A7B8A62D0D — Santee City Council, August 12, 2026 (part 1 of 3)

Final Environmental Impact Report
San Diego River Fire Hazard
Mitigation Program:

Fuels Treatment Plan Project
State Clearinghouse No. 2026020351
JULY 2026
Prepared for:

CITY OF SANTEE

FIRE DEPARTMENT
10601 Magnolia Avenue
Santee, California 92071
Prepared by:
687 South Coast Highway 101, Suite 110
Encinitas, California 92024

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Response to Comment Letter O1
San Diego County Archaeological Society, Inc.

James W Royle
June 16, 2026
O1-1 The comment is an introduction to the comments that follow. The comment does not raise a significant environmental issue regarding the accuracy or adequacy of the information provided in the Draft EIR.

Therefore, no further response is required.

O1-2 The comment agrees with the impact analysis and mitigation measures for cultural resources and provides a suggestion to include a new archaeological and Kumeyaay survey after moderate- or largearea fires of the fire-affected areas as such surveys could detect resources which were obscured or inaccessible at the time of the current survey and help guide future actions. The project is not proposing prescribed burning as part of the vegetative fuel reduction activities. Additionally, if a fire were to occur within the project site between the time of the survey and the implementation of fuel treatment activities MM-CUL-2 includes cultural resources monitoring with an archaeological monitor and Kumeyaay Native American monitor during on site initial ground disturbing activities which is intended to address inadvertent disturbance to cultural resources during project implementation, therefore, revisions to the mitigation measures are not warranted. Surveying of the project site after fires is not within the scope of the project. MM-CUL-2 would adequately address any exposed resources as a result of a fire prior to project implementation.

O1-3 The comment states that the earlier 1928-29 Tax Factor aerial photographs were not inspected. While it does not affect the mitigation measures recommended, they should have been included in the research. Dudek’s 2026 Cultural Resources Inventory Report (Appendix D) contains a section on the review of historic maps and aerials, which included a review of historic aerial photographs from 1953 through 2022, and historic topographic maps from 1893 through 2021. It is unlikely that review of the 1928-29 “Tax Factor” aerial photographs referenced would have the potential to reveal new relevant information or previously unrecorded resources not already known through review of the aerial photographs, topographic maps, and records from the South Coastal Information Center, as the earliest topographic map available is from 1893, which is earlier than the 1928-29 “Tax Factor” aerial photo series. Through this research, the Cultural Resources Assessment Report and its review of historic aerial photographs/topographic maps are considered sufficiently adequate for the purposes of identifying the project’s potential historic resources impacts. A review of the 1828-29 “Tax Factor” aerial photo series and revisions to the Cultural Resources Assessment Report (Appendix D) and the DEIR are not warranted.

O1-4 The comment is a conclusory remark. The comment does not raise a significant environmental issue regarding the accuracy or adequacy of the information provided in the Draft EIR. Therefore, no further response is required.

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Response to Comment Letter L1
County of San Diego
Mike Madrid, AICP, Group Program Manager
June 22, 2026
L1-1 The comment provides an introduction to the comments that follow. The comment does not raise a significant environmental issue regarding the accuracy or adequacy of the information provided in the Draft EIR. Therefore, no further response is required.

L1-2 The comment states that project impacts that could have potentially significant adverse effects to the unincorporated County or County facilities should be evaluated using the County’s Guidelines for Determining Significance. The City acknowledges this comment. While parcels included as part of the proposed project are owned by the County, the parcels are located within the City of Santee and are not considered unincorporated County of San Diego. Therefore, County standards of significance were not used to evaluate the project’s potentially significant impacts. Further, as concluded in the Draft EIR, all impacts would be mitigated to less than significant.

LI-3 The comment introduces the Department of Environmental Health and Quality and is an introduction to the comments that follow. The comment does not raise a significant environmental issue regarding the accuracy or adequacy of the information provided in the Draft EIR. Therefore, no further response is required.

LI-4 The comment provides information regarding the Hazardous Materials Business Plan, and states that the project could result in facilities that store and/or handle 55 gallons or more of hazardous materials and/or generate any amount of hazardous waste or medical waste, and states that proposed activities involving the storage and handling of hazardous materials would require contractors to comply with local and state laws and regulations. The Project does not propose a facility that would store and/or handle hazardous materials, rather, the Project proposes the fuels treatment plan for the San Diego River Corridor in the City of Santee. The Draft EIR acknowledges the use and handling of hazardous materials in Draft EIR Section 4.3 and would comply with all local and state regulations that are applicable to the Project. The Project includes best management practices (BMPs) that are incorporated into the Project design to reduce the potential for hazardous materials to create hazards during routine handling during treatment and maintenance activities. The comment does not raise a significant environmental issue regarding the accuracy or adequacy of the information provided in the Draft EIR. Therefore, no further response is required.

L1-5 The comment provides information on hazardous waste requirements. The City acknowledges this comment. The project would comply with all local and state regulations that are applicable to the Project related to hazardous waste. The Project includes best management practices (BMPs) that are incorporated into the Project design to reduce the potential for hazardous materials to create hazards during routine handling during treatment and maintenance activities. The comment does not raise a significant environmental issue regarding the accuracy or adequacy of the information provided in the Draft EIR. Therefore, no further response is required.

L1-6 The comment provides information on regulations regarding aboveground petroleum storage. The City acknowledges this comment. The project would comply with all local and state regulations that are

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applicable to the Project related to petroleum storage. The comment does not raise a significant environmental issue regarding the accuracy or adequacy of the information provided in the Draft EIR.

Therefore, no further response is required.

L1-7 The comment provides information on regulations regarding unanticipated discovery of underground storage tanks. The City acknowledges this comment. The comment does not raise a significant environmental issue regarding the accuracy or adequacy of the information provided in the Draft EIR.

Therefore, no further response is required.

L1-8 The comment provides information regarding handling contaminated soil. The Project includes best management practices (BMPs) that are incorporated into the Project design to reduce the potential for hazardous materials to create hazards during routine handling during treatment and maintenance activities. The comment does not raise a significant environmental issue regarding the accuracy or adequacy of the information provided in the Draft EIR. Therefore, no further response is required.

L1-9 The comment states that Hazardous Materials Division has the authority to regulate facilities that handle or store hazardous materials and/or generate hazardous/medical waste. The City acknowledges this comment. The comment does not raise a significant environmental issue regarding the accuracy or adequacy of the information provided in the Draft EIR. Therefore, no further response is required.

L1-10 The comment introduces the Department of General Services and is an introduction to comments that follow. The comment does not raise a significant environmental issue regarding the accuracy or adequacy of the information provided in the Draft EIR. Therefore, no further response is required.

L1-11 The comment requests that the entirety of APN: 381-050-77-00 is included in Project boundary, rather than the portion of the parcel that is currently part of the Project, stating that inclusion of the parcel would help to support County and City of Santee joint efforts implementing the San Diego Riverbed Encampment Resolution Fund grant program. The City acknowledges this comment, however, the parcel is not part of the Project. The comment does not raise a significant environmental issue regarding the accuracy or adequacy of information provided in the Draft EIR. Therefore, no further response is required.

L1-12 The comment states that the County must authorize implementation of the Project on County-owned and managed land. The City will acquire any approvals and permits from the County prior to any fuel treatment on County-owned lands that are required to implement the Project. Section 3.7 of the Final EIR has been updated to reflect this comment. A Right of Entry permit has been drafted bythe City of Santee Fire Department and will be finalized upon approval of Phase 2 of the Grant.

L1-13 The comment is a conclusory remark. The comment does not raise a significant environmental issue regarding the accuracy or adequacy of the information provided in the Draft EIR. Therefore, no further response is required.

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Response to Comment Letter I1
Individual
Jennifer Webb
6/3/2026
I1-1 The comment expresses concern regarding three city trees that encroach the commenter’s home. The City acknowledges this comment. The Draft EIR evaluates environmental impacts associated with the proposed project, which does not include the city trees discussed in this comment. However, maintenance of the trees referenced in the comment was conducted by the City of Santee’s Public Services Division after the City received the comment. The comment does not raise a significant environmental issue regarding the accuracy or adequacy of the information provided in the Draft EIR.

Therefore, no further response is required.

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Table of Contents
SECTION PAGE NO.

Acronyms and abbreviations...................................................................................................................................... ACR-i 1 Executive Summary.......................................................................................................................................... 1-1

1.1 Introduction......................................................................................................................................... 1-1

1.2 Project Purpose .................................................................................................................................. 1-1

1.3 Project Location.................................................................................................................................. 1-2

1.4 Project Description ............................................................................................................................. 1-2

1.5 Best Management Practices.............................................................................................................. 1-4

1.6 Project Objectives............................................................................................................................... 1-4

1.7 Required Project Approvals................................................................................................................ 1-4

1.8 Summary of Impacts .......................................................................................................................... 1-5

1.9 Alternatives to the Project................................................................................................................1-29

1.10 Areas of Controversy/Issues to Be Resolved..................................................................................1-29 2 Introduction ...................................................................................................................................................... 2-1

2.1 Purpose of the California Environmental Quality Act Process ......................................................... 2-1

2.2 Legal Authority and Lead Agency....................................................................................................... 2-1

2.3 Responsible and Trustee Agencies ................................................................................................... 2-2

2.4 Summary of Project Analyzed in this Environmental Impact Report............................................... 2-3

2.5 Scope of Environmental Analysis ...................................................................................................... 2-3

2.5.1 Notice of Preparation Scoping Process ............................................................................... 2-3

2.5.2 Environmental Effects Found Not to Be Significant............................................................ 2-5

2.5.3 Environmental Issues Determined to be Potentially Significant........................................ 2-5

2.6 Organization of this Environmental Impact Report .......................................................................... 2-5

2.7 Documents Incorporated by Reference ............................................................................................ 2-7

2.8 Review of the Draft Environmental Impact Report........................................................................... 2-8 3 Project Description........................................................................................................................................... 3-1

3.1 Introduction......................................................................................................................................... 3-1

3.2 Project Location.................................................................................................................................. 3-1

3.3 Environmental Setting........................................................................................................................ 3-1

3.3.1 City of Santee........................................................................................................................ 3-1

3.3.2 Existing Project Site .............................................................................................................. 3-2

3.3.3 Wildfire Environment ............................................................................................................ 3-9

3.4 Project Objectives.............................................................................................................................3-13

3.5 Fuels Treatment Plan .......................................................................................................................3-13

3.6 Best Management Practices............................................................................................................3-19

3.7 Required Project Approvals..............................................................................................................3-25

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4 Environmental Analysis.................................................................................................................................... 4-1

4.1 Biological Resources .......................................................................................................................4.1-1

4.1.1 Existing Conditions.............................................................................................................4.1-1

4.1.2 Relevant Plans, Policies, and Ordinances......................................................................4.1-49

4.1.3 Thresholds of Significance ..............................................................................................4.1-58

4.1.4 Impact Analysis ................................................................................................................4.1-59

4.1.5 Mitigation Measures and Level of Significance After Mitigation ..................................4.1-77

4.2 Cultural and Tribal Cultural Resources ..........................................................................................4.2-1

4.2.1 Existing Conditions.............................................................................................................4.2-1

4.2.2 Relevant Plans, Policies, and Ordinances........................................................................4.2-5

4.2.3 Thresholds of Significance ..............................................................................................4.2-11

4.2.4 Impact Analysis ................................................................................................................4.2-12

4.2.5 Mitigation Measures and Level of Significance After Mitigation .................................4.2-14

4.3 Hazards and Hazardous Materials .................................................................................................4.3-1

4.3.1 Existing Conditions.............................................................................................................4.3-1

4.3.2 Relevant Plans, Policies, and Ordinances........................................................................4.3-4

4.3.3 Thresholds of Significance ..............................................................................................4.3-14

4.3.4 Impact Analysis ................................................................................................................4.3-15

4.3.5 Mitigation Measures and Level of Significance After Mitigation ..................................4.3-20

4.4 Hydrology and Water Quality...........................................................................................................4.4-1

4.4.1 Existing Conditions.............................................................................................................4.4-1

4.4.2 Relevant Plans, Policies, and Ordinances........................................................................4.4-5

4.4.3 Thresholds of Significance ................................................................................................4.4-9

4.4.4 Impact Analysis ................................................................................................................4.4-10

4.4.5 Mitigation Measures and Level of Significance After Mitigation ..................................4.4-12

4.5 Noise ................................................................................................................................................4.5-1

4.5.1 Existing Conditions.............................................................................................................4.5-1

4.5.2 Relevant Plans, Policies, and Ordinances........................................................................4.5-3

4.5.3 Thresholds of Significance ................................................................................................4.5-6

4.5.4 Impact Analysis ..................................................................................................................4.5-6

4.5.5 Mitigation Measures and Level of Significance After Mitigation ..................................4.5-10

4.6 Wildfire .............................................................................................................................................4.6-1

4.6.1 Existing Conditions.............................................................................................................4.6-1

4.6.2 Relevant Plans, Policies, and Ordinances........................................................................4.6-3

4.6.3 Thresholds of Significance ................................................................................................4.6-8

4.6.4 Impact Analysis ..................................................................................................................4.6-9

4.6.5 Mitigation Measures and Level of Significance After Mitigation ..................................4.6-13 5 Effects Found Not to Be Significant................................................................................................................ 5-1

