined equals at least 100,000 persons.” As of 202 0, the City of San Marcos has an estimated population of 9 4,833 (see Section 3.12, Population and Housing ) (U.S. Census Bureau 2021a). While this is less than 100,000 persons, the City of San Marcos is contiguous with the City of Escondido, which has an estimated population of 151,038 persons as of 2020 (U.S. Census Bureau 2021b). The combined estimated population of these two contiguous cities would be 248,834 persons, which is well over the 100,000 persons threshold. Thus, the City of San Marcos would be considered an urbanized area per CEQA.
A “transit priority area” is defined as “an area within one-half mile of a major transit stop that is existing or planned.” The nearest major transit stop is North County Transit District’s Palomar College Station, located approximately 0.9 miles from the North County Transit District’s Palomar College Station, and therefore just outside of the transit priority area. Additionally, the project does not propose a residential use, mixed-use residential, or an employment center on an infill site.
Threshold #1: Would the project have a substantial adverse effect on a scenic vista? The City’s General Plan does not identify any designated scenic vistas; however, the General Plan more generally aims to protect the City’s scenic resources such as the San Marcos, Merriam, and Double Peak Mountains, creek corridors, mature trees, rock out croppings, and ocean views. The project site and surrounding valley terrain are encompassed by mountains to the north, east, and south that provide opportunities for elevated vantage points offering long and broad views, which may include views of the project site. However, due to the relatively flat terrain of the project site and surrounding area, and the project site’s location on an infill site in an urbanized area, development of the project is not expected to impede views of existing scenic vistas, nor is the project site considered a scenic vista. Therefore, impacts related to aesthetic impacts are considered less than significant.
Threshold #2: Would the project substantially damage scenic resources, including, but not limited to trees, rock outcroppings, and historic buildings within a state scenic highway? The nearest officially designated state scenic highway is SR -52. The portion designated as a state scenic highway SR-52 is approximately 21 miles south of the project site. The nearest eligible state scenic highway is Interstate 5. The project site is located approximately 6.8 miles east of the closest point of this eligible state scenic highway. SR-78 is 0.64 miles north of the project site. However, the section of SR-78 proximate to the project site is not identified as a Scenic Highway per the California Department of Transportation ( Caltrans) State Scenic Highways Program, although the City has designated SR-78 as a view corridor to surrounding ridgelines. Therefore, the project site is not located within a viewshed of a state scenic highway.
Additionally, a portion of SR -78 is also identified as an Eligible State Scenic Highway; however, this eligible segment begins 42 miles east of the project site in Santa Ysabel. As described above, views
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of the project site from SR -78 are generally limited due to existing industrial and commercial developments. Even with development of the project, views of the surrounding hillsides and ridgelines would not be substantially obstructed from SR-78.
Further, the project site is currently undeveloped and does not support any historic buildings. There are also no rock outcroppings on site. The project site contains on-site trees that would be removed during construction; however, these trees are ornamental and are not considered a scenic resource.
Therefore, implementation of the project would not substantially damage scenic resources within a state scenic highway, and no impact would occur.
Threshold #3: Would the project, i n non-urbanized areas, substantially degrade the existing visual character or quality of public views of the site and its surroundings ? (Public views are those that are experienced from publicly accessible vantage point). If the project is in an urbanized area, would the project conflict with applicable zoning and other regulations governing scenic quality? As previously discussed, the City of San Marcos (which includes the project site) is considered an urbanized area pursuant to PRC Section 21071. Therefore, the first question of Threshold #3 does not apply to the project, as it is directed at non-urbanized areas.
The visual character of the site would be altered by the project, from vacant and undeveloped land to industrial development. While the project would change the existing visual character on the site, it is not characterized as a substantial degradation since few public vantage points of the project site exist and the site is predominately surrounded by adjacent development in a highly urbanized area . The project would not alter the existing visual character of the surrounding area and would conform to the existing urbanized character of the surrounding area and w ould not substantially change the views from any public viewpoint. Additionally, a landscape plan would be implemented that would soften the visual impact of the proposed industrial development from adjacent roadways and land uses . The landscape plan to be prepared for the project would require review and approval by City staff. As the project would not substantially degrade the existing visual character or quality of the site and its surroundings, impacts are considered to be less than significant.
Threshold #4: Would the project create a new source of substantial light or glare which would adversely affect day or nighttime views in the area?
Lighting
Lighting in the project vicinity is associated with roadway lighting and lighting associated with the existing industrial and commercial uses that surround the project site. Development of the project would result in new sources of light from the light industrial building, landscaping lighting, security lighting, and internal circulation lighting. These proposed land uses would introduce lighting to a site that is currently undeveloped and has no existing source of lighting.
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All lighting associated with the project would be required to comply with the City’s Municipal Code Section 20.300.080, Light and Glare Standards. Although the project would result in new sources of light in the area, the project site is in a n urbanized area and is surrounded by existing development with existing sources of day and nighttime lighting. Compliance with the City’s Municipal Code would minimize and restrict nighttime light pollution and light trespass on adjacent properties. Therefore, new sources of day or nighttime lighting associated with the project would not be considered substantial, and impacts related to lighting would be considered less than significant.
Glare
Implementation of the project could potentially include sources of glare from architectural finishes or amenities on site. The project developer would be required by the City’s Municipal Code Section
20.300.080, Light and Glare Standards, to minimize use of reflective building materials and finishes, as well as reflective lighting structures , photovoltaic panels, and metallic surfaces to the extent feasible to impede any potential-generated glare. The project would incorporate materials and finishes that would minimize the potential for glare, including set back windows, window awnings, and neutral colors for building facades. The project would not propose any features that would be characterized as creating a substantial new source of glare that would adversely affect daytime or nighttime views in the area. Project impacts related to glare would be considered less than significant.
3.1.5 Cumulative Impact Analysis
Projects contributing to a cumulative aesthetic impact include those within the project viewshed. The viewshed encompasses the geographic area within which the viewer is most likely to observe the project and surrounding uses. Typically, this is delineated based on topography, as elevated vantage points, such as from scenic vistas, offer unobstructed views of expansive visible landscapes.
Cumulative aesthetic impacts would occur if projects combine to result in substantial adverse impacts to the visual quality of the environment and increase sources of lighting and glare. As discussed above, the project would have no substantial impact on a scenic vista or City protected scenic resource, would not adversely impact the visual character of the area, and would not introduce a substantial new source of lighting or glare.
Although not technically designated scenic vistas, little Mt. Whitney, Franks Peak, and the adjacent prominent ridgelines are scenic resources, which the City’s General Plan aims to protect and preserve for their natural visual quality. As previously discussed, the summit of little Mt. Whitney is off limits to the public, but Franks Peak and its surrounding recreational trails are publicly accessible. From Franks Peak, viewers would be able to see cumulative residential projects in the same viewshed , and potentially portions of the project site. The project would not substantially contrast with the visual patterns of the area as height and density would be consistent with the existing surrounding
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development and appear as an extension of the already urbanized landscape. Therefore, the project would not substantially contribute to a cumulative change in visual character of the surrounding area.
As discussed, the nearest officially designated state scenic highway is SR-52. The portion designated as a state scenic highway SR -52 is approximately 21 miles south of the project site. The nearest eligible state scenic highway is Interstate 5. The project site is located approximately 6.8 miles east of the closest point of this eligible state scenic highway. SR-78 is located 0.64 miles north of the project site. However, the section of SR-78 proximate to the project site is not identified as a Scenic Highway per the Caltrans State Scenic Highways Program, although the City has designated SR -78 as a view corridor to surrounding ridgelines. Therefore, the project site is not located within a viewshed of a state scenic highway.
As previously described, the project site is surrounded by existing developments that contain sources of lighting typical of industrial, commercial, and residential uses. The project would introduce new sources of lighting to the project site as the project would allow for the development of industrial uses. The project site is currently undeveloped and contains no sources of light. The project and cumulative projects would have to comply with the City’s Municipal Code, which would restrict light trespass into adjacent properties and ensure that new sources of lighting would not result in significant impacts . Concerning glare, implementation of the project would introduce PV panels on building rooftops, which could result in the potential for new sources of glare; however, panels are expected to be situated to avoid any potential for substantial glare to the surrounding area. The project developer, and the developers of any proposed cumulative projects would be required to minimize use of reflective building materials and finishes, as well as reflective lighting structures and metallic surfaces to the extent feasible to impede any potential- generated glare to comply with the City’s Municipal Code. Impacts to light and glare from the project and cumulative projects would be minimized through compliance with applicable regulations related to light and glare and design requirements. For the rea sons outlined above, cumulative impacts related to aesthetics are determined to be less than significant.
3.1.6 Mitigation Measures
No significant impacts to aesthetics were identified. No mitigation measures are required.
3.1.7 Conclusion
In summary, development of the project would not be built upon any primary or secondary ridgelines nor would the project substantially affect a scenic vista. The project site is not located in close proximity to a designated State Scenic Highway per the Caltrans State Scenic Highway Program . Although the City has designated SR -78 as a view corridor to surrounding ridgelines , the project would not significantly change views from SR -78, and the project would not impede views to any primary or secondary ridgelines from SR-78.
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The project site is located in an urbanized area and would not conflict with applicable zoning and other regulations governing scenic quality , including the scenic resource protection policies in the Conservation and Open Space Element of the City’s General Plan (refer to Section 3.10) .
Implementation of the project would reasonably result in changes to the visual character of the site by allowing industrial development; however, impacts would be minimal to a general lack of public vantage points and a visual conformance with adjacent development . Landscaping associated with the project would also soften views of the project site from adjacent uses.
Concerning l ighting and glare , the project would not include highly reflective finishes or excessive lighting. Further, any exterior night-time lighting associated with the project would be required to comply with the City’s Street Lighting Standards and Specifications and Municipal Code.
It has been determined that implementation of the project would not result in any potential impacts related to aesthetics, and impacts would be less than significant with no mitigation required.
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3.2 AIR QUALITY
This section evaluates the Hughes Circuits Project’s (project) potential impacts on air quality and contribution to regional air quality conditions , identifies associated regulatory requirements, and recommends mitigation measures to reduce impacts to a level below significant , if appropriate. This section is based on the Air Quality and Greenhouse Gas Emissions Technical Report for the Hughes Circuits Project (Air Quality and Greenhouse Gas Emissions Technical Report) prepared by Dudek in January 2023. The complete Air Quality and Greenhouse Gas Emissions Technical Report is included as Appendix B of this environmental impact report (EIR).
Table 3.2-1 summarizes the project - and cumulative-level air quality impacts under each applicable threshold of significance.
Table 3.2-1
Air Quality Summary of Impacts
Threshold of Significance
Project Direct
Impact
Project Cumulative
Impact
Significance
Determination
#1 - Conflict with or obstruct implementation of
the applicable air quality plan.
Less than
Significant
Less than
Significant
Less than
Significant
#2 - Result in a cumulatively considerable net
increase of any criteria pollutant for which the
project region is in non-attainment under an
applicable federal or state ambient air quality
standard.
Less than
Significant
Less than
Significant
Less than
Significant
#3 - Expose sensitive receptors to substantial
pollutant concentrations.
Less than
Significant
Less than
Significant
Less than
Significant
#4 - Result in other emissions (such as those
leading to odors) adversely affecting a substantial
number of people.
Less than
Significant
Less than
Significant
Less than
Significant
3.2.1 Existing Conditions
This section introduces the environmental setting of the project area, including the meteorological/climate conditions for the project area, current physical setting, and pollutant levels in proximity to the project.
Meteorological and Topographic Conditions
The project site is located within the San Diego Air Basin (SDAB) and is subject to the San Diego Air Pollution Control District (SDAPCD) guidelines and regulations. The SDAB is one of 15 air basins that geographically divide the State of California. The primary factors that determine air quality are the locations of air pollutant sources and the amount of pollutants emitted. Meteorological and topographical conditions, however, are also important. Factors such as wind speed and direction, air
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temperature gradients and sunlight, and precipitation and humidity interact with physical landscape features to determine the movement and dispersal of air pollutants. Meteorological and topographical factors that affect air quality in the SDAB are described below.1 Regional Climate and Meteorological Conditions
The climate of the San Diego region, as in most of Southern California, is influenced by the strength and position of the semi-permanent high-pressure system over the Pacific Ocean, known as the Pacific High. This high -pressure ridge over the west coast of ten creates a pattern of late -night and early - morning low clouds, hazy afternoon sunshine, daytime onshore breezes, and little temperature variation year-round. The SDAB is characterized as a Mediterranean climate with dry, warm summers and mild, occasionally wet winters. Average temperature ranges (in degrees Fahrenheit [°F]) from the mid-40s to the high 90s, with an average of 201 days warmer than 70°F. The SDAB experiences 9 to 13 inches of rainfall annually, with most of the region’s precipitation falling from November through March, with infrequent (approximately 10%) pre cipitation during the summer. El Niño and La Niña patterns have large effects on the annual rainfall received in San Diego, where San Diego receives less than normal rainfall during La Niña years.
The interaction of ocean, land, and the Pacific High maintains clear skies for much of the year and influences the direction of prevailing winds (westerly to northwesterly). The winds tend to blow onshore in the day and offshore at night. Local terrain is often the dominant factor inland, and winds in inland mountainous areas tend to blow through the valleys during the day and down the hills and valleys at night.
The favorable climate of San Diego also works to create air pollution problems. Sinking, or subsiding air from the Pacific High, creates a temperature inversion known as a subsidence inversion, which acts as a “lid” to vertical dispersion of pollutants. We ak summertime pressure gradients further limit horizontal dispersion of pollutants in the mixed layer below the subsidence inversion. Poorly dispersed anthropogenic emissions combined with strong sunshine leads to photochemical reactions that result in the creation of ozone (O 3) at this surface layer. In addition, light winds during the summer further limit ventilation.
In the fall months, the SDAB is often impacted by Santa Ana winds, which are the result of a high-pressure system over the Nevada and Utah regions that overcomes the westerly wind pattern and forces hot, dry winds from the east to the Pacific Ocean. The Santa Ana winds are powerful and can
1 The discussion of meteorological and topographical conditions of the SDAB is based on information provided in the San Diego Air Pollution Control District’s 2016 Monitoring Plan (SDAPCD 2017), the County of San Diego Guidelines for Determining Significance – Air Quality (County of San Diego 2007), the County of San Diego General Plan Update EIR (County of San Diego 2011), and the CARB Recommended Area Designation for the 2010 Federal Sulfur Dioxide Standard (CARB 2011).
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blow the SDAB’s pollutants out to sea. However, a weak Santa Ana can transport air pollution from the South Coast Air Basin and greatly increase O3 concentrations in the San Diego area.
Under certain conditions, atmospheric oscillation results in the offshore transport of air from the Los Angeles region to San Diego County. This often produces high O3 concentrations, as measured at air pollutant monitoring stations within San Diego County. The transport of air pollutants from Los Angeles to San Diego can also occur within the stable layer of the elevated subsidence inversion, where high levels of O3 are transported.
Topographical Conditions
Topography in the San Diego region varies greatly, from beaches in the west to mountains and desert in the east; much of the topography in between consists of mesa tops intersected by canyon areas.
Along with local meteorology, topography influences the dispersal and movement of pollutants in the SDAB. Mountains to the east prohibit dispersal of pollutants in that direction and help trap pollutants in inversion layers.
The topography of the SDAB also drives pollutant levels, and the SDAB is classified as a “transport recipient,” whereby pollutants are transported from the South Coast Air Basin to the north and, when the wind shifts direction, from Tijuana, Mexico, to the south.
Regional and Local Air Quality Conditions
San Diego Air Basin Attainment Designation
Pursuant to the 1990 federal Clean Air Act amendments, the U.S. Environmental Protection Agency (EPA) classifies air basins (or portions thereof) as “attainment” or “nonattainment” for each criteria air pollutant, based on whether the National Ambient Air Quality Standards (NAAQS) have been achieved.
Generally, if the recorded concentrations of a pollutant are lower than the standard, the area is classified as “attainment” for that pollutant. If an area exceeds the standard, the area is classified as “nonattainment” for that pollutant. If there is not enough data available to determine whether the standard is exceeded in an area, the area is designated as “unclassified” or “unclassifiable.” The designation of “unclassifiable/attainment” means that the area meets the standard or is expected to be meet the standard despite a lack of monitoring data. Areas that achieve the standards after a nonattainment designation are re -designated as maintenance areas and must have approved Maintenance Plans to ensure continued attainment of the standards. The California Clean Air Act, like its federal counterpart, called for the designation of areas as “attainment” or “nonattainment,” but based on California Ambient Air Quality Standards (CAAQS) rather than the NAAQS. Table 3.2-2 depicts the current attainment status of the project site with respect to the NAAQS and CAAQS, as well as the attainment classifications for the criteria pollutants are outlined in Table 3.2-2.
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Table 3.2-2
San Diego Air Basin Attainment Status
Pollutant
Designation/Classification
National Standards State Standards
Ozone (O3) – 1-hour Attainment (maintenance)a Nonattainment Ozone (O3) – 8-hour Nonattainment (severe) Nonattainment Nitrogen dioxide (NO2) Unclassifiable/attainmentb Attainment Carbon monoxide (CO) Unclassifiable/attainment Attainment Sulfur dioxide (SO2) Unclassifiable/attainment Attainment Respirable particulate matter
(PM10)
Unclassifiable/attainment Nonattainment
Fine particulate matter (PM2.5) Unclassifiable/attainment Nonattainment Lead (Pb) Attainment Attainment
Sulfates (SO4) No national standard Attainment
Hydrogen sulfide (H2S) No national standard Unclassified Vinyl chloride No national standard No designation
Visibility-reducing particles No national standard Unclassified Sources: EPA 2021a (national); CARB 2020 (state).
Definitions: Attainment = meets the standards; attainment/maintenance = achieve the standards after a nonattainment designation; nonattainment = does not meet the standards; unclassified or unclassifiable = insufficient data to classify; unclassifiable/attainment = meets the standard or is expected to be meet the standard despite a lack of monitoring data.
Notes: SDAB = San Diego Air Basin; O 3 = ozone; CO = carbon monoxide; PM 10 = coarse particulate matter; PM 2.5 = fine particulate matter; NO2 = nitrogen dioxide; SO2 = sulfur dioxide. a The national 1 -hour standard of 0.12 parts per million was in effect from 1979 through June 15, 2005. The revoked standard is referenced here because it was employed for such a long period and because this benchmark is addressed in State Implementation Plans.
b The western and central portions of the SDAB are designated attainment, while the eastern portion is designated unclassifiable/ attainment.
In summary, the EPA has designated the SDAB as a nonattainment area for the federal 8 -hour O 3 standard, and the California Air Resources Board (CARB) has designated the SDAB as a nonattainment area for the state 1-hour and 8-hour O3 standards. The SDAB has been designated as a nonattainment area for the state 24 -hour and annual coarse particulate matter (PM10) standards and as a nonattainment area for the state annual fine particulate matter (PM2.5) standard. The SDAB is designated as unclassified or attainment for all other criteria air pollutants.
Local Ambient Air Quality
CARB, air districts, and other agencies monitor ambient air quality at approximately 250 air quality monitoring stations across the state. SDAPCD operates a network of ambient air monitoring stations throughout San Diego County, which measure ambient conce ntrations of pollutants and determine whether the ambient air quality meets the CAAQS and the NAAQS. Air quality monitoring stations usually measure pollutant concentrations 10 feet above ground level; therefore, air quality is often referred to in terms of ground-level concentrations. The SDAPCD monitors air quality conditions at 11 locations throughout the SDAB. Escondido – East Valley Parkway monitoring station cease to collect
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data post-2015; thus, due to proximity to the site and similar geographic and climactic characteristics, the Camp Pendleton, San Diego -Rancho Carmel Drive, San Diego –Kearny Villa Road, and El Cajon - Lexington Elementary School monitoring station concentrations for all pollutants are considered most representative of the project site. Ambient concentrations of pollutants from 2018 through 2020 are presented in Table 3.2-3.
Table 3.2-3
Local Ambient Air Quality Data
Averaging Time Unit
Agency/
Method
Ambient
Air
Quality
Standard
Measured Concentration
by Year Exceedances by Year
2018 2019 2020 2018 2019 2020
Ozone (O3) – Camp Pendleton
Maximum 1-hour
concentration
ppm State 0.12 0.084 0.075 0.094 0 0 0
Maximum 8-hour
concentration
ppm State 0.070 0.069 0.065 0.074 0 0 3
Federal 0.070 0.068 0.064 0.074 0 0 3
Nitrogen Dioxide (NO2) – San Diego – Rancho Carmel Drive Maximum 1-hour
concentration
ppm State 0.18 0.055 0.054 0.054 0 0 0
Federal 0.100 0.055 0.054 0.054 0 0 0
Annual
concentration
ppm State 0.030 0.015 0.014 0.014 — — —
Federal 0.053 0.015 0.014 0.014 — — —
Carbon Monoxide (CO) – San Diego – Rancho Carmel Drive
Maximum 1-hour
concentration
ppm State 20 1.9 4.1 3.3 0 0 0
Federal 35 1.9 4.1 3.3 0 0 0
Maximum 8-hour
concentration
ppm State 9.0 1.4 2.5 1.7 0 0 0
Federal 9 1.4 2.5 1.7 0 0 0
Sulfur Dioxide (SO2) – El Cajon-Lexington Elementary School Maximum 1-hour
concentration
ppm Federal 0.075 0.003
5 0.0008 0.0017 0 0 0
Maximum 24-
hour
concentration
ppm Federal 0.14 0.000
4 0.0003 0.0004 0 0 0
Annual
concentration
ppm Federal 0.030 0.000
1 0.0000
7 0.00009 — — —
Coarse Particulate Matter (PM10)a – San Diego – Kearny Villa Road Maximum 24-
hour
concentration
g/m
3 State 50 38.0 ND ND 0.0 (0) ND (0) ND (0)
Federal 150 38.0 ND ND 0.0 (0) ND (0) ND (0)
Annual
concentration
g/m
3 State 20 18.4 ND ND — — —
Fine Particulate Matter (PM2.5)a – San Diego – Kearny Villa Road Maximum 24-
hour
concentration
g/m
3 Federal 35 32.2 16.2 47.5 0.0 (0) 0.0 (0) 5.8 (2)
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Table 3.2-3
Local Ambient Air Quality Data
Averaging Time Unit
Agency/
Method
Ambient
Air
Quality
Standard
Measured Concentration
by Year Exceedances by Year
2018 2019 2020 2018 2019 2020
Annual
concentration
g/m
3 State 12 8.3 ND ND — — —
Federal 12.0 8.3 7.0 8.7 — — —
Sources: CARB 2022; EPA 2021b.
Notes: ppm = parts per million by volume; ND = insufficient data available to determine the value; — = not available; g/m3 = micrograms per cubic meter.
Data taken from CARB iADAM (http://www.CARB.ca.gov/adam) and EPA AirData (http://www.epa.gov/airdata/) represent the highest concentrations experienced over a given year.
Daily exceedances for particulate matter are estimated days because PM 10 and PM 2.5 are not monitored daily. All other criteria pollutants did not exceed federal or state standards during the years shown. There is no federal standard for 1 -hour ozone, annual PM10, or 24-hour SO2, nor is there a state 24-hour standard for PM2.5.
The Camp Pendleton monitoring station is located at 21441 West B Street, Camp Pendleton, California.
The San Diego-Rancho Carmel Drive monitoring station is located at 11403 Rancho Carmel Drive, San Diego, California.
The El Cajon-Lexington Elementary School monitoring station is located at 533 First Street, El Cajon, California.
The San Diego-Kearny Villa Road monitoring station is located at 6125A Kearny Villa Road, San Diego, California. a Measurements of PM10 and PM2.5 are usually collected every 6 days and every 1 to 3 days, respectively. Number of days exceeding the standards is a mathematical estimate of the number of days concentrations would have been greater than the level of the standard had each day been monitored. The numbers in parentheses are the measured number of samples that exceeded the standard.
Pollutants and Effects
Criteria Air Pollutants
Criteria air pollutants are defined as pollutants for which the federal and state governments have established ambient air quality standards, or criteria, for outdoor concentrations to protect public health. The national and California standards have been set, with an adequate margin of safety, at levels above which concentrations could be harmful to human health and welfare. These standards are designed to protect the most sensitive persons from illness or discomfort. Pollutants of concern include O3, nitrogen dioxide (NO2), carbon monoxide (CO), sulfur dioxide (SO2), particulate matter with an aerodynamic diameter less than or equal to 10 microns (PM10), particulate matter with an aerodynamic diameter less than or equal to 2.5 microns (PM2.5), and lead. In California, sulfates, vinyl chloride, hydrogen sulfide, and visibility-reducing particles are also regulated as criteria air pollutants.
These pollutants, as well as toxic air contaminants (TACs), are discussed in the following paragraphs.2 Ozone. O3 is a strong-smelling, pale blue, reactive, toxic chemical gas consisting of three oxygen atoms.
It is a secondary pollutant formed in the atmosphere by a photochemical process involving the sun’s
2 The descriptions of the criteria air pollutants and associated health effects are based on the U.S.
Environmental Protection Agency’s “Criteria Air Pollutants” (EPA 2018 ), as well as the California Air Resources Board’s “Glossary” (CARB 2019 a) and “Fact Sheet: Air Pollution Sources, Effects and Control” (CARB 2009).
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energy and O 3 precursors. These precursors are mainly oxides of nitrogen (NO x) and volatile organic compounds (VOCs). The maximum effects of precursor emissions on O 3 concentrations usually occur several hours after they are emitted and many miles from the source. Meteorology and terrain play major roles in O3 formation, and ideal conditions occur during summer and early autumn on days with low wind speeds or stagnant air, warm temperatures, and cloudless skies. O 3 exists in the upper atmosphere O 3 layer (stratospheric O 3) and at the Earth’s surface in the troposphere (ground -level O3).3 The O 3 that the EPA and the CARB regulate as a criteria air pollutant is produced close to the ground level, where people live, exercise, and breathe. Ground-level O3 is a harmful air pollutant that causes numerous adverse health effects and is thus considered “bad” O 3. Stratospheric, or “good,” O3 occurs naturally in the upper atmosphere, where it reduces the amount of ultraviolet light (i.e., solar radiation) entering the Earth’s atmosphere. Without the protection of the beneficial stratospheric O 3 layer, plant and animal life would be seriously harmed.
O3 in the troposphere causes numerous adverse health effects; short-term exposures (lasting for a few hours) to O3 at levels typically observed in Southern California can result in breathing pattern changes, reduction of breathing capacity, increased susceptibility to infections, inflammation of the lung tissue, and some immunological changes (EPA 2013).
Inhalation of O3 causes inflammation and irritation of the tissues lining human airways, causing and worsening a variety of symptoms. Exposure to O3 can reduce the volume of air that the lungs breathe in, thereby causing shortness of breath. O3 in sufficient doses increases the permeability of lung cells, rendering them more susceptible to toxins and microorganisms. The occurrence and severity of health effects from O 3 exposure vary widely among individuals, even when the dose and the duration of exposure a re the same. Research shows adults and children who spend more time outdoors participating in vigorous physical activities are at greater risk from the harmful health effects of O 3 exposure. While there are relatively few studies on the effects of O3 on children, the available studies show that children are no more or less likely to suffer harmful effects than adults. However, there are a number of reasons why children may be more susceptible to O 3 and other pollutants. Children and teens spend nearly twice as much time outdoors and engaged in vigorous activities as adults. Children breathe more rapidly than adults and inhale more pollution per pound of their body weight than adults.
Also, children are less likely than adults to notice their own symptoms and avoid harmful exposures.
Further research may be able to better distinguish between health effects in children and adults.
Children, adolescents and adults who exercise or work outdoors, where O 3 concentrations are the highest, are at the greatest risk of harm from this pollutant (CARB 2019b).
Nitrogen Dioxide. NO2 is a brownish, highly reactive gas that is present in all urban atmospheres. The major mechanism for the formation of NO 2 in the atmosphere is the oxidation of the primary air pollutant nitric oxide (NO), which is a colorless, odorless gas. NO x plays a major role, together with
3 The troposphere is the layer of the Earth’s atmosphere nearest to the surface of the Earth. The troposphere extends outward about 5 miles at the poles and about 10 miles at the equator.
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VOCs, in the atmospheric reactions that produce O 3. NOx is formed from fuel combustion under high temperature or pressure. In addition, NO x is an important precursor to acid rain and may affect both terrestrial and aquatic ecosystems. The two major emissions sources are transportation and stationary fuel combustion sources such as electric utility and industrial boilers. NO2 can irritate the lungs, cause bronchitis and pneumonia, and lower resistance to respiratory infections (EPA 2016).
A large body of health science literature indicates that exposure to NO 2 can induce adverse health effects. The strongest health evidence, and the health basis for the ambient air quality standards for NO2, results from controlled human exposure studies that show that NO 2 exposure can intensify responses to allergens in allergic asthmatics. In addition, a number of epidemiological studies have demonstrated associations between NO 2 exposure and premature death, cardiopulmonary effects, decreased lung function growth in children, respiratory symptoms, emergency room visits for asthma, and intensified allergic responses. Infants and children are particularly at risk because they have disproportionately higher exposure to NO2 than adults due to their greater breathing rate for their body weight and their typically greater outdoor exposure duration. Several studies have shown that long - term NO 2 exposure during childhood, the period of rapid lung growth, can lead to smaller lungs at maturity in children with higher levels of exposure compared to children with lower exposure levels. In addition, children with asthma have a greater degree of airway responsiveness compared with adult asthmatics. In adults, the greatest risk is to people who have chronic respiratory dis eases, such as asthma and chronic obstructive pulmonary disease (CARB 2019c).
Carbon Monoxide. CO is a colorless, odorless gas formed by the incomplete combustion of hydrocarbon, or fossil fuels. CO is emitted almost exclusively from motor vehicles, power plants, refineries, industrial boilers, ships, aircraft, and trains. In urban areas, such as t he project location, automobile exhaust accounts for the majority of CO emissions. CO is a nonreactive air pollutant that dissipates relatively quickly; therefore, ambient CO concentrations generally follow the spatial and temporal distributions of vehicular traffic. CO concentrations are influenced by local meteorological conditions—primarily wind speed, topography, and atmospheric stability. CO from motor vehicle exhaust can become locally concentrated when surface-based temperature inversions are combined with calm atmospheric conditions, which is a typical situation at dusk in urban areas from November to February. The highest levels of CO typically occur during the colder months of the year, when inversion conditions are more frequent.
CO is harmful because it binds to hemoglobin in the blood, reducing the ability of blood to carry oxygen.
This interferes with oxygen delivery to the body’s organs. The most common effects of CO exposure are fatigue, headaches, confusion and reduced mental alertness, light-headedness, and dizziness due to inadequate oxygen delivery to the brain. For people with cardiovascular disease, short -term CO exposure can further reduce their body’s already compromised ability to respond to the increased oxygen demands of exercise, exertion, or stress. Inadequate oxygen delivery to the heart muscle leads to chest pain and decreased exercise tolerance. Unborn babies whose mothers experience high levels
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of CO exposure during pregnancy are at risk of adverse developmental effects. Unborn babies, infants, elderly people, and people with anemia or with a history of heart or respiratory disease are most likely to experience health effects with exposure to elevated levels of CO (CARB 2019d).
Sulfur Dioxide. SO2 is a colorless, pungent gas formed primarily from incomplete combustion of sulfur- containing fossil fuels. The main sources of SO2 are coal and oil used in power plants and industries; as such, the highest levels of SO2 are generally found near large industrial complexes. In recent years, SO2 concentrations have been reduced by the increasingly stringent controls placed on stationary source emissions of SO2 and limits on the sulfur content of fuels.
Controlled human exposure and epidemiological studies show that children and adults with asthma are more likely to experience adverse responses with SO2 exposure, compared with the non-asthmatic population. Effects at levels near the 1 -hour standard are those of asthma exacerbation, including bronchoconstriction accompanied by symptoms of respiratory irritation such as wheezing, shortness of breath, and chest tightness, especially during exercise or physical activity. Also, exposure at elevated levels of SO 2 (above 1 parts per million) results in increased incidence of pulmonary symptoms and disease, decreased pulmonary function, and increased risk of mortality. Older people and people with cardiovascular disease or chronic lung disease (such as bronchitis or emphysema) are most likely to experience these adverse effects (CARB 2019e).
SO2 is of concern both because it is a direct respiratory irritant and because it contributes to the formation of sulfate and sulfuric acid in particulate matter (NRC 2005). People with asthma are of particular concern, both because they have increased baseli ne airflow resistance and because their SO2-induced increase in airflow resistance is greater than in healthy people, and it increases with the severity of their asthma (NRC 2005). SO 2 is thought to induce airway constriction via neural reflexes involving irritant receptors in the airways (NRC 2005).
Particulate Matter. Particulate matter pollution consists of very small liquid and solid particles floating in the air, which can include smoke, soot, dust, salts, acids, and metals. Particulate matter can form when gases emitted from industries and motor vehicles undergo ch emical reactions in the atmosphere. PM 2.5 and PM 10 represent fractions of particulate matter. PM 10 consists of particulate matter that is 10 microns or less in diameter, which is about 1/7 the thickness of a human hair. Major sources of PM10 include crushing or grinding operations; dust stirred up by vehicles traveling on roads; wood-burning stoves and fireplaces; dust from construction, landfills, and agriculture; wildfires and brush/waste burning; industrial sources; windblown dust from open lands; and atmospheric chemical and photochemical reactions. PM 2.5 consists of particulate matter that is 2.5 microns or less in diameter, which is roughly 1/28 the diameter of a human hair. PM 2.5 results from fuel combustion (e.g., from motor vehicl es and power generation and industrial facilities), residential fireplaces, and woodstoves. In addition, PM 2.5 can be formed in the atmosphere from gases such as sulfur oxides (SOx), NOx, and VOCs.
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PM2.5 and PM10 pose a greater health risk than larger-size particles. When inhaled, these tiny particles can penetrate the human respiratory system’s natural defenses and damage the respiratory tract.
PM2.5 and PM10 can increase the number and severity of asthma attacks, cause or aggravate bronchitis and other lung diseases, and reduce the body’s ability to fight infections. Very small particles of substances such as lead, sulfates, and nitrates can cause lung damage directly or be absorbed into the bloodstream, causing damage elsewhere in the body. Additionally, these substances can transport adsorbed gases such as chlorides or ammonium into the lungs, also causing injury. Whereas PM 10 tends to collect in the upper portion of the respiratory system, PM 2.5 is so tiny that it can penetrate deeper into the lungs and damage lung tissue. Suspended particulates also damage and discolor surfaces on which they settle and produce haze and reduce regional visibility.
A number of adverse health effects have been associated with exposure to both PM 2.5 and PM10. For PM2.5, short-term exposures (up to 24-hour duration) have been associated with premature mortality, increased hospital admissions for heart or lung causes, acute and chronic bronchitis, asthma attacks, emergency room visits, respiratory symptoms, and restricted activity days. These adverse health effects have been reported primarily in infants, children, and older adults with preexisting heart or lung diseases. In addition, of all of the common air pollutants, PM 2.5 is associated with the greatest proportion of adverse health effects related to air pollution, both in the United States and worldwide based on the World Health Organization’s Global Burden of Disease Project. Short-term exposures to PM10 have been associated primarily with worsening of respiratory diseases, including asthma and chronic obstructive pulmonary disease, leading to hospitalization and emergency department visits (CARB 2017).
Long-term exposure (months to years) to PM 2.5 has been linked to premature death, particularly in people who have chronic heart or lung diseases, and reduced lung function growth in children. The effects of long-term exposure to PM10 are less clear, although several studies suggest a link between long-term PM10 exposure and respiratory mortality. The International Agency for Research on Cancer published a review in 2015 that concluded that particulate matter in outdoor air pollution causes lung cancer (CARB 2017).
Lead. Lead in the atmosphere occurs as particulate matter. Sources of lead include leaded gasoline; the manufacturing of batteries, paints, ink, ceramics, and ammunition; and secondary lead smelters.
Prior to 1978, mobile emissions were the primary source of at mospheric lead. Between 1978 and 1987, the phaseout of leaded gasoline reduced the overall inventory of airborne lead by nearly 95%.
With the phaseout of leaded gasoline, secondary lead smelters, battery recycling, and manufacturing facilities are becoming lead-emissions sources of greater concern.
Prolonged exposure to atmospheric lead poses a serious threat to human health. Health effects associated with exposure to lead include gastrointestinal disturbances, anemia, kidney disease, and in severe cases, neuromuscular and neurological dysfunction. Of particular concern are low-level lead
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exposures during infancy and childhood. Such exposures are associated with decrements in neurobehavioral performance, including intelligence quotient (IQ) performance, psychomotor performance, reaction time, and growth. Children are highly susceptible to the effects of lead.
Sulfates. Sulfates are the fully oxidized form of sulfur, which typically occur in combination with metals or hydrogen ions. Sulfates are produced from reactions of SO 2 in the atmosphere and can result in respiratory impairment, as well as reduced visibility.
Vinyl Chloride. Vinyl chloride is a colorless gas with a mild, sweet odor, which has been detected near landfills, sewage plants, and hazardous waste sites, due to the microbial breakdown of chlorinated solvents. Short-term exposure to high levels of vinyl chloride in air can cause nervous system effects, such as dizziness, drowsiness, and headaches. Long-term exposure through inhalation can cause liver damage, including liver cancer.
Hydrogen Sulfide. Hydrogen sulfide is a colorless and flammable gas that has a characteristic odor of rotten eggs. Sources of hydrogen sulfide include geothermal power plants, petroleum refineries, sewers, and sewage treatment plants. Exposure to hydrogen sulfide can result in nuisance odors, as well as headaches and breathing difficulties at higher concentrations.
Visibility-Reducing Particles. Visibility-reducing particles are any particles in the air that obstruct the range of visibility. Effects of reduced visibility can include obscuring the viewshed of natural scenery, reducing airport safety, and discouraging tourism. Sources of visibility-reducing particles are the same as for PM2.5.
Volatile Organic Compounds. Hydrocarbons are organic gases that are formed from hydrogen and carbon and sometimes other elements. Hydrocarbons that contribute to formation of O 3 are referred to and regulated as VOCs (also referred to as reactive organic gases). Combustion engine exhaust, oil refineries, and fossil -fueled power plants are the sources of hydrocarbons. Other sources of hydrocarbons include evaporation from petroleum fuels, solvents, dry cleaning solutions, and paint.
The primary health effects of VOCs result from the formation of O3 and its related health effects. High levels of VOCs in the atmosphere can interfere with oxygen intake by reducing the amount of available oxygen through displacement. Carcinogenic forms of hydrocarbons, such as benzene, are considered TACs. There are no separate ambient air quality standards for VOCs as a group.
Non-Criteria Air Pollutants
Toxic Air Contaminants. A substance is considered toxic if it has the potential to cause adverse health effects in humans, including increasing the risk of cancer upon exposure, or acute and/or chronic non- cancer health effects. A toxic substance released into the air is considered a TAC. TACs are identified by federal and state agencies based on a review of available scientific evidence. In the state of
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California, TACs are identified through a two -step process that was established in 1983 under the Toxic Air Contaminant Identification and Control Act. This two -step process of risk identification and risk management and reduction was designed to protect r esidents from the health effects of toxic substances in the air. In addition, the California Air Toxics “Hot Spots” Information and Assessment Act, Assembly Bill (AB) 2588, was enacted by the legislature in 1987 to address public concern over the release o f TACs into the atmosphere. The law requires facilities emitting toxic substances to provide local air pollution control districts with information that will allow an assessment of the air toxics problem, identification of air toxics emissions sources, location of resulting hotspots, notification of the public exposed to significant risk, and development of effective strategies to reduce potential risks to the public over 5 years.
Examples include certain aromatic and chlorinated hydrocarbons, certain metals, and asbestos. TACs are generated by a number of sources, including stationary sources, such as dry cleaners, gas stations, combustion sources, and laboratories; mobile sources, such as automobiles; and area sources, such as landfills. Adverse health effects associated with exposure to TACs may include carcinogenic (i.e., cancer-causing) and non -carcinogenic effects. Non -carcinogenic effects typically affect one or more target organ systems and may be experienced on either short-term (acute) or long-term (chronic) exposure to a given TAC.
Diesel Particulate Matter. Diesel particulate matter (DPM) is part of a complex mixture that makes up diesel exhaust. Diesel exhaust is composed of two phases, gas and particle, both of which contribute to health risks. More than 90% of DPM is less than 1 micrometer in diameter (about 1/70 the diameter of a human hair), and thus is a subset of PM 2.5 (CARB 2019f). DPM is typically composed of carbon particles (“soot,” also called black carbon) and numerous organic compounds, including over 40 known cancer-causing organic substances. Examples of these chemicals include polycyclic aromatic hydrocarbons, benzene, formaldehyde, acetaldehyde, acrolein, and 1,3-butadiene (CARB 2019f). The CARB classified “particulate emissions from diesel -fueled engines” (i.e., DPM) (17 CCR 93000) as a TAC in August 1998. DPM is emitted from a broad range of diesel engines: on -road diesel engines, including trucks, buses, and cars, and off-road diesel engines, including locomotives, marine vessels, and heavy-duty construction equipment, among others. Approximately 70% of all airborne cancer risk in California is associated with DPM (CARB 2000). To reduce the cancer risk associated with DPM, CARB adopted a diesel risk reduction plan in 2000 (CARB 2000). Because it is part of PM2.5, DPM also contributes to the same non-cancer health effects as PM2.5 exposure. These effects include premature death; hospitalizations and emergency department visits for exacerbated chronic heart and lung disease, including asthma; increased respiratory symptoms; and decreased lung function in children.
Several studies suggest that exposure to DPM may also facilitate development of new allergies (CARB 2019f). Those most vulnerable to non -cancer health effects are children, whose lungs are still developing, and older people, who often have chronic health problems.
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Valley Fever. Coccidioidomycosis, more commonly known as “Valley Fever,” is an infection caused by inhalation of the spores of the Coccidioides immitis fungus, which grows in the soils of the southwestern United States. When fungal spores are present, any activity that disturbs the soil, such as digging, grading, or other earth-moving operations, can cause the spores to become airborne and thereby increase the risk of exposure. The ecologic factors that appear to be most conducive to survival and replication of the spores are high summer temperatures, mild winters, sparse rainfall, and alkaline sandy soils.
The reported number of cases in California was 7,515 cases in 2018, with the Coccidioidomycosis incidence rate of 18.8 per 100,000 population in 2018 (CDPH 2019). Valley Fever is not considered highly endemic to San Diego. Per the San Diego County Health and Human Services Agency, the 10-year average (2010 –2019) for Coccidioidomycosis cases in San Diego County is 6.3 cases per 100,000 people per year. Similarly, among the total reported incidents of Valley Fever from 2010 through 2019, only 0.9% of the cases reported in San Diego County were in the San Marcos zip code that includes the project site (92078) (County of San Diego 2021).
Even if present at a site, earth-moving activities may not result in increased incidence of Valley Fever.
Propagation of Coccidioides immitis is dependent on climatic conditions, with the potential for growth and surface exposure highest following early seasonal rains and long dry spells. Coccidioides immitis spores can be released when filaments are disturbed by earth -moving activities, although receptors must be exposed to and inhale the spores to be at increased risk of developing Valley Fever. Moreover, exposure to Coccidioides immitis does not guarantee that an individual will become ill—approximately 60% of people exposed to the fungal spores are asymptomatic and show no signs of an infection (USGS 2000).
Odorous Compounds. Odors are generally regarded as an annoyance rather than a health hazard.
Manifestations of a person’s reaction to odors can range from psychological (e.g., irritation, anger, or anxiety) to physiological (e.g., circulatory and respiratory effects, nausea, vomiting, and headache).
The ability to detect odors varies considerably among the population and overall is quite subjective.
People may have different reactions to the same odor. An odor that is offensive to one person may be perfectly acceptable to another (e.g., coffee roaster). An unfamiliar odor is more easily detected and is more likely to cause complaints than a familiar one. In a phenomenon known as odor fatigue, a person can become desensitized to almost any odor, and recognition may only occur with an alteration in the intensity. The occurrence and severity of odor impacts depend on the nature, frequency, and intensity of the source; wind speed and direction; and the sensitivity of receptors.
Sensitive Receptors
Some land uses are considered more sensitive to changes in air quality than others, depending on the population groups and the activities involved. The SDAPCD identifies sensitive receptors as those who are especially susceptible to adverse health effects from exposure to TACs, such as children, the older
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adults, and the ill. Sensitive receptors include schools (grades Kindergarten through 12), day care centers, nursing homes, retirement homes, health clinics, and hospitals within 2 kilometers of the facility (SDAPCD 2019).
The nearest existing sensitive receptors are located to the west of the project site, with multifamily residential (520 feet away) and Bradley Park (550 feet away) the most proximate.
3.2.2 Regulatory Setting
The following section provides a general description of the applicable regulatory requirements pertaining to air quality, including federal, state and local guidelines.
Federal
Federal Clean Air Act
The federal Clean Air Act, passed in 1970 and last amended in 1990, forms the basis for the national air pollution control effort. The EPA is responsible for implementing most aspects of the Clean Air Act, including setting NAAQS for major air pollutants, setting hazardous air pollutant standards, approving state attainment plans, setting motor vehicle emission standards, issuing stationary source emission standards and permits, and establishing acid rain control measures, stratospheric O 3 protection measures, and enforcement provisions. Under the Clean Air Act, NAAQS are established for the criteria pollutants O3, CO, NO2, SO2, PM10, PM2.5, and lead.
The NAAQS describe acceptable air quality conditions designed to protect the health and welfare of the citizens of the nation. The NAAQS (other than for O 3, NO2, SO2, PM10, PM2.5, and those based on annual averages or arithmetic mean) are not to be exceeded more than once per year. NAAQS for O3, NO2, SO2, PM10, and PM 2.5 are based on statistical calculations over 1 - to 3-year periods, depending on the pollutant. The Clean Air Act requires EPA to reassess the NAAQS at least every 5 years to determine whether adopted standards are adequate to protect public health based on current scientific evidence. States with areas that exceed the NAAQS must prepare a state implementation plan that demonstrates how those areas will attain the standards within mandated time frames.
The 1977 federal Clean Air Act amendments required the EPA to identify National Emission Standards for Hazardous Air Pollutants to protect public health and welfare. Hazardous air pollutants include certain volatile organic chemicals, pesticides, herbicides, and radionuclides that present a tangible hazard, based on scientific studies of exposure to humans and other mammals. Under the 1990 federal Clean Air Act Amendments, which expanded the control program for hazardous air pollutants, 187 substances and chemical families were identified as hazardous air pollutants.
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State
The federal Clean Air Act delegates the regulation of air pollution control and the enforcement of the NAAQS to the states. In California, the task of air quality management and regulation has been legislatively granted to CARB, with subsidiary responsibil ities assigned to air quality management districts and air pollution control districts at the regional and county levels. CARB, which became part of the California Environmental Protection Agency in 1991, is responsible for ensuring implementation of the C alifornia Clean Air Act of 1988, responding to the federal Clean Air Act, and regulating emissions from motor vehicles and consumer products.
CARB has established CAAQS, which are generally more restrictive than the NAAQS. The CAAQS describe adverse conditions; that is, pollution levels must be below these standards before a basin can attain the standard. Air quality is considered “in attainment ” if pollutant levels are continuously below the CAAQS and violate the standards no more than once each year. The CAAQS for O3, CO, SO2 (1-hour and 24-hour), NO2, PM10, PM2.5, and visibility-reducing particles are values that are not to be exceeded. All other criteria air pollutants regulated in California (e.g., sulfates, vinyl chloride, hydrogen sulfide, and visibility-reducing particles) are not to be equaled or exceeded. The NAAQS and CAAQS are presented in Table 3.2-4.
Table 3.2-4
Ambient Air Quality Standards
Pollutant Averaging Time
CAAQSa NAAQSb
Concentrationc Primaryc,d Secondaryc,e
O3 1 hour 0.09 ppm (180 g/m3) — Same as primary
standardf 8 hours 0.070 ppm (137 g/m3) 0.070 ppm
(137 g/m3)f
NO2g 1 hour 0.18 ppm (339 g/m3) 0.100 ppm
(188 g/m3)
Same as primary
standard
Annual arithmetic
mean
0.030 ppm (57 g/m3) 0.053 ppm
(100 g/m3)
CO 1 hour 20 ppm (23 mg/m3) 35 ppm (40 mg/m3) None
8 hours 9.0 ppm (10 mg/m3) 9 ppm (10 mg/m3)
SO2h 1 hour 0.25 ppm (655 g/m3) 0.075 ppm
(196 g/m3)
—
3 hours — — 0.5 ppm
(1,300 g/m3)
24 hours 0.04 ppm (105 g/m3) 0.14 ppm
(for certain areas)g
—
Annual — 0.030 ppm
(for certain areas)g
—
PM10i 24 hours 50 g/m3 150 g/m3 Same as primary
standard Annual arithmetic
mean
20 g/m3 —
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Table 3.2-4
Ambient Air Quality Standards
Pollutant Averaging Time
CAAQSa NAAQSb
Concentrationc Primaryc,d Secondaryc,e
PM2.5i 24 hours — 35 g/m3 Same as primary
standard
Annual arithmetic
mean
12 g/m3 12.0 g/m3 15.0 g/m3
Leadj,k 30-day average 1.5 g/m3 — —
Calendar quarter — 1.5 g/m3
(for certain areas)k
Same as primary
standard
Rolling 3-month
average
— 0.15 g/m3
Hydrogen
sulfide
1 hour 0.03 ppm (42 µg/m3) — —
Vinyl
chloridej
24 hours 0.01 ppm (26 µg/m3) — —
Sulfates 24 hours 25 µg/m3 — —
Visibility
reducing
particles
8 hours
(10:00 a.m. to
6:00 p.m. PST)
Insufficient amount to
produce an extinction
coefficient of 0.23 per
kilometer due to
particles when the
relative humidity is less
than 70%
— —
Source: CARB 2016.
Notes: CAAQS = California Ambient Air Quality Standards; NAAQS = National Ambient Air Quality Standards; O 3 = ozone; ppm = parts per million by volume; g/m3 = micrograms per cubic meter; NO 2 = nitrogen dioxide; CO = carbon monoxide; mg/m3= milligrams per cubic meter; SO2 = sulfur dioxide; PM10 = coarse particulate matter; PM2.5 = fine particulate matter. a California standards for O3, CO, SO2 (1-hour and 24-hour), NO2, suspended particulate matter—PM10, PM2.5, and visibility- reducing particles, are values that are not to be exceeded. All others are not to be equaled or exceeded. CAAQS are listed in the Table of Standards in Section 70200 of Title 17 of the California Code of Regulations. b National standards (other than O 3, NO 2, SO 2, particulate matter, and those based on annual averages or annual arithmetic mean) are not to be exceeded more than once a year. The O 3 standard is attained when the fourth -highest 8-hour concentration measured at each site in a year, averaged over 3 years, is equal to or less than the standard. For PM10, the 24-hour standard is attained when the expected number of days per calendar year with a 24 -hour average concentration above 150 µg/m3 is equal to or less than 1. For PM2.5, the 24-hour standard is attained when 98% of the daily concentrations, averaged over 3 years, are equal to or less than the standard. c Concentration expressed first in units in which it was promulgated. Equivalent units given in parentheses are based upon a reference temperature of 25°C and a reference pressure of 760 torr. Most measurements of air quality are to be corrected to a reference temperature of 25°C and a reference pressure of 760 torr; ppm in this table refers to ppm by volume, or micromoles of pollutant per mole of gas.
d National primary standards: the levels of air quality necessary, with an adequate margin of safety to protect the public health. e National secondary standards: the levels of air quality necessary to protect the public welfare from any known or anticipated adverse effects of a pollutant.
f On October 1, 2015, the primary and secondary NAAQS for O3 were lowered from 0.075 ppm to 0.070 ppm. g To attain the 1-hour national standard, the 3 -year average of the annual 98th percentile of the 1 -hour daily maximum concentrations at each site must not exceed 100 parts per billion (ppb). Note that the national 1 -hour standard is in units of ppb. California standards are in units of ppm. To directly compare the national 1-hour standard to the California standards the units can be converted from ppb to ppm. In this case, the national standard of 100 ppb is identical to
0.100 ppm.
h On June 2, 2010, a new 1 -hour SO2 standard was established and the existing 24 -hour and annual primary standards were revoked. To attain the 1 -hour national standard, the 3 -year average of the annual 99th percentile of the 1 -hour
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daily maximum concentrations at each site must not exceed 75 ppb. The 1971 SO 2 national standards (24 -hour and annual) remain in effect until 1 year after an area is designated for the 2010 standard, except that in areas designated nonattainment of the 1971 standards, the 1971 standards remain in effect until implementation plans to attain or maintain the 2010 standards are approved.
i On December 14, 2012, the national annual PM 2.5 primary standard was lowered from 15 g/m3 to 12.0 g/m3. The existing national 24 -hour PM 2.5 standards (primary and secondary) were retained at 35 g/m3, as was the annual secondary standard of 15 μg/m3. The existing 24-hour PM10 standards (primary and secondary) of 150 g/m3 also were retained. The form of the annual primary and secondary standards is the annual mean, averaged over 3 years. j CARB has identified lead and vinyl chloride as TACs with no threshold level of exposure for adverse health effects determined. These actions allow for the implementation of control measures at levels below the ambient concentrations specified for these pollutants.
k The national standard for lead was revised on October 15, 2008, to a rolling 3-month average. The 1978 lead standard (1.5 μg/m 3 as a quarterly average) remains in effect until 1 year after an area is designated for the 2008 standard, except that in areas designated nonattainment for the 1978 standard, the 1978 standard remains in effect until implementation plans to attain or maintain the 2008 standard are approved.
California Clean Air Act
The California Clean Air Act, signed into law in 1988, requires all areas of the state to achieve and maintain the CAAQS by the earliest practical date. Air pollution from commercial and industrial facilities is regulated by local air quality management di stricts, whereas mobile sources of air pollution are regulated by CARB and the EPA. All air pollution control districts have been formally designated as “attainment” or “nonattainment” for each state air quality standard, as shown in Table
3.2-2. Areas in California where ambient air concentrations of pollutants are higher than the state standard are considered to be in “non -attainment” status for that pollutant. Non -attainment designations are categorized into three levels of severity: (1) moderate, (2) se rious, and (3) severe.
If there are inadequate or inconclusive data to make a definitive attainment designation, districts are considered “unclassified.”
Toxic Air Contaminants
The state Air Toxics Program was established in 1983 under AB 1807 (Tanner). The California TAC list identifies more than 700 pollutants, of which carcinogenic and noncarcinogenic toxicity criteria have been established for a subset of these pollutants pur suant to the California Health and Safety Code.
In accordance with AB 2728, the state list includes the (federal) hazardous air pollutants. In 1987, the Legislature enacted the Air Toxics “Hot Spots” Information and Assessment Act of 1987 (AB 2588) to address public concern over the release of TACs into the atmosphere. AB 2588 requires facilities emitting toxic substances to provide local air pollution control districts with information that will allow an assessment of the air toxics problem, identification of air toxics emissions sources, location of resulting hotspots, notification of the public exposed to significant risk, and development of effective strategies to reduce potential risks to the public over 5 years. TAC emissions from individual facilities are quantified and prioritized. “High -priority” facilities are required to perform a health risk assessment, and if specific thresholds are exceeded, the facility operator is required to communicate the results to the public in the form of notices and public meetings.
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In 2000, CARB approved a comprehensive Diesel Risk Reduction Plan to reduce diesel emissions from new and existing diesel -fueled vehicles and engines (CARB 2000). The regulation is anticipated to result in an 80% decrease in statewide diesel health risk by 2020 compared with the diesel risk in 2000. Additional regulations apply to new trucks and diesel fuel, including the On -Road Heavy Duty Diesel Vehicle (In -Use) Regulation, the On -Road Heavy Duty (New) Vehicle Program, the In -Use Off- Road Diesel Vehicle R egulation, and the New Off -Road Compression -Ignition (Diesel) Engines and Equipment Program. These regulations and programs have timetables by which manufacturers must comply and existing operators must upgrade their diesel -powered equipment. There are sev eral airborne toxic control measures that reduce diesel emissions, including In-Use Off-Road Diesel-Fueled Fleets (13 CCR 2449 et seq.) and In-Use On-Road Diesel-Fueled Vehicles (13 CCR 2025).
Idling of Commercial Heavy Duty Trucks (13 CCR 2485)
In July 2004, CARB adopted an Airborne Toxic Control Measure (ATCM) to control emissions from idling trucks. The ATCM prohibits idling for more than 5 minutes for all commercial trucks with a gross vehicle weight rating over 10,000 pounds. The ATCM contains an exception that allows trucks to idle while queuing or involved in operational activities.
In-Use Off-Road Diesel-Fueled Fleets (13 CCR 2449 et seq.) In July 2007, CARB adopted an ATCM for in-use off-road diesel vehicles. This regulation requires that specific fleet average requirements are met for NOx emissions and for particulate matter emissions.
Where average requirements cannot be met, best available control technology requirements apply.
The regulation also includes several recordkeeping and reporting requirements.
In response to AB 8 2X, the regulations were revised in July 2009 (effective December 3, 2009) to allow a partial postponement of the compliance schedule in 2011 and 2012 for existing fleets. On December 17, 2010, CARB adopted additional revisions to further delay the deadlin es reflecting reductions in diesel emissions due to the poor economy and overestimates of diesel emissions in California. The revisions delayed the first compliance date until no earlier than January 1, 2014, for large fleets, with final compliance by January 1, 2023. The compliance dates for medium fleets were delayed until an initial date of January 1, 2017, and final compliance date of January 1, 2023. The compliance dates for small fleets were delayed until an initial date of January 1, 2019, and final compliance date of January 1, 2028. Correspondingly, the fleet average targets were made more stringent in future compliance years. The revisions also accelerated the phaseout of older equipment with newer equipment added to existing large and medium fleet s over time, requiring the addition of Tier 2 or higher engines starting on March 1, 2011, with some exceptions: Tier 2 or higher engines on January 1, 2013, without exception; and Tier 3 or higher engines on January 1, 2018 (January 1, 2023, for small fleets).
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On October 28, 2011 (effective December 14, 2011), the Executive Officer approved amendments to the regulation. The amendments included revisions to the applicability section and additions and revisions to the definition. The initial date for requiring the addition of Tier 2 or higher engines for large and medium fleets, with some exceptions, was revised to January 1, 2012. New provisions also allow for the removal of emission control devices for safety or visibility purposes. The regulation also was amended to combine the particulate matter and NOx fleet average targets under one, instead of two, sections. The amended fleet average targets are based on the fleet’s NO x fleet average, and the previous section regarding particulate matter performance requirements was deleted completely. The best available control technology requirements, if a fleet cannot comply with the fleet average requirements, were restructured and c larified. Other amendments to the regulations included minor administrative changes to the regulatory text.
In-Use On-Road Diesel-Fueled Vehicles (13 CCR 2025)
On December 12, 2008, CARB adopted an ATCM to reduce NOx and particulate matter emissions from most in -use on -road diesel trucks and buses with a gross vehicle weight rating greater than 14,000 pounds. The original ATCM regulation required fleets of on -road trucks to limit their NO x and particulate matter emissions through a combination of exhaust retrofit equipment and new vehicles.
The regulation limited particulate matter emissions for most fleets by 2011, and limited NOx emissions for most fleets by 201 3. The regulation did not require any vehicle to be replaced before 2012 and never required all vehicles in a fleet be replaced.
In December 2009, the CARB Governing Board directed staff to evaluate amendments that would provide additional flexibility for fleets adversely affected by the struggling California economy. On December 17, 2010, CARB revised this ATCM to delay its implementation along with limited relaxation of its requirements. Starting on January 1, 2015, lighter trucks with a gross vehicle weight rating of 14,001 to 26,000 pounds with 20 -year-old or older engines need to be replaced with newer trucks (2010 model year em issions equivalent as defined in the regulation). Trucks with a gross vehicle weight rating greater than 26,000 pounds with 1995 model year or older engines needed to be replaced as of January 1, 2015. Trucks with 1996 to 2006 model year engines must install a Level 3 (85% control) diesel particulate filter starting on January 1, 2012, to January 1, 2014, depending on the model year, and then must be replaced after 8 years. Trucks with 2007 to 2009 model year engines have no requirements until 2023, at which time they must be replaced with 2010 model year emissions-equivalent engines, as defined in the regulation. Trucks with 2010 model year engines would meet the final compliance requirements. The ATCM provides a phase -in option under which a fleet operator would equip a percentage of trucks in the fleet with diesel particulate filters, starting at 30% as of January 1, 2012, with 100% by January 1, 2016. Under each option, delayed compliance is granted to fleet operators who have or will comply with requirements before the required deadlines.
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On September 19, 2011 (effective December 14, 2011), the Executive Officer approved amendments to the regulations, including revisions to the compliance schedule for vehicles with a gross vehicle weight rating of 26,000 pounds or less to clarify that all vehicles must be equipped with 2010 model year emissions equivalent engines by 2023. The amendments included revised and additional credits for fleets that have downsized; implement early particulate matter retrofits; incorporate hybrid vehicles, alternat ive-fueled vehicles, and vehicles with heavy -duty pilot ignition engines; and implement early addition of newer vehicles. The amendments included provisions for additional flexibility, such as for low-usage construction trucks, and revisions to previous exemptions, delays, and extensions. Other amendments to the regulations included minor administrative changes to the regulatory text, such as recordkeeping and reporting requirements related to other revisions.
California Health and Safety Code Section 41700
Section 41700 of the Health and Safety Code states that a person must not discharge from any source whatsoever quantities of air contaminants or other material that cause injury, detriment, nuisance, or annoyance to any considerable number of persons or to the public; or that endanger the comfort, repose, health, or safety of any of those persons or the public; or that cause, or have a natural tendency to cause, injury or damage to business or property. This section also applies to sources of objectionable odors.
Local
San Diego Air Pollution Control District
SDAPCD has prepared the 2020 Plan for Attaining the National Ambient Air Quality Standards for Ozone in San Diego County (2020 Attainment Plan) that demonstrates how the region will further reduce air pollutant emissions in order to attain the current NAAQS for O3. The 2020 Attainment Plan was approved by the SDAPCD on October 14, 2020. On November 19, 2020, CARB adopted the 2020 Attainment Plan for attaining the federal 8 -hour 75 parts per billion and 70 parts per billion O3 standards and projects attainment for the standards by 2026 and 2032, respectively (SDAPCD 2020).
The 2020 Attainment Plan was submitted to the EPA as a revision to the California State Implementation Plan (SIP) for attaining the O3 NAAQS.
As described in the 2020 Attainment Plan, although San Diego County has experienced substantial growth in gross regional product, population, vehicle miles traveled, and energy consumption between 2000–2018, the O3 emission levels declined, and air quality continued to improve. Total regionwide NOx and VOC emissions were reduced by over 60% and 50%, respectively, from 2000 to 2018. These improvements were the result of a combination of regulatory and incentive-based approaches at local, State, and federal gove rnment levels. Ongoing implementation of these strategies will continue reducing total O 3 precursor emissions as new lower emitting sources replace older, higher -emitting sources at the end of their useful lives (SDAPCD 2020).
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SDAPCD and the San Diego Association of Governments (SANDAG) are responsible for developing and implementing the clean air plan for attainment and maintenance of the ambient air quality standards in the SDAB. The Regional Air Quality Strategy (RAQS) for the SDAB was initially adopted in 1991 and is updated every 3 years, most recently in 2016 (SDAPCD 2016). The RAQS outlines SDAPCD’s plans and control measures designed to attain the CAAQS for O3. The RAQS relies on information from CARB and SANDAG, including mobile and area source emissions, as well as information regarding projected growth in San Diego County and the cities in San Diego County, to forecast future emissions and then determine from that the strategies necessary for the reduction of emissions through regulatory controls. The CARB mobile source emission projections and SANDAG growth projections are based on population, vehicle trends, and land use plans developed by the County of San Diego (County) and the cities in the County as part of the development of their general plans.
In December 2016, SDAPCD adopted the revised RAQS for the County. Since 2007, the San Diego region has reduced daily VOC emissions and NOx emissions by 3.9% and 7.0%, respectively; SDAPCD expects to continue reductions through 2035 (SDAPCD 2016). These reductions were achieved through implementation of six VOC control measures and three NO x control measures adopted in SDAPCD’s 2009 RAQS (SDAPCD 2009a); in addition, SDAPCD is considering additional measures, including three VOC measures and four control meas ures to reduce 0.3 daily tons of VOCs and 1.2 daily tons of NO x, provided they are found to be feasible region -wide. In addition, SDAPCD has implemented nine incentive -based programs, has worked with SANDAG to implement regional transportation control measures, and has reaffirmed the state emission offset repeal. Notably, the SDAPCD has prepared the Draft 2022 Regional Air Quality Strategy (2022 RAQS), which contains proposed and scheduled measures that would provide additional direct emission reductions of O3 precursors, as well as indirect reductions of particulate matter and greenhouse gas emissions. The SDAPCD has adopted and/or amended seven existing measures since 2016, proposed and scheduled eight measures in the next 3 years, and proposed 14 additional measures for further study in the next 3 years. All proposed measures will further reduce air pollution beyond levels established in the 2016 RAQS. Together, the proposed control measures scheduled for consideration are estimated to reduce VOC emissions by approximately 0.04 tons per day and NO x emissions by 0.59 tons per day (SDAPCD 2022).
In regard to particulate matter emissions reduction efforts, in December 2005, SDAPCD prepared a report titled “Measures to Reduce Particulate Matter in San Diego County” to address implementation of Senate Bill 656 in San Diego County (Senate Bill 656 required additional controls to reduce ambient concentrations of PM 10 and PM 2.5) (SDAPCD 2005). In the report, SDAPCD evaluated the implementation of source -control measures that would reduce particulate matter emissions associated with residential wood combu stion; various construction activities including earthmoving, demolition, and grading; bulk material storage and handling; carryout and trackout removal and cleanup methods; inactive disturbed land; disturbed open areas; unpaved parking lots/staging areas; unpaved roads; and windblown dust (SDAPCD 2005).
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In addition to SDAPCD’s regional planning efforts, t he following SDAPCD rules and regulations also would apply to the project:
• SDAPCD Regulation IV: Prohibitions; Rule 50: Visible Emissions. Prohibits any activity causing air contaminant emissions darker than 20% opacity for more than an aggregate of 3 minutes in any consecutive 60-minute time period. In addition, Rule 50 prohibits any diesel pile-driving hammer activity causing air contaminant emissions for a period or periods aggregating more than 4 minutes during the driving of a single pile (SDAPCD 1997). • SDAPCD Regulation IV: Prohibitions; Rule 51: Nuisance. Prohibits the discharge, from any source, of such quantities of air contaminants or other materials that cause or have a tendency to cause injury, detriment, nuisance, annoyance to people and/or the public, or damage to any business or property (SDAPCD 1976).
• SDAPCD Regulation IV: Prohibitions; Rule 55: Fugitive Dust. Regulates fugitive dust emissions from any commercial construction or demolition activity capable of generating fugitive dust emissions, including active operations, open storage piles, and inactive disturbed areas, as well as track-out and carry-out onto paved roads beyond a project site (SDAPCD 2009b). • SDAPCD Regulation IV: Prohibitions; Rule 67.0.1: Architectural Coatings. Requires manufacturers, distributors, and end users of architectural and industrial maintenance coatings to reduce VOC emissions from the use of these coatings, primarily by placing limits on the VOC content of various coating categories (SDAPCD 2015a). • SDAPCD Regulation IV: Prohibitions; Rule 67.7: Cutback and Emulsified Asphalts. This rule prohibits manufacturers, distributors, and end users of cutback and emulsified asphalt materials for the paving, construction or maintenance of parking lots, driveways, streets and highways from applying asphalt material or road oils that contain more than 0.5% by volume VOCs that evaporate at 260ºC (500ºF) or less (SDAPCD 1979).
San Diego Association of Governments
SANDAG is the regional planning agency for the County and serves as a forum for regional issues relating to transportation, the economy, community development, and the environment. SANDAG serves as the federally designated metropolitan planning organization for the County. With respect to air quality planning and other regional issues, SANDAG has prepared San Diego Forward: The Regional Plan (Regional Plan) for the San Diego region (SANDAG 2015). The Regional Plan combines the big - picture vision for how the region will grow over the next 35 years with an implementation program to help make that vision a reality. The Regional Plan, including its Sustainable Communities Strategy, is built on an integrated set of public policies, strategies, and investments to maintain, manage, and improve the transportation system so that it meets the diverse needs of the San Diego region through 2050. The Regional Plan was updated in 2021, which was the result of years of planning, data analysis, and community engagement to re imagine the San Diego region with a transformative transportation system, a sustainable pattern of growth and development, and innovative demand and management strategies (SANDAG 2021). The 2021 Regional Plan includes a Sustainable
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Communities Strategy , which describes coordinated transportation and land use planning that exceeds the state’s target for reducing per-capita greenhouse gas emissions set by CARB. The state- mandated target is a 19% reduction —compared with 2005—in per-capita greenhouse gas emissions from cars and light-duty trucks by 2035. The 2021 Regional Plan achieves a 20% reduction by then.
The 2021 Regional Plan also puts forth a forecasted development pattern that is driven by regional goals for sustainability, mobility, housing affordability, and economic prosperity.
City of San Marcos General Plan
The City of San Marcos (City) General Plan (City of San Marcos 2012) includes various policies related to reducing air pollutant emissions. Applicable policies include the following:
Land Use and Community Design Element
• Goal LU -2: Promote development standards and land use patterns that encourage long -term environmental sustainability.
• Policy LU -2.1: Promote compact development patterns that reduce air pollution and automobile dependence and facilitate walking, bicycling, and transit use. • Goal LU-3: Develop land use patterns that are compatible with and support a variety of mobility opportunities and choices.
• Policy LU-3.1: Require that new development and redevelopment incorporate connections and reduce barriers between neighborhoods, transit corridors, and activity centers within the City.
Mobility Element
o Policy M-2.1: Work with new development to design roadways that minimize traffic volumes and/or speed, as appropriate within residential neighborhoods; while maintaining the City’s desire to provide connectivity on the roadway network. • Goal M -3 Promote and encourage use of alternative transportation modes, including transit, bicycles, neighborhood electric vehicles (NEVs), and walking, within the City.
Conservation and Open Space Element
o Policy COS-4.6: Promote efficient use of energy and conservation of available resources in the design, construction, maintenance and operation of public and private facilities, infrastructure and equipment.
o Policy COS-4.8: Encourage and support the generation, transmission and use of renewable energy.
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The project’s consistency with applicable General Plan goals and policies is discussed in Section 3.10, Land Use and Planning, and throughout Chapter 3, Environmental Analysis, of this EIR.
3.2.3 Thresholds of Significance
The significance criteria used to evaluate the project impacts to air quality are based on Appendix G of the California Environmental Quality Act ( CEQA) Guidelines. According to Appendix G of the CEQA Guidelines, a significant impact related to air quality would occur if the project would:
• Threshold #1: Conflict with or obstruct implementation of the applicable air quality plan. • Threshold #2: Result in a cumulatively considerable new increase of any criteria pollutant for which the project region is non -attainment under an applicable federal or state ambient air quality standard.
• Threshold #3: Expose sensitive receptors to substantial pollutant concentrations. • Threshold #4: Result in other emissions (such as those leading to odors) adversely affecting a substantial number of people.
Appendix G of the CEQA Guidelines (14 CCR 15000 et seq.) indicates that, where available, the significance criteria established by the applicable air quality management district or air pollution control district may be relied upon to determine whether the project would have a significant impact on air quality.
County of San Diego and SDAPCD
Neither the City nor the SDAPCD have developed CEQA thresholds of significance for air quality; however, the County has established CEQA screening-level thresholds for air quality impact analyses based on the SDAPCD Air Quality Impact Assessments trigger l evels, which are based on emissions levels identified under the New Source Review program. As part of its air quality permitting process, SDAPCD has established thresholds in Rule 20.2 and Rule 20.3 requiring the preparation of Air Quality Impact Assessmen ts for permitted stationary sources (non -major and major stationary sources, respectively) (SDAPCD 2020, 2021). SDAPCD sets forth quantitative emission thresholds below which a stationary source would not have a significant impact on ambient air quality. Because SDAPCD Rules
20.2 and 20.3 do not identify a VOC threshold, the County of San Diego established a VOC threshold based on the South Coast Air Quality Management District’s VOC threshold.
For CEQA purposes, the screening-level thresholds established by the County of San Diego can be used as numeric methods to demonstrate that a project’s total emissions would not result in a significant impact to air quality for projects within San Diego Co unty. Accordingly, the thresholds listed in Table
3.2-5 are used to evaluate whether project-related emissions could cause a significant impact on air quality. For nonattainment pollutants, if emissions exceed the thresholds shown in Table 3.2-5, the
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project could have the potential to result in a cumulatively considerable net increase in these pollutants and thus, could have a significant impact on the ambient air quality; conversely, emissions below the screening-level thresholds would not cause a sig nificant impact. A project that involves a use that would produce objectionable odors would be deemed to have a significant odor impact if it would affect a considerable number of off-site receptors.
Table 3.2-5
Air Quality Significance Thresholds
Construction and Operational Emissions
Pollutant
Total Emissions
Pounds per
Hour
Pounds per
Day Tons per Year
Respirable particulate matter (PM10) — 100 15
Fine particulate matter (PM2.5) — 55 10
Oxides of nitrogen (NOx) 25 250 40
Sulfur oxides (SOx) 25 250 40
Carbon monoxide (CO) 100 550 100
Lead and lead compounds — 3.2 0.6
Volatile organic compounds (VOC) — 75a 13.7
Source: SDAPCD Rules 20.2(d)(2) and 20.3(d)(2).
a VOC threshold based on South Coast Air Quality Management District (SCAQMD) levels for Coachella Valley, which have similar federal and state attainment status to San Diego.
Approach and Methodology
Construction Emissions
Emissions from the construction phase of the project were estimated using California Emissions Estimator Model ( CalEEMod) Version 2020.4.0 (CAPCOA 2021). For purposes of estimating project emissions, and based on information provided by the project applicant, it is assumed that construction of the project would commence in September 20234 and would last approximately 12 months, ending in August 2024. Please see Appendix B for detailed c onstruction scenario assumptions, including phasing, equipment mix, and vehicle trips, which were based on information provided by the project applicant and CalEEMod default values when project specifics were not known.
Construction of project components would be subject to SDAPCD Rule 55 – Fugitive Dust Control. This rule requires that construction of project components include steps to restrict visible emissions of fugitive dust beyond the property line (SDAPCD 2009b). Compliance with Rule 55 would limit fugitive
4 The analysis assumes a construction start date of September 2023 , which represents the earliest date construction would initiate. Assuming the earliest start date for construction represents the worst -case scenario for criteria air pollutant and greenhouse gas emissions because equipment and vehicle emission factors for later years would be slightly less due to more stringent standards for in -use off-road equipment and heavy-duty trucks, as well as fleet turnover replacing older equipment and vehicles in later years.
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dust (PM 10 and PM 2.5) that may be generated during grading and construction activities. To reflect implementation of proposed dust control strategies, it was assumed that the exposed areas would be watered two times per day (55% reduction in PM 10 and PM2.5). In addition, the project applicant has committed that all diesel-powered off-road equipment over 50 horsepower will meet the U.S. EPA Tier 4 Final emission standards for off-road equipment, which is included in the analysis as Project Design Feature (PDF) AQ-1. Finally, as specified in PDF-AQ-2, only low-VOC architectural coatings (i.e., no more than 50 grams per liter VOC) will be used for the interiors and exteriors of the buildings.
Operational Emissions
Emissions from the operational phase of the project were estimated using CalEEMod Version 2020.4.0 for mobile sources (vehicular traffic); energy sources from natural gas usage; area sources (including the use of landscaping equipment, consumer products, and from architectural coatings); and off-road equipment (one CNG forklift). Please see Appendix B for detailed operational scenario assumptions for these sources.
Operational year 2025 was assumed as the first full year after completion of project construction.
Project Design Features
PDFs that are relevant to the air quality analysis are presented below. This impact analysis assumes that all PDFs would be implemented as conditions of approval, as defined below.
PDF-AQ-1. The project applicant will employ off-road equipment that meets the U.S. EPA’s Tier 4 Final emission standards for nonroad engines over 50 horsepower.
PDF-AQ-2. The project applicant will use low-VOC architectural coatings (i.e., no more than 50 grams per liter VOC content) for building interiors and exteriors.
3.2.4 Project Impact Analysis
Threshold #1: Would the project conflict with or obstruct implementation of the applicable air quality plan?
As mentioned in Section 3.2.2 , Regulatory Setting, above, the SDAPCD is responsible for developing and implementing the clean air plans for attainment and maintenance of the ambient air quality standards in the basin —specifically, the SIP and RAQS. 5 SANDAG is responsible for developing forecasts and data that are used by SDAPCD in preparing the SIP and RAQS. The federal O 3 maintenance plan, which is part of the SIP, was adopted in 2012. The SIP includes a demonstration that current strategies and tactics will maintain acceptable air quality in the basin based on the NAAQS.
The RAQS outlines SDAPCD’s plans and control measures designed to attain the state air quality
5 For the purpose of this discussion, the relevant federal air quality plan is the Ozone Maintenance Plan (SDAPCD 2012). The RAQS is the applicable plan for purposes of State air quality planning. Both plans reflect growth projections in the basin.
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standards for O3. The SIP and RAQS rely on information from CARB and SANDAG, including mobile and area source emissions as well as information regarding projected growth in the County as a whole and the cities in the County, to project future emissions and determine the s trategies necessary for the reduction of emissions through regulatory controls. CARB mobile source emission projections and SANDAG growth projections are based on population, vehicle trends, and land use plans developed by the County and the cities in the County as part of the development of their general plans.
While the SDAPCD and City do not provide guidance regarding the analysis of impacts associated with air quality plan conformance, the County’s Guidelines for Determining Significance and Report and Format and Content Requirements – Air Quality does discuss conformance with the RAQS (County of San Diego 2007). The guidance indicates that, if the project, in conjunction with other projects, contributes to growth projections that would not exceed SANDAG’s growth projections for the City, the project would not be in conflict with the RAQS (County of San Diego 2007). If a project includes development that is greater than that anticipated in the local plan and SANDAG’s growth projections, the project might be in conflict with the SIP and RAQS and may contribute to a potentially significant cumulative impact on air quality.
The project site is designated as Light Industrial (LI) in the City’s General Plan and is zoned Light Industrial (L-I). The project would be consistent with these designations. As described in Section 3.12, Population and Housing, the City of San Marcos is forecasted to grow from 94,258 persons and 41,096 employees in 2016 to 119,098 persons and 63,031 employees in 2050, which is a population and employment increase of 24,840 and 21,935, respectively (SANDAG 2021). As such, the project- related increase of approximately 60 employees would represent a nominal percentage of the City’s projected future population and employees. Additionally, the project would not induce population growth to the area. Per CEQA Guideline Section 15206(b), the project would not be considered regionally significant because it would not have the potential to substantially affect housing, employment, or population projections within the San Diego region, which are the basis of the RAQS projections. As such, the project would not conflict with or o bstruct implementation of the RAQS.
Furthermore, the project would not result in substantial construction or operational emissions that would conflict with the local air quality plan.
Therefore, implementation of the project would not conflict with the RAQS or SIP and proposed development would be consistent with the growth in the region. Impacts would be less than significant.
Threshold #2: Would the project result in a cumulatively considerable ne t increase of any criteria pollutant for which the project region is non-attainment under an applicable federal or state ambient air quality standard?
Past, present, and future development projects may contribute to the SDAB adverse air quality impacts on a cumulative basis. By its nature, air pollution is largely a cumulative impact. The nonattainment status of regional pollutants is a result of past an d present development, and SDAPCD develops and
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implements plans for future attainment of ambient air quality standards. Based on these considerations, project -level thresholds of significance for criteria pollutants are used in the determination of whether a project’s individual emissions would have a cumulatively considerable contribution on air quality. If a project’s emissions would exceed the applied significance thresholds, it would have a cumulatively considerable contribution. Conversely, projects that do not exceed the project-specific thresholds are generally not considered to be cumulatively significant.
Construction and operation of the project would result in emissions of criteria air pollutants, which may result in a cumulatively considerable net increase in emissions of criteria air pollutants for which the SDAB is designated as nonattainment under the NAAQS or CAAQS. As discussed previously, the SDAB has been designated as a federal nonattainment area for O 3 and a state nonattainment area for O 3, PM10, and PM 2.5. The following discussion quantitatively evaluates potential short -term construction and long-term operational impacts that would result from implementation of the project.
Construction Emissions
Proposed construction activities would result in the temporary addition of pollutants to the local airshed caused by on-site sources (i.e., off-road construction equipment, soil disturbance, and VOC off- gassing from architectural coatings and asphalt pavem ent application) and off -site sources (i.e., on - road haul trucks, delivery trucks, and worker vehicle trips). Construction emissions can vary substantially from day to day, depending on the level of activity, the specific type of operation, and for dust, the prevailing weather conditions. Therefore, such emissions levels can only be estimated, with a corresponding uncertainty in precise ambient air quality impacts.