5.1 Aesthetics ........................................................................................................................................... 5-1

5.2 Agricultural and Forestry Resources ................................................................................................. 5-2 EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN JULY 2026

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5.3 Air Quality ............................................................................................................................................ 5-2

5.4 Energy ................................................................................................................................................. 5-3

5.5 Geology and Soils ............................................................................................................................... 5-3

5.6 Greenhouse Gas Emissions............................................................................................................... 5-4

5.7 Land Use and Planning ...................................................................................................................... 5-4

5.8 Mineral Resources ............................................................................................................................. 5-5

5.9 Population and Housing..................................................................................................................... 5-5

5.10 Public Services ................................................................................................................................... 5-5

5.11 Recreation........................................................................................................................................... 5-6

5.12 Transportation .................................................................................................................................... 5-6

5.13 Utilities and Service Systems............................................................................................................. 5-7 6 Other CEQA Considerations............................................................................................................................. 6-1

6.1 Cumulative Impacts............................................................................................................................ 6-1

6.1.1 Cumulative Impact Analysis ................................................................................................. 6-5

6.2 Growth-Inducing Impacts .................................................................................................................6-17

6.3 Significant Irreversible Changes......................................................................................................6-18

6.3.1 Change in Land Use that Commits Future Generations to Similar Uses.........................6-18

6.3.2 Irreversible Damage from Environmental Accidents ........................................................6-18

6.3.3 Large Commitment of Nonrenewable Resources.............................................................6-19

6.4 Significant and Unavoidable Impacts..............................................................................................6-19 7 Alternatives....................................................................................................................................................... 7-1

7.1 Alternatives to the Proposed Project................................................................................................. 7-1

7.2 Considerations for Selection of Alternatives..................................................................................... 7-2

7.3 Project Alternatives Considered and Rejected ................................................................................. 7-4

7.4 Project Alternatives Under Further Consideration ............................................................................... 7-5

7.4.1 No Project (Alternative 1) ..................................................................................................... 7-5

7.4.2 Zone 3 Standards Alternative (Alternative 2)......................................................................... 7-7

7.4.3 Manual and Mechanical Treatment (Alternative 3) ............................................................... 7-9

7.5 Environmentally Superior Alternative..............................................................................................7-12 8 List of Preparers............................................................................................................................................... 8-1

8.1 Report Preparers ................................................................................................................................ 8-1 9 References ....................................................................................................................................................... 9-1 Chapter 1: Executive Summary ....................................................................................................................... 9-1 Chapter 2: Introduction.................................................................................................................................... 9-1 Chapter 3: Project Description ........................................................................................................................ 9-1 Chapter 4: Environmental Analysis ................................................................................................................. 9-1 Section 4.1: Biological Resources..................................................................................................... 9-2 Section 4.2: Cultural, Tribal Cultural, Paleontological Resources ................................................... 9-3 Section 4.3: Hazards and Hazardous Materials............................................................................... 9-3 EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN JULY 2026

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Section 4.4: Hydrology and Water Quality ........................................................................................ 9-3 Section 4.5: Noise .............................................................................................................................. 9-4 Section 4.6: Wildfire........................................................................................................................... 9-5 Chapter 5: Effects Not Found To Be Significant............................................................................................. 9-6 Chapter 6: Other CEQA Considerations .......................................................................................................... 9-7 Chapter 7: Alternatives .................................................................................................................................... 9-7 Chapter 8: List of Preparers ............................................................................................................................ 9-7

FIGURES
3-1 Regional Location ............................................................................................................................................ 3-3 3-2 Project Location ............................................................................................................................................... 3-5 3-3 Parcel Ownership ............................................................................................................................................. 3-7 3-4 Fire Hazard Severity Zones............................................................................................................................3-11 3-5 Treatment Zones............................................................................................................................................3-15 3-6 Access Routes ................................................................................................................................................3-21

4.1-1A Biological Resources.....................................................................................................................................4.1-3

4.1-1B Biological Resources.....................................................................................................................................4.1-5

4.1-1C Biological Resources.....................................................................................................................................4.1-7

4.1-1D Biological Resources.....................................................................................................................................4.1-9

4.1-1E Biological Resources...................................................................................................................................4.1-11

4.1-2A Suitable Special-Status Plant Habitats......................................................................................................4.1-17

4.1-2B Suitable Special-Status Plant Habitats......................................................................................................4.1-19

4.1-2C Suitable Special-Status Plant Habitats......................................................................................................4.1-21

4.1-2D Suitable Special-Status Plant Habitats......................................................................................................4.1-23

4.1-2E Suitable Special-Status Plant Habitats......................................................................................................4.1-25

4.1-3A Suitable Special-Status Wildlife Habitats ..................................................................................................4.1-35

4.1-3B Suitable Special-Status Wildlife Habitats ..................................................................................................4.1-37

4.1-3C Suitable Special-Status Wildlife Habitats ..................................................................................................4.1-39

4.1-3D Suitable Special-Status Wildlife Habitats ..................................................................................................4.1-41

4.1-3E Suitable Special-Status Wildlife Habitats ..................................................................................................4.1-43

4.1-4 Wildlife Corridors and Habitat Linkages ....................................................................................................4.1-45

4.1-5 Potentially Jurisdictional Aquatic Resources.............................................................................................4.1-47

4.1-6 MSCP Lands ................................................................................................................................................4.1-51

4.1-7A Impacts to Biological Resources ................................................................................................................4.1-65

4.1-7B Impacts to Biological Resources ................................................................................................................4.1-67

4.1-7C Impacts to Biological Resources ................................................................................................................4.1-69

4.17-D Impacts to Biological Resources ................................................................................................................4.1-71 EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN JULY 2026

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4.17-E Impacts to Biological Resources ................................................................................................................4.1-73

4.4-1 Flood Hazard Map.........................................................................................................................................4.4-3 TABLES
1-1 Summary of Project Impacts ........................................................................................................................... 1-6 1-2 Summary of Notice of Preparation Comments.............................................................................................1-30 2-1 Summary of Notice of Preparation Comments............................................................................................... 2-4

3.1 Parcel Ownership ............................................................................................................................................. 3-2

3.2 Acreage of Treatment Zones .........................................................................................................................3-17

4.1-1 Vegetation Communities and Land Covers Within the Project Site ...........................................................4.1-2

4.1-2 Special-Status Plant Species Present or with a Moderate to High Potential to Occur on the Project Site.................................................................................................................................. 14

4.1-3 Special-Status Wildlife Present, Considered Present, or with a Moderate to High Potential to Occur on the Project Site........................................................................................................4.1-28

4.1-4 Potential Jurisdictional Aquatic Resources Within the Project Site .........................................................4.1-34

4.1-5 Vegetation Communities and Land Cover Types in Zones 1 and 2................................................................4.1-62

4.1-6 Plant Species Identified for Treatment or Removal in Zone 3 .................................................................4.1-63

4.1-7 Potentially Jurisdictional Aquatic Resources Within Zones 1 and 2........................................................4.1-75

4.5-1 Typical Sound Levels in the Environment and Industry ..............................................................................4.5-2

4.5-2 Equipment by Vegetation Management Activity..........................................................................................4.5-7

4.5-3 Typical Construction Equipment Maximum Noise Levels...........................................................................4.5-7 6-1 Geographic Scope of Cumulative Impact Analyses........................................................................................ 6-2 6-2 Cumulative Project List.................................................................................................................................... 6-2 7-1 Project Alternatives Environmental Impacts Comparison ...........................................................................7-12

APPENDICES
A NOP and Public Comments
B Biolgical Resources Letter Report
C Built Environment Area of Potential Effects (APE) memorandum D Cultural Resource Assessment Report
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Acronyms and Abbreviations
Acronym/Abbreviation Definition
AB Assembly Bill
AIA airport influence area
ALUCP Airport Land Use Compatibility Plan
ANSI American National Standards Institute
APE Area of Potential Effects
Basin Plan Water Quality Control Plan for the San Diego Basin BMP best management practice
CAL FIRE California Department of Forestry and Fire Protection CalARP California Accidental Release Prevention Program CalEPA California Environmental Protection Agency
CalGEM California Geologic Energy Management
Caltrans California Department of Transportation
CCR California Code of Regulations
CDFW California Department of Fish and Wildlife
CEQA California Environmental Quality Act
CESA California Endangered Species Act
CFC California Fire Code
CFR Code of Federal Regulations
CGP Construction General Permit
CHRIS California Historical Resources Information System City City of Santee
CNEL Community Noise Equivalent Level
County County of San Diego
CRHR California Register of Historic Resources
CRPR California Rare Plant Rank
CWA Clean Water Act
dB decibel
dBA A-weighted decibel
DTSC Department of Toxic Substance Control
DTSC-SL Department of Toxic Substance Control–modified screening level EIR Environmental Impact Report
EOP Emergency Operations Plan
EPA U.S. Environmental Protection Agency
ESA Environmentally Sensitive Area
FESA federal Endangered Species Act
FHSZ Fire Hazard Severity Zone

ACRONYMS AND ABBREVIATIONS
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Acronym/Abbreviation Definition
FTA Federal Transit Administration
FTP Fuels Treatment Plan
GHG greenhouse gas
HCP habitat conservation plan
HERO Human and Ecological Risk Office
HMTA Hazardous Materials Transportation Act
HSC California Health and Safety Code
IFC International Fire Code
ips inch per second
ISA International Society of Arboriculture
Ldn day–night average noise level
Leq equivalent noise level over a given period
Lmax maximum sound level recorded during the measurement interval MJHMP Multi-Jurisdictional Hazard Mitigation Plan
MHPA Multi-Habitat Planning Area
MLD most likely descendant
MM Mitigation Measure
mph miles per hour
MS4 Municipal Separate Storm Sewer
MSCP Multiple Species Conservation Program
NAHC Native American Heritage Commission
NEPA National Environmental Policy Act
NESHAP National Emission Standards for Hazardous Air Pollutants NOP Notice of Preparation
NPDES National Pollutant Discharge Elimination System
NRHP National Register of Historic Places
OSHA Occupational Safety and Health Administration
Porter–Cologne Act Porter–Cologne Water Control Quality Act PCA pest control adviser
PCB polychlorinated biphenyl
PPV peak particle velocity
PRC Public Resources Code
Project
San Diego River Fire Hazard Mitigation Program: Fuels Treatment Plan Project
RCRA Resource Conservation and Recovery Act
RSL regional screening level
RWQCB Regional Water Quality Control Board
SDAPCD San Diego County Air Pollution Control District
SFD Santee Fire Department

ACRONYMS AND ABBREVIATIONS
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Acronym/Abbreviation Definition
SLF Sacred Lands File
SR State Route
SWRCB State Water Resources Control Board
TCR Tribal Cultural Resource
TMDL total maximum daily load
USACE U.S. Army Corps of Engineers
USDOT U.S. Department of Transportation
USFWS U.S. Fish and Wildlife Service
WDR waste discharge requirement
WUI wildland–urban interface

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1 Executive Summary

1.1 Introduction
This Environmental Impact Report (EIR) has been prepared by the City of Santee (City) as lead agency pursuant to the California Environmental Quality Act (CEQA). This EIR has been prepared to evaluate the environmental impacts associated with implementation of the San Diego River Fire Hazard Mitigation Program: Fuels Treatment Plan (Project).

This EIR is an informational document intended for use by the City, other public agencies, and members of the public in evaluating the potential environmental effects of the Project.

CEQA requires that local government agencies, before taking action on projects over which they have discretionary approval authority, consider the environmental consequences of such projects. An EIR is a document designed to provide to the public and to local and state governmental agency decision makers an analysis of potential environmental consequences of a project to support informed decision making.

The City prepared this EIR to provide the public and responsible agencies information about the potential adverse impacts on the local and regional environment associated with implementation of the Project. This EIR was prepared pursuant to CEQA, codified as California Public Resources Code Section 21000 et seq., and the CEQA Guidelines in the California Code of Regulations, Title 14, Section 15000 et seq. 1 This summary provides a brief synopsis of the Project, the results of the environmental analysis contained within this environmental document, alternatives to the Project that were considered, and major areas of interest and issues to be resolved by decision makers. This summary does not contain the extensive background and analysis found throughout the individual chapters within the EIR. Therefore, the reader should review the entire document to fully understand the Project and its environmental effects.

1.2 Project Purpose
The City of Santee Fire Department has initiated the development of the San Diego River Fire Hazard Mitigation Program: Fuels Treatment Plan (FTP) to reduce wildfire risk in and around high-priority sites along the San Diego River corridor. This area lies within the wildland–urban interface and includes critical public infrastructure, adjacent residential neighborhoods, and biologically sensitive habitats. The need for a targeted, ecologically conscious approach to vegetation management is underscored by increasing fire risk, invasive plant encroachment, and complex access and ownership constraints unique to the corridor.

The FTP provides a framework for vegetation management across the approximately 300-acre Project Site and includes treatment strategies tailored to the Project Site’s wildfire exposure, access conditions, existing vegetation, and proximity to sensitive resources. The plan is designed to protect communities, critical infrastructure, and sensitive resources by reducing wildfire risk through coordinated vegetation management across the Project Site. The FTP is designed to balance fire risk reduction with environmental stewardship. It 1 Federal environmental compliance has been initiated utilizing the following Programmatic Environmental Assessment:
https://www.fema.gov/sites/default/files/2020-09/fema_final-programmatic-environmental-assessmentrecurring-activities-in-arizona-california-nevada_12012014.pdf. 1 – EXECUTIVE SUMMARY
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emphasizes selective vegetation modification techniques that support defensible space and risk reduction while preserving ecological function, minimizing soil disturbance, and protecting sensitive resources.

1.3 Project Location
The approximately 300-acre Project Site is a total of 33 parcels composed of 29 distinct parcels and four (4) portions of rights-of-way 299.9-acre Project Site is located within 332 parcels along the San Diego River corridor that cuts through the center of the City of Santee as shown in Figure 3-1, Regional Location, and Figure 3-2, Project Location. The Project Site is located within Township 15 South, Range 1W, Sections 21, 22, 23, 27, 28, and 29 of the El Cajon and La Mesa, California 7.5-minute U.S. Geological Survey Quadrangle maps. The Project Site extends from Forester Creek at the western Project boundary to the City border with the unincorporated Lakeside community in the east, including the open space areas of Mast Park West, Mast Park Wetland Restoration Area, Mast Park East, Mission Creek, Walker Trails Open Space, and Walker Preserve. Vehicular access to the Project Site is via North Magnolia Avenue, the Lakeside Sports Park and Mast Park. Multiple pedestrian access paths, residential and commercial developments border the Project.

1.4 Project Description
The Project is the implementation of the San Diego River Fire Hazard Mitigation Program: Fuels Treatment Plan, which proposes fuel treatment and vegetation management in the Project Site. The Fuels Treatment Plan provides a framework for vegetation management across the approximately 300-acre Project Site and includes treatment strategies tailored to the Project Site’s wildfire exposure, access conditions, existing vegetation, and proximity to sensitive resources. The plan is designed to protect communities, critical infrastructure, and sensitive resources by reducing wildfire risk through coordinated vegetation management across the Project area. The Fuels Treatment Plan is designed to balance fire risk reduction with environmental stewardship. It emphasizes selective vegetation modification techniques that support defensible space and risk reduction while preserving ecological function, minimizing soil disturbance, and protecting sensitive resources.

Vegetation management recommendations for the Project Site are organized into three zones. Each zone provides a framework to reduce fuel continuity while protecting the hydrologic, ecological, and recreational functions of the river corridor. In each zone, vegetation management consists overall of the removal of all fine fuels, leaf litter, woody debris, treating or removing all non-native and dead vegetation including invasive species and shrubs or trees with extensive dead or desiccated material, and treatment or removal of accumulations deposited during storm events.

Zone 1
Zone 1 encompasses the 0- to 50-foot area immediately adjacent to structures and represents the highest priority for reducing direct flame contact, radiant heat exposure, and ember ignition. Vegetation management in this zone focuses on eliminating combustible materials, disrupting fuel continuity, and minimizing ignition pathways to buildings.

Throughout Zone 1, all fine fuels, dead vegetation, leaf litter, and woody debris would be treated or removed. Grasses would be trimmed/mowed to a height not to exceed 4 inches. Shrubs would be thinned to reduce horizontal continuity to a residual surface coverage of approximately 30%. Shrubs or other surface vegetation (e.g., ground cover) would 2 Some of the Project parcels overlap due to differences in ownership. 1 – EXECUTIVE SUMMARY
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be treated to reduce vertical continuity beneath tree canopies to achieve a separation of three times the height of the surface vegetation. Non-native, invasive, or flammable plant species would be removed wherever present. Ladder fuels would also be addressed by pruning low tree branches (in addition to treating shrubs or surface vegetation beneath tree canopies). All trimming activities would be done to industry standards (International Society of Arboriculture, American National Standards Institute) to minimize likelihood of plant death. In addition, clearance would be maintained around fences, propane tanks, accessory structures, and other features susceptible to ignition, as applicable. Live and healthy native species may be treated as allowed through additional permitting only.

Zone 2
Zone 2 encompasses the 50- to 100-foot area, which lies beyond the immediate structure buffer and provides an intermediate level of fuel reduction intended to moderate fire behavior as it approaches developed parcels. This zone generally includes landscaped edges and transitional areas between riparian vegetation and upland shrublands or grasslands.

Vegetation management in Zone 2 consists of treating or removing all non-native and dead vegetation, including invasive species and shrubs or trees with extensive dead or desiccated material, pruning dead and dying branches from native vegetation to reduce ladder fuels and minimizing the potential for tree canopy torching. Shrubs would be thinned to reduce horizontal continuity to a residual surface coverage of approximately 50%. Shrubs or other surface vegetation (e.g., ground cover) would be treated to reduce vertical continuity beneath tree canopies to achieve a separation of three times the height of the surface vegetation. Grasses would be trimmed/mowed to a height not to exceed 4 inches. All trimming activities would be done to industry standards (International Society of Arboriculture, American National Standards Institute) to minimize likelihood of plant death. Vegetation removal and treatment in this zone is intended to reduce fire intensity and rate of spread while maintaining ecological structure where feasible. Live and healthy native species may be treated as allowed through additional permitting only.

Zone 3
Zone 3 encompasses the broader vegetated areas of the river corridor (outside Zones 1 and 2), including most riparian zones, floodplain terraces, and open space areas such as portions of Mast Park and Walker Preserve.

Treatments in this zone focus on reducing hazardous, non-native vegetation while preserving riparian canopy, hydrologic function, and recreational access. Vegetation management in Zone 3 is focused on treatment or removal of non-native species, dead or dying vegetation, and debris, including accumulations deposited during storm events.

Removal and other treatment of live and healthy native species would not occur within Zone 3.

Biomass Removal
Biomass removal would depend on the type of treatment proposed. Methods available for biomass removal include off-site transportation to a green waste facility, on-site broadcast of chips, lop- and scatter (crews cut material into shorter lengths and scatter it evenly, so it lies as close to the ground as possible), cranes and helicopters and species-specific disposal (for invasive or weed species). Disposal approach would depend on access, vegetation type, and the volume of material generated. Off-site removal shall be prioritized where feasible due to its long-term hazard reduction benefits. Chipping may be used where equipment access is available, and vegetation consists of suitable woody material. Lop-and-scatter shall be limited to small, constrained areas. 1 – EXECUTIVE SUMMARY
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Access and Staging
Access to the Project Site would vary during Project implementation. During Project implementation, routes would be confirmed by the vegetation management contractor prior to use. Some access routes would require rights of entry based on land ownership.

Maintenance
The Project includes the maintenance of the Project Site for 4 years to ensure that initial vegetation treatments continue to reduce wildfire hazard over time. The City will be responsible for conducting biannual inspections, determining maintenance needs for each zone, coordinating or engaging maintenance crews, and ensuring compliance with the FTP. Maintenance intervals will vary depending on vegetation type, treatment zone, and treatment technique.

1.5 Best Management Practices
Project-specific Best Management Practices (BMPs) were developed in conjunction with the FTP and will be implemented as part of the proposed Project. BMPs are identified by treatment type (hand labor, mechanical equipment, chemical use) and environmental issue area (slope stability/erosion, water quality, pests and pathogens, fire protection, air quality, recreation resources, noise, and biological resources). These BMPs are listed in Section 3.6, Best Management Practices, of this EIR.

1.6 Project Objectives
Consistent with the Project’s purpose and need, the primary objectives sought by the Project are as follows:

Objective 1 – Define strategy for specific fuel treatment zones for reducing hazardous fuel loads within the San Diego River corridor.

Objective 2 – Enhance community safety within the City of Santee through the reduction of wildfire risk.

Objective 3 – Reduce horizontal and vertical continuity of fuels and hazardous fuel loads through the removal of non-native and invasive species.

Objective 4 – Reduce ignition potential and fire intensity within the San Diego River corridor.

1.7 Required Project Approvals
This EIR covers all state and local government and quasi-government approvals that may be needed to implement the Project, whether or not they are explicitly listed in this section or elsewhere in this EIR (14 CCR 15124[d]).

Regulatory and environmental compliance for the Project will include coordination and consultation with several 1 – EXECUTIVE SUMMARY
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state and federal agencies to issue all required permissions for the Project, as well as review and approval by the City Council in accordance with the City’s General Plan and Municipal Code.

City Council
▪ Consideration of the San Diego River Hazard Mitigation Program: Fuels Treatment Plan. The City Council will consider whether to adopt, revise, or reject the San Diego River Fire Hazard Mitigation Program: Fuels Treatment Plan.
▪ Consideration of EIR. The City Council will consider whether to certify or reject this EIR, along with appropriate CEQA findings and the mitigation monitoring and reporting program.

1.8 Summary of Impacts
Table 1-1 presents a summary of the Project’s significant environmental impacts and mitigation measures that would reduce or avoid those effects, and the level of significance of the impact after implementation of the mitigation measures. With the exception of those specific impacts identified in Table 1-1, the Project would result in less-than-significant or no impacts with regard to all other resource areas evaluated. Cumulative impacts of the Project were evaluated in Section 6.1, Cumulative Impacts, of the Draft EIR. For cumulative impacts that would not be significant, the cumulative impacts and their conclusions are not included in Table 1-1. For areas where the cumulative impacts would be potentially significant and would require mitigation, these impacts, mitigation measures, and conclusions are included in Table 1-1.
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Table 1-1. Summary of Project Impacts
Environmental Topic Impact? Mitigation Measures
Level of
Significance
After Mitigation
Biological Resources
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 Game
or U.S. Fish and Wildlife
Service?
Potentially
significant
impact
MM BIO-1 Pre-Construction Survey and Special-Status Plant Species Avoidance.

No vegetation management activities occurring in Zone 3 or other native and non-native brush thinning occurring in Zones 1 and 2 shall occur within known populations of San Diego marsh-elder and white rabbit-tobacco or any other special-status plant species. Prior to initiation of Project activities, a qualified biologist (i.e., a person having at minimum a BS or BA in wildlife management, ecology, zoology, botany, biology, or other closely related field, and at least 2 years’ experience conducting field investigations in San Diego County) approved by the City of Santee shall conduct a pre-construction presence/absence survey for special-status plants within the impact footprint and flag any special-status plants, including the known locations of San Diego marsh-elder and white rabbittobacco. . If surveys are conducted pursuant to the FEMA Programmatic Biological Opinion for federally listed plant species, the qualified biologist shall be approved by the Carlsbad Fish and Wildlife Office (CFWO) in accordance with Gen AMM 16. If a special-status plant is observed, the biological monitor shall delineate an appropriate buffer zone (a minimum of 10 feet) depending on the sensitivity of the resource and the nature of the activity being conducted. Project activities shall completely avoid impacts to any special-status plant species.

MM BIO-2 Standard Best Management Practices (BMPs). The following BMPs, when applicable, shall be included as part of the Project in accordance with Section 5.5.1.1 of the Draft Santee Multiple Species Conservation Program Subarea Plan (City of Santee 2025). The City of Santee shall have the right to access and inspect any treatment sites for compliance with Project approval conditions including these BMPs.
▪ Delineation of Environmentally Sensitive Areas
▪ Prior to Project implementation, highly visible barriers (such as orange construction fencing, stakes, or flagging depending on the size of the treatment area and the sensitivity and proximity of the biological resources) shall be installed to designate environmentally sensitive areas (e.g., specialstatus plant locations, nesting birds, etc.) to be protected from vegetation management related activities. Environmentally sensitive areas to be Less-thansignificant impact
with mitigation
incorporated
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Table 1-1. Summary of Project Impacts
Environmental Topic Impact? Mitigation Measures
Level of
Significance
After Mitigation
avoided shall be identified during the pre-construction surveys described in MM BIO-1 and MM BIO-3 and implemented by a qualified biologist approved by the City of Santee. No Project activity of any type shall be permitted within these environmentally sensitive areas (with exceptions for removal of dead/decaying and non-native species within jurisdictional aquatic resource areas in Zone 3). In addition, heavy equipment, including motor vehicles, shall not be allowed to operate within the environmentally sensitive areas.