As discussed under Section 3.2.3 , Thresholds of Significance, criteria air pollutant emissions associated with construction activity were quantified using CalEEMod (CAPCOA 2021). Construction emissions were calculated for the estimated worst -case day over the construction period associated with each phase and reported as the maximum daily emissions estimated during each year of construction (2023–2024). Construction schedule assumptions, including phase type, duration, and sequencing, were based on information provided by the applicant or CalEEMod defaults and are intended to represent a reasonable scenario based on the best information available. NO x and CO emissions would primarily result from the use of construction equipment and motor vehicles. Notably, as outlined in PDF-AQ-1, the project applicant will employ off-road equipment that meets the U.S. EPA’s Tier 4 Final emission standards for nonroad engines over 50 horsepower.
Fugitive dust (PM 10 and PM 2.5) emissions would primarily result from grading and site preparation activities. The project would be required to comply with SDAPCD Rule 55, Fugitive Dust Control , and Rule 50, Visible Emissions. These rules require that the project take steps to restrict visible emissions and fugitive dust beyond the property line. Compliance with Rule 55 would limit fugitive dust (PM 10 and PM2.5) generated during grading and construction activities. To account for dust control measures
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in the calculations, it was assumed that the project would ensure that active sites be watered at least two times daily. The application of architectural coatings, such as exterior application/interior paint and other finishes would produce VOC emissions; however, per PDF -AQ-2, only low-VOC coatings will be used for the building interiors and exteriors. The contractor would also be required to comply with the requirements of SDAPCD’s Rule 67.7, Cutback and Emulsified Asphalt, which would limit VOC emissions from asphalt off-gassing.
Table 3.2-6 presents the estimated maximum daily construction emissions generated during construction of the project. Details of the emission calculations are provided in Appendix B.
Table 3.2-6
Estimated Maximum Daily Construction Criteria Air Pollutant Emissions - Unmitigated Year
VOC NOx CO SOx PM10 PM2.5
Pounds per day
2023 1.14 49.40 24.05 0.23 10.09 3.70
2024 33.30 5.98 16.90 0.03 0.74 0.33
Maximum daily emissions 33.30 49.40 24.05 0.23 10.09 3.70 Emission threshold 75 250 550 250 100 55
Threshold Exceeded? No No No No No No
Notes: VOC = volatile organic compound; NO x = oxides of nitrogen ; CO = carbon monoxide; SO x = sulfur oxides ; PM10 = particulate matter with an aerodynamic diameter equal to or less than 10 microns ; PM2.5 = particulate matter with an aerodynamic diameter equal to or less than 2.5 microns.
See Appendix B for complete results.
The values shown are the maximum summer or winter daily emissions results from CalEEMod. Although not considered mitigation, these estimates reflect the “mitigated” CalEEMod results in order to account for SDAPCD Rule 55 - Fugitive Dust Control, assuming watering of the project site two times per day, use of low-VOC architectural coatings (i.e., no more than 50 grams per liter VOC content) for building interiors and exteriors, and that all diesel -powered off -road equipment over 50 horsepower would meet Tier 4 Final emission standards.
As shown in Table 3.2-6, maximum daily construction emissions would not exceed the significance thresholds for VOC, NOx, CO, SOx, PM10, or PM2.5 during construction.
Operational Emissions
Following the completion of construction activities, the project would generate VOC, NOx, CO, SOx, PM10, and PM2.5 emissions from mobile sources, including vehicular traffic; energy sources from natural gas usage; area sources, (including the use of landscaping equipment, consumer products, and from architectural coatings); and off-road equipment (one CNG forklift). As discussed in Section 3.2.3, under Operational Emissions, pollutant emissions associated with long -term operations were quantified using CalEEMod using a combination of project-specific information and CalEEMod default values (CAPCOA 2021).
Table 3.2-7 presents the maximum daily area, energy, and mobile source emissions associated with project operation. Details of the emission calculations are provided in Appendix B.
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Table 3.2-7
Estimated Operational Criteria Air Pollutant Emissions - Unmitigated Emission Source
VOC NOx CO SOx PM10 PM2.5
Pounds per day
Area 1.55 <0.01 0.01 0.00 <0.01 <0.01
Energy 0.01 0.07 0.06 <0.01 0.01 0.01
Mobile 0.50 0.88 9.60 0.04 4.47 1.20
Off-road 0.04 1.92 19.12 <0.01 0.04 0.04
Total 2.10 2.86 28.79 0.04 4.51 1.24
Emission Threshold 75 250 550 250 100 55
Threshold
Exceeded?
No No No No No No
Notes: VOC = volatile organic compound; NO x = oxides of nitrogen ; CO = carbon monoxide; SO x = sulfur oxides ; PM10 = particulate matter with an aerodynamic diameter equal to or less than 10 microns ; PM2.5 = particulate matter with an aerodynamic diameter equal to or less than 2.5 microns; <0.01 = reported value less than 0.01; negative values are presented in parentheses.
See Appendix B for complete results. Totals may not sum due to rounding.
As shown in Table 3.2-7, the maximum daily emissions of the project would not exceed the significance thresholds for any criteria air pollutants.
As discussed within Section 3.2.1, Existing Conditions, under Regional and Local Air Quality Conditions, the SDAB has been designated as a federal nonattainment area for O3 and a state nonattainment area for O3, PM10, and PM2.5. The nonattainment status is the result of cumulative emissions from various sources of air pollutants and their precursors within the SDAB, including motor vehicles, off -road equipment, and commercial and industrial facilities. Construction and operation of the project would generate VOC and NO x emissions (which are precursors to O 3) and emissions of PM 10 and PM 2.5.
However, as indicated in Tables 3.2-6 and 3.2-7, project-generated construction and operational emissions would not exceed the emission-based significance thresholds for VOC, NOx, PM10, or PM2.5.
Cumulative localized impacts would potentially occur if a construction project were to occur concurrently with another off-site project. Construction schedules for potential future projects near the project area are currently unknown; therefore, potential construction impacts associated with two or more simultaneous projects would be considered speculative. However, future projects would be subject to CEQA and would require air quality analysis and, where necessary, mitigation if the project would exceed applied thresholds. Criteria air pollutant emissions associated with construction activity of future projects would be reduced through implementation of control measures required by the SDAPCD. For example, cumulative PM 10 and PM 2.5 emissions would be reduced because all future projects would be subject to SDAPCD Rule 55 (Fugitive Dust), which sets forth general and specific requirements for all construction sites in the SDAB. In addition, cumulative VOC emissions would be subject to SDAPCD Rule 67.0.1, Architectural Coatings.
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Based on the project-generated construction and operational emissions of VOC, NOx, PM10, and PM2.5, the project would not result in a cumulatively considerable increase in emissions of nonattainment pollutants. Therefore, the project’s cumulative air quality impact would be less than significant.
Threshold #3: Would the project expose sensitive receptors to substantial pollutant concentrations? Air quality varies as a direct function of the amount of pollutants emitted into the atmosphere, the size and topography of the air basin, and the prevailing meteorological conditions. Air quality problems arise when the rate of pollutant emissions exceeds the rate of dispersion. Reduced visibility, eye irritation, and adverse health impacts on those persons termed “sensitive receptors” are the most serious hazards of existing air quality conditions in the area. Some land uses are considered more sensitive to changes in air quality than others, depending on the population groups and the activities involved. People most likely to be affected by air pollution, as identified by CARB, include children, older adults, athletes, and people with cardiovascular and c hronic respiratory diseases; however, for the purposes of this analysis, residents are also considered sensitive receptors. As such, sensitive receptors include residences, schools, playgrounds, childcare centers, athletic facilities, long -term healthcare facilities, rehabilitation centers, convalescent centers, and retirement homes. As described previously, the nearest existing sensitive receptors are located to the west of the project site, with multifamily residential (520 feet away) and Bradley Park (550 feet away) the most proximate.
Health Impacts of Carbon Monoxide
Mobile source impacts occur on two scales of motion. Regionally, project-related travel would add to regional trip generation and increase the vehicle miles traveled within the local airshed and the SDAB.
Locally, project generated traffic would be added to the County’s roadway system near the project site.
If such traffic occurs during periods of poor atmospheric ventilation, is composed of a large number of vehicles “cold-started” and operating at pollution -inefficient speeds, and is operating on roadways already crowded with non -project traffic, there is a potential for the formation of microscale CO hotspots in the area immediately around points of congested traffic. Because of continued improvement in vehicular emissions at a rate faster than the rate of vehicle growth and/or congestion, the potential for CO hotspots in the SDAB is steadily decreasing.
CO transport is extremely limited and CO disperses rapidly with distance from the source. Under certain extreme meteorological conditions, however, CO concentrations near a congested roadway or intersection may reach unhealthy levels, affecting sensitive r eceptors such as residents, school children, hospital patients, and the elderly. Typically, high CO concentrations are associated with urban roadways or intersections operating at an unacceptable level of service. Projects contributing to adverse traffic impacts may result in the formation of CO hotspots.
To verify that the project would not cause or contribute to a violation of the CO standards, a screening evaluation of the potential for CO hotspots was conducted using the County of San Diego screening
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threshold of 3,000 peak trips (County of San Diego 2007). The trip rates for the project are based on driveway counts for the existing Hughes Circuits facility conducted by Chen Ryan in March 2022.
Based on this data, there would be approximately 40 trips during the AM peak hour and 43 trips during the PM peak hour, which would be minimal in comparison to the screening threshold of 3,000 peak trips. Therefore, the project would not result in a CO hotspot and would result in a less than significant impact.
Health Effects of Other Criteria Air Pollutants
Project construction and operation would not exceed significance thresholds for VOC, NO x, CO, SO x, PM10, or PM2.5. VOCs and NOx are precursors to O3, for which the SDAB is designated as nonattainment with respect to the NAAQS and CAAQS. The health effects associated with O3 are generally associated with reduced lung function. The contribution of reactive organic gases and NOx to regional ambient O3 concentrations is the result of complex photochemistry. The increases in O 3 concentrations in the SDAB due to O3 precursor emissions tend to be found downwind from the source location to allow time for the photochemical reactions to occur. However, the potential for exacerbating excessive O 3 concentrations would also depend on the time of year that the VOC emissions would occur because exceedances of the O 3 CAAQS/NAAQS tend to occur April through October when solar radiation is highest. The holistic effect of a single project’s emissions of O 3 precursors is speculative due to the lack of reliable and meaningful quantitativ e methods to assess this impact. The project would not exceed the significance thresholds for VOC or NO x; therefore, implementation of the project would contribute minimally to regional O3 concentrations and the associated health effects.
In addition to O3, NOx emissions contribute to potential exceedances of the NAAQS and CAAQS for NO2 (since NO 2 is a constituent of NO x). Health effects that result from NO 2 and NO x include respiratory irritation, which could be experienced by nearby receptors during the periods of heaviest use of off - road construction equipment. However, project construction would be relatively short term, and off - road construction equipment would be operating at various portions of the site and would not be concentrated in one portion of the site at any one time. In addition, existing NO2 concentrations in the area are well below the NAAQS and CAAQS standards. Because project generated NOx emissions would not exceed the significance threshold, the project would not result in potential health effects associated with NO2 and NOx.
CO tends to be a localized impact associated with congested intersections. The associated potential for CO hotspots were discussed previously and were determined to be a less -than-significant impact.
Furthermore, the existing CO concentrations in the area are well below the NAAQS and CAAQS standards. Thus, the project’s CO emissions would not contribute to significant health effects associated with this pollutant.
Construction and operation of the project would also not exceed thresholds for PM 10 or PM 2.5 and would not contribute to exceedances of the NAAQS and CAAQS for particulate matter or would obstruct
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the SDAB from coming into attainment for these pollutants. Additionally, the project would implement dust control strategies and be required to comply with SDAPCD Rule 55, Fugitive Dust Control, which limits the amount of fugitive dust generated during construction. Due to the minimal contribution of particulate matter during construction and operation, the project is not anticipated to result in health effects associated with PM10 or PM2.5.
In summary, the project would not result in any potentially significant contribution to local or regional concentrations of nonattainment pollutants and would not result in a significant contribution to the adverse health impacts associated with those pollutants. Impacts would be less than significant .
Furthermore, there are numerous scientific and technological complexities associated with correlating criteria air pollutant emissions from an individual project to specific health effects or potential additional nonattainment days, and there are currently no modeling tools that could provide reliable and meaningful additional information regarding health effects from criteria air pollutants generated by individual projects.
Health Impacts of Toxic Air Contaminants
In addition to impacts from criteria pollutants, project impacts may include emissions of pollutants identified by the state and federal government as TACs or hazardous air pollutants. State law has established the framework for California’s TAC identifica tion and control program, which is generally more stringent than the federal program and aimed at TACs that are a problem in California. The state has formally identified more than 200 substances as TACs, including the federal hazardous air pollutants, and is adopting appropriate control measures for sources of these TACs. The greatest potential for TAC emissions during construction would be diesel particulate emissions from heavy equipment operations and heavy-duty trucks and the associated health impacts to sensitive receptors.
The following measures are required by state law to reduce DPM emissions:
• Fleet owners of mobile construction equipment are subject to the CARB Regulation for In-use Off-road Diesel Vehicles (13 CCR 2449), the purpose of which is to reduce DPM and criteria pollutant emissions from in-use (existing) off-road diesel-fueled vehicles. • All commercial diesel vehicles are subject to Title 13, Section 2485 of the California Code of Regulations, limiting engine idling time. Idling of heavy-duty diesel construction equipment and trucks during loading and unloading shall be limited to 5 minutes; electric auxiliary power units should be used whenever possible.
Health effects from carcinogenic air toxics are usually described in terms of cancer risk. The SDAPCD recommends an incremental cancer risk threshold of 10 in a million (SDAPCD 2015b). “Incremental cancer risk” is the net increased likelihood that a person continuously exposed to concentrations of TACs resulting from a project over a 9-, 30-, and 70-year exposure period will contract cancer based on the use of standard Office of Environmental Health Hazard Assessment risk -assessment methodology (OEHHA 2015) . The project would not require the extensive operation of heavy -duty
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construction equipment, which is subject to a CARB Airborne Toxics Control Measure for in-use diesel construction equipment to reduce diesel particulate emissions and would not involve extensive use of diesel trucks, which are also subject to a CARB Airbor ne Toxics Control Measure. Furthermore, the project would implement PDF-AQ-1, which requires all equipment greater than 50 horsepower to be Tier 4 Final compliant, which can reduce construction diesel exhaust by 93 % to 96% compare d to equipment with engines meeting Tier 1 or Tier 2 emission standards.6 As shown in Table 3.2-6, maximum daily PM 10 or PM 2.5 emissions generated by construction equipment operation and haul-truck trips during construction, which is based on exhaust and fugitive dust generated by equipment operation and vehicle travel, would be well below the significance thresholds. Moreover, t otal construction of the project would last approximately 12 months, after which project-construction TAC emissions would cease. Thus, the duration of the proposed construction activities would only constitute a small percentage of the total 30-year exposure period.
In regard to long-term TAC emissions, the project would result in a minimal increase in daily truck traffic on the roadway network and would not require stationary sources (such as diesel emergency generators). Therefore, the exposure of project-related TAC emission impacts to proximate sensitive receptors would be less than significant.
Valley Fever
As discussed above in Section 3.2.1, the average incidence rate within the County is below the statewide average. Furthermore, construction of the project would comply with SDAPCD Rule 55, Fugitive Dust Control, which limits the amount of fugitive dust generated during construction. SDAPCD Rule 55 is intended to reduce PM 10 emissions from any transportation, handling, construction, or storage activity that has the potential to generate fugitive dust. Based on the low incidence rate of coccidioidomycosis on the project site and in the County, and with the project’s implementation of dust control strategies, it is not anticipated that earth -moving activities during project construction would result in exposure of nearby sensitive receptors to Valley Fever. Therefore, the project would have a less-than-significant impact with respect to Valley Fever exposure for sensitive receptors.
Threshold #4: Would the project result in other emissions (such as those leading to odors) adversely affecting a substantial number of people?
Based on available information, the project is not anticipated to result in other emissions that have not been addressed under Threshold 1 through Threshold 3 above. As such, this analysis focuses on
6 Particulate matter (PM) emissions benefits are estimated by comparing off-road PM emission standards for Tier 1 and Tier 2 with Tier 4 final emissions standards. Tier 1 PM emissions standards were established for equipment with 25 -< 50 horsepower and equipment with horsepower < 175. Tier 1 emissions standards for these engines were compared against Tier 4 Final emissions standards, resulting in a 96 % reduction in PM. The U.S. EPA established PM standards for engines with horsepower between 50 -< 175 as part of the Tier 2 emission standards. For these engines Tier 2 emissions standards were compared against Tier 4 Final emissions standards, resulting in between 93% and 95% reduction in PM.
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the potential for the project to generate odors. The occurrence and severity of potential odor impacts depends on numerous factors. The nature, frequency, and intensity of the source; the wind speeds and direction; and the sensitivity of receiving location each contribute to the intens ity of the impact.
Although offensive odors seldom cause physical harm, they can be annoying and cause distress among the public and generate citizen complaints. Odors would also be controlled through compliance with SDAPCD Rule 51 (Nuisance), which prohibits the discharge, from any source, of such quantities of air contaminants or other materials that cause or have a tendency to cause injury, detriment, nuisance, annoyance to people and/or the public, or damage to any business or property.
Odors would be generated from vehicles and/or equipment exhaust emissions during construction of the project. Odors produced during construction would be attributable to concentrations of unburned hydrocarbons from tailpipes of construction equipment and architectural coatings. Such odors would disperse rapidly from the project site and generally occur at magnitudes that would not affect substantial numbers of people. Therefore, impacts associated with odors during construction would be less than significant.
Land uses and industrial operations associated with odor complaints include agricultural uses, wastewater treatment plants, food processing plants, chemical plants, composting, refineries, landfills, dairies, and fiberglass molding. The project would not engage in any of these activities.
Therefore, the project would result in an odor impact that is less than significant.
3.2.5 Cumulative Impact Analysis
See Threshold #2 in Section 3.2.4, Project Impact Analysis, above, for a detailed discussion of the project’s cumulative air quality impacts. In analyzing cumulative impacts from the project, the analysis must specifically evaluate a project’s contribution to the cumulative increase in pollutants for which the basin is designated as nonattainment for the CAAQS and NAAQS.
Implementation of the project would not result in a cumulatively considerable increase in emissions of nonattainment pollutants. Therefore, cumulative impacts would be less than significant.
3.2.6 Mitigation Measures
The project would not result in significant impacts; therefore, no mitigation is required.
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3.2.7 Conclusion
The project would be consistent with the land use and zoning designation of the project site . The project’s proposed growth would be within the growth projections for the City and, at a regional level, the project is consistent with the underlying growth forecasts in the SIP and RAQS. Therefore, implementation of the project would not conflict with the RAQS or SIP and proposed development would be consistent with the growth in the region.
Implementation of the project also would not violate any air quality standards or contribute substantially to an existing or projected air quality violation during construction or operation.
Additionally, the project would not expose sensitive receptors to substantial pollutant concentrations or expose a substantial number of people to objectionable odors. In summary, impacts with regard to air quality would be less than significant, and no mitigation is required.
3.3 Biological Resources
Hughes Circuits Project Environmental Impact Report May 2024 City of San Marcos 3.3-1
3.3 BIOLOGICAL RESOURCES
This section describes the existing biological resources of the Hughes Circuits Project (project) , identifies associated regulatory requirements, evaluates potential impacts, and identifies mitigation measures related to implementation of the project. This section is based on the Biological Resources Technical Report, prepared by Dudek in September 2022, which is included as Appendix C to this environmental impact report (EIR).
Table 3.3-1 summarizes the project- and cumulative-level biological resource impacts, by threshold.
Table 3.3-1
Biological Resources Summary of Impacts
Threshold of Significance Project Impact
Project
Cumulative
Impact
Significance
Determination
#1 - Have a substantial adverse effect, either
directly or through habitat modifications, on
any species identified as a candidate, sensitive,
or special status species in local or regional
plans, policies, or regulations, or by the
California Department of Fish and Wildlife or
U.S. Fish and Wildlife Service.
Potentially
Significant
Less than
Significant with
Mitigation
Less than
Significant with
Mitigation
#2 - Have a substantial adverse effect on any
riparian habitat or other sensitive natural
community identified in local or regional plans,
policies, regulations or by the California
Department of Fish and Wildlife or U.S. Fish
and Wildlife Service.
Potentially
Significant
Less than
Significant with
Mitigation
Less than
Significant with
Mitigation
#3 - Have a substantial adverse effect on state
or federally protected wetlands (including, but
not limited to, marsh, vernal pool, coastal, etc.)
through direct removal, filling, hydrological
interruption, or other means.
Potentially
Significant
Less than
Significant with
Mitigation
Less than
Significant with
Mitigation
#4 - Interfere substantially with the movement
of any native resident or migratory fish or
wildlife species or with established native
resident or migratory wildlife corridors, or
impede the use of native wildlife nursery sites.
Less than
Significant
Less than
Significant
Less than
Significant
#5 - Conflict with any local policies or
ordinances protecting biological resources,
such as a tree preservation policy or ordinance.
Less than
Significant
Less than
Significant
Less than
Significant
#6 - Conflict with the provisions of an adopted
Habitat Conservation Plan, Natural Community
Conservation Plan, or other approved local,
regional, or state habitat conservation plan.
Less than
Significant
Less than
Significant
Less than
Significant
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3.3.1 Existing Conditions
The 10.8610.46-acre project site consists of one undeveloped lot on two parcels (A ssessor’s Parcel Numbers 219-223-20-00 and 219 -223-22-00). Off-site improvements total 0.28 acres. Although undeveloped, the project site reflects a history of disturbance. The on -site land use is currently unoccupied and undeveloped apart from two 100-foot-wide parcels an approximately 108-foot-wide San Diego County Water Authority dirt right -of-way lane owned by the San Diego Water Authority bisecting the project property. The project site consists of mostly undeveloped lands, with a mix of native and non-native vegetation communities.
The project site is immediately adjacent to roadways . The site is located at the northeast corner of South Pacific Street. South Pacific Street abuts the site’s western and southern boundary. Adjacent land uses include mixed commercial development to the north and south, a public recreational park (Bradley Park) to the west, and undeveloped land to the east.
Elevation ranges from approximately 520 feet above mean sea level in the eastern portion of the review area to 535 feet above mean sea level in the northwest portion of the review area. The U.S. Department of Agriculture Soil Survey mapped the project area as predominantly underlain by the following soil types:
Las Flores loamy fine sand, 2% to 9% slopes (LeC) and Placentia sandy loam, thick surface, 0% to 2% slopes (PfA), which are both listed as hydric soils (USDA 2020a, 2021) (Appendix C).
3.3.1.1 Planning Context
The City of San Marcos (City) Subarea Habitat Conservation Plan/Natural Community Conservation Plan (NCCP) (Subarea Plan) has not been finalized or implemented, and the City is no longer an active participant in the NCCP program and the subregional Multiple Habitat Conservation Program (MHCP) conservation planning effort. However, it is the City ’s policy to comply with the conservation policies identified in the Draft San Marcos Subarea Plan, including an assessment of designated Biological Core Linkage Area or MHCP Focused Planning Area in the context of the project. In addition, the project will be evaluated to ensure consistency with the California Environmental Quality Act (CEQA).
The City of San Marcos Municipal Code was reviewed and contains additional environmental standards for the City environmental review process in Title 18, which defines how the City will define environmental protection and the steps thereafter ( Appendix C ). The site is designated as Light Industrial in the General Plan (City of San Marcos 2012).
3.3.1.2 Vegetation Communities
Thirteen vegetation communities or land cover types occur within the project site: Arundo-dominated riparian, disturbed wetland, emergent wetland, San Diego mesa claypan vernal pool, southern willow scrub, tamarisk scrub, valley needlegrass grassland, wildflower field, Diegan coastal sage scrub,
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Diegan coastal sage scrub -Baccharis dominated, non -native grassland (broadleaf dominated ), eucalyptus woodland, and disturbed habitat (see Table 3.3 -2, Existing Vegetation Communities and Land Cover Types). Vegetation community locations on the project site can be seen in Figure 3.3-1, Vegetation Communities and Land Covers.
Table 3.3-2
Existing Vegetation Communities and Land Cover Types
Vegetation Community/Land Cover On-Site Acreage Off-Site Acreage Group A. Wetlands Communities
Arundo-Dominated Riparian 0.11 0.01
Disturbed Wetland 0.11 0
Emergent Wetland 0.59 0
San Diego Mesa Claypan Vernal Pool 0.43 0
Southern Willow Scrub 0.03 0
Tamarisk Scrub 0.58 0
Subtotal Group A. Wetlands Communities 1.84 0.01
Group B. Rare Uplands
Valley Needlegrass Grassland 3.633.51 0
Wildflower Field 1.901.85 0
Subtotal Group B. Rare Uplands 5.535.36 0
Group C. Coastal Sage Scrub
Diegan Coastal Sage Scrub 1.080.96 0.01
Diegan Coastal Sage Scrub—Baccharis-dominated 1.481.39 0.04 Subtotal Group C. Coastal Sage Scrub 2.562.35 0.05
Group D. Annual Grasslands
Non-native Grassland—Broadleaf-Dominated 0.07 0
Subtotal Group D. Annual Grasslands 0.07 0
Group F. Other Lands
Disturbed Habitat 0.610.59 0.22
Eucalyptus Woodland 0.25 0
Subtotal Other Lands 0.860.84 0.22
Total* 10.8610.46 0.28
Note:
* Totals may not sum due to rounding
Arundo-Dominated Riparian
Arundo-dominated riparian thickets are dominated almost exclusively by giant reed ( Arundo donax).
This designation is only used when giant reed accounts for greater than 50% of the total vegetative cover within a mapping unit. Site factors include loose, sandy, or fine gravelly alluvium near streams or channels. Typically, giant reed occurs along major rivers of coastal Southern California (Oberbauer et al. 2008). Arundo-dominated riparian on site consists of almost 100% cover of giant reed with no other plant diversity where it occurs. The edge s of the Arundo community consist of iceplant
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(Carpobrotus edulis). Arundo-dominated riparian occupies 0.11 acres on site and 0.01 acres off site (Appendix C).
Disturbed Wetland
Disturbed wetlands are areas permanently or periodically inundated by water that have been significantly modified by human activity. This includes portions of wetlands with obvious artificial structures such as concrete lining, barricades, riprap, piers, o r gates. Often unvegetated, areas may contain scattered native or non -native vegetation. Characteristic species include saltcedar (Tamarix spp.), eucalyptus ( Eucalyptus spp.), palms ( Phoenix spp. and Washingtonia spp.), and pampas grass (Cortaderia spp.). Disturbed wetland on site consists of riprap and barricades, likely set up by transients to the area. A few hottentot-fig are also found within this area. The disturbed wetland also contains patches of annual beard grass (Polypogon monspeliensis), curly dock (Rumex crispus), and a variety of willowherb ( Epilobium spp.). Disturbed wetland occupies 0.11 acre s on site (Appendix C).
Emergent Wetland
Emergent wetlands are generally persistent wetlands that are dominated by low -growing perennial wetland species. Emergent wetlands can be found in channels, seeps, springs, floodplains, margins of lakes or rivers, and various basins such as pools, ponds, meadows, and dune swales. They may be freshwater or alkali wetlands. Associated species include sedge (Carex spp.), spikerush ( Eleocharis spp.), rush ( Juncus spp.), dock ( Rumex spp.) and a variety of others. Emergent wetlands are found throughout San Diego County in areas that are wet (Oberbauer et al. 2008).
Emergent wetland is found next to the tributary on the eastern side of the project site where the tributary consistently overflows. The emergent wetland is dominated by pale spikerush ( Eleocharis macrostachya), Mexican rush ( Juncus mexicanus), and iris -leaf rush ( J. xiphioides). Less commonly found within the emergent wetland are curly dock and alkali mallow ( Malvella leprosa). On the far western side of the project site, the emergent wetland consists almost entirely of Mexican rush and broad-leaved cattail (Typha latifolia ). Pickleweed ( Salicornia pacifica ) flats occupy portions of this emergent alkali wetland. This community on site is best described as pickleweed flats because no other species occur in this section. Emergent wetland occupies 0.59 acres on site (Appendix C).
San Diego Mesa Claypan Vernal Pool
Vernal pools are seasonally flooded depressions that support a distinctive living community adapted to extreme variability in hydrologic conditions (e.g., seasonally very dry and very wet conditions).
Functional vernal pools have an impermeable (or nearly impermeable) soil or subsoil layer, which prevents water from percolating downward causing rainfall inputs and/or surface runoff to become trapped or ‘perched’ above the impermeable (or nearly impermeable) soil or subsoil layer of the pool
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feature. Although vernal pools are often associated with hummocks or mima -mounds, this feature is not always present. Vernal pools can be differentiated from other temporary wetlands by the following criteria: (1) the basin is at least partially vegetated during the normal growing season or is unvegetated due to heavy clay or hardpan soils that do not support plant growth; and (2) the basin contains at least one vernal pool indicator species (e.g., woolly-marbles [ Psilocarphus spp.], toothed calicoflower [Downingia cuspidata], San Diego button -celery [Eryngium aristulatum var. parishii], or crustaceans [Branchinecta spp., Streptocephalus spp., and others]) (Oberbauer et al. 2008).
Because vernal pool plants and animals are restricted to vernal pool ecosystems, presence or absence of the above -mentioned plant and animal species can define a vernal pool. Many of the extant vernal pools are threatened by grazing, invasive weeds, fragme ntation, vehicular traffic, and urbanization. This vegetation community is considered sensitive by various local, state, and federal resource agencies including the U.S. Army Corps of Engineers ( USACE) and U.S. Fish and Wildlife Service (USFWS).
The site has distinctive mima-mound formation with lower areas having vernal pools and each vernal pool documented thus far has several vernal pool/wetland indicator species present. Due to time constraints, all vernal pools are not mapped on site. The following species were found within the vernal pools documented on site for this reconnaissance survey: San Diego button celery federally and state endangered), spreading navarretia (Navarretia fossalis; federally threatened), Mexican rush), irisleaf rush, an nual coast plantago ( Plantago elongata ), aquatic pygmy plant ( Crassula aquatica ), pale spikerush, toad rush (Juncus bufonius), and smooth boisduvalia (Epilobium campestre). Some of the vernal pools had an abundance of San Diego button celery where populations were expanding outside the vernal pool basins. San Diego Mesa Claypan Vernal Pool complex occurs across the central and eastern portions of the site and occupies 0.43 acres (Appendix C).
Southern Willow Scrub
Southern willow scrub is a dense broad-leafed, winter deciduous vegetation community. The riparian thickets where southern willow scrub is found are dominated by willow ( Salix spp.) with scattered emergent western sycamore (Platanus racemosa) and Fremont cottonwood ( Populus fremontii ssp. fremontii). Stands are too dense for understory species. Site factors include loose, sandy, or fine gravelly alluvium deposited near stream channels during flood flows (Oberbauer et al. 2008).
Southern willow scrub on site is dense and lacks understory species. Southern willow scrub is near the sidewalk and contiguous to the tributary on the western side of the site. The willow species that dominates this vegetation community is red willow ( Salix laevigata). Southern willow scrub occupies
0.03 acres on site (Appendix C).
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Tamarisk Scrub
Tamarisk scrub is a weedy, virtual monoculture of any of several tamarisk species. Tamarisk usually supplants native vegetation following disturbance. Typically, tamarisk scrub creates a braided wash or is found in intermittent streams, often in areas where high evaporation increases the streams saltiness. Tamarisk is a strong phreatophyte and a prolific seeder. This makes tamarisk a strong competitor to other wetland species (Oberbauer et al. 2008).
The tamarisk on site dominates the tree canopy creating a monoculture. However, a variety of herbs are found in the understory of the tamarisk on site. The ground is comp osed of herbaceous wetland species. The most abundant is rabbit’s foot grass, and in some sections, pickleweed. Tamarisk scrub vegetation occupies 0.58 acres on site (Appendix C).
Valley Needlegrass Grassland
Valley needlegrass grassland is a grassland with perennial tussock formed by needlegrass (Stipa spp.).
Native and introduced annuals occur between the perennials and often exceed the bunchgrass cover.
In San Diego County, native perennial herbs such as sanicle (Sanicula spp.), checkerbloom (Sidalcea spp.), blue-eyed grass (Sisyrinchium spp.), poppy (Eschscholzia spp.), and goldfields (Lasthenia spp.) are present. The percent cover of native species at any one time may be quite low but an area is considered native grassland if 20% aerial cover of native species is present. Valley needlegrass grassland usually occurs on fine -textured clay soils, moist or even waterlogged soils but can be very dry over the winter (Oberbauer et al. 2008).
The valley needlegrass grassland makes up the mima-mound formations on site and other open areas.
This community is covered with patches of purple needlegrass ( Stipa pulchra ), native annuals including western blue-eyed grass ( Sisyrinchium bellum), goldenstar (Bloomeria spp.) and brodiaea (Brodiaea spp.), and non -native redstem stork’s bill ( Erodium cicutarium). In addition, a variety of tarplants (Holocarpha spp.) are also present throughout the needlegrass fields. Valley needlegrass grassland dominated habitat occupies 3.633.51 acres on site (Appendix C).
Wildflower Field
Wildflower fields are an amorphous composition of mostly native, herb-dominated types of wildflowers.
Wildflower fields can be noted for conspicuous annual wildflower displays. Dominance varies from site to site and from year to year at a particular site. In San Diego County, wildflower fields can be associated with creosote bush (Larrea tridentata) scrub, wet meadows, foothill or perennial grassland, and coastal mesas (Oberbauer et al. 2008) . On site, wildflower fields are dominated by a variety of wildflowers including those in the Themidaceae family, such as goldenstar and brodiaea species. In addition, blue-eyed grass, small-flowered morning glory (Convolvulus simulans), and graceful tarplant (Holocarpha virgata ssp. elongata ) take up large sections of the wildflower fields. Few non -native
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species occur in these areas, and many of these wildflowers are rare species. Wildflower fields occupy
1.901.85 acres on site (Appendix C).
Diegan Coastal Sage Scrub
Diegan coastal sage scrub is a native vegetation community that, according to Oberbauer et al. (2008), is composed of a variety of soft, low, aromatic shrubs, characteristically dominated by drought - deciduous species —such as California sagebrush ( Artemisia californica ), California buckwheat (Eriogonum fasciculatum ), and sages (Salvia spp.)—with scattered evergreen shrubs, including lemonade berry (Rhus integrifolia) and laurel sumac (Malosma laurina). The average height of coastal sage scrub reaches 3 to 4 feet.
Diegan coastal sage scrub occurs within the central and eastern sections of the site. Dominant species on site include deerweed (Acmispon glaber), Menzies’ goldenbush (Isocoma menziesii), and blue-eyed grass. Less commonly occurring species include California sagebrush ( Artemisia californica ) and California buckwheat (Eriogonum fasciculatum). Diegan coastal sage scrub occupies 1.080.96 acres on site and 0.01 acres off site (Appendix C).
Diegan Coastal Sage Scrub-Baccharis Dominated
The Diegan coastal sage scrub–Baccharis dominated vegetation community is similar to coastal sage scrub but is dominated by baccharis (Baccharis spp.). This vegetation community usually occurs where soils are nutrient poor and disturbance is present, where it typically fills in areas after high levels of disturbance (Oberbauer et al. 2008).
This vegetation community exists within the far eastern section of the site and near the southcentral portion of the site in greatest abundance. Broom baccharis ( Baccharis sarothroides ) makes up approximately 80% of the vegetation within this community on site. The understory of this community consists of a variety of other species. Less commonly occurring species occurring within the understory of broom baccharis include annual yellow sweetclover (Melilotus indicus ), blue -eyed grass, black mustard (Brassica nigra), Menzies’ goldenbush, deerweed, and iceplant. Diegan coastal sage scrub– Baccharis dominated occupies 1.48 acres on site and 0.04 acres off site (Appendix C).
Non-Native Grassland-Broadleaf Dominated
Non-native grassland consists of dense to sparse cover of non -native invasive broadleaf species (Oberbauer et al. 2008). This designation is used when non -native invasive broadleaf species make up more than 50% cover of the vegetation community. In San Die go County, the presence of black mustard and shortpod mustard ( Hirschfeldia incana) are common indicators of this community. In some areas, depending on past disturbance and annual rainfall, some mustards are more abundant than others (Oberbauer et al. 2008).
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Non-native grassland-broadleaf dominated is disturbed on site and consists mostly of black mustard.
Less commonly occurring species include stinkwort (Dittrichia graveolens) with red brome (Bromus rubens) and stork ’s bill (Erodium spp.). A few of these areas occur on top of the mima mound formations but seem to have been graded or disturbed so heavily they can be considered non -native broadleaf communities. Non-native grassland—broadleaf dominated habitat occupies 0.07 acre s on site (Appendix C).
Disturbed Habitat
Disturbed habitat are areas that have been physically disturbed and are no longer recognizable as a native or naturalized vegetation association (Oberbauer et al. 2008). These areas may continue to retain a soil substrate. If vegetation is present, it is almost entirely composed of non-native vegetation, such as ornamentals or ruderal exotic species. Examples of these areas may include graded landscapes, graded firebreaks, graded construction pads, temporary construction staging areas, off- road-vehicle trails, areas repeatedly cleared for fuel management, or areas that are repeatedly used in ways that prevent revegetation (e.g., parking lots, trails that have persisted for years).
Ornamental vegetation occurs right next to the sidewalk and covers the land up to the salt cedar community. It also invades some of the understory of the eucalyptus woodland. On site, this community consists almost entirely of ornamental vegetation or iceplant, with small sections of non-native annual stinkwort. Disturbed habitat within off -site areas is primarily void of vegetation. Disturbed habitat occupies 0.610.59 acres on site and 0.22 acres off site (Appendix C).
Eucalyptus Woodland
Eucalyptus habitats range from single-species thickets with little or no shrubby understory to scattered trees over a well -developed herbaceous shrubby understory. Eucalyptus species can form a dense stand with a closed canopy or an open stand that may be installed as a windbreak or ornamental plantings. Eucalyptus species produce a large amount of leaf and bark litter. Overstory composition is typically limited to one species of the genus, or mixed stands composed of several eucalyptus species; few native overstory species are present within eucalyptus-planted areas. Some characteristic species of this community include blue gum (Eucalyptus globulus) and red gum (E. camaldulensis) (Oberbauer et al. 2008).
Eucalyptus woodland is composed of red gum and red iron bark (E. sideroxylon) on site and would be considered a dense closed-canopy stand. This eucalyptus woodland community can be easily observed on aerial photography within the site. Eucalyptus woodland occupies 0.25 acres on site (Appendix C).
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3.3.1.3 Floral Diversity
A total of 131 species of vascular plants, consisting of 81 native species (62%) and 50 non -native species (38%), were recorded during the initial survey and vegetation mapping effort. A list of all plant species observed during 2019/2020 and 2023 surveys is provided in Appendix A, Plant Compendium, of the Biological Resources Technical Report (Appendix C).
3.3.1.4 Animals
A total of 29 wildlife species were observed in the survey area, 28 of which are native species. A cumulative list of wildlife species observed within the project site is presented in Appendix B, Wildlife Compendium, of Appendix C . Special -status wildlife incidentally observed include: Cooper ’s hawk (Accipiter cooperii) (California Department of Fish and Wildlife [CDFW] Watch List) and white-tailed kite (Elanus leucurus ) (CDFW fully protected species). During the field reconnaissance study, Dudek biologists observed and heard the federally endangered least Bell’s vireo throughout the assessment moving into the vernal pool areas from willow riparian along the southeastern portion of the study area (Figure 3.3-2, Special-Status Plants and Wildlife ). No aquatic or amphibious species were observed during all survey efforts.
3.3.1.5 Special-Status/Regulated Resources
Sensitive Vegetation Communities/Habitats
Sensitive vegetation communities/habitat types are defined as land areas that support unique vegetation communities or the habitats of rare or endangered species or subspecies of animals or plants as defined by Section 15380 of the State CEQA Guidelines. The MHCP organizes vegetation into habitat group types: Wetland Communities, Rare Upland, Coastal Sage Scrub, Chaparral, Annual Grassland, and Other (AMEC Earth & Environmental et al. 2003). Varying mitigation ratios are required for each habitat group except “other.”
Eleven sensitive vegetation communities/habitat types were mapped on the project site: arundo- dominated riparian, disturbed and emergent wetland, San Diego Mesa Claypan vernal pool, southern willow scrub, tamarisk scrub, Diegan coastal sage scrub (including baccharis -dominated), valley needlegrass grassland, wildflower field, and non-native grassland (broadleaf-dominated). Remaining areas on the project site include disturbed habitat and eucalyptus woodland , which are not considered sensitive.