All vegetation management equipment shall be operated in a manner so as to prevent accidental damage to environmentally sensitive areas and associated barriers. No structure of any kind, equipment staging, incidental storage of equipment or supplies, or access roads shall be allowed within these protected zones. Silt fence barriers shall be installed, as appropriate, at the environmentally sensitive area boundary to prevent accidental deposition of fill material or sediment runoff into areas where sensitive biological features are adjacent to treatment areas. Flagging and/or fencing shall be removed upon completion of the activities.
▪ Invasive Species Control
▪ Invasive exotic plant species shall be removed from the Project work area and controlled during vegetation management periods. Project measures shall be included to ensure invasive plant material is not spread from the Project Site to other areas by disposal off site or by tracking seed on equipment, clothing, and shoes. Equipment/material imported from an area of invasive plants must be identified and measures implemented to prevent importation and spreading of non-native plant material within the Project Site. Disposal of the plant debris shall follow the regulations set by the County of San Diego agriculture commissioner. All vegetation management equipment shall be cleaned to remove dirt, seeds, vegetative material, or other debris that could contain or hold seeds of noxious weeds before arriving to and leaving from the Project Site. Eradication strategies (i.e., exotic plant abatement programs) shall be employed should an invasion occur during vegetation management activities.
▪ Trash Control
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Table 1-1. Summary of Project Impacts
Environmental Topic Impact? Mitigation Measures
Level of
Significance
After Mitigation
▪ To avoid attracting predators of Covered Species and other special-status species, the Project Site shall be kept clean of debris. All food-related trash items shall be enclosed in sealed containers and regularly removed from the site(s) daily.
▪ On-Site Training and Monitoring
▪ All personnel involved in the on-site Project activities shall be required to participate in a pre-activity training and education program administered by the City, or their designee, to understand the avoidance and minimization obligations of the Project.
▪ The City shall require that a qualified biologist monitor Project activities for the duration of the Project to ensure that measures are being employed to avoid incidental disturbance of habitat, species of concern, and other sensitive biological resources. The biological monitor shall notify the City immediately of any non-compliance, and the City shall make an assessment that generates appropriate measures for the contractor to implement for remediation.
▪ Water Quality Best Management Practices
▪ The vegetation treatment contractors shall implement BMPs to protect water quality. To minimize soil disturbance, the vegetation treatment contractors shall leave stumps from removed trees and shrubs intact, with stump heights not exceeding 6 inches, as measured from the uphill side as described in the Fuels Treatment Plan (City of Santee 2026). ▪ Actions to prevent sediment or debris from entering watercourses, aquatic areas, wetlands, and riparian areas during and after Project activities may include, but are not limited to, the following BMPs: silt fencing, fiber rolls and other erosion control blankets, gravel bag berms, sand bag barriers, tracking controls, stockpile management, dry season scheduling, preservation of existing vegetation, temporary soil stabilization, dust and erosion control. ▪ No site personnel shall discharge solid or liquid materials into jurisdictional water features, wetland or riparian areas, or other sensitive habitats. Service and refueling of equipment shall only occur in areas that will not allow grease, oil, fuel, or other hazardous materials to pass into streams or EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN JULY 2026
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Table 1-1. Summary of Project Impacts
Environmental Topic Impact? Mitigation Measures
Level of
Significance
After Mitigation
retained vegetation. If discharged materials are observed during work activities, the biological monitor shall notify the City and appropriate entities immediately, including but not limited to applicable jurisdictional City or County, U.S. Fish and Wildlife Service, U.S. Army Corps of Engineers, California Department of Fish and Wildlife, and/or Regional Water Quality Control Board, and the City shall make an assessment that generates appropriate measures for the contractor to implement for remediation. Spills shall be cleaned up immediately and contaminated soils removed to approved disposal areas.

MM BIO-3 Biological Monitor. A qualified biological monitor (i.e., a person having at minimum a BS or BA in wildlife management, ecology, zoology, botany, biology, or other closely related field, and at least 2 years’ experience conducting field investigations in San Diego County) approved by the City of Santee shall be present to conduct a pre-activity sweep (i.e., pre-construction survey) of the work area prior to the commencement of work activities. Where monitoring is required pursuant to the FEMA Programmatic Biological Opinion for federally listed species, monitoring shall be conducted by or under the supervision of a CFWOapproved biologist in accordance with Gen AMM 16. The qualified monitor shall remain present during any Project activities in Zones 1 to 3 that occur in sensitive vegetation communities, as defined herein), to ensure no sensitive biological resources (i.e., sensitive vegetation communities, special-status species, and jurisdictional aquatic resources) are being adversely impacted from Project implementation in Zone 3 and that no special-status species or nesting birds are being adversely impacted from Project implementation in Zones 1 and

2. If a sensitive biological resource is observed during Project activities or during pre-construction surveys, the biological monitor shall delineate an appropriate buffer zone (a minimum of 10 feet) depending on the sensitivity of the resource and the nature of the activity being conducted.

If fencing for temporary noise abatement (i.e., 8-foot-tall [minimum height] plywood sheet barriers or acoustical blankets suspended on chain-link fencing or other support means) is required along or parallel with an extent of the Project boundary that adjoins the receiving noise-sensitive property then prior to the use of temporary noise abatement, a qualified biologist shall confirm and verify with EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN JULY 2026
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Table 1-1. Summary of Project Impacts
Environmental Topic Impact? Mitigation Measures
Level of
Significance
After Mitigation
the City that the placement of the barriers are not located within any environmentally sensitive areas (e.g., special-status plant locations, sensitive vegetation communities, or jurisdictional aquatic resources) and would not impact any wildlife species or their movement.

A restoration plan will be prepared for and approved by the City, and depending on the area affected any other appropriate regulatory agency (i.e. USFWS, CDFW, USACE, and/or RWQCB), that includes: details for the restoration activities, a description of how the proposal provides offsets for the temporal loss, success criteria and the timeline for restoration. If habitat is unable to be restored, or the restoration does not meet the success criteria, the impacts would be considered permanent and would require mitigation consistent with the ratios identified in Table 1 below. This mitigation would entail a mitigation plan outlining the enhancement or restoration of habitat within City Owned Preserve Lands or through acquisition of a conservation easement within the Upland Standards Areas or San Diego River Subunit depending on the type of habitat being impacted so that impacts will be mitigated in-kind. The mitigation plan shall include at a minimum: details for the mitigation activities including the target function and services for the native plant communities established, mitigation work plan, performance standards, funding mechanism, and the timeline for completion of the mitigation program. The mitigation site would be included in the Managed Preserve and managed and monitored in perpetuity with funding for long-term management and monitoring provided through a non-wasting endowment.

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Mitigation Ratios for Permanent Unintended Impacts
Vegetation
Type a Habitat Criteria Mitigation Ratio
Riparian
Forest/
Woodland
All riparian forest, including oak
riparian
3:1
Riparian Scrub Drainages with riparian scrub 3:1
Freshwater
Marsh,
Freshwater
Seep, Disturbed
Wetlands,
Natural
Channel, Open
Water e
Absence of native species or small
(<0.25 acre) amount of habitat
2:1 f
Presence of native species or large
(>0.25 acre) amount of habitat
3:1
Vernal Pools b Natural Vernal Pool 4:1
Man-made vernal pools with
indicator plant species
3:1
Man-made pools with covered
wildlife species
3:1
Oak Woodland Oak woodland containing any
Engelmann oaks
3:1
Individual Oaks Trees with at least on trunk of 6” or
more Dbh c or multi-trunked native
oaks with aggregate diameter of 10”
of more.
10:1 by tree
Coastal Sage
Scrub Coastal
Sage/Chaparral
Scrub
Habitat small, isolated patches <1
acres
2:1
Habitat patches >1 acre 3:1
Chaparral All 2:1
Native
Grassland
All 3:1
Non-native
grassland
All 1:1
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Table 1-1. Summary of Project Impacts
Environmental Topic Impact? Mitigation Measures
Level of
Significance
After Mitigation
Disturbed
lands,
Eucalyptus,
agricultural
lands d
No known habitat value for Covered
Species
None
Habitat value for or presence of
burrowing owls
1:1 as appropriate
to ensure like value
Notes:
a Vegetation types based on the Holland Vegetation classification system. See Appendix E, Vegetation Communities Descriptions. All other natural habitat types not listed in this table have a 1:1 mitigation ratio requirement.
b Vernal pool mitigation must meet a ‘no net loss’ criteria through creation of new vernal pool habitat and/or restoration or enhancement of existing vernal pool habitat. Preservation of existing vernal pool alone does not provide mitigation credits. If an existing vernal pool is significantly disturbed, enhancement of the existing pool can be implemented to provide up to a 1:1 mitigation credits towards the total requirement. c Dbh = Diameter at Breast Height. Tree diameter is measured at 4 ½ feet above ground level. This measure is known as diameter at breast height or DBH. Diameter can be measured with diameter tape
d Disturbed land may include agricultural lands, ruderal, eucalyptus, and previously authorized graded areas.
e Any impacts to open water areas within abandoned sand mining pits along the San Diego River should be mitigated with creation of riparian scrub or riparian woodland, as these open water areas are unnatural, are relatively common, and these same areas likely supported riparian areas before mining occurred.
f Different ratios may be required under separate regulatory programs under the Clean Water Act, the Porter-Cologne Water Quality Control Act, and Section 1600 et seq. of the Fish and Game Code.

MM BIO-5 Avoidance of Listed Species Take: Least Bell’s Vireo. All riparian habitat tree trimming or thinning within Zones 1 and 2 and invasive species removal in Zone 3 shall occur outside the least Bell’s vireo breeding season (April 1 through August 153). If that is not possible then no vegetation management activities shall occur during the least Bell’s vireo breeding season until the following requirements have been met:
3 Unitt and Klovstad (2004) states that the nesting season generally lasts from April to July and dates for fledglings ranged between 27 April to 21 August.

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Table 1-1. Summary of Project Impacts
Environmental Topic Impact? Mitigation Measures
Level of
Significance
After Mitigation

1. A qualified biologist shall conduct a focused pre-construction-level survey for least Bell’s vireo using the most recent protocol within all fuel reduction areas containing suitable riparian habitat, including a 500-foot buffer. A minimum of three surveys shall be performed or 3 days prior to Project activities. If presence of least Bell’s vireo is determined or assumed to occur on the Project Site, the following measures shall be required to be implemented:
▪ No vegetation removal shall occur within occupied habitat during the least Bell’s vireo breeding season (April 1 to August 15) or until the nest has shown to be vacated. A 500-foot buffer shall be required around the nest site. If 100% avoidance of occupied habitat is not feasible, consultation with USFWS and California Department of Fish and Wildlife (CDFW shall be initiated prior to implementation of any activities that may impact occupied habitat, directly or indirectly.

All coastal sage scrub thinning shall occur outside the coastal California gnatcatcher breeding season (February 15through August 15). If that is not possible then no vegetation management activities shall occur during the coastal California gnatcatcher breeding season (February 15 through August 15) until the following requirements have been met:

1. A permitted biologist (i.e., possessing a valid Endangered Species Act Section 10(a)(1)(a) Recovery Permit) shall conduct a focused protocol-level survey (i.e., three visit survey) for coastal California gnatcatcher (Polioptila californica californica) using the most recent protocol (USFWS 1997 Coastal California Gnatcatcher Presence/Absence Survey Guidelines) 3 days prior to Project activities within all fuel reduction areas containing coastal sage scrub including a 500-foot buffer. If presence of coastal California gnatcatcher is determined or assumed to occur on the Project EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN JULY 2026
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Table 1-1. Summary of Project Impacts
Environmental Topic Impact? Mitigation Measures
Level of
Significance
After Mitigation
Site, the following measures shall be required to be implemented by the applicant:
a. No vegetation trimming or thinning shall occur within occupied habitat during the coastal California gnatcatcher breeding season (February 15 to August 15). A minimum 500-foot buffer shall be established around occupied nests unless a larger buffer is determined necessary by the permitted biologist based on species behavior, topography, existing disturbance conditions, or other site-specific factors. b. A 500-footThe buffer shall be required around the nest site until it is shown to be vacated. If 100% avoidance of occupied habitat is not feasible, consultation with USFWS and California Department of Fish and Wildlife (CDFW) shall be initiated prior to implementation of any activities that may impact occupied habitat, directly or indirectly.
c. Other measures from FWS-CFWO-16B0293-18F1358; Section 7 Consultation on FEMA Disaster, Mitigation and Preparedness Programs in Imperial, Inyo, Kern, Los Angeles, Orange, Riverside, San Bernardino, and San Diego Counties, California Coastal California Gnatcatcher CAGN-1 through CAGN-4 will apply. CAGN-5 through CAGN-7 do not apply as this project is intended to enhance native habitat and species.

MM BIO-7 Nesting Bird Survey. All nesting bird habitat trimming or thinning shall occur outside the nesting bird breeding season (February 15 through September 30). If the Project requires that work be initiated during the breeding season for nesting birds, in order to avoid direct impacts on active nests, a pre-construction survey shall be conducted in the Project Site and within 500 feet of the Project Site containing suitable nesting resources, by qualified biologists for nesting birds and/or raptors within 3 days prior to Project activities. If the biologist does not find any active nests within or immediately adjacent to the impact areas (i.e., 500 feet), the vegetation clearing work shall be allowed to proceed. If the biologist finds an active nest within or immediately adjacent to the work area and determines that the nest may be impacted or breeding activities substantially disrupted, the biologist shall delineate an appropriate buffer zone. A minimum buffer ranging from 50 EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN JULY 2026
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Table 1-1. Summary of Project Impacts
Environmental Topic Impact? Mitigation Measures
Level of
Significance
After Mitigation
feet for common or disturbance-tolerant species to 500 feet for raptors and special-status species. Larger buffers may be established by the qualified biologist based on species sensitivity, nesting stage, line-of-sight conditions, topography, ambient noise levels, observed behavioral responses, or the nature of the proposed activity. (typically 300 feet for passerines and 500 feet for raptors and special-status species) or appropriate noise mitigation around the nest depending on the sensitivity of the species and the nature of the activity. The nest area and buffer zone shall be avoided until the nest is vacated and the juveniles have fledged or the nest fails. Status of the nest shall be monitored by a qualified biologist. A report shall be submitted to the City of Santee and Wildlife Agencies (i.e., U.S. Fish and Wildlife Service and California Department of Fish and Wildlife) for review prior to discontinuing the noise limits and nest buffers. The nest buffer area shall be demarcated in the field with flagging and stakes or construction fencing. Personnel, including all contractors working on site, are required to be instructed on the sensitivity of the area. No Project activities shall encroach into established buffers without the consent of a monitoring biologist. The buffer shall remain in place until it is determined that the nestlings have fledged and the nest is no longer active. Work can proceed into the buffer when the qualified biologist has determined that the nest is no longer active or if appropriate noise mitigation is in place.

MM BIO-8 Avoidance of Listed Species Take: Crotch’s Bumblebee. A preconstruction survey shall be conducted by a qualified biologist with expertise in surveying for bumble bees no more than 5 days prior to any project activities occurring within Zones 1, 2, or 3. If a Crotch’s bumble bee nest is detected during the pre-construction survey, the Project’s biological monitor shall establish, monitor, and maintain a no-work buffer around the nest. The size and configuration of the no-work buffer shall be based on best professional judgment of the Project biologist in consultation with the Wildlife Agencies. The buffer shall provide at least 50 feet of clearance around nest entrances.

Project activities shall not occur within the no-work buffer until the colony is no longer active. To determine that a nest is no longer active, the nest shall be observed for a minimum of 60 minutes each day across a minimum of 3 days EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN JULY 2026
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Environmental Topic Impact? Mitigation Measures
Level of
Significance
After Mitigation
during suitable flight weather (i.e., ambient air temperature between 60° and 90° degrees F, winds under 10 mph, and no precipitation higher than a drizzling rain). If no bees are seen flying in or out of the nest by the end of the observation period, it shall be determined that the nest is no longer active. If Project activities occur outside of the colony active period (April 1–August 31), then pre-construction surveys for active bee nest colonies are not required.

If Crotch’s bumble bee is observed during the pre-construction survey, the Project’s biological monitor shall ensure the individual(s) are not impacted by Project activities through establishment of a no-work area. The biological monitor shall also review the immediate vicinity to ensure no nests are present.

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 Game or U.S. Fish and
Wildlife Service?
Potentially
significant
impact
MM BIO-3
MM BIO-4
MM BIO-9 Tree Survey. Prior to the commencement of vegetation management activities within Zones 1 to 3, a Certified Arborist shall be present to conduct a comprehensive tree inventory to determine the exact locations for dead, dying, and invasive species slated for removal. The comprehensive tree inventory may also occur concurrently with vegetation management activities so as not to interfere with Project timing. Trees shall be marked or flagged by the Certified Arborist for the contractor and the tree inventory and removal tracking shall be provided to the City of Santee.

Less-thansignificant impact
with mitigation
incorporated
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?
Potentially
significant
impact
MM BIO-2
MM BIO-3
MM BIO-10 Jurisdictional Aquatic Resources Permitting. The City of Santee shall obtain the applicable permits, for treatment activities (i.e., trimming or thinning of native or non-native vegetation within Zones 1 and 2) occurring within jurisdictional aquatic resources, such as a Section 404 permit from USACE, a Streambed Alteration Agreement from CDFW, and a 401 Water Quality Certification/Waste Discharge Requirement from the RWQCB. No native or nonnative vegetation trimming or thinning in Zones 1 and 2 shall occur within any jurisdictional riparian/wetland vegetation communities on the Project Site prior to issuance of aquatic resources permits.

Less-thansignificant impact
with mitigation
incorporated
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Table 1-1. Summary of Project Impacts
Environmental Topic Impact? Mitigation Measures
Level of
Significance
After Mitigation
MM BIO-11 Jurisdictional Aquatic Resources Avoidance. Vegetation management activities occurring within Zone 3 shall only involve treatment or removal of dead, dying, or invasive species. The Project shall commit to avoid impacting streams within Zones 1, 2, and 3 by crossing them using temporary rubber mats or pads to distribute weight and minimize vegetation trampling and soil disturbance, and helicopter and/or crane removal where equipment access is constrained and hand carry is infeasible.

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?
Less-thansignificant
impact
N/A Less-thansignificant impact
Would the Project conflict with
any local policies or ordinances
protecting biological resources,
such as a tree preservation
policy or ordinance?
Less-thansignificant
impact
N/A Less-thansignificant impact
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?
Less-thansignificant
impact
N/A Less-thansignificant impact
Would the Project have a
cumulative effect on Biological
Resources?
Potentially
significant
impact
MM BIO-1 through MM BIO-10 Less-thansignificant impact with mitigation
incorporated
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Table 1-1. Summary of Project Impacts
Environmental Topic Impact? Mitigation Measures
Level of
Significance
After Mitigation
Cultural, Tribal Cultural
Would the Project cause a
substantial adverse change in
the significance of a historical
resource as defined in CEQA
Guidelines Section 15064.5?
Less-thansignificant
impact
N/A Less-thansignificant impact
Would the Project cause a
substantial adverse change in
the significance of an
archaeological resource
pursuant to CEQA Guidelines
Section 15064.5?
Potentially
significant
impact
MM CUL-1 Resource Avoidance. Measures shall be taken to prevent inadvertent disturbance of archaeological resource sites CA-SDI-005050, CA-SDI-010148, SDRFM-DF-S-002, and SDFRM-DF-S-003. Prior to the commencement of any ground-disturbing activities within 100 feet of the resource boundaries of CA-SDI005050, CA-SDI-010148, SDRFM-DF-S-002, and SDRFM-DF-S-003, temporary work buffers shall be placed to protect the sites from inadvertent disturbances associated with Project implementation. Following Project implementation within the vicinity of CA-SDI-005050, CA-SDI-010148, SDRFM-DF-S-002, and SDRFMDF-S-003, the temporary work buffers shall be removed. Temporary work buffers may include exclusionary fencing, flagging, and/or Environmentally Sensitive Area (ESA) signage. An archaeological monitor shall guide the placement and erection of the temporary work buffers to ensure archaeological sites CA-SDI005050, CA-SDI-010148, SDRFM-DF-S-002, and SDRFM-DF-S-003 are properly protected.

Temporary work buffers shall remain in place for the duration of Project activities occurring in the vicinity of the resource. Following completion of work within each protected area, buffers shall be removed. The archaeological monitor shall confirm that removal occurs only after all potential disturbance risks have ended.

Under no circumstances shall Project personnel, equipment, or materials enter the established buffer zones. If construction staff, monitors, or City representatives observe potential encroachment or damage, ground‑disturbing activities shall be immediately redirected or halted until appropriate corrective action is taken.

MM CUL-2 Cultural Resources Monitoring. To mitigate for potential impacts to previously unknown, buried cultural resources within the Project APE and to Less-thansignificant impact
with mitigation
incorporated
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Table 1-1. Summary of Project Impacts
Environmental Topic Impact? Mitigation Measures
Level of
Significance
After Mitigation
prevent impacts to known archaeological resources, an archaeological monitoring program shall be implemented pursuant to the City of Santee (City) regulations, the California Environmental Quality Act (CEQA), and Section 106 of the National Historic Preservation Act and shall include the following requirements:

Pre-Construction
a. The applicant shall contract a Secretary of Interior qualified Lead Archaeologist to oversee the cultural monitoring program. The Lead Archaeologist shall contract with a Kumeyaay monitor to conduct Native American monitoring for the Project. The Lead Archaeologist and Kumeyaay Native American monitor(s) shall attend the pre-construction meeting to explain the monitoring requirements.

Construction
a. Monitoring. Both the archaeological and Kumeyaay Native American monitor(s) are to be on site during initial ground-disturbing activities. b. The frequency and location of monitoring of native soils will be determined by the Lead Archaeologist in consultation with the Kumeyaay Native American monitor(s).
c. If cultural resources are identified:
a. Both the archaeological and Kumeyaay Native American monitor(s) have the authority to divert or temporarily halt ground disturbance operations in the area of the discovery.
b. The archaeological monitor shall contact the Lead Archaeologist. c. The Lead Archaeologist shall contact the City.
d. The Lead Archaeologist in consultation with the City and Kumeyaay Native American monitor(s) shall determine the significance of discovered resources. Construction activities will be allowed to resume after the City has concurred with the significance evaluation.
a. Isolates and non-significant deposits shall be minimally documented in the field. Should the isolates and non-significant deposits not be collected by the archaeological monitor, the 1 – EXECUTIVE SUMMARY
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Table 1-1. Summary of Project Impacts
Environmental Topic Impact? Mitigation Measures
Level of
Significance
After Mitigation
Kumeyaay Native American monitor(s) may collect the cultural material for transfer to a Tribal curation facility or repatriation program.
b. If cultural resources are determined to be potentially significant, avoidance measures shall be developed by the Lead Archaeologist in consultation with the Kumeyaay Native American monitor(s) and approved by the City. If avoidance is not feasible, a research design and data recovery plan shall be prepared by the Lead Archaeologist in consultation with the Kumeyaay Native American monitor(s) and approved by the City. The preferred option is avoidance.
c. If human remains are identified
d. Upon the identification of possible human remains, no further disturbance shall occur in the area of the find until procedures stipulated in Public Resources Code Section 5097.98, CEQA Section 15064.5 and Health and Safety Code Section 7050.5 are completed.
e. Upon completion of Project ground disturbance, a final report shall be prepared substantiating that earth-disturbing activities are completed and whether cultural resources were encountered. A copy of the final report shall be submitted to the South Coastal Information Center and any culturally affiliated tribe who requests a copy.

Would the Project disturb any
human remains, including
those interred outside of
dedicated cemeteries?
Potentially
significant
impact
MM CUL-3 Inadvertent Discovery. In order to mitigate impacts to human remains to a level that is less than significant, procedures for proper treatment of unanticipated discoveries must comply with the California Environmental Quality Act (CEQA) Guidelines. In the event of discovery of unanticipated human remains, personnel shall comply with Public Resources Code Section 5097.98, CEQA Section 15064.5, and Health and Safety Code Section 7050.5 during earth-disturbing activities:

If any human remains are discovered, the construction personnel or the appropriate representative shall contact the County Coroner and the City. Upon identification of human remains, no further disturbance shall occur in the area of Less-thansignificant impact
with mitigation
incorporated
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Table 1-1. Summary of Project Impacts
Environmental Topic Impact? Mitigation Measures
Level of
Significance
After Mitigation
the find until the County Coroner has made the necessary findings as to origin. If the remains are determined to be of Native American origin, the Most Likely Descendant, as identified by the Native American Heritage Commission, shall be contacted by the property owner or their representative in order to determine proper treatment and disposition of the remains. The immediate vicinity where the Native American human remains are located is not to be damaged or disturbed by further development activity until consultation with the Most Likely Descendant regarding their recommendations as required by California Public Resources Code Section 5097.98 has been conducted. California Public Resources Code Section 5097.98, CEQA Section 15064.5 and Health and Safety Code Section 7050.5 shall be followed.