Special-Status Plant Species
Endangered, rare, or threatened plant species, as defined in CEQA Guidelines Section 15380(b) (14 CCR 15000 et seq.), are referred to as “special -status plant species” in this report and include
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(1) endangered or threatened plant species recognized in the context of the California Endangered Species Act (CESA) and the federal Endangered Species Act (FESA) (CDFW 2018), and (2) plant species with a California Rare Plant Rank (CRPR) 1 through 3 (Appendix C). This report also includes CRPR 4 plant species.
A special-status plant survey was conducted for the project site on May 24 and August 30, 2021 , to determine the presence or absence of special-status plant species. An updated survey focusing on the potential change in Brodiaea populations was conducted in June 2023. A list of potentially occurring plants was generated as part of the literature review (Appendix C). Appendix C provides a list of all special-status plant species with their habitat requirements and potential to occur in the project site.
This table provides evaluations for each of the special-status species’ occurrence in the vicinity of the project site and their potential to occur in the project area based on known geographic range, habitat associations, preferred soil substrate, life form, elevation, and blooming period. S pecial-status plant species that have low potential or are not expected to occur on site are not further analyzed in this report because no direct, indirect, or cumulative impacts are expected based on the negative surveys and evaluation that these species do not have a moderate or high potential to occur in the project site.
Based on a review of the potential species to occur within the region, the habitat conditions identified in the project boundary, and the results of focused botanical surveys conducted in the project area, at total of 24 special -status, rare, and/or sensitive plant species have a moderate or high potential to occur. Of those, the following special-status plant species were observed within the wildflower fields and vernal pool communities during the initial biological reconnaissance and subsequent focused rare plant surveys:
• San Diego button celery ( Eryngium aristulatum var. parishii )—federally endangered, state endangered, CRPR 1B.1
• thread-leaved brodiaea (Brodiaea filifolia)—federally threatened, state endangered, CRPR 1B.1 • spreading navarretia (Navarretia fossalis)—federally threatened, CRPR 1B.1 • Orcutt’s brodiaea (Brodiaea orcuttii)—CRPR 1B.1
The above-referenced special-status plant species and focused rare plant survey results for each are described in further detail below. The following plant species were detected, but are not considered special-status under CEQA:
• small-flowered morning glory (Convolvulus simulans)— CRPR 4.2 • graceful tarplant (Holocarpha virgata var. elongata)— CRPR 4.2 San Diego Button Celery
This federally and state endangered, CRPR 1B.1 dicot occurs in freshwater wetlands and vernal pool habitats as well as within coastal sage scrub, valley and foothill grassland, and riparian communities.
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This wetland indicator species blooms from April to June between 65 and 2,035 feet above mean sea level. Hundreds of individuals were observed surrounding the San Diego mesa claypan vernal pools in the center of the project site (see Figure 3.3-2). Some of the vernal pools had San Diego button-celery populations that were expanding outside the vernal pool basins.
Thread-Leaved Brodiaea
Thread-leaved brodiaea is a federally threatened , state endangered, CRPR 1B.1 Southern California endemic monocot. This species prefers open ground such as f loodplains, grasslands, and gentle hillsides, particularly near vernal pools. It only blooms in the spring of good rainfall years (March through June) between 100 and 2,500 feet above mean sea level , in clay or semi -sandy soils.
Hundreds of individuals were observed on the central portion of the project site within the valley needlegrass grassland and wildflower field habitats (Figure 3.3-2).
With the greater than average rainfall of the 2022 /2023 season in Southern California, most native bulb species showed better than average population extent and numbers, and this was also the case for the Brodiaea surveys conducted on the project in 2023. The extent of thread -leaf brodiaea were similar to the surveys in 2021, with approximately 500 individuals of thread-leaf brodiaea documented during the 2023 survey. In some areas there were overlapping occurrences of Orcutt’s brodiaea and thread-leaf brodiaea. In these areas, there were a few potential hybrid individuals documented.
Hybrids between Orcutt ’s brodiaea and thread -leaf brodiaea are known to occur infrequently, especially in the San Marcos valley area. Where Orcutt’s brodiaea has no staminodes (a remnant sterile stamen) in the flowers and thread -leaf brodiaea has thin pointed staminodes in the flowers, these hybrids often exhibit a thin pointed staminode like structure that remains fused within the inside of the petal. Whenever these potential hybrids were found, it was assumed that these individuals were closest aligned with the thread leaf brodiaea populations and were mapped as such.
Spreading Navarretia
This federally threatened, CRPR 1B.1 annual herb is native to southern California. It occurs strictly in vernal pool and shallow freshwater habitats and blooms from April to June from 100 to 2,150 feet above mean sea level. Approximately 48 individuals were observed within the central portion of the project site in association with San-Diego button celery within the northern central portion of the study area.
Orcutt’s Brodiaea
Orcutt’s brodiaea is a CRPR 1B.1 Southern California native perennial herb that blooms from May to July and occurs from 98 to 5,550 feet above mean sea level. Its preferred habitat consists of vernally moist grasslands and the periphery of vernal pools. In 2021, hundreds of individuals were observed predominantly in the central portion of the project site, within the wildflower fields and valley needlegrass grassland communities. Additionally, individuals were observed scattered along the vernal pool habitats
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and wildflower fields along the northeastern and southeastern portions of the project site. During the 2023 focused survey. Approximately 1,000 individuals of Orcutt’s brodiaea were observed, sometimes overlapping with populations of thread-leaf brodiaea as previously described.
Special-Status Wildlife Species
Species defined as “special-status wildlife species” in this report include endangered and threatened wildlife species recognized in the context of the California and federal Endangered Species Acts (Appendix C); Species of Special Concern assigned by CDFW to species whose population levels are declining, have limited ranges, and/or are vulnerable to extinction due to continuing threats; Fully Protected species protected by the CDFW and Watch List species candid ates for higher sensitivity statuses; and Birds of Conservation Concern provided by USFWS to migratory and non-migratory bird species that adhere to the 1988 amendment to the Fish and Wildlife Conservation Act that mandates USFWS to “identify species, subspecies, and populations of all migratory nongame birds that, without additional conservation actions, are likely to become candidates for listing under the Federal Endangered Species Act of 1973” (Appendix C).
Appendix D, Wildlife Species with a Moderate to High Potential to Occur, of Appendix C lists the special- status wildlife species known to occur within the U.S. Geological Survey (USGS) San Marcos 7.5-Minute quadrangle map and the eight-quadrangle maps surrounding the project site, including the Morro Hill, Bonsall, Pala, San Luis Rey, Valley Center, Encinitas, Rancho Santa Fe, and Escondido (CDFW 2021 ; USFWS 2021 a). Due to the presence of multiple sensitive vegetation communities and wetland habitats on predominantly undeveloped land, the project site has moderate value as habitat for these endangered, rare or threatened wildlife species. Based on a review of the potential species to occur within the region and the habitat conditions identified with the project site, seven special-status wildlife species have a moderate to high potential to occur.
The federally and state endangered least Bell ’s vireo ( Vireo bellii pusillus ) was observed during the field reconnaissance study moving into the vernal pool areas from the willow riparian habitat. Least Bell’s vireo was heard and observed numerous times. Special -status avian species that were also incidentally observed within the project area include the Cooper’s hawk (CDFW Watch List) and white- tailed kite (CDFW Fully Protected). The undeveloped sensitive upland and wetland habitats within the project area have the potential to support nesting and foraging opportunities for other rare and special- status avian species not incidentally observed during the initial survey due to seasonal limitations.
Focused surveys for coastal California gnatcatcher were negative (Appendix E of Appendix C). However, due to the presence of suitable habitat for coastal California gnatcatcher on the project site, pre-construction focused surveys are recommended, as noted in Section 3.3.7, Mitigation Measures.
Additionally, San Diego fairy shrimp ( Branchinecta sandiegonensis ) is a federally endangered invertebrate species with a high potential to occur within the San Diego Mesa Claypan vernal pools on
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the eastern portion of the project area. It should also be noted that the project area overlaps with USFWS designated critical habitat for the San Diego fairy shrimp. Therefore, there is a high potential for this species to occur within the project site.
3.3.1.6 Jurisdictional Aquatic Resources
The jurisdictional delineation was conducted by Dudek biologist Cody Schaaf on September 8, 2021, focusing on potential features within the on-site development footprint. Results of wetland delineation indicate that the project site supports 0.20 acre s of jurisdictional aquatic resources including
0.05 acres of non-wetland waters regulated by USACE and the Regional Water Quality Control Board (RWQCB), as well as 0.09 acres of streambed and 0.11 acres of associated riparian habitat regulated by CDFW (Table 3.3-3). Wetland Determination Forms were taken at sample points within the mapped freshwater emergent wetland in the center of the impact footprint, as well as along the drainage channel, in patches of tamarisk and other hydrophytic vegetation at various locations throughout the review area. None of the points were determined to meet all three parameters. Accordingly, no USACE wetlands are present in the review area. Because CDFW regulates from bank to bank, certain portions within the project footprint where the top of a channel bank extended beyond the ordinary high-water mark (OHWM) are subject to regulation by CDFW as streambed.
Table 3.3-3
Jurisdictional Aquatic Resource Summary
Regulating Agency Jurisdictional Resource Acres
USACE/RWQCB Non-wetland waters 0.05
Total USACE/RWQCB 0.05
CDFW Streambed 0.09
Riparian habitat – Disturbed wetland 0.11
Total CDFW 0.20
Notes:
USACE = U.S. Army Corp s of Engineers; RWQCB = Regional Water Quality Control Board; CDFW = California Department of Fish and Wildlife
The emergent wetland mapped within the project site is located upslope of the channel and associated disturbed wetland and as such, this area does not receive flows from the channel and is therefore not regulated by CDFW as associated riparian habitat. The project also supports 0. 12 acres that is dominated by giant reed and 0.58 acres that is dominated by tamarisk, both of which are considered highly invasive species. They outcompete native plant species that provide vital habitat for wildlife. As such, although these species are rated as wetland plants, they are not designated as CDFW riparian habitat per a pre-application meeting with CDFW. These two species are often the target of restoration projects that include their removal to mitigate for impacts to native wetland vegetation.
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3.3.1.7 Wildlife Corridors/Core Wildlife Areas
Wildlife corridors connect otherwise isolated pieces of habitat and allow movement or dispersal of plants and animals. Local wildlife corridors allow access to resources such as food, water, and shelter within the framework of their daily routine. Regional corridors provide these functions over a larger scale and link two or more large habitat areas, allowing the dispersal of organisms and the consequent mixing of genes between populations. A corridor is a specific route that is used for the movement and migration of species and may be different from a linkage in that it represents a smaller or narrower avenue for movement. A linkage is an area of land that supports or contributes to the long -term movement of animals and genetic exchange by providing live-in habitat that connects to other habitat areas. Many linkages occur as stepping-stone linkages that are made up of a fragmented archipelago arrangement of habitat over a linear distance.
Important corridors and linkages have been identified on a local and regional scale throughout the Draft North County MHCP (AMEC Earth & Environmental et al. 2003) and adopted City of San Marcos General Plan (City of San Marcos 2012). The planning objectiv es of most corridors and linkages in western San Diego County include establishing a connection between the northern and southern regional populations of the coastal California gnatcatcher, in addition to facilitating movement and connectivity of habitat for large mammals and riparian bird species.
The project site is not identified as a wildlife corridor in the City of San Marcos General Plan (City of San Marcos 2012). The project site is not identified as a preserve, nor are there preserve lands located within 2,000 feet of project site. The project site is not contiguous with any undeveloped land. Given the barrier posed by surrounding development, the site is not expected to serve as a regional wildlife corridor or substant ial habitat linkage that would be used by large mammals, riparian birds, or migratory birds.
Thus, given the project site location immediately adjacent to and surrounded by existing roadways and development within an urban setting, the project site is not considered to serve as a wildlife corridor or habitat linkage, either locally or regionally.
3.3.2 Methodology
3.3.2.1 Literature Review
To assess biological resources and potential constraints, Dudek reviewed available relevant literature and data on sensitive habitats and species distribution to determine those resources that have the potential for occurrence within the San Marcos USGS 7.5 -Minute Quadrangle Map and the 8-Quadrangle Maps surrounding the project site. Prior environmental documents prepared for the
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project provided information on biological resources and constraints previously identified. The review included the following:
• CDFW California Natural Diversity Database (CDFW 2021) including the Morro Hill, Bonsall, Pala, San Luis Rey, Valley Center, Encinitas, Rancho Santa Fe, and Escondido USGS Quadrangle Maps.
• California Native Plant Society’s Inventory of Rare and Endangered Plants (CNPS 2021) for the San Marcos and surrounding 7.5-minute USGS quadrangles. • USFWS Information for Planning and Consultation (IPaC) (USFWS 2021a) including USGS 7.5- minute San Marcos and surrounding 7.5-minute USGS quadrangles. • U.S. Department of Agriculture Natural Resources Conservation Service Web Soil Survey (USDA 2020a) was used to identify soil types occurring within the project site. • Google Earth (2021).
• USFWS National Wetlands Inventory (USFWS 2021b).
• USGS National Hydrography Dataset (USGS 2021a, 2021b). • San Diego County Bird Atlas (Unitt 2004).
• San Diego Natural History Museum’s Plant Atlas (SDNHM 2021). • Vegetation and Sensitive Resources/Impacts for the San Marcos Superior Ready Mix Parcel [map] (Helix Environmental Planning 2005).
3.3.2.2 Field Surveys
Field Reconnaissance
An initial due diligence survey was conducted by Dudek biologist Erin Bergman to identify the existing conditions and determine the potential biological constraints to the project. On April 15, 2021, and April 27, 2021, Dudek biologist Erin Bergman conducted vegetation mapping and a general biological reconnaissance of the project site. In addition, focused rare plant surveys were conducted in the spring and summer of 2021 by Dudek biologist Erin Bergman to determine the presence/absence of various special-status species. Watershed mapping for the vernal pools was conducted by habitat restoration specialist Scott McMillian. Cody Schaff conducted a jurisdictional delineation on September 8, 2021.
Focused surveys for coastal California gnatcatcher (Polioptila californica californica) were conducted in May 2023 by USFWS permitted biologist Erin Bergman (TE53771B -0). Updated focused surveys to document the change in presence and extent of any Brodiaea species observed in 2021 was conducted in June 2023. Table 3.3-4, Schedule of Surveys, lists the dates, conditions, and focus for each survey.
All focused surveys have been conducted to date, and the results are provided in this report.
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Table 3.3-4
Schedule of Surveys
Date Hours Focus Personnel Conditions
4/15/2021 0800-1700 Biological Reconnaissance
#1
EB 57°F–77°F; 0%–100% cloud
cover; 2–5 mph winds
4/27/2021 0800-1700 Biological Reconnaissance
#2
EB 57°F–77°F; 0%–100% cloud
cover; 2–5 mph winds
5/24/2021 0830-1630 Special-Status Plant
Survey #1
EB 64°F–78°F; 0%–40% cloud cover;
0-4 mph winds
6/5/2021 Not recorded Vernal Pool Watershed
Mapping
SM Not recorded
8/30/2021 0900-1300 Special-Status Plant
Survey #2
EB 65°F–82°F; 20%–80% cloud
cover; 0-3 mph winds
9/8/2021 0920-1500 Jurisdictional Delineation CS 73°F–82°F; 0%–0% cloud cover; 0–4 mph winds
5/10/2023 0626–1201 CAGN Protocol Survey
No. 1
EB 63°F–67°F; 100% cloud cover;
0–3 mph wind
5/17/2023 0754 - 1215 CAGN Protocol Survey
No. 2
EB 58°F–65°F; 40%–50% cloud
cover; 0-4 mph wind
5/24/2023 0730 –1200 CAGN Protocol Survey
No. 3
EB 59°F–69°F; 50%–100% cloud
cover; 0–5 mph wind
6/8/2023 Not recorded Focused Brodiaea Survey SM Not recorded Notes:
mph = miles per hour
Personnel: EB = Erin Bergman, SM = Scott McMillian, CS= Cody Schaaf All plant species encountered during the surveys were recorded. Latin and common names for plant species with a CRPR follow the California Native Plant Society’s On-Line Inventory of Rare, Threatened, and Endangered Plants of California (Appendix C). For plant species without a CRPR, Latin names follow the Jepson Interchange List of Currently Accepted Names of Native and Naturalized Plants of California (Jepson Flora Project 2020) and common names follow the U.S. Department of Agriculture Natural Resources Conservation Service PLANTS Database (USDA 2020b).
All wildlife species observed or detected during the surveys were recorded. Binoculars (10 × 50 magnification) were used to aid in the identification of wildlife. Latin and common names of animals follow Crother (2012) for reptiles and amphibians, American Ornithological Society (AOS 2020) for birds, Wilson and Reeder (2005) for mammals, and North American Butterfly Association (NABA 2016) or San Diego Natural History Museum (SDNHM 2002) for butterflies. In addition to species actually detected during the s urveys, expected wildlife use of the site was determined by known habitat preferences of local species and knowledge of their relative distributions in the area.
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Vegetation Community and Land Cover Mapping
Dudek conducted vegetation mapping to characterize natural vegetation communities, including habitats for special-status species, within the project site. The vegetation community and land cover mapping follow the Draft Vegetation Communities of San Diego County (Oberbauer et al. 2008), which is based on the Preliminary Descriptions of the Terrestrial Natural Communities of California (Holland 1986). Vegetation mapping was conducted within the project site on April 15, 2021, and April 27, 2021 in conjunction with the initial reconnaissance-level surveys for sensitive resources.
Vegetation communities and land covers within the survey area were mapped in the field with Collector, digitized using ArcGIS, and a geographic information system (GIS) coverage was created.
Once in ArcGIS, the acreage of each vegetation community and land cover present within the survey area was determined.
Botanical Surveys
Dudek botanist Erin Bergman conducted a spring focused special -status plant survey on May 24, 2021, and a summer focused special -status plant survey on August 30, 2021. The survey date, biologist, and weather conditions are provided in Table 3.3-4. Field survey methods and mapping of rare plants conformed to California Native Plant Society ’s Botanical Survey Guidelines (CNPS 2001), Protocols for Surveying and Evaluating Impacts to Special Status Native Populations and Natural Communities (CDFW 2018), and Ge neral Rare Plant Survey Guidelines (Cypher 2002). The surveys consisted of one survey pass in May and one survey pass in August that provided 100% coverage of the project site.
Before conducting the late season focused rare plant survey, on August 16, 2021, Dudek botanist Erin Bergman conducted botanical reference population checks on the project site to ensure the focal special-status plant species were in bloom and identifiable. Reference checks were conducted for graceful tarplant ( Holocarpha virgata ssp. elongata), as it blooms from May through November.
Populations of this species were observed throughout the project Site during the botanical reference check. Botanical refere nce checks for thread -leaved brodiaea ( Brodiaea filifolia ), small -flowered morning glory (Convolvulus simulans), Orcutt’s brodiaea ( Brodiaea orcuttii), San Diego button -celery (Eryngium aristulatum var. parishii) and spreading navarretia (Navarretia fossalis) were not conducted, as they bloom during the spring and were mostly observed during the initial biological reconnaissance.
A list of all plant species observed on the project site during surveys is presented in Appendix A, Plant Compendium, of Appendix C.
Dudek botanist and habitat restoration ecologist Scott McMillan conducted an updated plant survey of the project survey area on June 8, 2023. A meandering walking survey was conducted across the entire site to document any changes in the presence and exten t of Brodiaea species populations documented in 2021.
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Wildlife Surveys
Least Bell’s vireo was detected during surveys moving into the vernal pool areas from willow riparian, and least Bell’s vireo were heard and observed numerous times indicating the likely presence of more than one pair. Therefore, it is assumed that this species u ses riparian habitat within and adjacent to the project site. Focused surveys for coastal California gnatcatcher were conducted by a USFWS permitted biologist (Erin Bergman; TE53771B -0). All suitable habitat within the project site was covered on fo ot during each survey visit for 100% visual and audible coverage. Survey visits were conducted at minimum 1 -week intervals (i.e., 7 -day intervals) and were performed in conformance with the currently accepted protocol of the USFWS Coastal California Gnatcatcher ( Polioptila californica californica) Presence/Absence Survey Protocol (USFWS 1997).
A tape of recorded gnatcatcher vocalizations was played every approximately 25 feet to induce responses from potentially present gnatcatchers. Tape -playback would have been terminated immediately upon detection of any gnatcatchers to minimize the potential for harassment. A 200-scale (1 inch = 200 feet) aerial photograph of the project site and a vegetation map were used to identify suitable habitats and map any gnatcatchers detected. Binoculars were used to aid in detecting and identifying bird species. We ather conditions, time of day, and season were appropriate for the detection of gnatcatchers.
San Diego fairy shrimp ( Branchinecta sandiegonensis), a federally endangered species, is known to occur within the immediate vicinity of the project and has a high potential to occur within the on -site vernal pools. Since the project will not result in impacts to the vernal pools, focused surveys to document presence/absence of this species are not necessary at this time. A list of all wildlife species observed on the project site during surveys is presented in Appendix B , Wildlife Compendium , of Appendix C.
Aquatic Resource Delineation
A jurisdictional aquatic resource delineation was conducted within the potential development area only to determine the extent of resources that may be under the jurisdiction of USACE pursuant to Section 404 of the federal Clean Water Act (CWA), RWQCB purs uant to CWA Section 401 and the Porter–Cologne Act, and the CDFW pursuant to Sections 1600–1603 of the California Fish and Game Code (CFGC).
The delineation was conducted in accordance with the methods prescribed in the 1987 Corps of Engineers Wetland Delineation Manual (USACE 1987), the 2008 Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Arid West Region (Version 2.0) (USACE 2008a), and the Field Guide to the Identification of the Ordinary High Water Mark (OHWM) in the Arid West Region of the Western United States: A Delineation Manual (USACE 2008b). During the jurisdictional delineation, the site was walked and evalu ated for evidence of an OHWM, surface water, saturation, wetland
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vegetation, and nexus to a traditional navigable water of the United States. The extent of any identified jurisdictional areas was determined by mapping the areas with similar vegetation and topography to the sampled locations.
Waters of the state regulated by the RWQCB were mapped in accordance with the State Wetland Definition and Procedures for Discharges of Dredged or Fill Material to Waters of the State, adopted April 2, 2019 ( Appendix C). As described in these procedures, wetland waters of the state will be mapped based on the procedures in USACE’s 1987 Corps of Engineers Wetlands Delineation Manual (USACE 1987) and its 2008 Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Arid West Region (Version 2 .0) (USACE 2008a). Non -wetland waters were mapped at the OHWM based on the procedures used to delineate USACE non-wetland waters (USACE 2008b).
CDFW jurisdictional areas were mapped to include the bank of the stream/channel and outer dripline of adjacent riparian vegetation, as set forth under CFGC Section 1602. Streambeds under the jurisdiction of CDFW were delineated using the Cowardin method of waters classification, which defines waters boundaries by a single parameter (i.e., hydric soils, hydrophytic vegetation, or hydrology) (Cowardin et al. 1979).
Features that convey or hold water are regulated by multiple agencies. Federal, state, and local agencies have different definitions and terminology for these types of features. Water -dependent resources regulated by USACE, RWQCB, CDFW, and the County of San Diego are collectively referred to as “jurisdictional aquatic resources” herein. Terminology used in this document to distinguish each jurisdictional aquatic resource according to the agency that regulates the resource is as follows: USACE and RWQCB Wetlands” and “non-wetland waters” and CDFW “riparian areas” and “streambeds.”
3.3.2.3 Survey Limitations
The reconnaissance survey, jurisdictional delineation, focused rare plant surveys, protocol coastal California gnatcatcher surveys and vegetation mapping were done during the daylight hours under weather conditions that allowed for quality biological observations (e.g., surveys were not conducted during rain). Because surveys were conducted during the day, the likelihood of detecting nocturnal and crepuscular species, such as many mammal species, was relatively low. In addition, any fall migratory birds that may use habitats in the project site and pass through the region would not have been observed due to the period surveys were conducted. The surveys were favorable for spring and summer blooming flora because surveys were conducted in late spring, and therefore many flowering plant species were in bloom. However, the Southern California region is experiencing a drought and surveys were delayed allowing additional blooming period for species that were blooming later in the season than normal. Additional surveys after a strong rainy season were conducted in 2023 to account for this limitation.
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3.3.3 Regulatory Setting
Federal
Federal Endangered Species Act
Administered by the USFWS, the federal Endangered Species Act (FESA) of 1973 provides the legal framework for the listing and protection of species (and their habitats) that are identified as being endangered or threatened with extinction. Under FESA, “take” of listed animal and plant species in areas under federal jurisdiction is prohibited without obtaining a federal permit . FESA Section 9(a) defines take as “to harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect, or attempt to engage in any such conduct.” “Harm” and “harass” are further defined in federal regulations and case law to include actions that adversely impair or disrupt a listed species’ behavioral patterns. Under FESA, USFWS may issue incidental take statements, which authorize the take of listed wildlife species provided such take does not jeopardize the continued existence of the species.
FESA Sections 7 and 4(d) regulate actions that could jeopardize endangered or threatened species.
Section 7, administered by the USFWS, describes a process of Federal interagency consultation for use when Federal actions may adversely affect listed species. A S ection 7 Consultation (formal or informal) with USFWS is required when there is a nexus between a listed species’ use of a site and a project is requesting a federal action, including funding. If the action may affect listed species, a biological assessment is required for any major construction activity. The USFWS determines, through the biological assessment or other review, whether the action is likely to adversely affect a listed species and thereby require formal consultation. At the conclusion of formal consultation, the USFWS will prepare a Biological Opinion. The Biological Opinion will state whether the Federal agency has insured that its action is not likely to jeopardize the continued existence of a listed species and/or result in the destruction or adverse modification of critical habitat. If avoidance cannot be achieved, incidental take can be authorized via the Biological Opinion, issued by USFWS, for non-marine related listed species issues. A Section 7 Consultation could be required if impacts to a federally listed species would occur and there is requested federal action.
If a project could directly or indirectly impact federally listed species and/or their critical habitat, and there is no federal action/nexus (e.g., permit, funding, ownership), FESA requires the project proponent to consult with the USFWS under Section 10. A consultation under FESA Section 10 requires submittal of an Incidental Take Permit application and a Habitat Conservation Plan to USFWS for evaluation of project impacts. If the USFWS determines the project would have a “low effect” on listed, proposed, or candidate species and their habitats, and the project would have minor effects on other environmental resources, the USFWS would complete the consultation process and issue an Incidental Take Permit.
If a project is determined by USFWS to have a “moderate or high effect” on listed, proposed, or candidate species and their habitats, the USFWS would require preparation of National Environmental
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Policy Act (NEPA) analysis prior to issuance of an Incidental Take Permit . The NEPA analysis would include additional evaluation of the project impacts in the form of an Environmental Assessment or an Environmental Impact Statement. A Section 10 Consultation could be required if impacts to a federally listed species would occur.
Identified by the USFWS, critical habitat is defined as areas of land that are considered necessary for endangered or threatened species to recover. The ultimate goal is to restore healthy populations of listed species within their native habitat, so they can be removed from the list of threatened or endangered species. Once an area is designated as critical habitat pursuant to the FESA, all federal agencies must consult with the USFWS to ensure that any action they authorize, fund, or carry out is not likely to result in destruction or adverse modification of the critical habitat.
Clean Water Act
The CWA is intended to restore and maintain the quality and biological integrity of the nation’s waters.
Section 402 of the CWA prohibits the discharge of pollutants to “waters of the United States” from any point source unless the discharge is in compliance with a National Pollutant Discharge Elimination System Permit. The CWA, Section 402, require s a National Pollutant Discharge Elimination System Permit for the discharge of stormwater from municipal separate storm sewer systems serving urban areas with a population greater than 100,000, construction sites that disturb 1 acre or more, and industrial facilities. The RWQCB administers these permits with oversight provided by the State Water Resources Control Board and U.S. Environmental Protection Agency Region IX.
Section 404 of the CWA authorizes the Secretary of the Army, acting through the USACE, to issue permits regulating the discharge of dredged or fill materials into the “navigable waters at specified disposal sites.” CWA Section 502 further defines “navigable waters” as “waters of the United States, including territorial seas.” Waters of the United States are broadly defined in the Code of Federal Regulations (CFR), Title 33, Section 328.3, Subdivision (a), to include navigable waters; perennial and intermittent streams, lakes, rivers, and ponds; and wetlands, marshes, and wet meadows.
The limits of the USACE’s CWA Section 404 jurisdiction in non-tidal waters are defined by the OHWM, unless adjacent wetlands are present. The OHWM is a line on the shore or edge of a channel established by the fluctuations of water and indicated by physical characteristics such as a clear, natural line impressed upon the bank, shelving, changes in the character of soil, destruction of vegetation, or presence of debris (33 CFR 328.3). As a result, waters are recognized in the field by the presence of a defin ed watercourse with appropriate physical and topographic features. If wetlands occur within or adjacent to waters of the United States, the lateral limits of the USACE’s jurisdiction extends beyond the OHWM to the outer edge of the wetland.
Section 401 of the CWA requires that an applicant for a federal license or permit to discharge into navigable waters provide the federal agency with a water quality certification declaring that the
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discharge would comply with water quality standard requirements of the CWA. USACE is prohibited from issuing a CWA permit until the applicant receives a CWA, Section 401, water quality certification or waiver from the RWQCB.
Migratory Bird Treaty Act
The Migratory Bird Treaty Act (MBTA) was originally passed in 1918 as four bilateral treaties, or conventions, for the protection of a shared migratory bird resource. The primary motivation for the international negotiations was to stop the “indiscriminate slaughter” of migratory birds by market hunters and others. Each of the treaties protects selected species of birds and provides for closed and open seasons for hunting game birds. The MBTA protects more than 800 species of birds and prohibits the take of any migratory bird or any part, nest, or eggs of any such bird. Under the MBTA, “take” is defined as pursuing, hunting, shooting, capturing, collecting, or killing, or attempting to do so (16 USC 703 et seq. ). Additionally, Executive Order 13186, Responsibilities of Federal Agencies to Protect Migratory Birds, requires that any project with federal involvement address impacts of federal actions on migratory birds with the purpose of promoting conservation of migratory bird populations (66 FR 3853–3856). Th e executive order requires federal agencies to work with USFWS to develop a memorandum of understanding. USFWS reviews actions that might affect these species.
Two species of eagles that are native to the United States, bald eagle ( Haliaeetus leucocephalus ) and golden eagle ( Aquila chrysaetos ), were granted additional protection within the United States under the Bald and Golden Eagle Protection Act (16 USC 668 –668d) to prevent the species from becoming extinct.
State
California Environmental Quality Act
Primary environmental legislation in California is found in CEQA and its implementing guidelines (State CEQA Guidelines), which require that projects with potential adverse effects (i.e., impacts) on the environment undergo environmental review. Adverse environmental impacts are typically mitigated as a result of the environmental review process in accordance with existing laws and regulations.
California Endangered Species Act
CDFW administers the CESA (CFGC Section 2050 et seq.), which prohibits the take of plant and animal species designated by the Fish and Game Commission as endangered or threatened in California.
Under the CESA, Section 86, take is defined as “hunt, pursue, catch, capture, or kill, or atte mpt to hunt, pursue, catch, capture, or kill.” CESA Section 2053, stipulates that state agencies may not approve projects that would “jeopardize the continued existence of any endangered species or threatened species or resu lt in the destruction or adverse modification of habitat essential to the
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continued existence of those species, if there are reasonable and prudent alternatives available consistent with conserving the species or its habitat which would prevent jeopardy.” CESA Sections 2080 through 2085 address the taking of threatened, endangered, or candidate species by stating, “No person shall import into this state, export out of this state, or take, possess, purchase, or sell within this state, any species, or any part or product thereof, that the Commission determines to be an endangered species or a threatened species, or attempt any of those acts, except as otherwise provided in this chapter, the Native Plant Protection Act (CFGC Sections 1900–1913), or the California Desert Native Plants Act (Food and Agricultural Code, Section 80001).” California Fish and Game Code
The California Fish and Game Code (CFGC) provides specific protection and listing for several types of biological resources. CFGC Section 1600 requires a Streambed Alteration Agreement for any activity that would alter the flow, change, or use any material from the bed, channel, or bank of any perennial, intermittent, or ephemeral river, stream, and/or lake. Typical activities that require a Streambed Alteration Agreement include excavation or fill placed within a channel, vegetation clearing, structures for diversion of water, installation of cu lverts and bridge supports, cofferdams for construction dewatering, and bank reinforcement. Notification is required prior to any such activities.
If the project could result in adverse impacts to a state -listed species that is not also federally listed, CFGC Section 2081(b) provides a mechanism for CDFW to permit, on a project -specific basis, incidental take of species listed under CESA. Preparation and submittal of an Incidental Take Permit application with CDFW by the project proponent is required. The application must include project details, potential project impacts, an analysis of “jeopardy” for the continued existence of the impacted species, and species -specific mitigation and avoidance measures that would fully mitigate for the project impacts.
Pursuant to CFGC Section 3503, it is unlawful to take, possess, or needlessly destroy the nest or eggs of any bird, except as otherwise provided by this code or any regulation made pursuant thereto.
Raptors and owls and their active nests are protected by CFGC Section 3503.5, which states that it is unlawful to take, possess, or destroy any birds of prey or to take, possess, or destroy the nest or eggs of any such bird unless authorized by the CDFW. CFGC Section 3513 states that it is unlawful to take or possess any migratory non-game bird as designated in the MBTA. These regulations could require that construction activities (particularly vegetation removal or construction near nests) be reduced or eliminated during critical phases of the nesting cycle unle ss surveys by a qualified biologist demonstrate that nests, eggs, or nesting birds will not be disturbed, subject to approval by CDFW and/or USFWS.
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Porter-Cologne Water Quality Control Act
This statute regulates surface waters and wetlands within the State and is governed by the RWQCB.
Features that support aquatic resources (i.e., hydrophytic vegetation, hydric soils, and wetland hydrology), but are isolated (i.e., lack downstream connectiv ity to waters of the U nited States) could be subject to regulation pursuant to the State Porter -Cologne Water Quality Control Act (Porter - Cologne). Impacts to isolated wetlands and/or waters of the state require a Waste Discharge Requirement Permit from the RWQCB.
Natural Communities Conservation Planning Act
The Natural Communities Conservation Planning (NCCP) program is a cooperative effort to protect habitats and species. It began under the state’s NCCP Act of 1991, legislation broader in its orientation and objectives than the CESA or FESA. These laws are designed to identify and protect individual species that have already declined significantly in number. The California NCCP Act of 1991 (Section 2835) allows the CDFW to authorize take of species covered by plans in agreement with NCCP guidelines. An NCCP, initiated by the State of California, focuses on conserving coastal sage scrub, and in concert with the USFWS and the FESA, is intended to avoid the need for future federal and state listing of coastal sage scrub-dependent species. The NCCP Act of 1991 and the associated Southern California Coastal Sage Scrub NCCP Process Guidelines (1993), Southern California Coastal Sage Scrub NCCP Conservation Guidelines (1993), and NCCP General Process Guidelines (1998) have been superseded by the NCCP Act of 2003.
The primary objective of the NCCP program is to conserve natural communities at the ecosystem level while accommodating compatible land use. The program seeks to anticipate and prevent the controversies and gridlock caused by species’ listings by focusing on the long-term stability of wildlife and plant communities and including key interests in the process.
This voluntary program allows the state to enter into planning agreements with landowners, local governments, and other interested parties to prepare plans that identify the most important areas for a threatened or endangered species, and the areas that may be less important. These NCCP plans may become the basis for a state permit to take threatened and endangered species in exchange for conserving their habitat. The CDFW and USFWS worked to combine the NCCP with the federal Habitat Conservation Plan process to provide take permits for state and federal ly listed species. Under the NCCP, local governments, such as the County of San Diego , can take the lead in developing these NCCP plans and become the recipients of state and federal take permits.
Multiple Habitat Conservation Program
The Multiple Habitat Conservation Program ( MHCP) spans northwestern San Diego County and has goals of providing protection for over 80 special -status species and approximately 19,000 acres of
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proposed conservation land ( AMEC Earth & Environmental et al. 2003 ). The City of San Marcos and six additional city jurisdictions (Carlsbad, Encinitas, Escondido, Oceanside, Solana Beach, and Vista) make up the MHCP Plan area. It is a comprehensive, long -term habitat conservation plan that addresses the needs of multiple species by identifying key areas for preservation as open space in order to link core biological areas into a regional wildlife preserve. The MHCP is one of several large multiple jurisdict ional habitat planning efforts in San Diego County, each of which constitutes a subregional plan under the NCCP Act of 1991. The MHCP includes incorporated cities in northwestern San Diego County that will implement their respective portions of the MHCP through citywide “subarea” plans, which describe the specific implementing mechanisms each city will institute for the MHCP.
The City of San Marcos Subarea Plan has not been finalized or implemented, and the City is no longer an active participant in the NCCP program and the subregional MHCP conservation planning effort.
However, it is the City ’s policy to comply with the conservation policies identified in the Draft San Marcos Subarea Plan, including an assessment of designated Biological Core Linkage Areas or MHCP Focused Planning Areas in the context of the project. In addition, the project will be evaluated to ensure consistency with CEQA.
The City of San Marcos Municipal Code was reviewed and contains additional environmental standards for the City environmental review process in Title 18, which defines how the City will define environmental protection and the steps thereafter. The site is designed as Light Industrial in the General Plan (City of San Marcos 2012).
Local
City of San Marcos General Plan
The Conservation and Open Space Element of the City ’s General Plan contains several policies pertaining to the protection of biological resources (City of San Marcos 2012). The following goals and policies apply to the project:
• Goal COS -1: Identify, protect, and enhance significant ecological and biological resources within San Marcos and its adaptive Sphere of Influence. o Policy COS-1.1: Support the protection of biological resources through the establishment, restoration, and conservation of high-quality habitat areas. o Policy COS-1.2: Ensure that new development, including Capital Improvement Projects, maintain the biotic habitat value of riparian areas, oak woodlands, habitat linkages, and other sensitive biological habitats.
o Policy COS-1.3: Continue to work with other federal, State, regional, and local agencies to implement SANDAG’s MHCP.
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• Goal COS -2: The City is committed to conserving, protecting, and maintaining open space, agricultural, and limited resources for future generations. By working with property owners, local organizations, and state and federal agencies, the City can limit the conversio n of resource lands to urban uses.
o Policy COS -2.1: Provide and protect open space areas throughout the City for its recreational, agricultural, safety, and environmental value. o Policy COS-2.2: Limit, to the extent feasible, the conversion of open space to urban uses and place a high priority on acquiring and preserving open space lands for recreation, habitat protection and enhancement, flood hazard management, water and agricultural resources protection, and overall community benefit.
o Policy COS-2.6: Preserve healthy mature trees where feasible; where removal is necessary, trees shall be replaced at a ratio of 1:1.
• Goal COS -3: Protect natural topography to preserve and enhance the natural beauty of San Marcos.
o Policy COS -3.3: Continue to work with new development and redevelopment project applicants in designing land use plans that respect the topography, landforms, view corridors, wildlife corridors, and open space that exists. o Policy COS-3.4: Evaluate potential impacts to visual and aesthetics resources, including the potential to create new light sources, while still maintaining and being sensitive to rural lighting standards.
• Goal COS-8: Focus watershed protection, surface and groundwater quality management on sources and practices that the City has the ability to affect. o Policy COS -8.4: Require new development and redevelopment to protect the quality of water bodies and natural drainage systems through site design, source controls, storm water treatment, runoff reduction measures, Best Management Practices (BMPs), low impact development hydromodification strategies consistent with the current San Diego Regional Water Quality Control Board Municipal Stormwater National Pollutant Discharge Elimination System Permit, and all future municipal stormwater permits.
The project’s consistency with applicable General Plan goals and policies is discussed in Section 3.10, Land Use and Planning. As shown in Section 3.10.4, the project is consistent with the applicable goals and policies related to biological resources.
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3.3.4 Thresholds of Significance
The significance criteria used to evaluate the project impacts to biological resources are based on Appendix G of the CEQA Guidelines. According to Appendix G of the CEQA Guidelines, a significant impact related to biological resources would occur if the project would:
• Threshold #1: Have a substantial adverse effect, either directly or through habitat modifications, on any species identified as a candidate, sensitive, or special status species in local or regional plans, policies, or regulations, or by the California Department of Fis h and Wildlife or U.S. Fish and Wildlife Service.
• Threshold #2: Have a substantial adverse effect on any riparian habitat or other sensitive natural community identified in local or regional plans, policies, regulations or by the California Department of Fish and Wildlife or U.S. Fish and Wildlife Service. • Threshold #3: Have a substantial adverse effect on state or federally protected wetlands (including, but not limited to, marsh, vernal pool, coastal, etc.) through direct removal, filling, hydrological interruption, or other means.
• Threshold #4: Interfere substantially with the movement of any native resident or migratory fish or wildlife species or with established native resident or migratory wildlife corridors, or impede the use of native wildlife nursery sites.
• Threshold #5: Conflict with any local policies or ordinances protecting biological resources, such as a tree preservation policy or ordinance.
• Threshold #6: Conflict with the provisions of an adopted Habitat Conservation Plan, Natural Community Conservation Plan, or other approved local, regional, or state habitat conservation plan.
3.3.5 Project Impact Analysis
This section defines the types of impacts that would occur due to project implementation, including direct, permanent impacts; direct, temporary impacts; and indirect impacts.
Direct Impacts
Direct, permanent impacts refer to the absolute and permanent physical loss of a biological resource due to clearing, grading, and construction of a project. Direct, permanent impacts are analyzed in four ways: (1) permanent loss of vegetation communities and land covers and general wildlife and their habitat; (2) permanent loss of or harm to individuals of special -status plant and wildlife species; (3) permanent loss of suitable habitat for special -status species; and/or (4) permanent loss of wildlife movement and habitat connectivity.
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Direct, temporary impacts refer to a temporal loss of vegetation communities and land covers resulting from vegetation and land cover clearing and grading associated with implementation of a project. The main criterion for direct, temporary impacts is that impacts occur for a short period of time and are reversible.
Indirect Impacts
Indirect impacts are reasonably foreseeable effects caused by a project ’s implementation on remaining or adjacent biological resources outside of the direct disturbance zone that may occur during grading activities (i.e., short -term construction-related indirect impacts) or later in time as a result of a project (i.e., long -term, or operational, indirect impacts). Short -term indirect impacts can include dust, human activity, pollutants, erosion, and noise that extend beyond the identified construction area. Long-term indirect impacts can include changes to hydrology, introduction of invasive species, dust, and noise that are operations related or occur over the long term. In most cases, indirect effects are not quantified, but in some cases, quantification m ight be included, such as using a noise contour to quantify indirect impacts to nesting birds.
For each of the following impact sections, direct and indirect impacts for biological resources are identified and a significance determination is made for each impact. For each significant impact, mitigation measures that would reduce the impact to less than significant are proposed.
Threshold #1: Would the project have a substantial adverse effect, either directly or through habitat modifications, on any species identified as a candidate, sensitive, or special status species in local or regional plans, policies, or regulations, or by the California Department of Fish and Wildlife or U.S. Fish and Wildlife Service?
Special status plant and animal species on the project site could be impacted as a result of project implementation (Impact BIO-1). These species are discussed further below.
Special-Status Plants
Focused rare plant species surveys were conducted during spring and summer blooming periods in 2021 to determine the full extent of flora within the project area. An updated survey focusing on the potential change in Brodiaea populations was conducted in June 2023. Four special -status plant species were identified within the central and eastern portions of the project site within the wildflower fields, valley needlegrass grassland, and vernal pool habitats. All special -status plant populations as well as all vernal pools and associated watersheds will be avoided. Therefore, there are no direct impacts to special-status plant species.
Indirect impacts to special -status plant species would be limited to short -term construction impacts related to erosion, runoff, and dust. However, all project ground-disturbing activities would be subject
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to the typical restrictions (e.g., best management practices [BMPs]) and requirements that address erosion and runoff, including those of the National Pollutant Discharge Elimination System permit program and preparation of a Stormwater Pollution Preventio n Plan, including consistency with the Construction General Permit Order 2009 -009-DWQ. With implementation of these BMPs and permit conditions, potential indirect impacts to special-status plant species would be less than significant. In addition, implementation of Mitigation Measures (MM-)BIO-3 would ensure that any landscaping on site would prevent the introduction and spread of invasive plant species on the project site during construction and operations. Implementation of MM -BIO-5 would ensure that all construction personnel are aware of the sensitive plant species and their habitat.
Special-Status Wildlife Species
The undeveloped sensitive upland and wetland habitats within the project site have the potential to support least Bell’s vireo. This species was observed foraging on site and in off-site habitat. Although suitable coastal sage scrub habitat capable of supporting the coastal California gnatcatcher occurs throughout the project site, this species was not observed during multiple site visits conducted by a USFWS permitted coastal California gnatcatcher biologist for focused rare plant surveys and the initial biological reconnaissance. The project would result in the direct loss of 1.10 acres of wetland habitat that could be used by least Bell’s vireo as well as 0.89 acres of habitat that could be used by coastal California gnatcatcher. Direct impacts to these species would be mitigated through the implementation of MM-BIO-1 and MM-BIO-2 which provides for the preservation of 8.077.85 acres of high value habitat.
To further reduce potential direct impacts on coastal California gnatcatcher and least Bell ’s vireo during initial clearing/grubbing the project will implement MM-BIO-4 to MM-BIO-13, which includes temporary construction fencing. Environmental awareness training, breeding season avoidance, best management practices for construction and nesting bird surveys and avoidance measures.
Indirect effects to special -status wildlife species during project construction may include the generation of fugitive dust, changes in hydrology resulting from construction, including sedimentation and erosion, the release of chemical pollutants, and increased human presence. As noted above under indirect effects to vegetation, the potential indirect impacts from construction dust, erosion/sedimentation, and the release of chemical pollutants would be avoided and minimized through the implementation of ind ustry standard construction -related BMPs, including consistency with the Construction General Permit Order 2009 -009-DWQ, which would reduce these potential effects on special -status wildlife species to a level that is less than significant. Although increa sed human presence during construction may result in avoidance and/or behavioral modification by wildlife in the area, this effect would be short-term and is considered less than significant.
Noise generated during construction has the potential to indirectly impact adjacent special -status wildlife species by disrupting their normal activities, particularly breeding and nesting activities
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associated with special-status bird species. Special-status bird species, including federal - and state- listed species and species protected under protected under the MBTA and CFGC Sections 3503–3513 and Sections 3800–3801, may occur in habitats adjacent to the project area. Nesting birds can be affected by short -term construction -related noise, resulting in decreased reproductive success or abandonment of an area as nesting habitat. Breeding passerine and raptor species likely u se the various habitats on site for nest construction and foraging. Indirect impacts from construction-related noise may occur to breeding birds if construction occurs during the breeding season (i.e., February 15 through August 31). Potential impacts, including noise, lighting, incre ased human presence and vehicle traffic within the site could affect nesting birds. Pre -construction nesting bird surveys during the breeding season to avoid impacts to nesting birds in accordance with the MBTA and CFGC are a condition of project approval.
The proposed development of the site has the potential to result in significant impacts to special status plant and animal species (Impact BIO-1). However, implementation of mitigation measures MM-BIO-3 through MM-BIO-13 would ensure that potential i mpacts to special status species and their habitat are minimized and/or are reduced to below significant. Mitigation measures are outlined in detail in Section 3.3.7. With the implementation of proposed mitigation measures , impacts to special status plant and wildlife species would be less than significant with mitigation incorporated.
Threshold #2: Would the project have a substantial adverse effect on any riparian habitat or other sensitive natural community identified in local or regional plans, policies, regulations or by the California Department of Fish and Wildlife or U.S. Fish and Wildlife Service? The project would result in a potentially significant impact to sensitive natural communities (Impact BIO-2). The project would result in direct impacts to sensitive vegetation communities on-site. Sensitive natural communities on the project site that could be impacted are summarized below in Table 3.3-5.
Table 3.3-5
Direct Impacts to Vegetation Communities and Land Cover Types Vegetation
Community/
Land Cover
On-Site
Acreage
Direct Impact (acres)
Mitigation
Ratio
Required
Mitigation
(acres)
On-Site
Preservation
(acres) On-Site
Off-
Site Total
Group A – Wetland Communities
Arundo-
Dominated
Riparian
0.11 0.11 0.01 0.12 N/A 0 0
Disturbed
Wetland
0.11 0.11 0 0.11 3:1 0.33 0
Emergent
Wetland
0.59 0.29 0 0.29 3:1 0.86 0.30
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Table 3.3-5
Direct Impacts to Vegetation Communities and Land Cover Types Vegetation
Community/
Land Cover
On-Site
Acreage
Direct Impact (acres)
Mitigation
Ratio
Required
Mitigation
(acres)
On-Site
Preservation
(acres) On-Site
Off-
Site Total
San Diego
Mesa Claypan
Vernal Pool
0.43 0 0 0 3:1 0 0.43
Southern
Willow Scrub
0.03 0.03 0 0.03 3:1 0.09 0
Tamarisk Scrub 0.58 0.56 0 0.56 N/A 0 0.02
Subtotal Group
A – Wetlands
Communities
1.84 1.09 0.01 1.10 — 1.28 0.756
Group B – Rare Uplands
Valley
Needlegrass
Grassland
3.633.51 0 0 0 2:1 0 3.633.51
Wildflower Field 1.901.85 0 0 0 2:1 0 1.901.85
Subtotal Group
B. Rare
Uplands
5.535.36 0 0 0 — 0 5.535.36
Group C – Coastal Sage Scrub
Diegan Coastal
Sage Scrub
1.080.96 0.210.15 0.01 0.220.16 1:1 0.220.16 0.930.81
Diegan Coastal
Sage Scrub—
Baccharis-
Dominated
1.481.39 0.630.54 0.04 0.670.58 1:1 0.660.58 0.890.85
Subtotal Group
C – Coastal
Sage Scrub
2.562.35 0.840.69 0.05 0.890.74 — 0.880.74 1.821.67
Group D – Annual Grasslands
Non-Native
Grassland—
Broadleaf-
Dominated
0.07 0 0 0 0.5:1 0 0.07
Subtotal Group
D – Annual
Grasslands
0.07 0 0 0 — 0 0.07
Group F – Other Lands
Disturbed
Habitat
0.610.59 0.610.59 0.22 0.8381 N/A 0 0
Eucalyptus
Woodland
0.25 0.25 0 0.25 N/A 0 0
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Table 3.3-5
Direct Impacts to Vegetation Communities and Land Cover Types Vegetation
Community/
Land Cover
On-Site
Acreage
Direct Impact (acres)
Mitigation
Ratio
Required
Mitigation
(acres)
On-Site
Preservation
(acres) On-Site
Off-
Site Total
Subtotal Group
F – Other
Lands
0.860.84 0.860.84 0.22 1.081.06 — 0 0
Total* 10.8610.46 2.792.61 0.28 3.072.89 — 2.16 8.077.85 Note:
* Numbers may not sum due to rounding
Source: Appendix C
Of the approximately 10.8610.46 acres within the project, site, approximately 2.792.61 acres will be permanently impacted. Specifically, the western portion of the parcel will be impacted by proposed development, resulting in permanent impacts to 1.09 acres of wetland communities, 0.840.69 acres of coastal sage scrub and 1.080.84 acres of “other lands.” Off-site improvements along the frontage road would result in 0.28 acres of impact, of which 0.01 is arundo and 0.05 consists of coastal sage scrub. Total i mpacts to wetland communities i nclude 0.12 acres of Arundo-dominated riparian and
0.56 acres of tamarisk scrub. Although these species are categorized as wetland plant species they are highly invasive and are often the target of restoration projects that include their removal to mitigate for impacts to native wetland vegetation, as these species outcompete native habitats that provide vital habitat for wildlife. Therefore, mitigation is not proposed for impacts to these two vegetation communities. Permanent impacts to non -native vegetation communities/land covers totaling 0.74 acres are not considered significant because these land covers are not considered sensitive; they are non-native and provide little biological resource value.
Direct permanent impacts to native wetland and coastal sage scrub communities would be considered significant absent mitigation. The project will result in the preservation of 7.327.1 acres of sensitive upland vegetation communities and 0.756 acres of wetland vegetation communities (including
0.02 acres of restored wetland vegetation) (MM-BIO-1). Implementation of MM-BIO-1 will provide for the required 1:1 mitigation for impacts to coastal sage scrub and the preservation of 0.756 acres of native wetlands and vernal pools will provide partial mitigation for impacts to wetland vegetation communities. To compensate for the loss of wetland vegetation communities the project will implement invasive species removal and restoration as well as vernal pool r estoration (MM-BIO-2).
Implementation of MM-BIO-1 and MM-BIO-2 would reduce potential direct, permanent impacts to less than significant.
Indirect impacts to vegetation during construction may include dust, which could disrupt plant vitality in the short term, construction -related soil erosion and runoff. Implementation of industry -standard construction and storm water BMPs including dust co ntrol, erosion control, and water quality
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protection would be required for the project to obtain a grading permit. Implementation of these dust, erosion control, and water quality protection measures during construction, including consistency with the Construction General Permit Order 2009-009-DWQ, would reduce any potential short-term indirect impacts on adjacent vegetation communities to a level that is less than significant.
Implementation of the project would result in significant impacts to sensitive natural communities (i.e., Arundo-Dominated Riparian, disturbed and emergent wetland, San Diego Mesa Claypan vernal pool, Southern Willow scrub, Tamarisk scrub, Diegan coastal sage scrub [including baccharis-dominated], Valley Needlegrass grassland, wildflower field, and non -native grassland [broadleaf-dominated]). Native habitat creation/restoration/preservation of impacted habitats would fully compensate for the loss of habitat and reduce impacts to below a level of significance. With the implementation of MM-BIO-1 and MM-BIO-2, impacts on sensitive natural communities would be less than significant with mitigation incorporated.
Threshold #3: Would the project have a substantial adverse effect on state or federally protected wetlands (including, but not limited to, marsh, vernal pool, coastal, etc.) through direct removal, filling, hydrological interruption, or other means?
The project would result in impacts to aquatic resources which are potentially subject to USACE jurisdiction pursuant to CWA Section 404 (33 USC 1344), waters of the state potentially subject to the RQWCB jurisdiction pursuant to CWA Section 401 and the Porter -Cologne Water Quality Control Act, and stream and riparian habitats potentially subject to regulation by the CDFW pursuant to CFGC Section 1600. Table 3.3-6 provides a summary of the proposed impacts.
Table 3.3-6
Impacts to Jurisdictional Aquatic Resources
Regulating Agency Jurisdictional Resource On-Site Acreage Impacts (acres) USACE/RWQCB Non-wetland waters 0.05 0.05
Total USACE/RWQCB 0.05 0.05
CDFW Streambed 0.09 0.09
Riparian habitat – Disturbed wetland 0.11 0.11
Total CDFW* 0.20 0.20
Notes:
USACE = U.S. Army Corps of Engineers; RWQCB = Regional Water Quality Control Board; CDFW = California Department of Fish and Wildlife
Overall, the project would result in impacts to 0.09 acres of streambed and 0.11 acres of associated riparian habitat regulated by CDFW. Approximately 0.05 acre s of non-wetland waters regulated by USACE and RWQCB would be permanently impacted. Mitigation for impacts to jurisdictional aquatic resources would occur through the on-site preservation of 0.756 acres of emergent wetland and vernal pools (MM-BIO-1) as well as on-site invasive species removal and vernal pool restoration (MM-BIO-2).
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In addition, all impacts to jurisdictional aquatic resources would require consultation with the regulatory agencies (MM-BI0-13).
Indirect impacts would be limited to short-term construction impacts related to construction runoff and dust. However, all project ground-disturbing activities would be subject to the typical restrictions (e.g., BMPs) and requirements that address erosion and runoff, including those of the National Pollutant Discharge Elimination System permit program and preparation of a Stormwater Pollution Prevention Plan, including consistency with the Construction General Permit Order 2009 -009-DWQ. With implementation of these BMPs and permit conditions, potential indirect impacts to preserved jurisdictional aquatic resources in the project site would be less than significant.
In conclusion, implementing the project would result in significant impacts to protected jurisdictional resources under potential regulation by USACE, RWQCB, and or CDFW. The project would be required to secure the necessary regulatory permits prior to impacts per MM-BIO-13. It is anticipated that a 404 permit from the USACE, 401 Certification from the RWQCB, and a 1600 agreement from CDFW would be needed. If the wetlands or waters on-site are ruled non-jurisdictional by USACE, it is anticipated that a Waste Discharge Requirement Permit from RWQCB and a 160 0 agreement from CDFW would be required, such that impacts would be reduced to less than significant with mitigation incorporated.
Threshold #4: Would the project interfere substantially with the movement of any native resident or migratory fish or wildlife species or with established native resident or migratory wildlife corridors, or impede the use of native wildlife nursery sites?
Development on the project site would not interfere with wildlife movement or nursery functions. The project site does not support fish habitat, is entirely bounded by existing development, is not contiguous with native habitats, and is outside of areas where wildlife movement opportunities do occur (along undeveloped open space habitat corridors). Areas may be used by smaller urban-adapted mammal species and bird species, but such areas are not considered refuge as a wildlife corridor or habitat linkage.
Based on the analysis above, development on the project site would not interfere or impede with wildlife movement, corridors, or nursery sites; and impacts would be less than significant.
Threshold #5: Would the project conflict with any local policies or ordinances protecting biological resources, such as a tree preservation policy or ordinance? Section 14.12.200 of the City’s Municipal Code provides that where a permit is required for excavation, fill, or obstruction for installation or repair of utilities under any public street, sidewalk, trail, or public place, such construction should be located away from trees. As described in Chapter 2, Project Description, the project would likely require utility work within public streets including sewer and water improvements, storm drainage facilities, and roadway network improvements . However, as a
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requirement under the City’s Municipal Code to obtain an excavation permit, such construction will be located away from trees and not otherwise require the removal of trees within the public right-of-way.
In the case that construction away from trees is unavoidable, the applicant will confer with the Director of Development Services, or their designee, to determine how best to avoid conflicts with mature trees and their root systems . The project would be required to demonstrate compliance with this requirement to the satisfaction of the Director to obtain an excavation permit.
Per General Plan Policy COS-2.6, healthy mature trees are to be preserved, where feasible; and where removal is necessary, trees shall be replaced at a ratio of 1:1. The project would incorporate a conceptual landscape plan that would detail tree planting plans and would be drafted to be aligned with all relevant General Plan policies, including this tree preservation policy.
Further, as discussed in Section 3.10 of this EIR , the project would be consistent with the City ’s General Plan Conservation and Open Space Element . The project would conserve existing biological resources to the extent feasible and incorporate open space area into the project design plans which would be subject to City review. Therefore, it is determined that the project would not conflict with any local policies or ordinances protecting biological resources, such as a tree preservation policy or ordinance and impacts would be less than significant.
Threshold #6: Would the project conflict with the provisions of an adopted Habitat Conservation Plan, Natural Community Conservation Plan, or other approved local, regional, or state habitat conservation plan?
The project is not located within a designated Biological Core Linkage Area or Focused Planning Area, and therefore, it is consistent with the conservation policies of the Draft San Marcos Subarea Plan. In addition, the project would be required to conform to the goals and policies in the City of San Marcos General Plan (City of San Marcos 2012) related to the protection of biological resources. Following implementation of proposed mitigation measures, the project is expected to be found to be in conformance with the Draft San Marcos Subarea Plan and the General Plan. Therefore, with implementation of proposed mitigation, impacts to regional resource planning would be less than significant.
3.3.6 Cumulative Impact Analysis
Special-Status Plant and Animal Species
Cumulative impacts consider the potential regional effects of a project and how a project may affect an ecosystem or one of its members beyond the project limits and on a regional scale. As discussed, the project would have potentially significant impacts associa ted with coastal California gnatcatcher and least Bell’s vireo; however, implementation of MM-BIO-3 through MM-BIO-13 would reduce these impacts to a level below significance. The project would not have significant impacts on special-status plant species.
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Similar to the project, cumulative projects would be required to mitigate impacts by avoiding the grading or clearing of suitable habitat for sensitive wildlife during the breeding season, or by conducting pre-construction surveys to avoid sensitive species if construction would occur during the breeding season. Through the implementation of required mitigation, impacts to present and potentially present sensitive wildlife species would be reduced to a level below significance for the project and for cumulative projects. Therefore, cumulative impacts with regard to special-status wildlife species would not be cumulatively considerable.
Sensitive Natural Communities
The project would directly contribute to the cumulative loss of 1.09 acres of wetland communities,
0.840.69 acres of coastal sage scrub , and 1.080.84 acres of “other lands .” Impacts to wetland communities include 0.12 acres of Arundo-dominated riparian and 0.54 acres of tamarisk scrub (see Table
3.3-5). Permanent impacts to non-native vegetation communities/land covers totaling 0.74 acres are not considered significant because these land covers are not considered sensitive; they are non-native and provide little biological resource value. Direct permanent impacts to native wetland and coastal sage scrub communities would be considered significant absent mitigation. The project will result in the preservation of 7.327.1 acres of sensitive upland vegetation communities and 0.756 acres of wetland vegetation communities (MM-BIO-1). Implementation of MM-BIO-1 will provide for the required 1:1 mitigation for impacts to coastal sage scrub and the preservation of 0.756 acres of wetlands and vernal pools will provide partial mitigation for impacts to wetland vegetation communities. To compensate for the loss of wetland vegetation communities the project will implement invasive species removal and restoration as well as vernal pool restoration (MM-BIO-2). Implementation of MM-BIO-1 and MM-BIO-2 would reduce potential project impacts to less than significant.
Cumulative projects would be required to mitigate their individual impacts to sensitive vegetation communities through either on -site preservation/restoration and/or off -site habitat acquisition, typically at a 2:1 or 3:1 ratio. Therefore, because the project and cumulative projects would be required to mitigate for habitat loss, impacts related to the loss of sensitive vegetation communities would not be cumulatively considerable.
Jurisdictional Waters and Wetlands
As analyzed above, implementing the project would result in potentially significant impacts to protected jurisdictional resources regulated by the USACE, RWQCB, and CDFW. The project would be required to secure the necessary regulatory permits prior to impacts per mitigation measure MM-BIO-13. It is anticipated that a 404 permit from the USACE, 401 Certification from the RWQCB, and a 1600 agreement from CDFW would be needed. If the wetlands or waters on-site are ruled non- jurisdictional by USACE, it is anticipated that a Waste Discharge Requirement Permit from RWQCB and a 160 0 agreement from CDFW would be required. Mitigation for impacts to jurisdictional aquatic resources would occur through the on-site preservation of 0.8 acres of emergent wetland and vernal
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pools (MM-BIO-1) as well as on-site invasive species removal and vernal pool restoration (MM-BIO-2).
In addition, all impacts to jurisdictional aquatic resources would require consultation with the regulatory agencies (MM -BI0-13). The proposed mitigation would compensate for impacts to jurisdictional resources such that impacts would be reduced to below a level of significance.
Like the project, it is presumed that all reasonably foreseeable cumulative projects would be required to conform to existing regulations with respect to avoidance, minimization, and mitigation of impacts to sensitive habitat, achieving no -net-loss of wetl ands and like/kind replacement for impacts to sensitive habitat that cannot be avoided. The regulatory permitting process ensures that every project with unavoidable impacts on jurisdictional resources implements required avoidance, minimization, and compensatory mitigation measures and obtains the appropriate permits. Projects in the region are required to meet a no -net-loss standard for both function and spatial area of wetland and non - wetland resources. Therefore, the project would not contribute to a cumulative impact to jurisdictional waters and wetlands.
Conflict with Local Ordinances/Tree Preservation Policies Like the project, it is presumed that all reasonably foreseeable cumulative projects would be required to conform to the City’s Municipal Code requirements and General Plan Policies for tree replacement.
Therefore, the project would not contribute to a cumulative impact related to a conflict with tree preservation policies.
Conflict with Adopted Habitat Management Plan
The project is not located within a designated Biological Core Linkage Area or Focused Planning Area, and therefore, it is consistent with the conservation policies in the Draft San Marcos Subarea Plan. In addition, the project would be required to conform to the goals and policies in the City of San Marcos General Plan (City of San Marcos 2012) related to the protection of biological resources. Following implementation of proposed mitigation measures, the project is expected to be found to be in conformance with the Draft San Marcos Subarea Plan and the General Plan. Therefore, no impacts related to regional resource planning are anticipated.
In sum, all reasonably foreseeable cumulative projects within the City of San Marcos would be required to be consistent with the conservation policies in the Draft San Marcos Subarea Plan and goals and policies in the City of San Marcos General Plan related to the protection of biological resources .
Impacts would be assessed on a regional basis and mitigated pursuant to CEQA, and those projects within the City ’s jurisdiction would be reviewed by the City during the project review and approval process. For these reasons, project impacts to biological resources related to regional resource planning are not cumulatively considerable.
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3.3.7 Mitigation Measures
MM-BIO-1 through MM-BIO-13 outlined below would reduce potential impacts related to special status wildlife, would reduce potential impacts on sensitive natural communities , and would ensure that the appropriate permits are obtained and that impact s are compensated in accordance with USACE, RWQCB, and CDFW requirements. With implementation of MM -BIO-1 through MM -BIO--13, impacts to biological resources as a result of project implementation would be reduced a level of less than significant.
MM-BIO-1 On-Site Preservation. Impacts to sensitive vegetation shall be mitigated through the on-site preservation of 8.077.85 acres of sensitive upland and wetland vegetation. The project shall result in the preservation of 7.327.1 acres of sensitive upland vegetation communities and 0.7 56 acres of wetland vegetation communities (which includes
0.02 acres of restored areas per MM -BIO-2). A land manager shall be identified to ensure that the project is managed and protected in perpetuity. A conservation easement for the 7.85 acres shall be recorded prior to the issuance of a grading permit or other timing agreed upon by the Planning Division Director or their designee.
MM-BIO-2 On-site Habitat Restoration. On-site habitat restoration will consist of the removal and restoration of invasive species, vernal pool restoration, and development of a habitat restoration plan.
Invasive Species Removal. The 0.02 acres of tamarisk scrub will be restored to native emergent wetland habitat through the removal of the tamarisk and other non -native plant species. Tamarisk will be cut and stump treated with herbicide, and the other non-native species will be removed with a combination of herbicide application, mowing (line trimmers), and hand weeding. With the removal of those invasive species, the site will be planted and seeded to establish native emergent wetland species found on site, including but not limited to pale spikerush, Mexican rush, iris -leaf rush, alkali mallow (Malvella leprosa), and pickleweed.
Vernal Pool Restoration. Vernal pool restoration will include some minor recontouring of the existing vernal pool basin where appropriate, mostly where vernal pools have been altered by road ruts, trail berms, and other past disturbances to the site. Any recontouring will avoid impacts to existing vernal pools and existing sensitive species and is intended to develop new pools or to expand pools from existing locations. Along with this minor recontouring, weed control will also be conducted in the vernal p ools and surrounding watershed areas. Weed control will consist of a combination of herbicide application, mowing (line trimmers), and hand weeding. Vernal pools on site that are low in diversity, particularly those at the south end of the project, will be planted and seeded with vernal pools species known from the site. Seed collected for
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this purpose will come from on-site sources only. This will include, but is not limited to San Diego button celery, spreading navarretia, pale spikerush, annual coast plantago (Plantago elongata ), aquatic pygmy plant ( Crassula aquatica ), toad rush ( Juncus bufonius), smooth boisduvalia ( Epilobium campestris ), and wooly marbles (Psilocarphus brevissimus). Mitigation will not occur within the San Diego County Water Authority owned parcel s. The project applicant will consult with the U.S. Fish and Wildlife Service to ensure that the mitigation plan does not impact listed species.
Habitat Restoration Plan. The applicant shall prepare a conceptual habitat restoration plan outlining the restoration described above. Upon approval a 5-year implementation effort would follow the plan, including topographic reconstruction, weed control, seeding, container planting, irrigation, and a program of monitoring and reporting.
The restoration plan shall be prepared by persons with expertise in southern California ecosystems and native plant revegetation techniques. The plan should include, at a minimum: (a) a description of the mitigation site; (b) the plant species to be used, container sizes, and seedin g rates; (c) a schematic depicting the mitigation area; (d) planting schedule; (e) a description of the irrigation methodology; (f) measures to control non-native vegetation on site; (g) specific success criteria; (h) a detailed monitoring program; (i) contingency measures should the success criteria not be met; and (j) identification of the party responsible for meeting the success criteria and providing for conservation of the mitigation site in perpetuity. As part of the mitigation planning a PAR-like cost evaluation will be developed and approved by USFWS to help determine long term costs in the endowment required to support those costs. The applicant is required to fund the endowment before the issuance of grading permits, and the endowment agreement shall be approved by USFWS.
MM-BIO-3 Landscaping. The applicant shall ensure that development landscaping adjacent to on- or off-site habitat does not include exotic plant species that may be invasive to native habitats. Exotic plant species not to be used include any species listed on the California Invasive Plant Council ’s (Cal -IPC) “Invasive Plant Inventory” List. In addition, landscaping should not use plants that require intensive irrigation, fertilizers, or pesticides adjacent to preserved lands and water runoff from landscaped areas should be directed away from the bi ological conservation easement area and contained and/or treated within the development footprint . The applicant shall ensure that development lighting adjacent to all on- or off-site habitat shall be directed away from and/or shielded so as not to illuminate native habitats.
MM-BIO-4 Temporary Installation Fencing. The project applicant shall temporarily fence the limits of the project impact footprint and install other appropriate sediment trapping devices
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to prevent additional impacts to, and the spread of silt from the construction zone into, adjacent habitat s to be avoided. Fencing and sediment trapping devices will be installed in a manner that does not impact habitats to be avoided.
If work occurs beyond the fenced limits of impact, all work will cease until the problem has been remedied to the satisfaction of the City. Any habitat impacts that occur beyond the authorized work will be offset at ratios approved by the City. Temporary construction fencing and sediment trapping devices will be removed upon project completion.
MM-BIO-5 Environmental Awareness Training . A Workers Environmental Awareness Training Program shall be implemented with the contractor and all active construction personnel prior to construction to ensure knowledge of sensitive wildlife which may occur on site including coastal California gnatcatcher and least Bell’s vireo, their habitat, and general compliance with environmental/permit regulations and mitigation measures.
At a minimum, training will include a discussion of the following topics: (1) the purpose for resource protection; (2) a description of the coastal California gnatcatcher and least Bell’s vireo and their habitat; (3) descriptions of the special -status plants and their habitat, (4) the MMs outlined in this report that should be implemented during project construction to conserve the sensitive resource, including strictly limiting activities, vehicles, equipment, and construction materials to the fenced project footprint to avoid sensitive resource areas in the field (i.e., avoided areas delineated on maps or on the project site by fencing); (4) environmentally responsible construction practices; (5) the protocol to resolve conflicts that may arise at any time during the construction process; and, (6) the general provisions of the FESA and California Endangered Species Act (CESA), the need to adhere to the provisions of the FESA and CESA, and the penalties associated with violating the FESA and CESA.
MM-BIO-6 Breeding Season Avoidance . The removal of coastal sage scrub and wetland vegetation from the project impact footprint will occur from September 1 to February 14 to avoid the bird breeding season. Further, to the maximum extent practicable, grading activities associated with construction of the project will occur from September 1 to February 14 to avoid the breeding season. If project construction must occur during the breeding season, MM-BIO-10 and MM-BIO-11 will be implemented.
MM-BIO-7 Work Hours . Project construction will occur during daylight hours. However, if temporary night work is required, night lighting shall abide by city standards and shall be, selectively placed, shielded, and directed away from natural habitats.
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MM-BIO-8 Construction Best Management Practices . The project applicant will ensure that the following conditions are implemented during project construction in order to minimize potential impacts to sensitive vegetation and species:
1. Employees will strictly limit their activities, vehicles, equipment, and construction materials to the fenced project footprint;
2. To avoid attracting predators, the project site will be kept as clean of debris as possible. All food related trash items will be enclosed in sealed containers and regularly removed from the site;
3. Pets of project personnel will not be allowed on the project site; and,
4. Impacts from fugitive dust will be avoided and minimized through watering and other appropriate measures consistent with the Construction General Permit Order 2009-009-DWQ.
MM-BIO-9 Biological Monitor Requirements and Duties. A qualified biologist will be on site daily during initial clearing/grubbing and weekly during grading activities within 500 feet of coastal California gnatcatcher and least Bell’s vireo habitat to ensure compliance with all project-imposed mitigation measures. The biologist will be available during pre - construction and construction phases to review grading plans, address protection of sensitive biological resources, monitor ongoing work, and maintain communications with the project’s engineer to ensure that issues relating to coastal California gnatcatcher, least Bell’s vireo and their habitat are appropriately and lawfully managed.
The qualified biological monitor will also be responsible for the following duties:
1. Oversee installation of and inspect temporary fencing and erosion control measures within or up-slope of avoided and/or preserved areas a minimum of once per week during installation and daily during all rain events until established to ensure that any breaks in the fence or erosion control measures are repaired immediately.
2. Periodically monitor the work area to ensure that work activities do not generate excessive amounts of dust.
3. Halt work, if necessary, and confer with the USFWS and City to ensure the proper implementation of species and habitat protection measures. The biologist will report any violation to the USFWS and City within 24 hours of its occurrence.
4. Submit weekly letter reports (including photographs of impact areas) via regular or electronic mail (email) to the City during clearing/grubbing of potential habitat and/or project construction resulting in ground disturbance within 500 feet of avoided pot ential habitat. The weekly reports will document that authorized impacts were not exceeded and general compliance with all conditions. The reports will also outline the duration of monitoring, the location of construction
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activities, the type of construction that occurred, and equipment used. These reports will specify numbers and locations of any coastal California gnatcatcher/least Bell ’s vireo and nests, sex, observed behavior (especially in relation to construction activities), and remedial measures employed to avoid, minimize, and mitigate impacts to coastal California gnatcatcher/least Bell’s vireo and nests.
5. Submit a final report to the City within 60 days of project completion that includes the following: (1) as-built construction drawings for grading with an overlay of any active nests; (2) photographs of habitat areas during pre -construction and post - construction conditions; and (3) other relevant summary information documenting that authorized impacts were not exceeded and that general compliance with the avoidance/minimization provisions and monitoring program as required by the USFWS were achieved.
MM-BIO-10 California Gnatcatcher Survey . For initial clearing/grubbing of coastal California gnatcatcher habitat within the project development footprint, a biologist holding a Section 10(a)(1)(A) permit shall perform a minimum of three (3) focused surveys, on separate days, to determine the pres ence of California gnatcatchers or nests in the project impact footprint. Surveys will begin a maximum of seven (7) days prior to performing initial clearing/grubbing, and one survey will be conducted the day immediately prior to the initiation of clearing/grubbing. If any coastal California gnatcatchers are found in the project impact footprint, the biologist will direct construction personnel to begin clearing/grubbing in an area away from the coastal California gnatcatchers and attempt to flush coastal California gnatcatchers away from clearing/grubbing so that coastal Californ ia gnatcatchers will not be injured or killed by clearing/grubbing activities. If an active coastal California gnatcatcher nest is found, the nest will be avoided until nesting is confirmed to be completed by the biologist. The project applicant will notify the USFWS at least seven (7) days prior to the initiation of surveys and within 24 hours of locating any California gnatcatcher and/or nest.
MM-BIO-11 California Gnatcatcher Nest Avoidance and Minimization Measures. If an active coastal California gnatcatcher (Polioptila californica californica) nest is found on site or within 500 feet of project grading activities, the biologist shall postpone work within 500 feet of the nest and contact the U.S. Fish and Wildlife Service (USFWS) and the City of San Marcos to discuss (1) the best approach to avoid/minimize impacts to nesting coastal California gnatcatchers (e.g., sound walls, noise monitoring); and (2) a nest monitoring program acceptable to USFWS. Subsequent to these discussions, work may be initiated subject to implementation of the agreed -upon avoidance/minimization approach and monitorin g program. If the biologist determines that bird breeding
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behavior is being disrupted, the project applicant shall stop work and coordinate with USFWS to review the avoidance/minimization approach. Upon agreement as to any necessary revisions to the avoidance/minimization approach, work may resume subject to the revisions and continued monitoring. Success or failure of an active nest shall be established by regular and frequent trips to the site, as determined by the biologist and through a schedule approved by the wildlife agencies. Monitoring of an active nest s hall continue until fledglings have dispersed or the nest has been determined to be a failure, as approved by USFWS.
MM-BIO-12 General Pre -Construction Surveys. This mitigation measure serves to avoid take of birds protected under the Migratory Bird Treaty Act and California Fish and Game Code during the nesting season.
Nesting Bird Survey. To avoid any direct impacts on raptors and/or any migratory birds protected under the Migratory Bird Treaty Act and California Fish and Game Code, removal of habitat that supports active nests on the proposed area of disturbance shall occur outside the nesting season for these species (which is February 15 through August 31, annually). If construction occurs during the nesting season then preconstruction nesting bird surveys must be conducted within 72 hours of construction -related activities. If nesting birds are detected by the biologist, the following buffers shall be established: 1) no work within 300 feet of a non-listed nesting migratory bird nest, and 2) no work within 500 feet of a listed bird or raptor nest. However, the biolog ist may reduce these buffer widths depending on site-specific conditions (e.g. the width and type of screening vegetation between the nest and proposed activity) or the existing ambient level of activity (e.g., existing level of human activity within the b uffer distance) in conjunction with consultation with the City. If construction must take place within the recommended buffer widths above, the project applicant will contact the City and Wildlife Agencies to determine the appropriate buffer.
MM-BIO-13 Federal and State Agency Permits. Prior to impacts occurring to U.S. Army Corps of Engineers (USACE), Regional Water Quality Control Board (RWQCB), and California Department of Fish and Wildlife (CDFW) (collectively, the Resource Agencies) jurisdictional aquatic resources, the project applicant or its designee shall obtain the following permits: USACE 404 permit, RWQCB 401 Water Quality Certification, and CDFW Fish and Game Code 1600 Streambed Alteration Agreement. The project applicant will consult with the U.S. Fish and Wildlife Service and get approval of the mitigation plan to ensure that it does not impact listed species.
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3.3.8 Conclusion
As described throughout Section 3.3.5, Project Impact Analysis, implementation of the project would result in potentially significant impacts to biological resources (Impact BIO-1, Impact BIO-2, and Impact BIO-3). H owever, compliance with existing regulations and implementation of proposed mitigation measures MM-BIO-1 through MM-BIO-13 outlined in Section 3.3.7, would reduce impacts to biological resources to a level of less than significant. Implementation of proposed mitigation, and City review of project plans for the site would ensure impacts to biological resources would be reduced to a level of less than significant.
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Way
Vegetation Communities and Land Covers
ARU, Arundo-Dominated Riparian
CSS, Diegan Coastal Sage Scrub
CSSB, Diegan Coastal Sage Scrub:
Baccharis-dominated
DH, Disturbed Habitat
DW, Disturbed Wetland
EUC, Eucalyptus Woodland
EW, Emergent Wetland
HW, Herbaceous wetland
NNGA, Non-Native Grassland: Artichoke-
Thistle-Dominated
NNGB, Non-Native Grassland: Broadleaf-
Dominated
SWS, Southern Willow Scrub
TS, Tamarisk Scrub
VGL, Valley Needlegrass Grassland
VP, San Diego Mesa Claypan Vernal Pool
WF, Wildflower Field
FIGURE 3.3-1
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Brofil, thread-leaved brodiaea (Brodiaea filifoliai)
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Eryaripar, San Diego button-celery (Eryngium aristulatum var. parishii) !!H Wildlife
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3.4 Cultural Resources
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3.4 CULTURAL RESOURCES
This section describes the existing cultural resources of the proposed Hughes Circuits Project (project), identifies associated regulatory requirements, evaluates potential impacts, and identifies mitigation measures related to implementation of the project.
The analysis in this section relies, in part, on the Archaeological Resources Inventory Report for the Hughes Circuits Project, City of San Marcos, California (Archaeological Resources Report) prepared by Dudek on January 13, 2023. The archaeological resources report included a record search, archival research, correspondence with Native American contacts, and a pedestrian survey. The analysis also considers the California Environmental Quality Act (CEQA) Guidelines Appendix G and applicable state and local regulations, including the City of San Marcos General Plan. The Archaeological Resources Report is included as Appendix D to this environmental impact report (EIR).
Table 3.4-1 summarizes the project- and cumulative-level cultural resources impacts, by threshold.
Table 3.4-1
Cultural Resources Summary of Impacts
Threshold of Significance
Project-Level
Impact
Cumulative-Level
Impact
Significance
Determination
#1 – Cause a substantial adverse change in
the significance of a historical resource
pursuant to Section 15064.5.
No Impact No Impact No Impact
#2 – Cause a substantial adverse change in
the significance of an archaeological
resource pursuant to Section 15064.5.