Would the Project cause a
substantial adverse change in
the significance of a tribal
cultural resource, defined in
Public Resources Code Section
21074 as either a site, feature,
place, cultural landscape that is
geographically defined in terms
of the size and scope of the
landscape, sacred place, or
object with cultural value to a
California Native American
tribe, and that is listed or
eligible for listing in the
California Register of Historical
Resources, or in a local register
of historical resources as
defined in Public Resources
Code Section 5020.1(k)?
Potentially
significant
impact
MM CUL-1
MM CUL-2
Less-thansignificant impact
with mitigation
incorporated
Would the Project cause a
substantial adverse change in
the significance of a tribal
Potentially
significant
impact
MM CUL-1
MM CUL-2
Less-thansignificant impact
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Table 1-1. Summary of Project Impacts
Environmental Topic Impact? Mitigation Measures
Level of
Significance
After Mitigation
cultural resource, defined in
Public Resources Code Section
21074 as either a site, feature,
place, cultural landscape that
is geographically defined in
terms of the size and scope of
the landscape, sacred place, or
object with cultural value to a
California Native American
tribe, and that is a resource
determined by the lead agency,
in its discretion and supported
by substantial evidence, to be
significant pursuant to criteria
set forth in subdivision (c) of
Public Resources Code Section
5024.1? In applying the
criteria set forth in subdivision
(c) of Public Resource Code
Section 5024.1, the lead
agency shall consider the
significance of the resource to
a California Native American
tribe.
with mitigation
incorporated
Would the Project have a
cumulative effect on Cultural,
Tribal Cultural, and
Paleontological Resources?
Potentially
significant
impact
MM CUL-1 through MM CUL-3 Less-thansignificant impact
with mitigation
incorporated
Hazards and Hazardous Materials
Would the Project create a
significant hazard to the public
or the environment through the
routine transport, use, or
Less-thansignificant
impact
N/A Less-thansignificant impact
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Table 1-1. Summary of Project Impacts
Environmental Topic Impact? Mitigation Measures
Level of
Significance
After Mitigation
disposal of hazardous
materials?
Would the Project create a
significant hazard to the public
or the environment through
reasonably foreseeable upset
and accident conditions
involving the release of
hazardous materials into the
environment?
Less-thansignificant
impact
N/A Less-thansignificant impact
Would the Project emit
hazardous emissions or handle
hazardous or acutely hazardous
materials, substances, or waste
within one-quarter mile of an
existing or proposed school?
Less-thansignificant
impact
N/A Less-thansignificant impact
Would the Project be located on
a site which is included on a list
of hazardous materials sites
compiled pursuant to
Government Code Section
65962.5 and, as a result, would
create a significant hazard to
the public or the environment?
Less-thansignificant
impact
N/A Less-thansignificant impact
Would the Project be located
within an airport land use plan,
be within two miles of a public
airport, and result in a safety
hazard or excessive noise for
people residing or working in
the Project area?
Less-thansignificant
impact
N/A Less-thansignificant impact
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Table 1-1. Summary of Project Impacts
Environmental Topic Impact? Mitigation Measures
Level of
Significance
After Mitigation
Would the Project impair
implementation of or physically
interfere with an adopted
emergency response plan or
emergency evacuation plan?
Less-thansignificant
impact
N/A Less-thansignificant impact
Would the Project expose
people or structures, either
directly or indirectly, to a
significant risk of loss, injury, or
death involving wildland fires?
Less-thansignificant
impact
N/A Less-thansignificant impact
Would the Project have a
cumulative effect on Hazards
and Hazardous Materials?
Less-thansignificant
impact
N/A Less-thansignificant impact
Hydrology and Water Quality
Would the Project violate any
water quality standards or
waste discharge requirements
or otherwise substantially
degrade surface or groundwater
quality?
Less-thansignificant
impact
N/A Less-thansignificant impact
Would the Project substantially
decrease groundwater supplies
or interfere substantially with
groundwater recharge such that
the Project may impede
sustainable groundwater
management of the basin?
Less-thansignificant
impact
N/A Less-thansignificant impact
Would the Project substantially
alter the existing drainage
pattern of the site or area,
including through the alteration
of the course of a stream or
Less-thansignificant
impact
N/A Less-thansignificant impact
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Table 1-1. Summary of Project Impacts
Environmental Topic Impact? Mitigation Measures
Level of
Significance
After Mitigation
river or through the addition of
impervious surfaces, in a
manner which would:
i) result in substantial erosion
or siltation on or off-site;
ii) substantially increase the
rate or amount of surface
runoff in a manner which
would result in flooding on
or off site;
iii)create or contribute runoff
water which would exceed
the capacity of existing or
planned stormwater
drainage systems or
provide substantial
additional sources of
polluted runoff; or
iv)impede or redirect flood
flows?
Would the Project in flood
hazard, tsunami, or seiche
zones, risk release of pollutants
due to project inundation?
Less-thansignificant
impact
N/A Less-thansignificant impact
Would the Project conflict with
or obstruct implementation of a
water quality control plan or
sustainable groundwater
management plan?
Less-thansignificant
impact
N/A Less-thansignificant impact
Would the Project have a
cumulative effect on Hydrology
and Water Quality?
Less-thansignificant
impact
N/A Less-thansignificant impact
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Table 1-1. Summary of Project Impacts
Environmental Topic Impact? Mitigation Measures
Level of
Significance
After Mitigation
Noise
Would the Project result in
generation of a substantial
temporary or permanent
increase in ambient noise levels
in the vicinity of the Project in
excess of standards
established in the local general
plan or noise ordinance, or
applicable standards of other
agencies?
Potentially
significant
impact
MM NOI-1 Noise Reduction Techniques: Should mobile or stationary heavy construction equipment (i.e., self-propelled or electrically, mechanically, or hydraulically powered) associated with Project implementation operate at horizontal distances closer than 45 feet horizontal to an off-site noise-sensitive receiver position (e.g., exterior of an existing residence), the Project contractor(s) shall apply either of the following options as noise reduction techniques to keep noise exposures at or below the FTA guidance-based threshold (80 dBA 8-hour Leq during daytime hours):
a. Administrative noise control – reduce heavy equipment operation time to just 1 hour per 8-hour period; or
b. Temporary noise abatement – install 8-foot-tall (minimum height) plywood sheet barriers (or acoustical blankets suspended on chain-link fencing or other support means) along or parallel with an extent of the Project boundary that adjoins the receiving noise-sensitive property. The barrier extent shall have, end to end, a length of no less than the sum of the width of the property to be protected plus four times the perpendicular distance between it and the receiver position, where this perpendicular is extended from (or through) the midpoint of the receiving property line. Prior to the installation and use of temporary noise abatement, a qualified biologist shall confirm and verify with the City that the placement of the barriers are not located within any environmentally sensitive areas (e.g., special-status plant locations, sensitive vegetation communities, or jurisdictional aquatic resources) and would not impact any wildlife species or their movement.

Less-thansignificant impact
with mitigation
incorporated
Would the Project result in
generation of excessive
groundborne vibration or
groundborne noise levels?
Less-thansignificant
impact
N/A Less-thansignificant impact
For a project located within the
vicinity of a private airstrip or an
airport land use plan or, where
such a plan has not been
Less-thansignificant
impact
N/A Less-thansignificant impact
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Table 1-1. Summary of Project Impacts
Environmental Topic Impact? Mitigation Measures
Level of
Significance
After Mitigation
adopted, within two miles of a
public airport or public use
airport, would the Project
expose people residing or
working in the Project area to
excessive noise levels.

Would the Project have a
cumulative effect on Noise?
Potentially
significant
impact
MM NOI-1 Less-thansignificant impact
with mitigation
incorporated
Wildfire
Would the Project impair
implementation of or physically
interfere with an adopted
emergency response plan or
emergency evacuation plan?
Less-thansignificant
impact
N/A Less-thansignificant impact
Due to slope, prevailing winds,
and other factors, would the
Project exacerbate wildfire risks,
and thereby expose Project
occupants to pollutant
concentrations from a wildfire or
the uncontrolled spread of a
wildfire?
Less-thansignificant
impact
N/A Less-thansignificant impact
Would the Project require the
installation or maintenance of
associated infrastructure (such
as roads, fuel breaks,
emergency water sources,
power lines, or other utilities)
that may exacerbate fire risk or
that may result in temporary or
Less-thansignificant
impact
N/A Less-thansignificant impact
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Table 1-1. Summary of Project Impacts
Environmental Topic Impact? Mitigation Measures
Level of
Significance
After Mitigation
ongoing impacts to the
environment?
Would the Project expose
people or structures to
significant risks, including
downslope or downstream
flooding or landslides, as a
result of runoff, post-fire slope
instability, or drainage
changes?
Less-thansignificant
impact
N/A Less-thansignificant impact
Would the Project have a
cumulative effect on Wildfire?
Less-thansignificant
impact
N/A Less-thansignificant impact
Notes: MSCP = Multiple Species Conservation Plan; USACE = U.S. Army Corps of Engineers; RWQCB = Regional Water Quality Control Board; APE = area of potential effects; FTA = Federal Transit Administration; dBA = A-weighted decibel.

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Significant and Unavoidable Impacts
As identified in Table 1-1, the Project would not result in significant and unavoidable impacts.

1.9 Alternatives to the Project
Section 15126.6(a) of the CEQA Guidelines states that an EIR shall describe “a range of reasonable alternatives to the project, or to the location of the project, which would feasibly attain most of the basic objectives of the project but would avoid or substantially lessen any of the significant effects of the project,” as well as provide an evaluation of “the comparative merits of the alternatives.” Under CEQA Guidelines Section 15126.6(a), an EIR does not need to consider alternatives that are not feasible, nor does it need to address every conceivable alternative to the Project. The range of alternatives “is governed by the ‘rule of reason’ that requires the EIR to set forth only those alternatives necessary to permit a reasoned choice” (14 CCR 15126.6[f]).

No Project Alternative (Alternative 1)
Under Alternative 1, vegetation management within the Project Site would not occur, and the existing environment would remain in its current state. The Project Site would remain unchanged, and non-native vegetation would remain in the San Diego River corridor and thinning closer to existing structures would not occur. In the short term, consistent with the existing conditions, the Project Site would continue to experience frequent ignitions. Under Alternative 1, it is assumed any existing maintenance and recreational activity at the Project Site would remain unchanged from existing conditions.

Zone 3 Standards Alternative (Alternative 2)
Under Alternative 2, the Project Site would include treatment or removal of non-native species, dead or dying vegetation, and debris, consistent with the standard of Zone 3 across the entire Project Site. The Project Site would not include any thinning, mowing, or pruning activities described in Zone 1 or Zone 2 standards. This alternative would have the same boundary and treatment area as the Project.

Manual and Mechanical Treatment (Alternative 3)
Under Alternative 3, the Project would only use manual and mechanical treatment methods to implement the standards for Zones 1-3. This Alternative would not include any chemical or prescribed herbivory treatments. This alternative would have the same boundary and treatment area as the Project.

1.10 Areas of Controversy/Issues to Be Resolved
The scope of this EIR includes the potential environmental impacts identified in the Notice of Preparation that was available for public review from February 6, 2026, through March 6, 2026, and was extended at the state level through March 11, 2026, to accommodate a CEQAnet delay. Comments received during a public scoping held on February 18, 2026, at City Hall in Santee; and agency and public written comments received in response to the Notice of Preparation.

A summary of these written comment letters is provided in Table 1-2. The written comments and the Notice of Preparation are included as Appendix A of this EIR.

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Table 1-2. Summary of Notice of Preparation Comments
Commenter Date Summary of Environmental Issues Raised
EIR Chapter/Section Where
Comment is Addressed
State Agency
Native
American
Heritage
Commission
(NAHC)
2/13/26 ▪ Cultural Resources
▪ Tribal Cultural Resources and Tribal
Consultation
▪ Inadvertent discovery of archaeological
resources and Native American human
remains
▪ Section 4.2,
▪ Cultural and Tribal Cultural
Resources
San Diego
County
Archaeological
Society
2/17/26 ▪ Cultural Resources
▪ Tribal Cultural Resources
▪ Access to cultural sites that were
previously inaccessible
▪ Section 4.2, Cultural and
Tribal Cultural Resources
County of San
Diego Public
Works
3/3/26 ▪ Vegetation removal to overlap with
County-maintained right-of-way (ROW)
▪ Chapter 3, Project
Description
Caltrans 3/9/26 ▪ Transportation right-of-way (ROW) ▪ Chapter 3, Project Description
California
Department of
Fish and
Wildlife (CDFW)
3/11/26 ▪ Biological Resources, Impacts to SpecialStatus plant and wildlife species; riparian, aquatic, and streambed resources;
sensitive natural communities
▪ Section 4.1, Biological
Resources
Private Organizations and Members of the Public
Sara Kniffen 2/10/26 No specific environmental issues raised Not Applicable Randy
Northcote
2/12/26 ▪ Vegetation removal of dead brush and
non-native vegetation
▪ Chapter 3, Project
Description
▪ Section 4.6, Wildfire
Amy Newton 2/23/26 ▪ Brush Management and wildfire risk adjacent to homes
▪ Section 4.3, Hazards and
Hazardous Materials
▪ Section 4.6, Wildfire
Kelly
Debenham
3/24/26 ▪ Impacts to wildlife and vegetation (hawks,
migratory birds, rabbits, skunks, possum,
coyotes, mule deer)
▪ Changes to vegetation landscape that
would result in changes to the hydrology of
the area
▪ Section 4.1, Biological
Resources
▪ Section 4.4, Hydrology and
Water Quality
Issues to be Resolved by Lead Agency
Section 15123(b)(3) of the CEQA Guidelines requires that an EIR contain a discussion of issues to be resolved. With respect to the proposed Project, the key issues to be resolved include decisions by the City, as lead agency, as to the following:
▪ Whether this environmental document adequately describes the environmental impacts of the Project. ▪ Whether the recommended mitigation measures should be modified and/or adopted. ▪ Whether there are other mitigation measures or alternatives that should be considered for the Project besides those identified in the Draft EIR.

EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 2-1
2 Introduction

2.1 Purpose of the California Environmental Quality
Act Process
This Environmental Impact Report (EIR) has been prepared in accordance with the California Environmental Quality Act (CEQA) to evaluate the potential environmental effects associated with implementation of the San Diego River Fire Hazard Mitigation Program: Fuels Treatment Plan Project (Project). Consistent with CEQA Guidelines Section 15161, this document is a project-level EIR. As the lead agency for the Project, the City of Santee (City) must complete an environmental review to determine if the Project could potentially result in significant adverse environmental effects. A detailed description of the Project is provided in Chapter 3, Project Description.

CEQA Guidelines Section 15002 states that the basic purposes of CEQA are the following:
▪ Inform governmental decision makers and the public about the potential significant environmental effects of proposed activities
▪ Identify the ways that environmental damage can be avoided or significantly reduced. ▪ Prevent significant, avoidable damage to the environment by requiring changes in projects through the use of alternatives or mitigation measures when the governmental agency finds the changes to be feasible.

If a project will be approved involving significant environmental effects, the lead agency must also disclose to the public the reasons why a governmental agency approved the project in the manner the agency chose.

This EIR provides project-level analysis of the potential environmental effects related to implementation of the Project. The level of impact analysis in this EIR corresponds to the degree of specificity deemed appropriate in accordance with CEQA Guidelines Section 15146. This EIR addresses the potentially significant environmental impacts that could occur as a result of implementation of the Project. This document also identifies appropriate and feasible mitigation measures, where necessary, and includes Project alternatives that could be adopted to reduce or avoid potential significant environmental effects.

2.2 Legal Authority and Lead Agency
This EIR has been prepared in accordance with all criteria, standards, and procedures of CEQA (PRC Section 21000 et seq.), the CEQA Guidelines (14 CCR 15000 et seq.), and the rules, regulations, and procedures for implementing CEQA as adopted by the City.