Potentially
Significant
Less than
Significant with
Mitigation
Less than
Significant with
MM-CR-1 through
MM-CR-3
#3 – Disturb any human remains, including
those interred outside of dedicated
cemeteries.
Potentially
Significant
Less than
Significant with
Mitigation
Less than
Significant with
MM-CR-1 through
MM-CR-4
3.4.1 Existing Conditions
The project area, as analyzed in the Archaeological Resources Report, consists of the entire of the project site, approximately 10.46 acres (Assessor’s Parcel Numbers 219-223-20-00 and 219-223-22-00) (see Figure 3.16-1, Area of Potential Effects (APE)). The entire project area is undeveloped and contains no structures. Adjacent land uses include mixed commercial development to the north and south, a public recreation park (Bradley Park) to the west, and undeveloped land to the east. The Las Posas Branch tributary to San Marcos Creek is located on the border of the western section of the project area, and a second tributary runs through the project area on the eastern side to San Marcos Creek.
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The project area predominantly contains grass, thistles, Hardy ice plants, and sage. Modern debris (e.g., refuse) is strewn throughout the project area and a homeless encampment was observed in the bushes on the northwestern portion of the project area. The project site falls within Section 16 of Township 12 South, Range 3 West of the San Marcos, California 7.5-minute Quadrangle.
Methodology
Records Search
Dudek conducted a California Historical Resources Information Systems records search of the project APE and a one-mile radius buffer at the South Coastal Information Center (SCIC) on January 31, 2022.
The records search results indicate that 53 previous cultural resources studies have been conducted within 1 mile of the project area. Of the 53 previous studies, five studies intersect the project area.
These studies consist primarily of an archaeological inventory report, two cultural resource reconnaissance reports, an EIR, and a records search and literature review. Overall, 100% of the project area has been previously studied.
The SCIC records search did not identify any cultural resources within the project area. The records search did identify eight cultural resources within the one-mile search radius buffer of the project area.
Of the total eight resources identified in the 1-mile buffer, six are prehistoric resources and two are historic resources. No historic addresses are located within the project area, however, two are located within the 1-mile search radius. Refer to Appendix D for further details.
Archival Research
Dudek conducted an on -line review of historic aerial photographs of the project area and general vicinity, to help determine the possible development and land use of the project area in the past.
Historic aerial photographs of the project APE were available for 1938, 1947, 1953, 1964, 1967, 1980–1991, 1993–2000, 2002, 2003, 2005, 2009, 2010, 2012, 2014, 2016, and 2018 (NETR 2022). The historical aerials from 1938 to 1967 revealed that project area was undeveloped. By 1978, some dirt trails can be observed w ithin the area and to the north of the area, grading was observed, and two structures were developed. By 1980, the road for South Pacific Street is developed, the surrounding properties have been graded, and residential/commercial development is present. The aerials from 1981–1984 do not reveal any changes to the area. By 1985, some light surface disturbance is observed within a small section of the southern area. The 1986 aerial shows some slight disturbance to the area in the form of dirt trails. The aeri als from 1987 –1994 do not reveal any changes to the area. The 1993 aerial shows some disturbance to the eastern portion of the area, and by 1996, dirt trails or a dirt road become more prominent within the area. The aerials from 1997 to 2018 do not reveal any changes to the area. The entire portion of the project area has remained undeveloped. No historic structures are located within the project area. The review of the
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Hughes Circuits Project Environmental Impact Report March 2024 City of San Marcos 3.4-3
aerial photographs reveals that a majority of the project area has not been highly disturbed by earth moving activities.
Historic topographic maps of the project area were reviewed (earliest map available is 1893). A creek is observed within the western section of the project area, however, on the 1979 topographic map , the creek is no longer observed within the project area. The historic topographic maps do not reveal any historic structures located within the project area.
Dudek reviewed a geotechnical report prepared for the project area (Appendix E). The report details the results of six exploratory bores to a maximum depth of 14 feet on September 1, 2021, however, the report only covered a small portion of the western section of the project area. Undocumented fill was encountered to a depth of approximately 2 feet. Alluvium was encountered in all trenches to depths ranging between 3.5 to 10 feet. Tertiary -age Santiago Formation was encountered below the undocumented fill and alluvium across the site, at depths between 3.5 and 10 feet below existing grade.
According to the U.S. Department of Agriculture Natural Resources Conservation Services (USDA 2022), three soil types are mapped in the project area, including Las Flores loamy fine sand, 2% to 9% slopes, located in the central section of the project area, Las Flores -Urban land complex, 2 % to 9% slopes, located along the western border of the project area, and Placentia sandy loam, thick surface, 0% to 2% slopes, located along the southern and eastern sections of the project area. The Las Flores soil series generally occurs on hillslopes, formed in residuum weathered from siliceous calcareous sandstone, and are typically at an elevation of 700 feet, The Placentia soil series generally occur in settings with alluvial fan s, formed in alluvium derived from granite, and are typically at elevations ranging from 50 to 2,500 feet. Reoccurring alluvial action and flooding serve to support the development and presence of cultural deposits in the area. Since there are alluvial soils present throughout the project area, there is moderate potential for subsurface cultural resources.
Native American Heritage Commission and Native American Outreach Letters Dudek requested a Native American Heritage Commission (NAHC) search of the Sacred Lands File on January 31, 2022, for the project area. The Sacred Lands File consists of a database of known Native American resources. These resources may not be included in the SCIC database. The NAHC replied on March 24, 2022, with negative results (Appendix D). The NAHC additionally provided a list of Native American tribes and individuals/organizations with traditional geographic associations that might have knowledge of cultural resources in this area.
Thirty-one outreach letters were mailed on March 24, 2022 , to all Native American group representatives included on the NAHC contact list (Appendix D). These letters solicited, or attempted to elicit additional information relating to Native American resources that may be impacted by the project. Native American representatives were requested to define a general area where known resources intersect the project area. Three responses have been received to date. A response was
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received from the Rincon Band of Luiseno Indians on April 25, 2022 stating that the project is located within a culturally-sensitive area and the potential exists that the project may impact tangible Tribal Cultural Resources (TCRs), Traditional Cultural Landscapes, and potential Traditional Cultural Properties. A response was received from the San Luis Rey Band of Mission Indians on April 26, 2022, stating that they are aware of cultural resources within close proximity to the project and recommends including a Luiseño Native American monitor during all ground disturbing activities. A response was received from the San Pasqual Band of Mission Indians on May 5, 2022 , stating that the project is within their Traditional Use Area. The letters have been forwarded to the City. No other communications between Dudek and the tribes has occurred since then. The NAHC correspondence is included in Appendix D.
In compliance with Assembly Bill (AB) 52, the City of San Marcos (City), as lead agency, is responsible for conducting government to government consultation with pertinent tribal entities. The City mailed AB 52 notifications on May 3, 2022 , to California Native American Tribal representatives (that have requested notification) who are traditionally or culturally affiliated with the geographic area of the project. ThreeTwo tribes requested consultation under AB 52, including the Rincon Band of Luiseño Indians on May 20, 2022 , and the San Luis Rey Band of Mission Indians on June 6, 2022 , and the San Pasqual Band of Diegueño Mission Indians on May 11, 2023. The Rincon Band of Luiseño Indians agreed with the mitigation measures proposed by Dudek in the archaeological resources report, which includes archaeological and tribal monitoring, and protocols for the discovery of cultural material and human remains. Additionally, the Rincon Band of Luiseño proposed that if export of soil is pl anned, consultation with the affiliated tribes will have to be initiated, and this was included in the mitigation measures. The Rincon Band of Luiseño concluded AB 52 consultation on December 20, 2022. The San Luis Rey Band agreed with the proposed measure s for tribal cultural resources for the project’s environmental document. The San Luis Rey Band of Mission Indians concluded AB 52 consultation on January 12, 2023. The City provided the San Pasqual Band of Diegueño Mission Indians with the project Cultura l Reports on May 11, 2023 . T he San Pasqual Band of Diegueño Mission Indians requested inclusion of a Kumeyaay monitor during construction in a letter to the City on January 10, 2024. The City confirmed a Kumey aay monitor would be included in the project ’s conditions of approval, and the San Pasqual Band of Diegueño Mission Indians concluded AB 52 consultation on February 14, 2024.
Intensive Pedestrian Survey
A Dudek archaeologist conducted an intensive level pedestrian survey of the project area on February 3, 2022. A Luiseño Native American monitor from Saving Sacred Sites participated in the pedestrian survey. All survey work was conducted employing standard archaeological procedures and techniques consistent with the Secretary of the Interior Standards. Five -meter interval survey transects were conducted in an east-west direction for the project area. Within the transects, the ground surface was examined for prehistoric artifacts (e.g., flaked stone tools, tool -making debris, stone milling tools,
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ceramics, fire-affected rock), soil discoloration that might indicate the presence of a cultural midden, soil depressions, features indicative of the current or former presence of structures or buildings (e.g., standing exterior walls, post holes, foundations), and historic artifacts (e.g., metal, glass, ceramics, building materials). Ground disturbances such as burrows, cut banks, and drainages were also visually inspected for exposed subsurface materials.
The project area is relatively flat and undeveloped. Some disturbances were observed, such as a dirt road on the eastern portion of the project area, and a drainage feature from a sewer running north to south. Ground visibility was poor (0 %–20%) in areas where the ground surface was obscured by vegetation. Approximately 75% of the area was obscured by grass, thistles, Hardy ice plants, and sage.
Modern debris (e.g., refuse) is strewn throughout the area and a homeless encampment was observed in the bushes on the northwestern portion of the project area. The pedestrian survey did not identify any cultural or built environment resources within the project area.
3.4.2 Regulatory Setting
The following section provides a general description of the applicable regulatory requirements pertaining to cultural resources, including state, and local guidelines.
State
California Register of Historical Resources and the California Environmental Quality Act Under CEQA, the term “historical resource” includes but is not limited to “any object, building, structure, site, area, place, record, or manuscript which is historically or archaeologically significant, or is significant in the architectural, engineering, scientific, economic, agricultural, educational, social, political, military, or cultural annals of California” (California Public Resources Code [PRC] Section 5020.1[j]). In 1992, the California legislature established the California Register of Historic al Resources (CRHR) “to be used by state and local agencies, private groups, and citizens to identify the state’s historical resources and to indicate what properties are to be protected, to the extent prudent and feasible, from substantial adverse change” (PRC Section 5024.1[a]). A resource may be listed as an historical resource in the CRHR if it meets any of the following National Register of Historic Places criteria (PRC Section 5024.1[c]):
• Associated with events that have made a significant contribution to the broad patterns of California’s history and cultural heritage.
• Associated with the lives of persons important in our past. • Embodies the distinctive characteristics of a type, period, region, or method of construction, or represents the work of an important creative individual, or possesses high artistic values. • Has yielded, or may be likely to yield, information important in prehistory or history.
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Resources less than 50 years old are not considered for listing in the CRHR, but may be considered if it can be demonstrated that sufficient time has passed to understand the historical importance of the resource (see 14 CCR Section 4852[d][2]).
The CRHR protects cultural resources by requiring evaluations of the significance of prehistoric and historic resources. The criteria for the CRHR are nearly identical to those for the National Register of Historic Places , and properties listed or formally designated as eligible for listing on the National Register of Historic Places are automatically listed on the CRHR, as are the State Historical Landmarks numbered 770 or higher and California Points of Historical Interest. The CRHR also includes properties designated under local ordinances or identified through local historical resource surveys. The State Historic Preservation Officer maintains the CRHR.
California Native American Graves Protection and Repatriation Act The California Native American Graves Protection and Repatriation Act (California Repatriation Act), enacted in 2001, required all state agencies and museums that receive state funding and that have possession or control over collections of human remains or cultural items, as defined, to complete an inventory and summary of these remains and items on or before January 1, 2003, with certain exceptions. The California Repatriation Act also provides a process for the identification and repatriation of these items to the appropriate tribes.
Native American Historic Cultural Sites (California Public Resources Code 5097 et seq.) State law addresses the disposition of Native American burials in archaeological sites and protects such remains from disturbance, vandalism, or inadvertent destruction; establishes procedures to be implemented if Native American skeletal remains are discovered during construction of a project; and establishes the NRHC to resolve disputes regarding the disposition of such remains. In addition, the Native American Historic Resource Protection Act makes it a misdemeanor punishable by up to 1 year in jail to deface or destroy an Indian historic or cultural site that is listed or may be eligible for listing in the CRHR.
California Health and Safety Code Section 7050.5 and Public Resources Code Section 5097.98 CEQA Guidelines Section 150064.5 assigns special importance to human remains and specifies procedures to be used when Native American remains are discovered. As described below, these procedures are detailed in California Health and Safety Code Section 705 0.5 and PRC Section 5097.98.
California law protects Native American burials, skeletal remains, and associated grave goods, regardless of their antiquity, and provides for the sensitive treatment and disposition of those remains.
Health and Safety Code Section 7050.5 requires that if human remains are discovered in any place other than a dedicated cemetery, no further disturbance or excavation of the site or nearby area
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reasonably suspected to contain human remains shall occur until the County coroner has examined the remains (California Health and Safety Section 7050.5[b]). If the coroner determines or has reason to believe the remains are those of a Native American, the coroner must contact the NAHC within 24 hours (California Health and Safety Code Section 7050.5[c]). In accordance with PRC Section 5097.98(a), the NAHC will notify the most likely descendant . With the permission of the landowner, the most likely descenda nt may inspect the site of discovery. Within 48 hours of being granted access to the site, the most likely descendant may recommend means of treatment or disposition, with appropriate dignity, of the human remains and associated grave goods.
Assembly Bill 52
California Assembly Bill 52, which took effect July 1, 2015, establishes a consultation process between California Native American Tribes and lead agencies to address tribal concerns regarding project impacts and mitigation to TCRs. PRC Section 21074(a) defines TCRs and states that a project that has the potential to cause a substantial adverse change to a TCR is a project that may have an adverse effect on the environment. A TCR is defined as a site, feature, place, cultural landscape, sacred place, and object with cultural value to a California Native American tribe that is either:
listed or eligible for listing in the CRHR or a local register of historical resources as defined in PRC Section 5020.1(k), or
determined by a lead agency , in its discretion and supported by substantial evidence, to be significant pursuant to criteria set forth in PRC Section 5024.1(c).
Local
City of San Marcos General Plan
Conservation and Open Space Element
The Conservation and Open Space Element of the City ’s General Plan contains several policies pertaining to the protection of archaeological and historic resources. The following goals and policies apply to the project (City of San Marcos 2012):
• Policy COS -2.5: Continue to review future development proposals to ensure that cultural resources (including prehistoric, historic, paleontological, and SB 18 Tribal resources) are analyzed and conserved in compliance with CEQA requirements. • Goal COS-11: Continue to identify and evaluate cultural, historic, archaeological, paleontological and architectural resources for protection from demolition and inappropriate actions. o Policy COS-11.1: Identify and protect historic and cultural resources including individual properties, districts and sites (e.g., archaeological sites) in compliance with CEQA.
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o Policy COS -11.2: Prohibit the demolition or removal of a historic structure without evaluation of the condition of the structure, the cost of rehabilitation, and the feasibility of alternatives to preservation in place including but not limited to relocation, or reconstruction off-site, and/or photo-preservation.
The project’s consistency with applicable General Plan goals and policies is discussed in Section 3.10, Land Use and Planni ng, of this EIR . As detailed in Section 3.10.4 , the project is consistent with the applicable General Plan goals and policies pertaining to cultural resources.
3.4.3 Thresholds of Significance
The determination of significance for cultural resources is based on CEQA Guidelines Appendix G.
Impacts to cultural resources would be significant if the project would:
• Threshold #1: Cause a substantial adverse change in the significance of a historical resource pursuant to CEQA Guidelines Section 15064.5
• Threshold #2: Cause a substantial adverse change in the significance of a n archaeological resource pursuant to CEQA Guidelines Section 15064.5
• Threshold #3: Disturb any human remains, including those interred outside of dedicated cemeteries
3.4.4 Project Impact Analysis
Impacts to cultural resources that may result from ground disturbing activities associated with the project are analyzed below.
Threshold #1: Would the project cause a substantial adverse change in the significance of a historical resource pursuant to CEQA Guidelines Section 15064.5?
Section 15064.5 of the CEQA Guidelines defines a historical resource as one that meets one or more of the following criteria:
1. Is listed in, or determined to be eligible by the State Historical Resources Commission, for listing in the CRHR; or
2. Is included in a local register of historical resources or identified as significant in a historical resource survey meeting the requirements of Section 5024.1(g) of the Public Resources Code; or
3. Is determined to be historically significant or significant in the architectural, engineering, scientific, economic, agricultural, educational, social, political, military, or cultural annals of California.
As identified in Section 3.4.1, no historic resources exist at the project area. Based upon archival research and aerial photographs, there are no historical -era (greater than 45 years old) structures
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present on the project area. The SCIC records search did not identify any historic addresses recorded within the project area. Therefore, it is determined that, no impact related to historical resources would occur as a result of project implementation.
Threshold #2 : Would the project cause a substantial adverse change in the significance of an archaeological resource pursuant to CEQA Guidelines Section 15064.5? As identified in Section 3.4.1, Existing Conditions, no cultural resources were found at the project area during the pedestrian survey or records search. As described in the Archaeological Resources Report (Appendix D), Dudek’s Phase I cultural resources inventory of the project indicates that there is a moderate sensitivity for identifying intact subsurface archaeological deposits during project implementation. the SCIC records search, NAHC Sacred Lands File search, Native American outreach, and intensive-level survey did not identify any cultural resources within the project area, however, the review of aerial photographs also reveals that a majority of the project area has not been highly disturbed by earth moving activities. In addition, two tributaries are located with in the project area, which would have been an attractive resource for prehistoric people. Reoccurring alluvial action and flooding serve to support the development and presence of cultural deposits in the area. Since there are alluvial soils present throughout the project area, there is a moderate potential that buried cultural resources deposits may be encountered during excavation. To further ensure project development would not result in potential impacts to cultural resources, the project would implemen t the cultural Mitigation Measure (MM-)CR-1 through MM -CR-3, outlined in Section 3.4.6 , Mitigation Measures .
Project implementation of MM -CR-1 through MM -CR-3 would ensure that potential impacts to archaeological resources pursuant to CEQA Guidelines Section 15064.5 would be less than significant with mitigation incorporated.
Threshold # 3: Would the project disturb any human remains, including those interred outside of dedicated cemeteries?
The project area is not used as a cemetery and is not otherwise known to contain human remains. The pedestrian field survey conducted for the project did not identify any human remains or find any indications that they would be expected to be found at the project area. However, although unlikely, there is the possibility of human remains being discovered during ground disturbing activities at the project area. Therefore, potential discovery of undocumented human remains on the project site could result in a potentially significant impact. If remains are discov ered during project construction activities, mitigation is proposed that would require work in the vicinity of the discovery be halted and procedures set forth in PRC Section 5097.98 and State Health and Safety Code Section 7050.5 be followed. The project would be required to comply with Section 7050.5 of the California Health and Safety Code and the project would implement MM -CR-4, outlined in Section 3.4.6. Project implementation of MM -CR-4 would ensure that potential impacts to human remains would be less than significant.
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3.4.5 Cumulative Impact Analysis
According to CEQA, the importance of cultural resources comes from the research value and the information they contain , as well as the loss of recognized cultural landmarks and vestiges of our community cultural history . The cumulative study area includes the project area and cumulative project sites.
As identified in Section 3.4.4, Project Impact Analysis, no historical resources exist at the project area.
Thus, no impact to historical resources would occur with implementation of the project. It is expected that cultural resources studies would be prepared for all cumulative projects to assess potential impacts, and that these projects would avoid or mitigate impacts to historic al resources, as required by local jurisdictions and state law.
As identified in Section 3.4.4, no cultural resources were identified at the project area during the SCIC records search, NAHC Sacred Lands File search, and the pedestrian survey. However, there is a moderate potential that buried cultural resources deposits may be encountered during excavation. To further ensure project development would not result in potential impacts to cultural resources, the project would implement MM -CR-1 thro ugh MM -CR-3 to ensure that potential impacts to archaeological resources pur suant to CEQA Guidelines Section 15064.5 would remain less than significant. It is expected that cultural resources studies would be prepared for all other cumulative projects to assess potential impacts, and that these projects would similarly avoid or mitigate impacts to cultural resources, as required by local jurisdictions and state law.
Similar to the project, the presence of human remains on cumulative project sites would typically remain unknown for cumulative projects until earthwork activities commence for project construction.
As identified in Section 3.4.4, the project area is not used as a cemetery and is not otherwise known to contain human remains, and the pedestrian field survey conducted for the project did not identify any human remains or find any indications that they would be expected to be found at the project area.
However, although unlikely, there is the possibility of human remains being discovered during ground disturbing activities at the project area. If remains are discovered during project construction activities, the project would be required to comply with Section 7050.5 of the California Health and Safety Code, and MM-CR-4 would be implemented to ensure that potential impacts to human remains would be less than significant. It is expected that all cumulative projects would similarly assess potential impacts to huma n remains , and that these cumulative projects would avoid or mitigate these impacts, as required by local jurisdictions and state law.
Because the project and those projects identified within the cumulative study area would be required to mitigate cultural resources impacts through the collection and curation of information, construction monitoring, and the preservation of the most important resources, cumulative cultural resources impacts would be less than significant.
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3.4.6 Mitigation Measures
Implementation of MM-CR-1 through MM-CR-3 would ensure that potential impacts to archaeological resources pursuant to CEQA Guidelines Section 15064.5 (Impact CR -1) would remain less than significant, as identified above in response to Threshold #2. Implementation of MM-CR-4 would ensure that potential impacts to human remains (Impact CR-2) would be less than significant, identified above in response to Threshold #3.
MM-CR-1 Pre-Excavation Agreement: Prior to the issuance of a Grading Permit, or ground disturbing activities, the Applicant/Owner shall enter into a Tribal Cultural Resources Treatment and Repatriation Agreement (Pre-Excavation Agreement) with a Traditionally and Culturally Affiliated Nati ve American Tribe (TCA Tribe), identified in consultation with the City. The purpose of the Pre -Excavation Agreement shall be to formalize protocols and procedures between the Applicant/Owner and the TCA Tribe for the protection, treatment, and repatriation of Native American human remains, funerary objects, cultural and/or religious landscapes, ceremonial items, traditional gathering areas, and other tribal cultural resources. Such resources may be located within and/or d iscovered during ground disturbing and/or construction activities for the project, including any additional culturally appropriate archaeological studies, excavations, geotechnical investigations, grading, preparation for wet and dry infrastructure, and ot her ground disturbing activities. Any project -specific Monitoring Plans and/or excavation plans prepared by the project archaeologist shall include the TCA Tribe requirements for protocols and protection of tribal cultural resources that were agreed to during the tribal consultation.
The landowner shall relinquish ownership of all non -burial related tribal cultural resources collected during construction monitoring and from any previous archaeological studies or excavations on the project site to the TCA Tribe for proper treatment and disposition per the Pre -Excavation Agreement, unless ordered to do otherwise by responsible a gency or court of competent jurisdiction. The requirement and timing of such release of ownership, and the recipient thereof, shall be reflected in the Pre -Excavation Agreement. If the TCA Tribe does not accept the return of the cultural resources, then the cultural resources will be subject to curation.
MM-CR-2 Construction Monitoring: Prior to the issuance of a Grading Permit or ground disturbing activities, the Applicant/Owner or Grading Contractor shall provide written documentation (either as signed letters, contracts, or emails) to the City ’s Planning Division stating that a Qualified Archaeologist and Traditionally and Culturally Affiliated Native American monitor (TCA Native American monitor) have been retained at the Applicant/Owner or Grading Contractor ’s expense to implement the construction
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monitoring program, as described in the Pre -Excavation Agreement . A monitor representing the San Pasqual Band of Mission Indians shall be provided the opportunity to monitor, should they choose to.
Native American monitoring shall include a monitor representing a TCA Tribe (Luiseño) and a monitor representing the San Pasqual Band of Mission Indians (if the San Pasqual Band elects to monitor). In the event that one or more TCA Tribe chooses not to enter into an agreement, or fails to respond to the offer, the City shall extend the opportunity for another TCA Ttribe to provide a monitor. In the event that more than one TCA Tribe requests to provide a TCA Native American monitor for activities subject to these measures, the City will allow for either: 1) up to one monitor from each consulting tribe to be present simultaneously; or 2) for the tribes to develop a rotating schedule that alternates monitoring between the tribes on a daily or weekly basis. The monitors shall be provided at least 72 hours ’ notice of the initiation of construction and be kept reasonably apprised of changes to the construction schedule. In the event that a monitor is not present at the scheduled time, work can continue without th e monitor present, as long as the notice was given and documented.
The Qualified Archaeologist and TCA Native American monitor shall be invited to attend all applicable pre -construction meetings with the General Contractor and/or associated subcontractors to present the construction monitoring program. The Qualified Arch aeologist and TCA Native American monitor shall be present on site during grubbing, grading, trenching, and/or other ground -disturbing activities that occur in areas of native soil or other permeable natural surfaces that have the potential to unearth any evidence of potential archaeological resources or tribal cultural resources. In areas of artificial paving, the Qualified Archaeologist and TCA Native American monitor shall be present on site during grubbing, grading, trenching, and/or other ground distur bing activities that have the potential to disturb more than six inches below the original pre -project ground surface to identify any evidence of potential archaeological or tribal cultural resources. If export of soil is planned, consultation with the affi liated Tribes will have to be initiated. No monitoring of fill material, existing or imported, will be required if the General Contractor or developer can provide documentation to the satisfaction of the City that all fill materials being utilized at the site are either: 1) from existing commerci al (previously permitted) sources of materials; or 2) are from private or other non-commercial sources that have been determined to be absent of tribal cultural resources by the Qualified Archaeologist and TCA Native American monitor.
The Qualified Archaeologist and TCA Native American monitor shall maintain ongoing collaborative coordination with one another during all ground disturbing activities. The
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requirement for the construction monitoring program shall be noted on all applicable construction documents, including demolition plans, grading plans, etc. The Applicant/Owner or Grading Contractor shall provide written notice to the Planning Division and the TCA Tribe, preferably through e-mail, of the start and end of all ground disturbing activities.
Prior to the release of any grading bonds, or prior to the issuance of any project Certificate of Occupancy, an archaeological monitoring report, which describes the results, analysis, and conclusions of the construction monitoring shall be submitted by the Qualified Archaeologist, along with any TCA Native American monitor ’s notes and comments received by the Qualified Archaeologist, to the Planning Division Manager for approval. Once approved, a final copy of the archaeological monitoring report shall be retained in a confidential City project file and may be released, as a formal condition of Assembly Bill (AB) 52 consultation, to Rincon Band of Luiseño Indians, San Luis Rey Band of Mission Indians, San Pasqual Band of Mission Indians, or any parties involved in the project specific monitoring or consultation process. A final copy of the report, with all confidential site records and appendices, will also be submitted to the South Coastal Information Center after approval by the City.
MM-CR-3 Unanticipated Discovery Procedures: Both the Qualified Archaeologist and the TCA Native American monitor may temporarily halt or divert ground disturbing activities if potential archaeological resources or tribal cultural resources are discovered during construction activities. Ground disturbing activities shall be temporarily directed away from the area of discovery for a reasonable amount of time to allow a determination of the resource ’s potential significance. Isolates and clearly non -significant archaeological resources (as determined by the Qualified Archaeologist, in consultation with the TCA Native America n monitor) will be minimally documented in the field. All unearthed archaeological resources or tribal cultural resources will be collected, temporarily stored in a secure location (or as otherwise agreed upon by the Qualified Archaeologist and the TCA Tri be), and repatriated according to the terms of the Pre-Excavation Agreement, unless ordered to do otherwise by responsible agency or court of competent jurisdiction.
If a determination is made that the archaeological resources or tribal cultural resources are considered potentially significant by the Qualified Archaeologist, the TCA Tribe, and the TCA Native American monitor, then the City and the TCA Tribe shall determine, in consultation with the Applicant/Owner and the Qualified Archaeologist, the culturally appropriate treatment of those resources.
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If the Qualified Archaeologist, the TCA Tribe, and the TCA Native American monitor cannot agree on the significance or mitigation for such resources, these issues will be presented to the Planning Division Manager for decision. The Planning Division Manager shall make a determination based upon the provisions of CEQA and California Public Resources Code Section 21083.2(b) with respect to archaeological resources and California Public Resources Section 21704 and 21084.3 with respect to tribal cultural resources, and shall take into account the religious beliefs, cultural beliefs, customs, and practices of the TCA Tribe.
All sacred sites, significant tribal cultural resources, and/or unique archaeological resources encountered within the project area shall be avoided and preserved as the preferred mitigation. If avoidance of the resource is determined to be infeasible by the City as the Lead Agency, then the City shall require additional culturally appropriate mitigation to address the negative impact to the resource, such as, but not limited to, the funding of an ethnographic study and/or a data recovery plan, as determin ed by the City in consultation with the Qualified Archaeologist and the TCA Tribe. The TCA Tribe shall be notified and consulted regarding the determination and implementation of culturally appropriate mitigation and the drafting and finalization of any ethnographic study and/or data recovery plan, and/or other culturally appropriate mitigation. Any archaeological isolates or other cultural materials that cannot be avoided or preserved in place as the preferred mitigation shall be temporarily stored in a secure location on site (or as otherwise agreed upon by the Qualified Archaeologist and TCA Tribe), and repatriated according to the terms of the Pre -Excavation Agreement, unless ordered to do otherwise by responsible agency or court of competent jurisdictio n. The removal of any artifacts from the project site will be inventoried with oversight by the TCA Native American monitor.
If a data recovery plan is authorized as indicated above and the TCA Tribe does not object, then an adequate artifact sample to address research avenues previously identified for sites in the area will be collected using professional archaeological collection methods. If the Qualified Archaeologist collects such resources, the TCA Native American monitor must be present during any testing or cataloging of those resources. Moreover, if the Qualified Archaeologist does not collect the cultural resources that are unearthed during the ground disturbing activities, the TCA Native American monitor may, at their discretion, collect said resources for later reburial or storage at a local curation facility, as described in the Pre-Excavation Agreement.
In the event that curation of archaeological resources or tribal cultural resources is required by a superseding regulatory agency, curation shall be conducted by an approved local facility within San Diego County and the curation shall be guided by
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California State Historical Resources Commission ’s Guidelines for the Curation of Archaeological Collections. The City shall provide the Applicant/Owner final curation language and guidance on the project grading plans prior to issuance of the grading permit, if applicable, during project construction. T he Applicant/Owner shall be responsible for all repatriation and curation costs and provide to the City written documentation from the TCA Tribe or the curation facility, whichever is most applicable, that the repatriation and/or curation have been completed.
MM-CR-4 Human Remains: As specified by California Health and Safety Code Section 7050.5, if human remains, or remains that are potentially human, are found on the project site during ground disturbing activities or during archaeological work, the person responsible for the excav ation, or his or her authorized representative, shall immediately notify the San Diego County Medical Examiner ’s Office by telephone. No further excavation or disturbance of the discovery or any nearby area reasonably suspected to overlie adjacent remains (as determined by the Qualified Archaeologist and/or the TCA Native American monitor) shall occur until the Medical Examiner has made the necessary findings as to origin and disposition pursuant to Public Resources Code 5097.98.
If such a discovery occurs, a temporary construction exclusion zone shall be established surrounding the area of the discovery so that the area would be protected (as determined by the Qualified Archaeologist and/or the TCA Native American monitor), and consultation and treatment could occur as prescribed by law. As further defined by State law, the Medical Examiner will determine within two working days of being notified if the remains are subject to his or her authority. If the Medical Examiner recognizes the remains to be Native American, and not under his or her jurisdiction, then he or she shall contact the Native American Heritage Commission by telephone within 24 hours. The Native American Heritage Commission will make a determination as to the Most Likely Descendent, who shall be afforded 48 hours from the time access is granted to the discovery site to make recommendations regarding culturally appropriate treatment.
If suspected Native American remains are discovered, the remains shall be kept in situ (in place) until after the Medical Examiner makes its determination and notifications, and until after the Most Likely Descendent is identified, at which time the archaeological examination of the remains shall only occur on site in the presence of the Most Likely Descendent. The specific locations of Native American burials and reburials will be proprietary and not disclosed to the general public. According to California Health and Safety Code, six or more human burials at one location constitute a cemetery (Section 8100), and disturbance of Native American cemeteries is a felony
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(Section 7052). In the event that the Applicant/Owner and the Most Likely Descendant are in disagreement regarding the disposition of the remains, State law will apply, and the mediation process will occur with the NAHC. In the event that mediation is not successful, the landowner shall rebury the remains at a location free from future disturbance (see Public Resources Code Section 5097.98[e] and 5097.94[k]).
3.4.7 Conclusion
Implementation of the project would not impact any identified archaeological resources, historical resources, or any known human remains interred outside a formal cemetery. However, based upon the analysis presented in Section 3.4.4, the potential exists for impacts to unknown cultural resources resulting from implementation of the project. However, there is potential that buried cultural resources deposits or human remains may be encountered during excavation. To further ensure project development would not result in potential impacts to cultural resources or human remains, the project would implement MM -CR-1 through MM -CR-4 to ensure that potential impacts to archaeological resources and human remains would be less than significant. Specifically, implementation of MM-CR- 1 through MM-CR-3 provide for the presence of archaeological and Native American monitors during ground disturbing activities that would be able to identify any previously unidentified cultural resources and to prevent inadvertent disturbance of any intact cultural deposits that may be present. Should any resources be identified, implementation of MM-CR-1 through MM-CR-3 would ensure proper handling and treatment of such resources by providing for a proper evaluation to determine whether additional archaeological work is necessary.
Potential impacts to human remains would be mitigated through implementation of MM-CR-4, which includes the requirement that any remains uncovered during ground disturbing activities shall not be further disturbed until the San Diego County Coroner has determined origins of the remains and final treatment has been agreed to with input of Native American Tribes as necessary. With incorporation of these mitigation measures, potential impacts to cultural resources associated with the project would remain less than significant.
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3.5 ENERGY
This section describes the existing setting of the project site with respect to energy use and conservation, identifies associated regulatory requirements, and evaluates potential impacts related to implementation of the Hughes Circuits Project (project).
Appendix G and Appendix F of the California Environmental Quality Act (CEQA) Guidelines requires that an environmental impact report (EIR) discusses the potential energy impacts of proposed projects, with particular emphasis on avoiding or reducing inefficient, wasteful, and unnecessary consumption of energy, to ensure that energy implications are considered in project-related decision-making processes.
As such, this section analyzes the energy impacts of the project. Specifically, this section summarizes the existing conditions in the project area, discusses the regulatory framework, and discloses estimated energy use during the construction and operational phases of the project. This analysis considers the electricity, natural gas, and transportation fuel (petroleum) demand of the project.
Information in this section is based on the project’s Air Quality and Greenhouse Gas Emissions Technical Report (October 2022), prepared by Dudek, which is included as Appendix B of this EIR.
Table 3.5-1 summarizes the project- and cumulative-level energy impacts, by threshold.
Table 3.5-1
Energy Summary of Impacts
Threshold of Significance
Project-Level
Impact
Cumulative-
Level Impact
Significance
Determination
#1 – Result in potentially significant environmental
impact due to wasteful, inefficient, or unnecessary
consumption of energy resources, during project
construction or operation.
Less than
Significant
Less than
Significant
Less than
Significant
#2 – Conflict with or obstruct a state or local plan
for renewable energy or energy efficiency.
Less than
Significant
Less than
Significant
Less than
Significant
3.5.1 Existing Conditions
The environmental setting for the project related to electricity, natural gas, and petroleum, including associated service providers, supply sources, and estimated consumption, is discussed below. In summary, in 2020 (the latest calendar year for which data is uniformly available for all three types of energy sources), California’s estimated annual energy use included the following:
• Approximately 250,175 gigawatt hours of electricity (EIA 2021a) • Approximately 21 billion therms of natural gas (EIA 2021b) • Approximately 22 billion gallons of petroleum (EIA 2022)
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Electricity
According to the U.S. Energy Information Administration, California used approximately 250,175 gigawatt hours of electricity in 2020 (EIA 2021a). Electricity usage in California for different land uses varies substantially by the types of uses in a building, type of construction materials used in a building, and the efficiency of all electricity-consuming devices within a building.
San Diego Gas & Electric (SDG&E) provides electric services to 3. 7 million customers through
1.49 million electric meters located in a 4,100 -square-mile service area that includes San Diego County and southern Orange County (SDG&E 2022). SDG&E is a subsidiary of Sempra Energy and would provide electricity to the project. SDG&E receives electric power from a variety of sources.
According to the California Energy Commission (CEC) 2021 California Renewable Portfolio Standard Annual Report, 39% of SDG&E’s power came from eligible renewable energy sources in 2020, including biomass/waste, geothermal, small hydroelectric, solar, and wind sources (CPUC 2021).
According to the CEC, SDG&E customers consumed approximately 17,445 million kilowatt-hours (kWh) of electricity in 2020 (CEC 2022a).
Natural Gas
The California Public Utilities Commission (CPUC) regulates natural gas utility service for approximately
10.8 million customers who receive natural gas from Pacific Gas & Electric, Southern California Gas (SoCalGas), SDG&E, Southwest Gas, and several smaller natural gas utilities. CPUC also regulates independent storage operators Lodi Gas Storage, Wild Goose Storage, Central Valley Storage, and Gill Ranch Storage (CPUC 2022). SDG&E provides natural gas service to the counties of San Diego and Orange and would provide natural gas to the project. SDG&E is a wholesale customer of SoCalGas and currently receives all of its natural gas from the SoCalGas system (CPUC 2022).
CPUC regulates California natural gas rates and natural gas services, including in-state transportation over transmission and distribution pipeline systems, storage, procurement, metering, and billing. Most of the natural gas used in California comes from out-of-state natural gas basins. Biogas (i.e., from wastewater treatment facilities or dairy farms) is just beginning to be delivered into the gas utility pipeline systems, and the State has been encouraging its development (CPUC 2022).
Most of the natural gas transported through interstate pipelines, as well as some California-produced natural gas, is delivered through the Pacific Gas & Electric and SoCalGas intrastate natural gas transmission pipeline systems (commonly referred to as California’s “backbone” natural gas pipeline system). Natural gas on the backbone pipeline system typically is then delivered into local transmission and distribution pipeline systems or to natural gas storage fields. CPUC has regulatory jurisdiction over 100,000 miles of utility‐owned natural gas pipelines (CPUC 2022).
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According to the CEC, SDG&E customers consumed approximately 505 million therms of natural gas in 2020 (CEC 2022b).
Petroleum
According to the U.S. Energy Information Administration , California used approximately 524 million barrels of petroleum in 2020, with the majority (433 million barrels) used for the transportation sector (EIA 2022). This total annual consumption equates to a daily use of approximately 1.4 million barrels of petroleum. There are 42 U.S. gallons in a barrel, so California consumes approximately 60 million gallons of petroleum per day, adding up to an annual consumption of 22 billion gallons of petroleum.
Petroleum usage in California includes petroleum products such as motor gasoline, distillate fuel, liquefied petroleum gases, and jet fuel. California has implemented policies to improve vehicle efficiency and to support use of alternative transportation, whic h are described in Section 3. 5.2, Regulatory Setting. As such, the CEC anticipates an overall decrease of gasoline demand in the state over the next decade.
According to the California Air Resources Board’s (CARB) Emission Factor (EMFAC) Web Database, San Diego County on-road transportation sources are projected to consume approximately 1.5 billion gallons of petroleum in 2025 (CARB 2022).
3.5.2 Regulatory Setting
Federal, state, and local agencies regulate energy use and consumption through various means and programs. On the federal level, the U.S. Department of Transportation, the U.S. Department of Energy, and the U.S. Environmental Protection Agency (EPA) are three federal agencies with substantial influence over energy policies and programs. On the state level, CPUC and CEC are two agencies with authority over different aspects of energy. Relevant federal, state, and local energy-related regulations are summarized below. This information helps to place the impact analysis within its proper regulatory context.
Federal
Federal Energy Policy and Conservation Act
In 1975, Congress enacted the Federal Energy Policy and Conservation Act, which established the first fuel economy standards for on -road motor vehicles in the United States. Pursuant to the act, the National Highway Traffic Safety Administration is respons ible for establishing additional vehicle standards. In 2012, new fuel economy standards for passenger cars and light trucks were approved for model years 2017 through 2021 (77 FR 62624 –63200). Fuel economy is determined based on each manufacturer’s average fuel economy for the fleet of vehicles available for sale in the United States.