Pursuant to CEQA Section 21067 and CEQA Guidelines Article 4 and Section 15367, the City is the lead agency under whose authority this EIR has been prepared. “Lead agency” refers to the public agency that has the principal responsibility for carrying out or approving a project. Serving as the lead agency and before taking action to approve the Project, the City has the obligation to (1) ensure that this EIR was completed in accordance with CEQA; (2) review and consider the information contained in this EIR as part of its decision-making process; (3) make a statement that this EIR reflects the City’s independent judgment; (4) ensure that all significant impacts on the environment are eliminated or substantially lessened, where feasible; and, if necessary (5) make written findings for each unavoidable significant environmental effect stating the reasons why mitigation measures or Project alternatives 2 – INTRODUCTION
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 2-2
identified in this EIR are infeasible and citing the specific benefits of the Project that outweigh its unavoidable adverse effects (14 CCR 15090–15093).

Pursuant to CEQA Guidelines Sections 15040 through 15043, and upon completion of the CEQA review process, the City will have the legal authority to do any of the following:
▪ Approve the Project
▪ Require feasible changes in any or all activities involved in the Project to substantially lessen or avoid significant effects on the environment
▪ Disapprove the Project, if necessary, to avoid one or more significant effects on the environment that would occur if the Project was approved as proposed
▪ Approve the Project, even though the Project would cause a significant effect on the environment if the City makes a fully informed and publicly disclosed decision that (1) there is no feasible way to lessen the effect or avoid the significant effect, and (2) expected benefits from the Project will outweigh significant environmental impacts of the Project
This EIR is an informational document intended for use by City decision makers, trustee, and responsible agencies, and members of the general public in evaluating the physical environmental impacts of the Project. This EIR is the primary reference document for the formulation and implementation of a mitigation monitoring and reporting program for the Project, in compliance with Public Resources Code (PRC) Section 21081.6. Environmental impacts cannot always be mitigated to a level considered less than significant. In accordance with Section 15093(b) of the CEQA Guidelines, if a lead agency approves a project that has significant impacts that are not substantially mitigated (i.e., significant unavoidable impacts), the agency shall state in writing the specific reasons for approving the Project, based on the final CEQA documents and any other information in the public record. This is defined in Section 15093 of the CEQA Guidelines as “a statement of overriding considerations.”

2.3 Responsible and Trustee Agencies
PRC Section 21104 requires that all EIRs be reviewed by state responsible and trustee agencies (see also 14 CCR 15082 and 15086[a]). As defined by CEQA Guidelines Section 15381, “the term ‘Responsible Agency’ includes all public agencies other than the Lead Agency which have discretionary approval power over the project.” A trustee agency is defined in CEQA Guidelines Section 15386 as “a state 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 this Project, the following agencies have discretionary approval power over the Project and are considered responsible agencies:
▪ U.S. Army Corps of Engineers
▪ Federal Emergency Management Agency
▪ U.S. Fish and Wildlife Service
▪ California Department of Fish and Wildlife
▪ Regional Water Quality Control Board
▪ State Historic Preservation Office
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For this Project, the following agency is considered a trustee agency:
▪ California Department of Fish and Wildlife

2.4 Summary of Project Analyzed in this Environmental
Impact Report
The Project includes the implementation of the San Diego River Fire Hazard Mitigation Program: Fuels Treatment Plan, which proposes fuel treatment and vegetation management within the segment of the San Diego River within the City of Santee. The Fuels Treatment Plan provides a framework for vegetation management across the approximately 300-acre Project Site and includes treatment strategies tailored to the site’s wildfire exposure, access conditions, existing vegetation, and proximity to sensitive resources. The plan is designed to protect communities, critical infrastructure, and sensitive resources by reducing wildfire risk through coordinated vegetation management across the Project Site. It emphasizes selective vegetation modification techniques that support defensible space and risk reduction while preserving ecological function, minimizing soil disturbance, and protecting sensitive resources. A complete Project Description and permits and approvals required for Project implementation are provided in Chapter 3, Project Description, and described in Chapter 4, Environmental Analysis, of this Draft EIR.

2.5 Scope of Environmental Analysis

2.5.1 Notice of Preparation Scoping Process
The purpose of this EIR is to evaluate the potential environmental impacts associated with implementation of the Project. The City concluded that the Project could potentially have direct or indirect adverse effects on the environment. Accordingly, the City determined the need for preparation of an EIR for the Project. Potentially significant impacts were identified based on review of comments received in response to the Notice of Preparation (NOP) that was available for public review from February 6, 2026, through Wednesday, March 6, 20261 (see Appendix A) and additional research and analysis of relevant Project data during preparation of this Draft EIR. A scoping meeting for this Project was held on February 18, 2026, at the Santee City Hall Council Chambers (10602 Magnolia Avenue, Santee, California 92701).

A summary of written comment letters received is provided in Table 2-1. Nine written comments were received during the NOP period.
1 Due to a delay in the uploading of the NOP to CEQA Net, the NOP Scoping period was extended for State agencies through March 11, 2026.
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Table 2-1. Summary of Notice of Preparation Comments
Commenter Date
Summary of Environmental Issues
Raised
EIR Chapter/Section
Where Comment is
Addressed
Private Organizations and Members of the Public
Sara Kniffen February 10, 2026 No specific environmental issues raised Not Applicable Randy Northcote February 12, 2026 ▪ Vegetation removal of dead brush and non-native vegetation
▪ Chapter 3, Project
Description
▪ Section 4.6, Wildfire
Native American
Heritage
Commission
February 13, 2026 ▪ Cultural Resources
▪ Tribal Cultural Resources and Tribal
Consultation
▪ Inadvertent discovery of
archaeological resources and Native
American human remains
▪ Section 4.2, Cultural
and Tribal Cultural
Resources
San Diego
County
Archaeological
Society
February 17, 2026 ▪ Cultural Resources
▪ Tribal Cultural Resources
▪ Access to cultural sites that were
previously inaccessible
▪ Section 4.2, Cultural
and Tribal Cultural
Resources
Amy Newton February 23, 2026 ▪ Brush Management and wildfire risk adjacent to homes
▪ Section 4.3,
Hazards and
Hazardous
Materials
▪ Section 4.6, Wildfire
County of San
Diego Public
Works
March 3, 2026 ▪ Vegetation removal to overlap with
County maintained right-of-way (ROW)
▪ Chapter 3, Project
Description
Kelly Debenham March 4, 2026 ▪ Impacts to wildlife and vegetation (hawks, migratory birds, rabbits,
skunks, possum, coyotes, mule deer)
▪ Changes to vegetation landscape that
would result in changes to the
hydrology of the area
▪ Section 4.1,
Biological
Resources
▪ Section 4.4,
Hydrology and
Water Quality
Caltrans March 9,2026 ▪ Transportation right-of-way (ROW) ▪ Chapter 3, Project Description
California
Department of
Fish and Wildlife
March 11, 2026 ▪ Lake and Streambed Alteration
▪ Impacts to listed species
▪ Compliance with current land
protections
▪ Alternatives
▪ Biological baseline
▪ Direct and indirect impacts
▪ Cumulative impacts
▪ Nesting Birds
▪ Section 4.1,
Biological
Resources
▪ Chapter 7,
Alternatives
Note: EIR = Environmental Impact Report.
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2.5.2 Environmental Effects Found Not to Be Significant Pursuant to CEQA, the discussion of potential environmental impacts is focused on those impacts that could be significant or potentially significant. CEQA allows the lead agency to limit the detail of discussion of the environmental impacts that are not considered potentially significant (PRC Section 21100; 14 CCR 15126.2[a] and 15128). CEQA requires that the discussion of any significant environmental effect be limited to substantial, or potentially substantial, adverse changes in physical conditions that exist within the affected area, as defined in PRC Section 21060.5. In accordance with CEQA Guidelines Section 15143, environmental impacts dismissed in an analysis as clearly insignificant and unlikely to occur need not be discussed further in the EIR unless the lead agency subsequently receives information inconsistent with the finding.

Based on a review of comments received in response to the NOP (Appendix A) as well as additional research and analysis of relevant Project data during preparation of this Draft EIR, it was determined, for reasons described in Chapter 5, Effects Found Not to Be Significant, of this EIR, that the Project would not result in significant environmental impacts in the following resource areas. Thus, with the exception of the impact discussion in Chapter 5 of this EIR, these environmental resource areas are not discussed at further length in this EIR:
▪ Aesthetics
▪ Agricultural and Forestry Resources
▪ Air Quality
▪ Energy
▪ Geology and Soils
▪ Greenhouse Gas Emissions
▪ Land Use and Planning
▪ Mineral Resources
▪ Population and Housing
▪ Public Services
▪ Recreation
▪ Transportation
▪ Utilities and Service Systems

2.5.3 Environmental Issues Determined to be
Potentially Significant
Pursuant to CEQA and CEQA Guidelines Section 15064, the discussion of potentially significant environmental impacts is focused in this EIR on those impacts that the lead agency has determined could be potentially significant.

A determination of the environmental impacts that would be potentially significant was made for the Project based on a review of comments received as part of the NOP scoping process and additional research and analysis of relevant information during preparation of this EIR. The following environmental issue areas were determined to potentially result in significant impacts and are addressed at further length in this EIR:
▪ Biological Resources
▪ Cultural and Tribal Cultural Resources
▪ Hazards and Hazardous Materials
▪ Hydrology and Water Quality
▪ Noise
▪ Wildfire

2.6 Organization of this Environmental Impact Report
This EIR contains all of the information required to be included in an EIR, as specified by the CEQA Statutes and Guidelines (PRC Section 21000 et seq.; 14 CCR 15000 et seq.). CEQA requires that an EIR contain, at a 2 – INTRODUCTION
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 2-6
minimum, specified content. The following provides a quick reference to locate the CEQA-required sections within this document:
▪ Chapter 1: Executive Summary. The Executive Summary provides a summary of the Project, Project alternatives, Project impacts, cumulative impacts, recommended mitigation measures, and the level of significance after mitigation for each environmental issue. ▪ Chapter 2: Introduction. The Introduction provides an overview of the Project and the CEQA process, and describes the purpose, scope, and components of this EIR. ▪ Chapter 3: Project Description. The Project Description provides a detailed description of the Project, including the location and Project characteristics. The intended uses of this EIR, Project background, Project objectives, and required Project approvals are also addressed. ▪ Chapter 4: Environmental Analysis. The Environmental Analysis chapter analyzes the environmental impacts of the Project. Impacts are organized into major environmental topic areas. Each topic area includes a description of the environmental setting, regulatory setting, significance criteria, mitigation measures, and level of significance after mitigation. The following specific environmental areas are addressed in Chapter 4:
- Section 4.1 – Biological Resources
- Section 4.2 – Cultural and Tribal Cultural Resources
- Section 4.3 – Hazards and Hazardous Materials
- Section 4.4 – Hydrology and Water Quality
- Section 4.5 -- Noise
- Section 4.6 – Wildfire
▪ Chapter 5: Effects Found Not to Be Significant. The Effects Found Not to Be Significant chapter provides a summary of environmental topics that have been determined, based on review of comments received in response to the NOP and additional research and analysis of relevant Project data during preparation of this Draft EIR, to result in less-than-significant or no impact, and therefore, further discussion is not warranted. A brief discussion of these environmental topics are provided in this chapter. ▪ Chapter 6: Other CEQA Considerations. The Other CEQA Considerations chapter provides a discussion of cumulative impacts and other environmental impacts, including unavoidable, irreversible, and growthinducing impacts. ▪ Chapter 7: Alternatives. The Alternatives chapter provides a comparison between the Project impacts and three Project alternatives: (1) the No Project, (2) Non-native Removal Only Alternative, and (3) the Manual and Mechanical Treatment only Alternative.
▪ Chapter 8: List of Preparers. The List of Preparers chapter provides a list of the organizations, persons consulted, and various individuals who contributed to the preparation of this EIR. This section also includes a list of the lead agency personnel and technical consultants used to prepare this EIR. ▪ Appendices. The technical appendices contain the NOP and written comments received in response to the NOP and technical studies prepared to support the analyses and conclusions in this EIR. - Appendix A, Notice of Preparation and Scoping Comments - Appendix B, Biological Resources Letter Report
- Appendix C, Recommended Cultural Area of Potential Effects for the San Diego River Fire Hazard Mitigation Plan Phase I
- Appendix D, Cultural Resources Assessment Report
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The Final EIR will be prepared after the public review period for this EIR has been completed. The Final EIR will include comments and recommendations received on the EIR during the public review period; a list of persons, organizations, and public agencies commenting on the EIR; written responses to significant environmental issues identified in the comments received; and any other relevant information added by the City.

2.7 Documents Incorporated by Reference
Pursuant to CEQA Guidelines Section 15150, this EIR has referenced several technical studies, analyses, and previously certified environmental documents. Information from these documents, incorporated by reference, is briefly summarized in the appropriate chapters and sections. The documents that were used to prepare this EIR include the following:
▪ City of Santee General Plan Update (2007; 2022; 2025) ▪ Santee Municipal Code (Code of Ordinances) (2025 [Updated]) ▪ County of San Diego Countywide Plan (General Plan) (2011) ▪ San Diego River Fire Hazard Mitigation Program: Fuels Treatment Plan (2026) These reference documents, in accordance with CEQA Guidelines Section 15150(b), are available for review at the following locations:

City of Santee General Plan
https://www.cityofsanteeca.gov/departments/planning-building/planning City of Santee Code of Ordinances
https://ecode360.com/43745546#43745546
County of San Diego Countywide Plan (General Plan)
https://www.sandiegocounty.gov/content/sdc/pds/generalplan.html San Diego River Fire Hazard Mitigation Program: Fuels Treatment Plan https://www.cityofsanteeca.gov/departments/fire-life-safety-services/san-diego-river-hazard-mitigation-grant-program 2 – INTRODUCTION
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2.8 Review of the Draft Environmental Impact Report
Upon completion of this Draft EIR, the City prepared and filed a Notice of Completion with the Governor’s Office of Land Use and Climate Innovation (LCI), State Clearinghouse to start the public review period (PRC Section 21161).