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Intermodal Surface Transportation Efficiency Act of 1991 The Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA) promoted the development of intermodal transportation systems to maximize mobility and address national and local interests in air quality and energy. ISTEA contained factors that metropolitan planning organizations were to address in developing transportation plans and programs, including some energy‐related factors. To meet the new ISTEA requirements, metropolitan planning organizations adopted policies defining the social, economic, energy, and environmental values guiding transportation decisions.
Transportation Equity Act for the 21st Century
The Transportation Equity Act for the 21st Century was signed into law in 1998 and builds on the initiatives established in the ISTEA legislation, discussed above. The act authorizes highway, highway safety, transit, and other efficient surface transportat ion programs. The act continues the program structure established for highways and transit under ISTEA, such as flexibility in the use of funds, emphasis on measures to improve the environment, and focus on a strong planning process as the foundation of tr ansportation decisions. The act also provides for investment in research and its application to maximize the performance of the transportation system through, for example, deployment of intelligent transportation systems to help improve operations and mana gement of transportation systems and vehicle safety.
Energy Independence and Security Act of 2007
On December 19, 2007, the Energy Independence and Security Act of 2007 (EISA) was signed into law. In addition to setting increased fuel efficiency standards for motor vehicles, the EISA includes the following other provisions related to energy efficiency:
• Renewable Fuel Standard (RFS) (Section 202)
• Appliance and Lighting Efficiency Standards (Sections 301–325) • Building Energy Efficiency (Sections 411–441)
This federal legislation requires ever -increasing levels of renewable fuels (the RFS) to replace petroleum (EPA 2017). The EPA is responsible for developing and implementing regulations to ensure that transportation fuel sold in the United States contains a minimum volume of renewable fuel. The RFS program regulations were developed in collaboration with refiners, renewable fuel producers, and many other stakeholders.
The RFS program was created under the Energy Policy Act of 2005 and established the first renewable fuel volume mandate in the United States. As required under the act, the original RFS program (RFS1) required 7.5 billion gallons of renewable fuel to be blended into gasoline by 2012. Under the EISA, the RFS program was expanded in several key ways that lay the foundation for achieving significant
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reductions in greenhouse gas ( GHG) emissions from the use of renewable fuels, reducing imported petroleum, and encouraging the development and expansion of the renewable fuels sector in the United States. The updated program is referred to as “RFS2” and includes the following:
• EISA expanded the RFS program to include diesel, in addition to gasoline. • EISA increased the volume of renewable fuel required to be blended into transportation fuel from 9 billion gallons in 2008 to 36 billion gallons by 2022. • EISA established new categories of renewable fuel, and set separate volume requirements for each one.
• EISA required the EPA to apply lifecycle GHG performance threshold standards to ensure that each category of renewable fuel emits fewer GHGs than the petroleum fuel it replaces.
Additional provisions of the EISA address energy savings in government and public institutions, research for alternative energy, additional research in carbon capture, international energy programs, and the creation of “green” jobs.
State
The discussion below focuses primarily on those policies, regulations, and laws that directly pertain to energy-related resources. Refer to Section 3.7, Greenhouse Gas Emissions, of this EIR, which addresses various policies, regulations, and laws targeted to the reduction of GHG emissions that are expected to achieve co -benefits in the form of reduced demand for energy -related resources and enhanced efficiencies in the consumption of energy-related resources.
Warren-Alquist Act
The California Legislature passed the Warren-Alquist Act in 1974. The Warren-Alquist Act created the CEC. The legislation also incorporated the following three key provisions designed to address the demand side of the energy equation:
• It directed the CEC to formulate and adopt the nation’s first energy conservation standards for both buildings constructed and appliances sold in California. • The act removed the responsibility of electricity demand forecasting from the utilities, which had a financial interest in high demand projections, and transferred it to a more impartial CEC. • The CEC was directed to embark on an ambitious research and development program, with a particular focus on fostering what were characterized as non-conventional energy sources.
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State of California Energy Action Plan
The CEC and CPUC approved the first State of California Energy Action Plan in 2003. The plan established shared goals and specific actions to ensure that adequate, reliable, and reasonably priced electrical power and natural gas supplies are provided, and identified policies, strategies, and actions that are cost-effective and environmentally sound for California's consumers and taxpayers. In 2005, a second Energy Action Plan was adopted by the CEC and CPUC to reflect various policy changes and actions of the prior 2 years.
At the beginning of 2008, the CEC and CPUC determined that it was not necessary or productive to prepare a new energy action plan. This determination was based in part on a finding that the state’s energy policies have been significantly influenced by the passage of Assembly Bill (AB) 32, the California Global Warming Solutions Act of 2006 (discussed below). Rather than produce a new energy action plan, the CEC and CPUC prepared an “update” that examines the state’s ongoing actions in the context of global climate change.
Senate Bills 1078, 107, X1-2, 350, 100, and 1020
Senate Bill (SB) 1078 (2002) established the California Renewables Portfolio Standard Program and required that a retail seller of electricity purchase a specified minimum percentage of electricity generated by eligible renewable energy resources as defined in any given year, culminating in a 20% standard by December 31, 2017. These retail sellers include electrical corporations, community choice aggregators, and electric service providers. The bill relatedly required the CEC to certify eligible renewable energy resources, design and implement an accounting system to verify compliance with the Renewables Portfolio Standard by retail sellers, and allocate and award supplemental energy payments to cover above-market costs of renewable energy.
SB 107 (2006) accelerated the Renewables Portfolio Standard established by SB 1078 by requiring that 20% of electricity retail sales be served by renewable energy resources by 2010 (not 2017).
Additionally, SB X1 -2 (2011) requires all California utilities to generate 33% of their electricity from eligible renewable energy resources by 2020. Specifically, SB X1 -2 sets a three -stage compliance period: by December 31, 2013, 20% shall come from renewables; by December 31, 2016, 25% shall come from renewables; and by December 31, 2020, 33% shall come from renewables.
SB 350 (2015) requires retail seller and publicly owned utilities to procure 50% of their electricity from eligible renewable energy resources by 2030, with interim goals of 40% by 2024 and 45% by 2027.
SB 100 (2018) accelerated and expanded the standards set forth in SB 350 by establishing that 44% of the total electricity sold to retail customers in California per year by December 31, 2024, 52% by December 31, 2027, and 60% by December 31, 2030 be secur ed from qualifying renewable energy sources. SB 100 also states that it is the policy of the state that eligible renewable energy resources and
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zero-carbon resources supply 100% of the retail sales of electricity to California. This bill requires that the achievement of 100% zero -carbon electricity resources does not increase the carbon emissions elsewhere in the western grid and that the achievement not be achieved through resource shuffling.
SB 1020 (September 2022) revises the standards from SB 100, requiring the following percentage of retail sales of electricity to California end -use customers come from eligible renewable energy resources and zero-carbon resources:
• 90% by December 31, 2035
• 95% by December 31, 2040
• 100% by December 31, 2045
Consequently, utility energy generation from non -renewable resources is expected to be reduced based on implementation of greater Renewables Portfolio Standard requirements in future years .
Therefore, any project’s reliance on non-renewable energy sources would also be reduced.
Assembly Bill 1007 (2005)
AB 1007 (2005) required the CEC to prepare a statewide plan to increase the use of alternative fuels in California (State Alternative Fuels Plan). The CEC prepared the plan in partnership with the CARB and in consultation with the other state, federal, and local agencies. The plan assessed various alternative fuels and developed fuel portfolios to meet California’s goals to reduce petroleum consumption, increase alternative fuels use, reduce GHG emissions, and increase in-state production of biofuels without causing a significant degradation of public health and environmental quality.
Assembly Bill 32 and Senate Bill 32
In 2006, the Legislature enacted AB 32, the California Global Warming Solutions Act of 2006. AB 32 requires California to reduce its GHG emissions to 1990 levels by 2020. In 2016, the Legislature enacted SB 32, which extended the horizon year of the state’s c odified GHG reduction planning targets from 2020 to 2030, requiring California to reduce its GHG emissions to 40% below 1990 levels by 2030. In accordance with AB 32 and SB 32, CARB prepares scoping plans to guide the development of statewide policies and regulations for the reduction of GHG emissions. Many of the policy and regulatory concepts identified in the scoping plans focused on increasing energy efficiencies and the use of renewable resources and reducing the consumption of petroleum -based fuels (s uch as gasoline and diesel). As such, the state’s GHG emissions reduction planning framework creates co -benefits for energy -related resources. Additional information on AB 32 and SB 32 is provided in Section 3.7 of this EIR.
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California Building Standards
Title 24 of the California Code of Regulations was established in 1978 and serves to enhance and regulate California’s building standards. While not initially promulgated to reduce GHG emissions, Part 6 of Title 24 specifically established Building Energy Efficiency Standards that are designed to ensure new and existing buildings in California achieve energy efficiency and preserve outdoor and indoor environmental quality. These energy efficiency standa rds are reviewed every few years by the Building Standards Commission and the CEC (and revised if necessary) (California Public Resources Code Section 25402[b][1]). The regulations receive input from members of industry, as well as the public, with the goal of “reducing of wasteful, uneconomic, inefficient, or unnecessary consumption of energy” (California Public Resources Code Section 25402). These regulations are carefully scrutinized and analyzed for technological and economic feasibility (California Public Resources Code Section 25402[d]) and cost effective ness (California Public Resources Code Sections 25402[b][2] and [b][3]). As a result, these standards save energy, increase electricity supply reliability, increase indoor comfort, avoid the need to construct new power plants, and help preserve the environment. The 2022 Title 24 standards are the currently applicable building energy efficiency standards, and became effective on January 1, 2023. The 2022 Energy Code focuses on four key areas in newly constructed homes and businesses:
• Encouraging electric heat pump technology for space and water heating, which consumes less energy and produces fewer emissions than gas-powered units. • Establishing electric -ready requirements for single -family homes to position owners to use cleaner electric heating, cooking, and electric vehicle (EV) charging options whenever they choose to adopt those technologies. • Expanding solar photovoltaic (PV) system and battery storage standards to make clean energy available onsite and complement the state’s progress toward a 100% clean electricity grid.
• Strengthening ventilation standards to improve indoor air quality.
In addition to the CEC’s efforts, in 2008, the California Building Standards Commission adopted the nation’s first green building standards. The California Green Building Standards Code (Part 11 of Title 24) is commonly referred to as CALGreen, and establi shes minimum mandatory standards and voluntary standards pertaining to the planning and design of sustainable site development, energy efficiency (in excess of the California Energy Code requirements), water conservation, material conservation, and interio r air quality. The CALGreen standards took effect in January 2011 and instituted mandatory minimum environmental performance standards for all ground -up, new construction of commercial, low -rise residential and state -owned buildings and schools and hospitals. The 2022 CALGreen standards, which are the current standards, became effective January 1, 2023. For nonresidential projects, some of the key mandatory CALGreen standards involve requirements related to bicycle parking, requirements for EV capable spaces and EV charging
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stations, shade trees, water conserving plumbing fixtures and fittings, outdoor potable water use in landscaped areas, construction waste management, excavated soil and land clearing debris, and commissioning (24 CCR Part 11).
Integrated Energy Policy Report
The CEC is responsible for preparing integrated energy policy reports, which identify emerging trends related to energy supply, demand, conservation, public health and safety, and maintenance of a healthy economy. The latest Integrated Energy Policy Report was released in February 2022 and addressed a variety of issues, including, but not limited to, implementation of SB 350, electricity resource/supply plans, electricity and natural gas demand forecast, natural gas outlook, transportation energy demand for ecasts, doubling energy efficiency savings, integrated resource planning, climate adaptation and resiliency, renewable gas, distributed energy resources, strategic transmission investment plan, and existing power plant reliability issues (CEC 2021).
State Vehicle Standards
In response to the transportation sector accounting for more than half of California’s carbon dioxide (CO2) emissions, AB 1493 was enacted in 2002. AB 1493 required CARB to set GHG emissions standards for passenger vehicles, light-duty trucks, and other vehicles determined by the state board to be vehicles whose primary use is noncommercial personal transporta tion in the state. The bill required that CARB set GHG emissions standards for motor vehicles manufactured in 2009 and all subsequent model years. The 2009–2012 standards resulted in a reduction in approximately 22% of GHG emissions compared to emissions from the 2002 fleet, and the 2013–2016 standards resulted in a reduction of approximately 30% compared to the 2002 fleet.
In 2019, the EPA and National Highway Traffic Safety Administration published the Safer Affordable Fuel-Efficient Vehicles Rule Part One: One National Program (SAFE -1) (84 FR 51310), which revoked California’s authority to set its own GHG emissions standards and set zero -emissions vehicle (ZEV) mandates in California. In March 2020, Part Two was issued which set CO 2 emissions standards and corporate average fuel economy standards for passenger vehicles and light -duty trucks for model years 2021 through 2026 . In March 2022, EPA reinstated California’s authority under the Clean Air Act to implement its own GHG emission standards and ZEV sales mandate. EPA’s action concludes its reconsideration of the 2019 SAFE -1 rule by finding that the actions taken under the previous administration as a part of SAFE-1 were decided in error and are now entirely rescinded.
Advanced Clean Cars Program
The Advanced Clean Cars (ACC) I program (January 2012) is an emissions -control program for model years 2015 through 2025. The program combines the control of smog - and soot-causing pollutants and GHG emissions into a single coordinated package of regulatio ns: the low-emissions vehicle regulation for criteria air pollutant and GHG emissions and a technology forcing regulation for ZEV that
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contributes to both types of emission reductions (CARB 2021a). The package includes elements to reduce smog-forming pollution, reduce GHG emissions, promote clean cars, and provide the fuels for clean cars. To improve air quality, CARB has implemented new emission standards to reduce smog - forming emissions beginning with 2015 model year vehicles. It is estimated that in 2025 cars will emit 75% less smog-forming pollution than the average new car sold in 2015. The ZEV program will act as the focused technolo gy of the ACC I program by requiring manufacturers to produce increasing numbers of ZEVs and plug-in hybrid EVs in the 2018 to 2025 model years.
The ACC II program is currently in development to establish the next set of low-emissions vehicle and ZEV requirements for model years after 2025 to contribute to meeting federal ambient air quality ozone standards and California’s carbon neutrality standards (CARB 2021a). The main objectives of ACC II are as follows:
1. Maximize criteria and GHG emission reductions through increased stringency and real-world reductions.
2. Accelerate the transition to ZEVs through both increased stringency of requirements and associated actions to support wide-scale adoption and use.
The ACC II rulemaking package was adopted by CARB on August 25, 2022.
Executive Order N-79-20
Executive Order N-79-20 (2020) sets the goal for the State that 100 % of in -state sales of new passenger cars and trucks will be zero-emission by 2035. Executive Order N-79-20 also sets goals for transition to 100% zero emission all medium- and heavy-duty vehicles by 2045, zero emission drayage trucks by 2035, and zero emission off-road vehicles and equipment by 2035, where feasible. Among other directives to further this executive order, for passenger cars and truc ks, the Governor directed CARB to develop and propose regulations requiring increasing volumes of new zero-emission vehicles sold in the State towards the target of 100% of in-state sales by 2035. The Governor also directed the Governor’s Office of Business and Economic Development to develop a Zero-Emissions Vehicle Market Development Strategy, which was completed in February 2021. The executive order also directs updates and assessments to ensure zero-emission vehicle infrastructure is in place to support the levels of electric vehicle adoption required by the order.
Advanced Clean Trucks Regulation
The Advanced Clean Trucks Regulation was also approved by CARB in 2020. The purpose of the Advanced Clean Trucks Regulation is to accelerate the market for zero -emission vehicles in the medium- and heavy-duty truck sector and to reduce air pollutant emissions generated from on -road
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mobile sources (CARB 2021b). The regulation has two components including (1) a manufacturer sales requirement and (2) a reporting requirement:
1. Zero-emission truck sales: Manufacturers who certify Class 2b -8 chassis or complete vehicles with combustion engines will be required to sell zero -emission trucks as an increasing percentage of their annual California sales from 2024 to 2035. By 2035, zero - emission truck/chassis sales would need to be 55% of Class 2b–3 truck sales, 75% of Class 4-8 straight truck sales, and 40% of truck tractor sales.
2. Company and fleet reporting: Large employers including retailers, manufacturers, brokers and others will be required to report information about shipments and shuttle services. Fleet owners, with 50 or more trucks, will be required to report about their ex isting fleet operations. This information will help identify future strategies to ensure that fleets purchase available zero-emission trucks and place them in service where suitable to meet their needs.
Sustainable Communities Strategy
The Sustainable Communities and Climate Protection Act of 2008, or SB 375, coordinates land use planning, regional transportation plans, and funding priorities to help California meet its GHG emissions reduction mandates. As codified in California Governme nt Code, Section 65080, SB 375 requires metropolitan planning organizations (San Diego Association of Governments) to include a sustainable communities strategy in its regional transportation plan. The main focus of the sustainable communities strategy is to plan for growth in a fashion that will ultimately reduce GHG emissions, but the strategy is also a part of a bigger effort to address other development issues within the general vicinity, including transit and vehicle-miles traveled ( VMT), which influence the consumption of petroleum-based fuels.
Local
San Diego Association of Governments Regional Plan
The San Diego Association of Governments 2021 Regional Plan provides a long-term blueprint for the San Diego region that seeks to meet regulatory requirements, address traffic congestion, and create equal access to jobs, education, healthcare, and other community resources (SANDAG 2021). The plan is the result of years of planning, data analysis, and community engagement to reimagine the San Diego region with a transformative transportation system, a sustainable pattern of growth and development, and innovative demand and management strategies.
The 2021 Regional Plan includes a Sustainable Communities Strategy, as required by California SB 375 (Steinberg, 2008) (SB 375), for the San Diego region. This Sustainable Communities Strategy describes coordinated transportation and land use planning that exceeds the state’s target for reducing per capita GHG emissions set by the California Air Resources Board. The state -mandated
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target is a 19% reduction—compared with 2005—in per-capita GHG emissions from cars and light-duty trucks by 2035. The 2021 Regional Plan achieves a 20% reduction by then.
The 2021 Regional Plan also puts forth a forecasted development pattern that is driven by regional goals for sustainability, mobility, housing affordability, and economic prosperity.
City of San Marcos General Plan
The City of San Marcos (City) General Plan (City of San Marcos 2012) includes various policies related to reducing GHG emissions and the co -benefit of reducing energy consumption . The project’s consistency with the City’s General Plan is provided in Section 3.10 , Land Use and Planning, of this EIR. Applicable policies include the following:
Land Use and Community Design Element
• Policy LU -2.1: Promote compact development patterns that reduce air pollution and automobile dependence and facilitate walking, bicycling, and transit use. • Policy LU -2.3: Require the incorporation of green building practices, technologies, and strategies into development projects per code standards. • Policy LU -2.5: Promote landscaping (e.g., native, drought tolerant plants) that minimizes demands on water supply.
• Policy LU-3.1: Require that new development and redevelopment incorporate connections and reduce barriers between neighborhoods, transit corridors, and activity centers within the City.
Conservation and Open Space Element
• Policy COS-4.5: Encourage energy conservation and the use of alternative energy sources within the community.
• Policy COS-4.6: Promote efficient use of energy and conservation of available resources in the design, construction, maintenance and operation of public and private facilities, infrastructure and equipment.
• Policy COS-4.8: Encourage and support the generation, transmission and use of renewable energy.
City of San Marcos Climate Action Plan
The City adopted its Climate Action Plan (CAP) on December 8, 2020 (City of San Marcos 2020). The CAP acts as a roadmap to address challenges of climate change within the City. The CAP builds on the efforts and strategies identified in the City’s 2013 CAP and establishes GHG emission reduction targets and identifies achievable, locally based actions to reduce GHG emissions from municipal and community activities. The CAP includes a baseline GHG emissions inventory for 2012, GHG emissions
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forecasts for 2020 and 2030, local GHG emissions reduction strategies and measures to help the City achieve the 2030 target, climate adaptation measures for the City, and implementation and monitoring mechanisms to ensure the City’s measures and targets are achieved. The CAP established GHG emissions reduction goals of 4% below 2012 levels by 2020 and 42% below 2012 levels by 2030 (City of San Marcos 2020). The City has included energy reducing measures into its Climate Action Plan Consistency Review Checklist to include electric vehicle charging stations, bicycle infrastructure, transportation demand management, reduced parking, electric or solar water heaters, photovoltaic systems, landscaping water use, and urban tree canopy.
3.5.3 Thresholds of Significance
The significance criteria used to evaluate the project’s impact on energy are based on Appendix G of the CEQA Guidelines (14 CCR 15000 et seq.). According to Appendix G, a significant impact would occur if development of the project would do any of the following:
• Threshold #1: Result in potentially significant environmental impact due to wasteful, inefficient, or unnecessary consumption of energy resources, during project construction or operation. • Threshold #2: Conflict with or obstruct a state or local plan for renewable energy or energy efficiency.
3.5.4 Project Impact Analysis
Threshold #1: Would the project result in potentially significant environmental impact due to wasteful, inefficient, or unnecessary consumption of energy resources, during project construction or operation?
Electricity
Construction Use
Temporary electric power for as-necessary lighting and electronic equipment (such as computers inside temporary construction trailers and heating, ventilation, and air conditioning) would be provided by SDG&E. The amount of electricity used during project construction would be minimal because typical demand stems from the use of electronic equipment, in addition to electrically-powered hand tools.
As the electricity used for construction activities would be temporary and minimal, impacts related to electricity consumption during project construction are determined to be less than significant.
Operational Use
The operation of the project buildout would require electricity for multiple purposes, including cooling, lighting, appliances, and various equipment. Additionally, the supply, conveyance, treatment, and distribution of water would indirectly result in electricity usage. Electricity consumption associated with project operation is based on the California Emissions Estimator Model (CalEEMod) outputs presented in Appendix B.
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CalEEMod default values for energy consumption for each land use were applied for the project analysis. The energy use from non -residential land uses is calculated in CalEEMod based on the California Commercial End -Use Survey database. Energy use in buildings (both natural gas and electricity) is divided by the program into end use categories subj ect to Title 24 requirements (end uses associated with the building envelope, such as the heating, ventilation, and air conditioning system; water heating system; and integrated lighting) and those not subject to Title 24 requirements (such as appliances, electronics, and miscellaneous “plug-in” uses).
According to these estimations, the project would consume approximately 488,180 kWh per year during operation (Appendix B). The project would also implement applicable City’s CAP Consistency Checklist measure s that would reduce operational electricity consumption, including PDF -GHG-1 (install a minimum of 9,700 square feet of PV panels). Based on the project location, this area of PV panels would produce approximately 226,347 kWh of energy per year (NREL 2022). With incorporation of PDF -GHG-1, the project’s electricity demand would be approximately 261,832 kWh per year. For context, SDG&E customers consumed approximately 17,445 million kWh of electricity in 2020 (CEC 2022a) .
In summary, although electricity consumption would increase at the project site due to project implementation, the project would be required to comply with the Title 24 and the City’s CAP Consistency Checklist by implementing energy -efficiency measures. The addition of solar PV also supports the City General Plan Policy COS-4.8. Furthermore, the project will be subject to the Title 24 building code that is adopted at the time building permits are obtained and thus may be subject to a more stringent energy standard than what was assumed herein, and the additional electricity demand for the project would not be unusual or wasteful as compared to overall local and regional demand for energy resources. For these reasons, electricity consumption of the project would not be considered inefficient, wasteful, or unnecessary, and impacts would be less than significant.
Natural Gas
Construction Use
Natural gas is not anticipated to be required during construction of the project. Fuels used for construction would primarily consist of diesel and gasoline, which are discussed under the subsection “Petroleum.” Any minor amounts of natural gas that may be consumed as a result of construction would be temporary and negligible and would not have an adverse effect on the environment ; therefore, impacts are determined to be less than significant.
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Operational Use
The operation would require natural gas for various purposes, including water heating and natural gas appliances. Natural gas consumption associated with operation is based on the CalEEMod outputs in Appendix B.
CalEEMod default values for energy consumption were applied for the project analysis. The energy use from non-residential land uses is calculated in CalEEMod based on the California Commercial End-Use Survey database. The 2019 Title 24 standards, became effective on January 1, 2020, were accounted for in the analysis . According to these estimations, the project would consume approximately 1,118,553 kilo-British Thermal Units (kBtu) per year, including operation of the forklift . For context, SDG&E customers consumed approximately 505 million therms, which equates to about 50.5 billion kBtu of natural gas in 2020 (CEC 2022b).
As previously discussed, the project would be subject to statewide mandatory energy requirements as outlined in Title 24, Part 6, of the California Code of Regulations. Prior to building permit application, the applicant would ensure that project plans would meet Title 24 requirements applicable at that time, as required by state regulations through their plan review process, and the additional natural gas demand for the project would not be unusual or wasteful as compared to other warehouses and the overall local and regional demand for energy resources . For these reasons, the natural gas consumption of the project would not be considered inefficient or wasteful, and impacts would be less than significant.
Petroleum
Construction Use
The primary energy consumed during construction would be associated with petroleum usage.
Potential impacts were assessed for off-road equipment and on-road vehicle trips during construction, as provided by the CalEEMod outputs (see Appendix B). Fuel consumption from construction equipment and vehicle trips was estimated by converting the total CO 2 emissions anticipated to be generated by the construction of the project to gallons using conversion factors for CO 2 to gallons of gasoline or diesel. The conversion factor for gasoline is 8.78 kilograms per metric ton CO2 per gallon, and the conversion factor for diesel is 10.21 kilograms per metric ton CO2 per gallon (The Climate Registry 2021). Heavy -duty construction equipment associated with construction activities, vendor trucks, and haul trucks are assumed to use diesel fuel. Worker vehicles are assumed to be gasoline fueled. All details for construction criteria air pollutant emissions modeling discussed in Appendix B are also applicable for the estimation of construction-related energy consumption.
The estimated diesel fuel usage from construction equipment, haul trucks, and vendor trucks, as well as estimated gasoline fuel usage from worker vehicles is shown in Table 3.5-2.
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Table 3.5-2
Project Construction Petroleum Demand
Construction
Off-Road
Equipment
(diesel) Haul Trucks (diesel)
Vendor Trucks
(diesel)
Worker Vehicles
(gasoline)
Gallons
Total 24,111.43 6,245.39 4,292.25 4,167.28
Total Petroleum Consumed for Project Construction 38,816.35 Notes: See Appendix B for details.
As shown in Table 3. 5-2, the project is estimated to consume approximately 38,316 gallons of petroleum during the construction phase. For context, in 2020, California consumed about 22 billion gallons of oil (EIA 2022). Notably, the project will be subject to the CARB’s In -Use Off-Road Diesel Vehicle Regulation that applies to certain off -road diesel engines, vehicles, or equipment greater than 25 horsepower. The regulation: (1) imposes limits on idling, requires a written idling policy, and requires a disc losure when selling vehicles, (2) requires all vehicles to be reported to CARB (using the Diesel Off -Road Online Reporting System) and labeled, (3) restricts the adding of older vehicles into fleets starting on January 1, 2014, and (4) requires fleets to r educe their emissions by retiring, replacing, or repowering older engines, or installing Verified Diesel Emission Control Strategies (i.e., exhaust retrofits). The fleet must either show that its fleet average index was less than or equal to the calculated fleet average target rate, or that the fleet has met the Best Achievable Control Technology requirements.
Overall, while construction activities would consume petroleum -based fuels, consumption of such resources would be temporary and would cease upon the completion of construction. Further, the petroleum consumed related to construction would be typical of construction projects of similar types and sizes and would not necessitate new petroleum resources beyond what are typically consumed in California. Therefore, because petroleum use during project construction would be temporary and minimal and would not be wasteful or inefficient, impacts are determined to be less than significant.
Operational Use
During operations, the majority of fuel consumption resulting from the project would involve the use of motor vehicles traveling to and from the project site. Petroleum fuel consumption associated with motor vehicles is a function of VMT as a result of project operation. The annual VMT attributable to the project is expected to be 1,519,046 VMT (Appendix B). Fuel estimates for the project are provided in Table 3.5-3.
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Table 3.5-3
Mobile Source Fuel Consumption – Operation
Fuel Vehicle MT CO2 Kilograms CO2 per Gallon Gallons
Gasoline 425.25 8.78 48,433.57
Diesel 5.85 10.21 572.68
Total 49,006.25
Sources: Appendix B (mobile source CO2); The Climate Registry 2021 (kg CO2/gallon).
CO2 = carbon dioxide; MT = metric ton
As depicted in Table 3.5-3, the project would consume approximately 49,006 gallons of petroleum per year during operation. For context, San Diego County on-road transportation sources are projected to consume approximately 1.5 billion gallons of petroleum in 2025 (CARB 2022), which is the first full year of project operations.
Over the lifetime of the project, the fuel efficiency of the vehicles being used by the employees and trucks for the project is expected to increase. As such, the amount of petroleum consumed as a result of vehicular trips to and from the project site during operation would decrease over time. There are numerous regulations in place that require and encourage increased fuel efficiency and EV use. For example, CARB has adopted the Advanced Clean Cars and Advanced Clean Trucks programs to accelerate the market for zero-emission vehicles in both the passenger car and medium/heavy -duty truck sectors. As such, operation of the project is expected to use decreasing amounts of petroleum over time, due to advances in fuel economy.
In summary, although the project would increase petroleum use during operation, the use would be a small fraction of the Countywide use and diminish over time due to efficiency increases. The additional fuel demand for the project would not be unusual or wasteful as compared to other warehouses and the overall local and regional demand for petroleum resources. Given these considerations, petroleum consumption associated with the project would not result in a potentially significant environmental impact due to wasteful, inefficient, or unnecessary consumption of energy resources, and impacts would be less than significant.
Renewable Energy Potential
As part of the project’s design process, the project applicant considered how the project could potentially increase its reliance on renewable energy sources to meet the project’s energy demand.
Renewable energy sources that were considered for their potential to be used to power the project, consistent with the CEC’s definition of eligible renewables, include biomass, geothermal, solar, wind, and small hydroelectric facilities.
Given the project’s location in an urban area and the nature of the project (i.e., a light industrial/ warehouse project ), there are considerable site constraints including limited land availability,
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incompatibility with onsite and surrounding land uses for large scale power generation facilities, unknown interconnection feasibility, compatibility with utility provider systems, and no known water or geothermal resources to harness, that would eliminate the potential for biomass, geothermal, and hydroelectric renewable energy to be installed on site.
Regarding wind power, due to the urban nature of the site and surrounding land uses, wind turbines are generally not feasible as it represents an incompatible use. Specifically, a general rule of thumb is to install a wind turbine on a tower with the bottom of the rotor blades at least 30 feet above anything within a 500 -foot horizontal radius and to be sited upwind of buildings and trees (APA 2011 ; NREL 2015), which the project site cannot accommodate.
Regarding solar power, the project does include solar power, which at a minimum, will include 9,700 square-feet of PV panels. The addition of solar PV is consistent with the City’s CAP and also supports the City’s General Plan Policies, such as Policy COS -4.8. While the project does not propose battery storage at the time, the project does not preclude installation of battery storage in the future if determined to be a feasible and compatible land use of the site.
In summary, the project includes the onsite renewable energy source (i.e., solar) that was determined to be feasible for the site and does not include the onsite renewable energy sources that were determined to be infeasible.
Summary
As explained above, the project would use renewable energy onsite as determined to be feasible and would not result in wasteful, inefficient, or unnecessary consumption of energy resources, including electricity, natural gas, or petroleum during project construction or operation. Impacts would be less than significant.
Threshold #2: Would the project conflict with or obstruct a state or local plan for renewable energy or energy efficiency?
The project would be subject to and would comply with, at a minimum, the California Building Energy Efficiency Standards (24 CCR, Part 6). Part 6 of Title 24 establishes energy efficiency standards for residential and non-residential buildings constructed in California in order to reduce energy demand and consumption. The project would also be subject to Part 11 of Title 24, also known as the CalGreen building standards. These were adopted into the City’s building design criteria. Furthermore, the project would be consistent with the City’s CAP Consistency Checklist measures , such as through its implementation of EV charging stations and PV panels, which would further reduce operational energy use. The project would be built and operated in accordance with all existing, applicable regulations at the time of construction. For these reasons stated, the project would result in a less than significant impact associated with the potential to conflict with energy standards and regulations.
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3.5.5 Cumulative Impact Analysis
Potential cumulative impacts on energy would result if the project, in combination with past, present, and future projects, would result in the wasteful or inefficient use of energy. This could result from development that would not incorporate sufficient building energy efficiency features, would not achieve building energy efficiency standards, or would result in the unnecessary use of energy during construction and/or operation. The cumulative projects within the areas serviced by the energy service providers would be applicable to this analysis ; this includes existing aging structures that are energy inefficient. Projects that include development of large buildings or other structures that would have the potential to consume energy in an inefficient manner would have the potential to contribute to a cumulative impact. Projects that would mostly include constructi on, such as transportation infrastructure, could also contribute to a cumulative impact; however, the impact of these projects would be limited because they would typically not involve substantial ongoing energy use.
As described previously in Section 3.5.4, Project Impact Analysis , the project would not result in significant environmental impacts due to wasteful, inefficient, or unnecessary use of energy. Like the project, cumulative projects would be subject to CALGreen, which provides energy efficiency standards for commercial and residential buildings. Over time, CALGreen would implement increasingly stringent energy efficiency standards that would require the project, and the cumulative projects, to minimize the wasteful and inefficient use of energy. In addition, cumulative projects would be required —at a minimum—to meet Title 24 building standards, further avoiding the inefficient use of energy.
Furthermore, various federal and state regulations, including the Low Carbon Fuel Standard, Pavley Clean Car Standards, and Low Emission Vehicle Program, would serve to reduce the transportation fuel demand of cumulative projects.
In summary, the project contains energy-efficiency design features consistent with the City’s CAP , would comply with applicable regulatory standards for the enhancement of energy efficiency, and would not conflict with or obstruct a state or local plan for renewable energy or energy efficiency. Thus, the project would not contribute to a cumulative impact to the wasteful or inefficient use of energy , and would not result in a cumulatively considerable contribution to a potential cumulative impact.
3.5.6 Mitigation Measures
Impacts would be less than significant, and no mitigation measures are required.
3.5.7 Conclusion
The project would comply with regulatory requirements and would implement applicable project design features in the City’s CAP Consistency Checklist that would reduce operational energy consumption.
For example, t he project would be required to install EV charging stations, PV panels , reduce
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landscaping water use, and plant trees . As such, the project would not result in the wasteful or inefficient use of energy, and impacts would be less than significant.
Additionally, the project would not conflict with any applicable plan, policy, or regulation adopted for the purpose of reducing energy consumption, including the City’s General Plan policies and City’s CAP Consistency Checklist. As a result, impacts would be less than significant.
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3.6 GEOLOGY AND SOILS
This section describes the existing geological and paleontological settings of the proposed Hughes Circuits Project (project), identifies associated regulatory requirements, evaluates potential impacts, including seismic activity, liquefaction, landslides, loss of topsoil, soil erosion, soil stability and soil expansion, and identifies mitigation measures related to implementation of the project.
Preparation of this environmental impact report ( EIR) section relied on information provided in the Preliminary Geotechnical Investigation prepared for the project by Geocon Inc. dated October 1, 2021.
The Preliminary Geotechnical Investigation is included as Appendix E to this EIR.
The paleontological findings are based on the results of the g eotechnical study, geological map and paleontological literature review, as well as a records search performed by the San Diego Natural History Museum.
A summary of the project- and cumulative-level geology and soils analysis, by threshold, is provided in Table 3.6-1, Geology and Soils Summary of Impacts.
Table 3.6-1
Geology and Soils Summary of Impacts
Threshold of Significance Project-Level Impact
Cumulative-
Level Impact
Significance
Determination
#1 - Directly or indirectly cause potential
substantial adverse effects, including the risk of
loss, injury, or death involving rupture of a known
earthquake fault, as delineated on the most
recent Alquist-Priolo Earthquake Fault Zoning Map
issued by the State Geologist for the area or
based on other substantial evidence of a known
fault. Refer to Division of Mines and Geology
Special Publication 42.
Less than Significant Less than
Significant
Less than
Significant
#2 – Directly or indirectly cause potential
substantial adverse effects, including the risk of
loss, injury, or death involving strong seismic
ground shaking.
Less than Significant Less than
Significant
Less than
Significant
#3 – Directly or indirectly cause potential
substantial adverse effects, including the risk of
loss, injury, or death involving strong seismic-
related ground failure, including liquefaction.
Less than Significant Less than
Significant
Less than
Significant
#4 – Directly or indirectly cause potential
substantial adverse effects, including the risk of
loss, injury, or death involving landslides.
No Impact No Impact No Impact
#5 – Result in substantial soil erosion or the loss
of topsoil.
Less than Significant Less than
Significant
Less than
Significant
#6 – Be located on a geologic unit or soil that is
unstable, or that would become unstable as a
Less than Significant Less than
Significant
Less than
Significant
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Table 3.6-1
Geology and Soils Summary of Impacts
Threshold of Significance Project-Level Impact
Cumulative-
Level Impact
Significance
Determination
result of the project, and potentially result in on- or off-site landslide, lateral spreading, subsidence,
liquefaction or collapse.
#7 – Be located on expansive soil, as defined in
Table 18-1-B of the Uniform Building Code (1994),
creating substantial direct or indirect risks to life
or property.
Less than Significant Less than
Significant
Less than
Significant
#8 Have soils incapable of adequately supporting
the use of septic tanks or alternative waste water
disposal systems where sewers are not available
for the disposal of waste water?
No Impact No Impact No Impact
#9 Directly or indirectly destroy a unique
paleontological resource or site unique geologic
feature?
Potentially
Significant
Potentially
Significant
Less than
Significant
3.6.1 Existing Conditions
The project site is located in the northeastern portion of the coastal plain within the southern portion of the Peninsular Ranges Geomorphic Province of southern California. The Peninsular Ranges is a geologic and geomorphic province that extends from the Imperial Valley to the Pacific Ocean and from the Transverse Ranges to the north and into Baja California to the south. The coastal plain of San Diego County is underlain by a thick sequence of relatively undisturbed and non-conformable sedimentary rocks that thicken to the west and range in age from Late Cretaceous through the Pleistocene with intermittent deposition. The sedimentary units are deposited on Jurassic and Cretaceous igneous and metavolcanic bedrock. Geomorphically, the coastal plain is characterized by a series of 21, stair-stepped marine terraces (younger to the west) that have been dissected by west flowing rivers.
The coastal plain is a relatively stable block that is dissected by relatively few faults con sisting of the potentially active La Nacion Fault Zone and the active Rose Canyon Fault Zone. The Peninsular Ranges Province is also dissected by the Elsinore Fault Zone that is associated with and sub -parallel to the San Andreas Fault Zone, which is the plate boundary between the Pacific and North American Plates.
The site is composed of Tertiary-age sedimentary rocks consisting of the Santiago Formation. No faults are shown in the immediate project site vicinity (Appendix E).
Soils
A brief description of the earth materials encountered during subsurface exploration is presented in the following sections. Based on field observations and review of published geologic maps, the project site is locally underlain by undocumented fill, young alluvium, and Santiago Formation bedrock.
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Undocumented Fill (Qudf)
Undocumented fill soils were observed to a depth of approximately 2 feet on site and mostly located in the southwestern portion of the site, along adjacent existing roadways and over the existing sewer line that traverses the site (Appendix E). These soils are not considered suitable for support of structural site improvements but may be re-used as engineered fill if properly processed and placed.
Alluvium (Qal and Qya)
Alluvium was encountered in all of the exploratory trenches to depths ranging between 3.5 and 10 feet.
The upper portion of the alluvium is considered unsuitable for the support of foundations or structural fill and would require remedial grading. The alluvium is considered acceptable for reuse as fill; however, some soil is saturated and would requir e mixing with drier material or require drying of the soil to obtain a proper moisture content during fill placement and compaction (Appendix E).
The young alluvial flood plain deposits (mapped as Qya) are Holocene (less than 11,700 years ago) (Cohen et al. 2022) and late Pleistocene (approximately 11,700 years ago to 129,000 years ago ) (Cohen et al. 2022) in age according to published mapping by Kennedy et al . (2007). Younger, Holocene age alluvial flood plain deposits at the surface have a low paleontological sensitivity, while high paleontological sensitivity deposits of Pleistocene age may be encountered at depth.
Santiago Formation (Tsa)
The Santiago Formation is present below the undocumented fill and alluvium across the site. The Santiago Formation was encountered between 3.5 and 10 feet below existing grade and is considered suitable for the support of proposed fill and structural loads. The presence of siltstone and claystone layers within this geologic unit would require slope stabilization methods within proposed cut slopes including buttresses and slope stabilization fills (Appendix E).
The Santiago Formation, formerly the Tejon Formation (English and Prutzman 1926), was first described and named by Woodring and Popenoe (1945) based on the type section located in the Santa Ana Mountains of Orange County. The formation consists of sparsely fossiliferous marine siltstones and sandstones; however, the upper Santiago Formation is likely non -marine due to the presence of petrified wood (Schoellhamer et al. 1981). As discussed in Mihlbachler and Deméré (2009, 2010), the Santiago Formation was divided into three distinct units: basal, middle, and upper.
The basal unit (Informal Member A) consists of coarse-grained arkosic sandstone that is generally not bedded; the middle unit (Informal Member B) consists of interbedded fine- to medium-grained arkosic sandstones, siltstones, and mudstones ; and the upper unit (Member C) consists of coarse -grained arkosic sandstone and grit (Kennedy and Tan 2007; Mihlbachler and Deméré 2009, 2010).
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The Santiago Formation, especially members B and C, has a high paleontological sensitivity (County of San Diego 2009; SDNHM 2023; Tomiya 2013; Zack et al. 2022; Tomiya 2011; López-Torres et al. 2018; Colbert 2006; Mihlbachler and Deméré 2009; Theodor 1999; Haug et al. 2013). The geotechnical report findings (Appendix E) of the sedimentary layers within the Santiago Formation as siltstone, claystone, and sandstone within the test trenches indicate a potential for these members being present within the project area, at depth, and are therefore assigned high paleontological sensitivity.
Surface Water and Groundwater
Surface Water
Surface water was not observed during the project site visit. If encountered during earthwork construction, surface water on this site is likely the result of precipitation.
Groundwater
Groundwater was encountered during the field investigation in the trench location at the project site at a depth between 4 and 10 feet below existing grade . The use of dewatering techniques may be necessary if excavations below the groundwater elevation occur. It is not uncommon for groundwater or seepage conditions to develop where none previously existed. Groundwater and seepage is dependent on seasonal precipitation, irrigation, land use, among other factors, and varies as a result (Appendix E).
Earthquake Hazards
Surface Fault Rupture
The geologic structure of the entire southern California area is dominated mainly by northwest trending faults associated with the San Andreas Fault system. The project site is in a seismically active region.
The potential for ground rupture is considered to be very low due to the absence of active faults at the project site (Appendix E). No faults transecting the project site were identified on the readily available geologic maps. The nearest known active fault is the Newport Inglewood –Rose Canyon Fault located about 10 miles southwest of the project site.
Liquefaction/Seismic Settlement
Liquefaction describes a phenomenon in which cyclic stresses, produced by earthquake -induced ground motion, create excess pore pressures in relatively cohesionless soils. These soils may thereby acquire a high degree of mobility, which can lead to lateral movement, sliding, consolidation and settlement of loose sediments, sand boils and other damaging deformations. This phenomenon occurs only below the water table, but, after liquefaction has developed, the effects can propagate upward into overlying non-saturated soil as excess pore water dissipates.
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The factors known to influence liquefaction potential include soil type and grain size, relative density, groundwater level, confining pressures, and both intensity and duration of ground shaking. In general, materials that are susceptible to liquefaction are loose, saturated granular soils having low fines content under low confining pressures.
Although groundwater is present near existing grade, liquefaction potential for the site is considered very low due to the very dense nature of the underlying Santiago Formation and the removal of the alluvium and undocumented fill (Appendix E).
Other Seismic Hazards
Due to the relatively flat nature of the project site, the potential for landslides and rockfall is considered negligible. The project site is located in a zone with “zero susceptibility” to landslides (City of San Marcos 2012).
In addition, the potential for secondary seismic hazards such as seiche and tsunami is remote due to site elevation and distance from an open body of water.
Paleontological Resources
The preliminary geotechnical investigation prepared for the project did not identify any unique geologic features on the project site. The geotechnical investigation (Appendix E) along with geologic mapping of the area (Kennedy et al. 2007) did show the highly paleontological sensitive Santiago Formation was present, and furthermore the geotechnical evaluation reported the presence of sandstone, siltstone, and claystone layers within the project site encountered between 3 to 10 feet. These suggest the presence of members B and/or C of the Santiago Formation, which have a high paleontological sensitivity.
Dudek requested a paleontological records search from the San Diego Museum of Natural History on January 2 6, 2023 , and received the results on February 6, 2023. The museum reported that no previous localities were reported from within the project site and six localities from within the 1 -mile buffer. These localities (6878, 6879, 6880, 6881, 6882, 6883) were all from Member B of the Santiago Formation in San Marcos, C alifornia. They consisted of 140 individual specimens of snails (Gastropoda), pelecypods (Mollusca), plant material, bryozoans, burrows ( Ichnofossils), and a fish tooth (Osteichthyes) (SDNHM 2023). Terrestrial vertebrate fossils and invertebrate fossil assemblages have also been recovered elsewhere in San Diego County (Deméré and Walsh 1993; SDNHM 2023).
3.6.2 Regulatory Setting
This section describes the federal, state and local regulations related to geology and soils.
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Federal
Federal Disaster Mitigation Act of 2000
The Disaster Mitigation Act of 2000 provides a set of mitigation plan requirements that encourage state and local jurisdictions to coordinate disaster mitigation planning and implementation. The Act also encourages states to complete a Natural Mitigation Plan. California’s relevant and updated State Hazard Mitigation Plan was adopted and approved by the Federal Emergency Management Agency Region IX in 2007. In accordance with this Act, the County of San Diego (County) prepared its Multi- Jurisdictional Hazard Mitigation Plan, which is discussed in more detail below.
Federal Response Plan
The Federal Response Plan of 1999 is a signed agreement among 27 federal departments and agencies, including the American Red Cross, that (1) provides the mechanism for coordinating delivery of federal assistance and resources to augment efforts of state and local governments overwhelmed by a major disaster or emergency; (2) supports implementation of the Robert T. Stafford Disaster Relief and Emergency Act, as well as individual agency statutory authorities; and (3) supplements other federal emergency oper ations plans developed to address specific hazards. The Federal Response Plan is implemented in anticipation of a significant event likely to result in a need for federal assistance or in response to an actual event requiring federal assistance under a pre sidential declaration of a major disaster or emergency.
U.S. Geological Survey Landslide Hazard Identification Program The U.S. Geological Survey, in fulfillment of the requirements of Public Law 106-113, created the National Landslide Hazards Program to reduce long-term losses from landslide hazards by improving understanding of the causes of ground failure and suggesting mitigation strategies. The Federal Emergency Management Agency is the responsible agency for the long-term management of natural hazards.
International Building Code
The International Building Code (IBC) is a model building code developed by the International Code Council that provides the basis for the C alifornia Building Code (CBC). The purpose of the IBC is to provide minimum standards for building construction to ensure public safety, health, and welfare. Prior to the creation of the IBC, several different building codes were used; however, by 2000, the IBC had replaced these previous codes. The IBC is updated every 3 years.
Paleontological Resources Protection Act
The Paleontological Resources Protection Act (PRPA) of 2009 directs the Secretaries of the Interior and Agriculture to manage and protect paleontological resources on federal land using “scientific principles and expertise.” The PRPA incorporates most of the recommendations of the Secretary of the
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Interior’s report titled Assessment of Fossil Management on Federal and Indian Lands (DOI 2000) to formulate a consistent paleontological resources management framework. In passing the PRPA, congress officially recognized the scientific importance of paleo ntological resources on some federal lands by declaring that fossils from these lands are federal property that must be preserved and protected. The PRPA codifies existing policies of the U.S. Bureau of Land Management, National Park Service, U.S. Forest S ervice, Bureau of Reclamation, and the U.S. Fish and Wildlife Service, and provides the following:
• Criminal and civil penalties for illegal sale and transport and theft and vandalism of fossils from federal lands
• Minimum requirements for paleontological resource -use permit issuance (terms, conditions, and qualifications of applicants)
• Definitions for “paleontological resources” and “casual collecting” • Requirements for curation of federal fossils in approved repositories The PRPA requires the Secretaries of the Interior and Agriculture to manage and protect paleontological resources on federal land. The PRPA furthers the protection of fossils on federal lands by criminalizing the unauthorized removal of fossils.
Federal Land Policy Management Act
The Federal Land Policy Management Act of 1976 (PL 94 -579; 90 Statute 2743, USC 1701 –1782) requires that public lands be managed such that the quality of their scientific values is protected. The act recognizes significant paleontological resources as scie ntific resources and requires federal agencies to manage public lands in a manner that protects scientific resource quality.
National Environmental Policy Act
The National Environmental Policy Act of 1969 (PL 91 -190; 31 Statute 852, 42 USC 4321–4327) requires that important natural aspects of national heritage be considered in determining the environmental consequences of proposed projects.
State
Alquist-Priolo Earthquake Fault Zoning Act
The Alquist-Priolo Earthquake Fault Zoning Act mitigates the hazard of surface fault rupture by regulating structures designated for human occupancy near active faults. As required by the Act, the California Geological Survey has delineated Earthquake Fault Zones along known active faults in California.
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California Geologic Survey
The California Geologic Survey provides guidance with regard to seismic hazards. The California Geologic Survey’s Special Publication 117A, Guidelines for Evaluating and Mitigating Seismic Hazards in California (2008), provides guidance for the evaluation and mitigation of earthquake -related hazards for projects located within certain designated zones.
California Surface Mining and Reclamation Act
Enacted to promote conservation and protection of significant mineral deposits, the California Surface Mining and Reclamation Act requires cities address the significant aggregate resources classified by the State Geologist and designated by the State Mining and Geology Board in their General Plans. The Act ensures that significant aggregate resources are recognized and considered before land use decisions are made that may compromise the availability of these resources.
Seismic Hazards Mapping Act
The Seismic Hazards Mapping Act (SHMA) was enacted in 1997 to protect the public from strong ground shaking, liquefaction, landslides, or other ground failure, and from other hazards caused by earthquakes.
The SHMA requires the State Geologist to map areas subject to seismic hazard. Before a development permit may be granted for projects located in designated areas, a geotechnical evaluation of the site must be prepared, and appropriate mitigation measures incorporated into the project design.
Additionally, the SHMA requires a Standardized Natural Hazards Disclosure Statement form be completed by real estate sellers if a property is within one of the designated natural hazards areas.
Natural Hazards Disclosure Act
The Natural Hazards Disclosure Act (effective June 1, 1998), requires “sellers of real property and their agents provide prospective buyers with a ‘Natural Hazard Disclosure Statement’ when the property being sold lies within one or more state-mapped hazard areas, including a Seismic Hazard Zone.” The SHMA, discussed above, specifies two ways this disclosure can be made:
• The Local Option Real Estate Transfer Disclosure Statement as provided in Section 1102.6a of the Civil Code; or
• The Natural Hazard Disclosure Statement as provided in Section 1103.2 of the Civil Code.
The Local Option Real Estate Disclosure Statement can be substituted for the Natural Hazards Disclosure Statement if it contains substantially the same information and substantially the same warning as the Natural Hazards Disclosure Statement. Both the Alq uist-Priolo Act and the SHMA require that real estate agents, or sellers of real estate acting without an agent, disclose to prospective
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buyers that the property is located in an Alquist -Priolo Earthquake Fault Zone or Seismic Hazard Mapping Zone.
California Uniform Building Code
The California Building Standards Code is codified in Title 24 of the California Code of Regulations.
Part 2 of the California Uniform Building Code specifies standards for geologic and seismic hazards, other than surface faulting. Chapter 23 of the California U niform Building Code addresses seismic safety and includes regulations for earthquake-resistant design and construction. The 2019 Triennial Edition of the California Building Standards Code went into effect January 1, 2020 (California Building Standards Commission 2020).
California Environmental Quality Act of 1970
Paleontological resources are afforded consideration under the California Environmental Quality Act (CEQA). Appendix G of the State of California CEQA Guidelines (14 CCR 15000 et seq.) includes the following as one of the questions to be answered in the Environmental Checklist (Appendix G, Section VII, Part f): “Would the project directly or indirectly destroy a unique paleontological resource or site or unique geologic feature?” California Public Resources Code Section 5097.5 specifies that any unauthorized removal of paleontological remains is a misdemeanor. Further, California Penal Code Section 622.5 sets the penalties for damage to or removal of paleontological resources. California state laws and regulations under California Public Resources Code Secti on 5097.5 apply to paleontological resources.
PRC 5097–5097.6 – Archaeological, Paleontological and Historical Sites PRC Section s 5097–5097.6 outlines the requirements for cultural resource analysis prior to the commencement of any construction project on State Lands. This section identifies that the unauthorized disturbance or removal of archaeological, historical, or paleontological resources located on public lands is a misdemeanor. It prohibits the knowing destruction of objects of antiquity without a permit (expressed permission) on public lands, and provides for criminal sanctions. This section was amended in 1987 t o require consultation with the California Native American Heritage Commission whenever Native American graves are found. Violations for the taking or possessing remains or artifacts are felonies.
Local
County of San Diego Multi-Jurisdictional Hazard Mitigation Plan To comply with the Disaster Mitigation Act of 2000, the County of San Diego prepared the Multi-Jurisdictional Hazard Mitigation Plan in 200 4, revised in 2017 . The Plan serves as both a
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county-wide plan and a plan for local jurisdictions that identifies risks posed by natural and human-made disasters before a hazard event occurs. The Plan includes overall goals and objectives shared by many jurisdictions, as well as specific goals, objectives, and mitigation action items for each of the participating jurisdictions, including the City of San Marcos, developed to help minimize the effects of the specified hazards that potentially affect their jurisdiction (County of San Diego 2017).
County of San Diego Code of Regulatory Ordinances Sections 87.101–87.804, Grading, Clearing, and Watercourses Ordinance
Section 87.430 of the County’s Grading and Clearing Ordinance provides for the requirement of a paleontological monitor at the discretion of the County. In addition, the suspension of grading operation is required upon the discovery of fossils greater than 12 inches in any dimension. The ordinance also requires notification of the County Official (e.g., Permit Compliance Coordinator). The ordinance gives the County Official the authority to determine the appropriate resource recovery operations, which shall be carried out prior to the County Official’s authorization to resume normal grading operations.
San Marcos Grading Ordinance
The City’s Grading Ordinance (found in Chapter 17.32 of the City’s Municipal Co de) contains regulations for the purpose of protecting public health and safety with respect to the design and construction of building sites and the development of property by grading. The ordinance sets forth rules and regulations to control excavation, grading and earthwork construction, engineering analysis of soil conditions, and the administrative procedure for issuance of grading permits, approval of grading plans, and site inspections.
City of San Marcos General Plan
Safety Element
The Safety Element of the San Marcos General Plan contains several policies pertaining to natural geologic hazards. The following goal and policies apply to the project (City of San Marcos 2012):
• Goal S-1: Reduce risks to the community from earthquakes by regulating new development and redevelopment to prevent the creation of new geologic and seismic hazards. o Policy S-1.1: Reduce the risk of impacts from geologic and seismic hazards by applying current and proper land use planning, development engineering, building construction, and retrofitting requirements.
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o Policy S-1.2: Investigate specific groundwater levels and geologic conditions underlying all new development or redevelopment proposals in areas where potential fault rupture, liquefaction, or other geologic hazards are suspected.
The project’s consistency with applicable General Plan goals and policies is discussed in Section 3.10, Land Use. As detailed in Section 3.10, the project is consistent with the applicable General Plan goals and policies pertaining to geology and soils.
Conservation and Open Space Element
• Goal COS -2: The City is committed to conserving, protecting, and maintaining open space, agricultural, and limited resources for future generations. By working with property owners, local organizations, and state and federal agencies, the City can limit the conversi on of resource lands to urban uses.
o Policy COS -2.5: Continue to review future development proposals to ensure that cultural resources (including prehistoric, historic, paleontological, and Senate Bill 18 Tribal resources) are analyzed and conserved in compliance with CEQA requirements. • Goal COS-11: Continue to identify and evaluate cultural, historic, archeological, paleontological, and architectural resources for protection from demolition and inappropriate actions.
3.6.3 Thresholds of Significance
As defined in Appendix G of the CEQA Guidelines , project impacts to geological resources are considered significant if the project would:
• Threshold #1: Directly or indirectly cause potential substantial adverse effects, including the risk of loss, injury, or death involving rupture of a known earthquake fault, as delineated on the most recent Alquist-Priolo Earthquake Fault Zoning Map issued by the State Geologist for the area or based on other substantial evidence of as known fault. Refer to Division of Mines and Geology Special Publication 42.
• Threshold #2: Directly or indirectly cause potential substantial adverse effects, including the risk of loss, injury, or death involving strong seismic ground shaking. • Threshold #3: Directly or indirectly cause potential substantial adverse effects, including the risk of loss, injury, or death involving seismic-related ground failure, including liquefaction. • Threshold #4: Directly or indirectly cause potential substantial adverse effects, including the risk of loss, injury, or death involving landslides.
• Threshold #5: Result in substantial soil erosion or the loss of topsoil.
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• Threshold #6: Be located on a geologic unit or soil that is unstable, or that would become unstable as a result of the project, and potentially result in on - or off-site landslide, lateral spreading, subsidence, liquefaction or collapse.
• Threshold #7: Be located on expansive soil, as defined in Table 18-1-B of the Uniform Building Code (1994), creating substantial direct or indirect risks to life or property. • Threshold #8: Have soils incapable of adequately supporting the use of septic tanks or alternative waste water disposal systems where sewers are not available for the disposal of waste water.
• Threshold #9: Directly or indirectly destroy a unique paleontological resource or site or unique geologic feature.
3.6.4 Project Impact Analysis
Impacts to geology and soils that may result from ground disturbing activities associated with the project are analyzed below.
Threshold #1: Would the project directly or indirectly cause potential substantial adverse effects, including the risk of loss, injury, or death involving rupture of a known earthquake fault, as delineated on the most recent Alquist-Priolo Earthquake Fault Zoning Map issued by the State Geologist for the area or based on other substantial evidence of as known fault. (Refer to Division of Mines and Geology Special Publication 42)?
As identified in Section 3.6.1, Existing Conditions, the project site is located in tectonically active southern California. However, no Alquist -Priolo Fault Hazard Zones or other known active faults run through the project site. The closest known active fault is the Newport-Inglewood/Rose Canyon Fault, located approximately 10 miles southwest of the project site. Based on the lack of active or potentially active faults underlying the project area, the potential for surface rupture is low and the project site would not be subject to a greater seismic risk than other locations within the region. Additionally, per the Alquist- Priolo Earthquake Fault Zoning Act, because the project site is not located in an Alquist Priolo Fault Zone, the project would not place any prohibited uses (e.g., uses containing structures with a capacity of 300 people or more; uses with the potential to severely damage the environment or cause major loss of life; or specific civic uses including police and fire stations, schools, hospitals, rest homes, nursing homes, and emergency communication facilities) within an Alquist–Priolo Fault Zone. Thus, the potential for loss, injury, or death involving rupture of a known earthquake fault is considered low.
The project would be required to comply with applicable CBC requirements and proposed plans would be subject to City review. For these reasons, impacts are determined to be less than significant.
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Threshold #2: Would the project directly or indirectly cause potential substantial adverse effects, including the risk of loss, injury, or death involving strong seismic ground shaking? There are no known active faults that run through the project site. The project would be designed in accordance with applicable CBC criteria, including those specific to resistance to seismic shaking.
Furthermore, the project would be constructed in accordance with other applicable regulations, current seismic design specifications of the Structural Engineers Association of California, and applicable requirements of the State of California Occupational Safety and Health Administration.
These required seismic design considerations are used to minimize structural damage in the event of ground shaking.
Additionally, the project would implement all recommendations outlined in Section 7 of the Preliminary Geotechnical Investigation (Appendix E), as well as any project -specific recommendations with any potential supplemental geotechnical evaluations in compliance with Section 17.32.040(d) of the City’s Municipal Code . Section 17.32.040( d) of the Municipal Code requires the incorporation of recommendations of geotechnical reports into grading plans prior to the approval of a grading permit.
These recommendations include general provisions for compliance with the City’s grading ordinances as well as recommendations related to property clearing and preparation, remedial grading, engineered fill, excavation, shrinkage and bulking, trench excavation and backfill. The Preliminary Geotechnical Investigation includes design and construction recommendations, and post-construction considerations. The detailed recommendations are included in Chapter 7 of the Preliminary Geotechnical Investigation (see Appendix E). The Development Services Department shall review and approve project design and inspect construction to verify that the geotechnical recommendations have been incorporated. With adherence to all regulations and geotechnical recommendations from the Preliminary Geotechnical Investigation conducted for the project , impacts related to seismic gr ound shaking would be considered less than significant.
Threshold #3: Would the project directly or indirectly cause potential substantial adverse effects, including the risk of loss, injury, or death involving seismic-related ground failure, including liquefaction? Liquefaction typically occurs when a site is subjected to strong seismic shaking, on -site soils are cohesionless, groundwater is encountered within 50 feet of the surface, and soil relative densities are less than approximately 70%. Based on the preliminary geotechnical evaluation mapping, subsurface exploration, and laboratory testing, the project site is not identified as being susceptible to liquefaction (Appendix E). Although groundwater is present near existing grade, liquefaction potential for the site is considered very low due to the very dense nature of the underlying Santiago Formation and the removal of the alluvium and undocumented fill. The potential for liquefaction or dynamic settlement to occur on site is considered very low. Additionally, the project site is identified in the City ’s Safety Element as having “Zero Susceptibility” to liquefaction (Figure 6-1 of the City’s General Plan) (City of
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San Marcos 2012). As such, the project site is not considered susceptible to liquefaction or significant amounts of seismic settlement.
Furthermore, the project would implement all remedial grading and drainage recommendati ons contained within the Preliminary Geotechnical Investigation (see Appendix E of this EIR), in addition to recommendations outlined in any development project -specific supplemental geotechnical report(s) in accordance with Municipal Code requirements. For these reasons, implementation of the project would not result in seismic -related ground failure, including liquefaction and impacts would be less than significant.
Threshold #4: Would the project directly or indirectly cause potential substantial adverse effects, including the risk of loss, injury, or death involving landslides? The project site is relatively flat, with elevations varying from approximately 524 to 532 feet above mean sea level. The project site is identified in the City's Safety Element as having “Zero Susceptibility” to landslides (Figure 6-1 of the General Plan) (City of San Marcos 2012). Therefore, the project site is not considered susceptible to landslides and project no impacts would occur.
Threshold #5: Would the project result in substantial soil erosion or the loss of topsoil? The project would be required to comply with the City’s Grading Ordinance, which contains design standards and performance requirements that must be met to avoid or reduce, to an acceptable level, excessive erosion. Furthermore, in accordance with Municipal Code requirements, the project would implement all recommendations pertaining to soil erosion or loss of topsoil as contained within the Preliminary Geotechnical Investigation (Appendix E), in additional to any additional recommendations from any supplemental geotechnical reports prepared for the project. For these reasons, implementation of the project would not result in substantial soil erosion o r the loss of topsoil , and impacts would be less than significant.
Threshold #6: Would the project be located on a geologic unit or soil that is unstable, or that would become unstable as a result of the project, and potentially result in on - or off-site landslide, lateral spreading, subsidence, liquefaction or collapse?
As previously described under Threshold #3 and #4, the potential for landslides and/or liquefaction on site is considered low. The project would be required to comply with the recommendations of the preliminary geotechnical investigation (Appendix E), which require that where not already removed by the proposed site grading, any topsoil or any undocumented fill encountered should be completely removed and recompacted w ithin the limits of grading, receive additional fill as needed , and implement any other settlement-sensitive improvements as needed. Site preparation, removals, and excavation associated with the project would be perfo rmed consistent with Chapter 7 of the Preliminary Geotechnical Investigation (Appendix E) and any supplemental geotechnical evaluation. In
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addition, grading associated with the project would be accomplished under the observation and testing of the project geotechnical engineer and engineering geologist, in accordance with the requirements of the CBC, the City of San Marcos, and the County of San Diego. Areas to receive fill would be required to be properly cut and/or benched in accordance with current industry standards of practice , CBC guidelines, and the City of San Marcos requirements.
Therefore, compliance with applicable regulations and the recommendations in the Preliminary Geotechnical Investigation would ensure that the potential for unstable conditions that could result in on- or off-site lateral spread, subsidence, liquefaction or collapse would be less than significant.
Threshold #7: Would the project be located on expansive soil, as defined in Table 18 -1-B of the Uniform Building Code (1994), creating substantial direct or indirect risks to life or property? As described in the Preliminary Geotechnical Investigation (Appendix E), the project site contains soils with a low to medium expansion index , specifically the undocumented fill soils. These soils are proposed to be removed, and the imported fill will be tested prior to its arrival at the site to determine its suitability as fill material. The project would be required to implement CBC guidelines, regulations, and further recommendations to ensure that such soils are fully remediated and/or the project is designed appropriately to minimize impacts of expansive soils. The preliminary geotechnical evaluation also includes recommendations that expan sive or clayey soils are not used for backfill materials. With adherence to the Preliminary Geotechnical Investigation recommendations as required for grading permit issuance, impacts related to expansive soils would be less than significant.
Threshold #8: Would the project have soils incapable of adequately supporting the use of septic tanks or alternative wastewater disposal systems where sewers are not available for the disposal of wastewater? The project does not include septic tanks or alternative wastewater disposal systems. As described in Section 3.17, Utilities and Service Systems, the project would construct private on-site sewer lines that would connect to existing sewer district infrastructure. Therefore, no impacts would occur.
Threshold #9: Would the project directly or indirectly destroy a unique paleontological resource or site or unique geologic feature?
As discussed in Section 3.6.1, the potential for paleontological resources to be located within the project site is considered high. Ground-disturbing activities associated with the project have the potential to unearth previously unidentified paleontological resources . The preliminary geotechnical evaluation prepared for the project did not identify any unique geologic features on the project site .
However, paleontological resources may be adversely impacted during excavation (Impact GEO-1), and therefore impacts are determined to be potentially significant without mitigation.
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3.6.5 Cumulative Impact Analysis
Due to the localized nature of geology and soils, cumulative projects would address potential impacts to geology and soils on a project -by-project basis, as potential geologic hazards and soil composition vary by site. Each cumulative project would be required to assess individual and site-specific geologic conditions, which would inform construction and development of each site. All cumulative development would be subject to similar requirements to those imposed and implemented for the project and would be required to adhere to applicable regulations, standards, and procedures.
Further, as discussed in Section 3.6.4, Project Impact Analysis, the project site has high potential to yield paleontological resources. Thus, impacts to paleontological resources from implementation of the project would be significant with no mitigation. While some of the projects on the cumulative list are located in areas that may contain paleontological resources, the presence of these resources is typically unknown prior to construction, and it is expected that mitigation measures would be included with approval of cumulative projects to ensure that impacts to paleontological resources are minimized.
All cumulative projects would be required to analyze site -specific conditions and implement recommendations or mitigation . Nevertheless , because the project would result in potentially significant impacts to paleontological resources prior to mitigation, cumulative impacts related to geology and soils is determined to be potentially significant.
3.6.6 Mitigation Measures
Based on the a nalysis presented in Section s 3.6.4 and 3.6 .5, most project- and cumulative -level geology- and soil-related impacts would be less than significant; however, impacts to paleontological resources would be potentially significant. Therefore, monitoring would be required for all disturbance within the middle-Eocene Santiago Formation (Tsa) and in areas of young alluvial flood plain deposits (Qya) where underlying Pleistocene age deposits or Santiago Formation may be encountered at depth.
Without mitigation, the potential damage to paleontological resources during construction would be a potentially significant impact. With implementation of Mitigation Measure (MM-)GEO-1, outlined below, potential impacts related to paleontological resources would be reduced to less than significant.
MM-GEO-1 Prior to commencement of any grading activity on site, the applicant shall retain a qualified paleontologist meeting the Society of Vertebrate Paleontology (SVP) (2010) guidelines. The paleontologist shall prepare a Paleontological Resources Impact Mitigation Program (PRIMP) for the Project. The P RIMP shall be consistent with the guidelines of the SVP (2010) and include the following elements: project description, preconstruction worker environmental awareness training, frequency of monitoring, salvage protocols, reporting, and collections management. The qualified paleontologist or a qualified monitor meeting the SVP (2010) guidelines shall be on site during all rough grading and other significant ground-disturbing activities below a
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depth of 5 feet below the existing ground surface in previously undisturbed , Pleistocene-age deposits and all disturbance within the middle Eocene age Santiago Formation. If excavations below 5 feet are not impacting previously undisturbed deposits, as determined by the qualified paleontologist, spot -check monitoring shall ensue. In the event that paleontological resources (e.g., fossils) are unearthed during grading, the paleontological monitor shall temporarily halt and/or divert grading activity to allow recovery of the paleontological resources. The area of discovery shall be roped off with a 50 -foot-radius buffer to document and collect the fossils. Once documentation and collection of the find is completed, the monitor shall remove the rope and allow g rading to recommence in the area of the find. No monitoring is required during excavations that the paleontologist determines are within artificial fill or younger alluvium (e.g., Holocene age Quaternary alluvium, younger than approximately 11,700 years).
3.6.7 Conclusion
Based on the analysis presented in Section 3.6. 4, Project Impact Analysis, and Section 3.6.5, Cumulative Impact Analysis, impacts associated with seismicity, liquefaction, landslides, erosion/loss of topsoil, compressible soils, and expansive soils were determined to be less than significant. Impacts to paleontological resources would be potentially significant; however , with the implementation of MM-GEO-1 listed in Section 3.6.6, Mitigation Measures, the impacts would be reduced to that of less than signif icant. Implementation of applicable recommendations of the Preliminary Geotechnical Report (Appendix E) and any supplemental report, would further ensure no significant impacts related to geology and soils would occur as a result of project construction. Furthermore, the project would be required to comply with all applicable regulations outlined in Section 3.6.2, Regulatory Setting.
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3.7 Greenhouse Gas Emissions
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3.7 GREENHOUSE GAS EMISSIONS
This section describes the existing setting of the project site related to greenhouse gas ( GHG) emissions and climate change , identifies associated regulatory requirements, and evaluates potential impacts related to implementation of the Hughes Circuits Project (project). Information for this section relies on the Air Quality and G reenhouse Gas Emissions Technical Report prepared for the project by Dudek in January 2023. The Air Quality and Greenhouse Gas Emissions Technical Report is included as Appendix B to this environmental impact report.
A summary of the project- and cumulative-level GHG analysis, by threshold, is provided in Table 3.7-1.
Table 3.7-1
Greenhouse Gas Emissions Summary of Impacts
Threshold of Significance
Project
Direct
Impact
Project
Cumulative
Impact
Significance
Determination
#1 - Generate GHG emissions, either directly or
indirectly, that may have a significant impact on the
environment.
Less than
Significant
Less than
Significant
Less than
Significant
#2 - Conflict with an applicable plan, policy, or
regulation adopted for the purpose of reducing GHGs.
Less than
Significant
Less than
Significant
Less than
Significant
3.7.1 Existing Conditions
This section introduces the environmental setting as it relates to GHG emissions, providing a climate change overview; information on GHG and climate forcing substances, global warming potential, and sources of GHG emissions; and describing potential effects of climate change in the region of the project.
Climate Change Overview
Climate change refers to any significant change in measures of climate, such as temperature, precipitation, or wind patterns, lasting for an extended period of time ( i.e., decades or longer). The earth’s temperature depends on the balance between energy entering and leaving the planet’s system. Many factors, both natural and human, can cause changes in the earth’s energy balance, including variations in the sun ’s energy reaching the earth, changes in the reflectivity of the earth’s atmosphere and surface, a nd changes in the greenhouse effect, which affects the amount of heat retained by the earth’s atmosphere (EPA 2017).
The greenhouse effect is the trapping and build-up of heat in the atmosphere (troposphere) near the earth’s surface. The greenhouse effect traps heat in the troposphere through a threefold process as follows: Short-wave radiation emitted by the sun is absorbed by the earth, the earth emits a portion of
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this energy in the form of long -wave radiation, and GHGs in the upper atmosphere absorb this long - wave radiation and emit it into space and toward the earth. The greenhouse effect is a natural process that contributes to regulating the earth’s temperature and creates a pleasant, livable environment on the earth. Human activities that emit additional GHGs to the atmosphere increase the amount of infrared radiation that gets absorbed before escaping into space, thus enhancing the greenhouse effect and causing the earth’s surface temperature to rise.
The scientific record of the earth’s climate shows that the climate system varies naturally over a wide range of time scales and that, in general, climate changes prior to the Industrial Revolution in the 1700s can be explained by natural causes such as changes in solar energy, volcani c eruptions, and natural changes in GHG concentrations. Recent climate changes, in particular the warming observed over the past century, however, cannot be explained by natural causes alone. Rather, it is extremely likely that human activities have been the dominant cause of that warming since the mid -twentieth century and is the most significant driver of observed climate change (IPCC 2013; EPA 2017). Human influence on the climate system is evident from the increasing GHG concentrations in the atmosphere, positive radiative forcing, observed warming, and improved understanding of the climate system (IPCC 2013). The atmospheric concentrations of GHGs have increased to levels unprecedented in the last 800,000 years, primarily f rom fossil fuel emissions and secondarily from emissions associated with land use changes (IPCC 2013). Continued emissions of GHGs will cause further warming and changes in all components of the climate system, which is discussed further below under Potential Effects of Climate Change in Section 3.7.1, Existing Conditions.
Greenhouse Gases
A GHG is any gas that absorbs infrared radiation in the atmosphere; in other words, GHGs trap heat in the atmosphere. As defined in California Health and Safety Code, Section 38505(g), for purposes of administering many of the state’s primary GHG emissions reduction programs, GHGs include carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), sulfur hexafluoride (SF6), and nitrogen trifluoride (NF 3) (see also California Environmental Quality Act [CEQA] Guidelines, Section 15364.5). Some GHGs, such as CO2, CH4, and N2O, occur naturally and are emitted into the atmosphere through natural processes and human activities. Of these gases, CO2 and CH4 are emitted in the greatest quantities from human activities. Manufactured GHGs, which have a much greater heat-absorption potential than CO2, include fluorinated gases, such as HFCs, PFCs, and SF6, which are associated with certain industrial products and processes. The following paragraphs provide a summary of the most common GHGs and their sources.1
1 The descriptions of greenhouse gases are summarized from the Intergovernmental Panel on Climate Change (IPCC) Second Assessment Report (1995), IPCC Fourth Assessment Report (2007), the Glossary of Terms Used in GHG Inventories (CARB 2015), and the Glossary of Climate Change Terms (EPA 2016).
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Carbon Dioxide. CO2 is a naturally occurring gas and a by-product of human activities and is the principal anthropogenic GHG that affects the earth’s radiative balance. Natural sources of CO2 include respiration of bacteria, plants, animals, and fungus; evaporation from oceans; volcanic out -gassing; and decomposition of dead organic matter. Human activities that generate CO2 are from the combustion of fuels such as coal, oil, natural gas, and wood and changes in land use.
Methane. CH4 is produced through both natural and human activities. CH 4 is a flammable gas and is the main component of natural gas. Methane is produced through anaerobic (without oxygen) decomposition of waste in landfills, flooded rice fields, animal digestion, decomposition of animal wastes, production and distribution of natural gas and petroleum, coal production, and incomplete fossil fuel combustion.
Nitrous Oxide. N2O is produced through natural and human activities, mainly through agricultural activities and natural biological processes, although fuel burning and other processes also create N2O. Sources of N2O include soil cultivation practices (microbial processes in soil and water), especially the use of commercial and organic fertilizers, manure management, industrial processes (such as in nitric acid production, nylon production, and fossil-fuel-fired power plants), vehicle emissions, and using N2O as a propellant (e.g., rockets, racecars, and aerosol sprays).
Fluorinated Gases. Fluorinated gases (also referred to as F -gases) are synthetic powerful GHGs emitted from many industrial processes. Fluorinated gases are commonly used as substitutes for stratospheric ozone-depleting substances (e.g., chlorofluorocarbons [CFCs], hydrochlorofluorocarbons [HCFCs], and halons). The most prevalent fluorinated gases include the following:
• Hydrofluorocarbons: HFCs are compounds containing only hydrogen, fluorine, and carbon atoms. HFCs are synthetic chemicals used as alternatives to ozone -depleting substances in serving many industrial, commercial, and personal needs. HFCs are emitted as by-products of industrial processes and are used in manufacturing.
• Perfluorocarbons: PFCs are a group of human -made chemicals composed of carbon and fluorine only. These chemicals were introduced as alternatives, with HFCs, to the ozone depleting substances. The two main sources of PFCs are primary aluminum production and semiconductor manufacturing. Since PFCs have stable molecular structures and do not break down through the chemical processes i n the lower atmosphere, these chemicals have long lifetimes, ranging between 10,000 and 50,000 years.
• Sulfur Hexafluoride: SF6 is a colorless gas soluble in alcohol and ether and slightly soluble in water. SF 6 is used for insulation in electric power transmission and distribution equipment, semiconductor manufacturing, the magnesium industry, and as a tracer gas for leak detection. • Nitrogen Trifluoride: NF3 is used in the manufacture of a variety of electronics, including semiconductors and flat panel displays.
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Chlorofluorocarbons. CFCs are synthetic chemicals that have been used as cleaning solvents, refrigerants, and aerosol propellants. CFCs are chemically unreactive in the lower atmosphere (troposphere) and the production of CFCs was prohibited in 1987 due to the chemical destruc tion of stratospheric ozone (O3).
Hydrochlorofluorocarbons. HCFCs are a large group of compounds, whose structure is very close to that of CFCs—containing hydrogen, fluorine, chlorine, and carbon atoms —but including one or more hydrogen atoms. Like HFCs, HCFCs are used in refrigerants and propellants. HCFCs were also used in place of CFCs for some applications; however, their use in general is being phased out.
Black Carbon. Black carbon is a component of fine particulate matter, which has been identified as a leading environmental risk factor for premature death. It is produced from the incomplete combustion of fossil fuels and biomass burning, particularly from older diesel engines and forest fires. Black carbon warms the atmosphere by absorbing solar radiation, influences cloud formation, and darkens the surface of snow and ice, which accelerates heat absorption and melting. Black carbon is a short-lived species that varies spatially, which makes it difficult to quantify the global warming potential. Diesel particulate matter emissions are a major source of black carbon and are toxic air contaminants that have been regulated and controlled in California for several decades to protect public health. In relation to declining diesel particulate matter from the California Air Resources Board ( CARB) regulations pertaining to diesel engines, diesel fuels, and burning activities, CARB estimates that annual black carbon emissions in California have reduced by 70% between 1990 and 2010, with 95% control expected by 2020 (CARB 2014).
Water Vapor. The primary source of water vapor is evaporation from the ocean, with additional vapor generated by sublimation (change from solid to gas) from ice and snow, evaporation from other water bodies, and transpiration from plant leaves. Water vapor is the most important, abundant, and variable GHG in the atmosphere and maintains a climate necessary for life.
Ozone. Tropospheric O3, which is created by photochemical reactions involving gases from both natural sources and human activities, acts as a GHG. Stratospheric O 3, which is created by the interaction between solar ultraviolet radiation and molecular oxygen (O2), plays a decisive role in the stratospheric radiative balance. Depletion of stratospheric O3, due to chemical reactions that may be enhanced by climate change, results in an increased ground-level flux of ultraviolet-B radiation.
Aerosols. Aerosols are suspensions of particulate matter in a gas emitted into the air through burning biomass (plant material) and fossil fuels. Aerosols can warm the atmosphere by absorbing and emitting heat and can cool the atmosphere by reflecting light.
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Global Warming Potential
Gases in the atmosphere can contribute to climate change both directly and indirectly. Direct effects occur when the gas itself absorbs radiation. Indirect radiative forcing occurs when chemical transformations of the substance produce other GHGs, when a g as influences the atmospheric lifetimes of other gases, and/or when a gas affects atmospheric processes that alter the radiative balance of the earth (EPA 201 7). The Intergovernmental Panel on Climate Change developed the global warming potential (GWP) concept to compare the ability of each GHG to trap heat in the atmosphere relative to another gas. The GWP of a GHG is defined as the ratio of the time -integrated radiative forcing from the instantaneous release of 1 kilogram of a trace substance relative to that of 1 kilogram of a reference gas (IPCC 2014). The reference gas used is CO 2; therefore, GWP-weighted emissions are measured in metric tons (MT) of carbon dioxide equivalent (CO 2e).The current version of California Emissions Estimator Model ( CalEEMod) (Version 2020.4.0) assumes that the GWP for CH4 is 25 (so emissions of 1 MT of CH4 are equivalent to emissions of 25 MT of CO2), and the GWP for N2O is 298, based on the Intergovernmental Panel on Climate Change ’s Fourth Assessment Report (IPCC 2007). The GWP values identified in CalEEMod were applied to the project.