Concurrent with the Notice of Completion, the City distributed a Notice of Availability in accordance with CEQA Guidelines Section 15087. The Notice of Availability was mailed to the agencies, organizations, and individuals who previously requested in writing to receive a copy. The Notice of Availability was published in the Union Tribune newspaper and posted on the City’s website. During the public review period, this Draft EIR, including the appendices, is available for review at the following locations:

In Person:

Santee City Hall, Fire Administration (Building 5)
10601 Magnolia Avenue
Santee, California 92071
Santee City Hall, City Clerk’s Office (Building 3)
10601 Magnolia Avenue
Santee, California 92071
Santee Library
9225 Carlton Hills Boulevard #17
Santee, California 92071
Online:
https://www.cityofsanteeca.gov/services/project-environmental-review Agencies, organizations, individuals, and all other interested parties have the opportunity to comment on this Draft EIR during the public review period. Written or email comments on this Draft EIR should be addressed to the following:

Harley Wallace, Fire Chief
Santee City Hall, Fire Administration
10601 Magnolia Avenue
Santee, California 92071
Phone: 619.258.4100 ext. 207
Email: [email protected]
Upon completion of the public review period, written responses to all substantive environmental comments are prepared and made available prior to the public hearing on the Project before the City of Santee City Council, at which the Project, the Final EIR, and requested entitlements are considered. The comments received and the responses to those comments will be included as part of the record for consideration for the Project.

EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 3-1
3 Project Description
This chapter describes the objectives of the San Diego River Fire Hazard Mitigation Program: Fuels Treatment Plan (Project) and the Environmental Impact Report (EIR) and provides a detailed description of the Project characteristics. The City of Santee Fire Department has initiated the implementation of the Project, which has received grant funding from the Federal Emergency Management Agency and San Diego River Conservancy. The Project includes two phases, a planning and environmental review phase (Phase 1) and the implementation phase (Phase 2). This EIR evaluates the impacts associated with implementation of Phase 2.

3.1 Introduction
The City of Santee Fire Department has initiated the development of the Project to reduce wildfire risk in and around high-priority sites along the San Diego River corridor. This area lies within the wildland–urban interface (WUI) and includes critical public infrastructure, adjacent residential neighborhoods, and biologically sensitive habitats. The need for a targeted, ecologically conscious approach to vegetation management is underscored by increasing fire risk, invasive plant encroachment, and complex access and ownership constraints unique to the corridor.

The Fuels Treatment Plan (FTP) provides a framework for vegetation management across the approximately 300-acre Project Site and includes treatment strategies tailored to the site’s wildfire exposure, access conditions, existing vegetation, and proximity to sensitive resources. The plan is designed to protect communities, critical infrastructure, and sensitive resources by reducing wildfire risk through coordinated vegetation management across the Project Site. The FTP is designed to balance fire risk reduction with environmental stewardship. It emphasizes selective vegetation modification techniques that support defensible space and risk reduction while preserving ecological function, minimizing soil disturbance, and protecting sensitive resources.

3.2 Project Location
The approximately 300-acre Project Site composed of 29 distinct parcels and four (4) portions of rights-of-way 299.9- acre Project Site is located within 331 parcels along the San Diego River corridor that cuts through the center of the City of Santee as shown in Figure 3-1, Regional Location, and Figure 3-2, Project Location. The Project Site is located within Township 15 South, Range 1W, Sections 21, 22, 23, 27, 28, and 29 of the El Cajon and La Mesa, California

7.5-minute U.S. Geological Survey Quadrangle maps. The Project Site extends from Forester Creek at the western Project boundary to the City border with the unincorporated Lakeside community in the east, including the open space areas of Mast Park West, Mast Park Wetland Restoration Area, Mast Park East, Mission Creek, Walker Trails Open Space, and Walker Preserve. Vehicular access to the Project is via North Magnolia Avenue, the Lakeside Sports Park, and Mast Park. Multiple pedestrian access paths as well as residential and commercial developments border the Project.
1 Some of the Project parcels overlap due to differences in ownership. 3 – PROJECT DESCRIPTION
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 3-2

3.3 Environmental Setting

3.3.1 City of Santee
The City is located in the East County region of San Diego County, between the Pacific Ocean and the Cleveland National Forest. Encompassing about 17 square miles (approximately 10,615 acres) in eastern San Diego County, the City is located approximately 18 miles east of downtown San Diego. The City is bordered on the east by primarily residential development in the unincorporated San Diego County communities of Lakeside and Eucalyptus Hills and to the northeast by vacant land and active mining operations in Slaughterhouse Canyon. To the south, Santee is bordered by the City of El Cajon, unincorporated areas of County of San Diego, and the Gillespie Field Airport, and further to the southwest by Mission Trails Regional Park property located in the City of San Diego (City of Santee 2003).

3.3.2 Existing Project Site
The Project Site consists of 299.9 acres of the San Diego River corridor, where riparian and upland vegetation border residential neighborhoods, commercial development, public recreation areas, and transportation-related rights-of-way. This corridor includes sensitive areas such as wetlands, the San Diego River, and adjacent parcels within city boundaries. The Project Site is characterized by a mix of natural vegetation and non-native species, as well as proximity to residential and commercial structures. Land use within the Project Site includes Park/Open Space and Public land uses (City of Santee 2017). Land uses that immediately surround the Project Site include Planned Development, Residential land uses including Low-Medium Density Residential, Medium-Density Residential, Medium-High Residential, Neighborhood Commercial, Light Industrial, and General Industrial (City of Santee 2017).

Land Ownership
Land within the Project Site is primarily publicly owned by the City of Santee (approximately 207 acres), the County of San Diego (approximately 49 acres), and the Metropolitan Transit Development Board (approximately 5 acres).

City-owned parcels include both open space and actively managed recreational areas such as Mast Park and the Walker Preserve. The County of San Diego owns the central 49‑acre portion of the Project Site. The remaining land in the Project Site consists of privately owned parcels (14 acres) and rights‑of‑way (25 acres). The parcel ownership is shown in Figure 3-3, Parcel Ownership, and detailed in Table 1, Parcel Ownership, below.

Table 1. Parcel Ownership
Ownership Acreage
City of Santee 207
County of San Diego 49
Metropolitan Transit Development Board 5
Privately Owned 14
Publicly Owned Rights-of-way 25
Project Boundary
Date: 4/16/2026 User: cgardner Path: Z:\Projects\j1861101\MAPDOC\San Diego River Fire Hazard Mitigation Plan EIR\San Diego River Fire Hazard Mitigation Plan EIR.aprx Map: Regional Location Layout: Figure 3-1 Regional Location 1:24,000 0 260 520
Meters
0 1,000 2,000
n
Feet
Chula Vista
Solana
Beach Encinitas
San Diego
Carlsbad
Oceanside
Lemon Grove
La Mesa
El Cajon
Santee
Poway
San Marcos
Escondido
Vista
Imperial
Beach
Del Mar
Coronado
ÄÆ905
ÄÆ52
ÄÆ54
ÄÆ94
ÄÆ163
ÄÆ125
ÄÆ274
ÄÆ56
ÄÆ78
ÄÆ76
ÄÆ ÄÆ79
67 §¨¦805 §¨¦8
§¨¦15
S a n D i e g o
C o u n t y
Project Site
!(
^
SOURCE: USGS 7.5-Minute Series La Mesa and El Cajon Quadrangles Township 15S Range 1W Sections 21, 22, 23, 27, 28, 29
San Diego River Fire Hazard Mitigation Program EIR
Regional Location
FIGURE 3-1
3 – PROJECT DESCRIPTION
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INTENTIONALLY LEFT BLANK
Ä125 Ä67
Ä52
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ollo L n
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Copper Ridge
Rd
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anc
h
itos Pl
Carreta Dr
Conejo Rd
Edgemoo
r
D
4th St r
Via Nina
Delia
L
n
Ryder
R
d
Mavin Dr
I s aa c St
Hi
rsch Rd
Happy Ln
Cleary St
Bilteer Ct
Hi
nton
Dr
Dobyns Dr
Aq u illa Dr
Tuthill Way
Roe Dr
Rhone Rd
Bird St
Ramo Rd
Valor Pl
A
mster
Dr
Wharton Rd Doheny Rd
Dal e hurst Rd
Les Rd
Bellagio Rd
Ellen bee Rd
Pin
e
ry
G
r
ove
Larkridge St
Waynecrest Ln
Ashdale Ln
Gem Tree Way
P inon Pl
Calle
Dellago
E Hartland Ci r
Grand Fork Dr
Greencastle St
Placid View Dr
Taffy Ln
Pa s eo
Ladera
Ruffin Rd
Sunset Trail
Triana St
Sil vercreek Dr
Hartley Rd
Bu
n
dy D
r
Carita Rd
Dunbarton Rd
Stra thmore D r
Woodrose Ave
Pryor Dr
Stoyer Dr
Man d
evil el Rd
Leavesly Trail
Vomac Rd
Via Leslie
Lake Hill Rd
Ho bo l r
n
St
Timberlane Way
Settle R d
Heatherdale St
Northview Ln
Diam ondback Dr
Abraham Way
Via Francis
WheatlandsAve
Woodpark Dr
Bella
VistaSt
Biltee
r
Dr
Maranda Dr
Via Rita
Ramsgate Dr
Shadow Hil l Rd
Lake
Country Dr
W
Heaney
Cir
Abbeyfield Rd
Rai lroad Ave
Abbeywood Rd
Mariposa St
Atlas View Dr
Ca
m
b
u
ry
D
r
Pike Rd
E Heaney
Cir
Kenney St
Pennywood Rd Lutheran Way
Karerllyn Dr
Northcote Rd
Cottonwood Ave
Galston Dr
2nd St
Willowgrove Ave
Sevilla Dr
Buena Vista Ave
Domer Rd
Halberns
Blvd
Los
Ra
n
c
hito
s Rd
Town Center Pkwy
Graves
Ave
Civic
Center Rd
Olive
L
n
Mission Creek Dr
River Park Dr
Carlton Oa ks Dr
Lake Canyon Rd
Fanita Pkwy
N Woodside Ave
Carlton
Hills
Blvd
N Cu
y
a
m
aca
St
N
M
agnolia Ave
Mast Blvd
Prospect Ave
Cuyamaca St
El Nopal
Fanita Dr
Woodside Ave
Mission Gorge Rd
C
H
P
Officer
Christopher D. Lydon Memorial Fwy
San Clemente Canyon Fwy
Project Boundary
Date: 4/16/2026 User: cgardner Path: Z:\Projects\j1861101\MAPDOC\San Diego River Fire Hazard Mitigation Plan EIR\San Diego River Fire Hazard Mitigation Plan EIR.aprx Map: Project Location Layout: Figure 3-2 Project Location 0 900 1,800
n Feet
SOURCE: SanGIS 2023; Open Street Maps 2019
San Diego River Fire Hazard Mitigation Program EIR
Project Location
FIGURE 3-2
3 – PROJECT DESCRIPTION
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INTENTIONALLY LEFT BLANK
Project Boundary
Parcel Ownership
City of San Diego
City of Santee
County of San Diego
Metropolitan Transit Development Board
Privately Owned
Rights-of-way
Date: 4/16/2026 User: cgardner Path: Z:\Projects\j1861101\MAPDOC\San Diego River Fire Hazard Mitigation Plan EIR\San Diego River Fire Hazard Mitigation Plan EIR.aprx Map: Parcel Ownership Layout: Figure 3-3 Parcel Ownership 0 1,000 2,000
n Feet
SOURCE: SanGIS 2023, City of San Diego
San Diego River Fire Hazard Mitigation Program EIR
Parcel Ownership
FIGURE 3-3
3 – PROJECT DESCRIPTION
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INTENTIONALLY LEFT BLANK
3 – PROJECT DESCRIPTION
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 3-9

3.3.3 Wildfire Environment
The landscape of the Project Site is defined by a mosaic of riparian woodlands, wetlands, shrublands, non-native grasslands, and disturbed areas contained within a broad floodplain. The river bisects the community of Santee in an east–west orientation and forms one of the major hydrological and ecological features of eastern San Diego County. Surrounding the corridor are urban neighborhoods, commercial districts, transportation infrastructure, parks, and open space preserves, creating a landscape typical of a wildland–urban interface environment. As shown in Figure 3-4, Fire Hazard Severity Zones, portions of the Project Site are in areas designated as Moderate and High FHSZs, and bordered by areas designated as Moderate, High and Very High FHSZs to the north and south (CAL FIRE 2025a).

The Project Site is a typical riverine environment with native and non-native vegetation, dead biomass, stormdeposited debris, invasive vegetation, secondary channels and some open water. Non-native and dead vegetation within the Project Site is highly flammable. Although the Project Site is dominated by riparian vegetation, the broader fire environment in the region is shaped by the presence of flammable shrublands in surrounding foothills and by the region’s characteristic fire weather patterns. In San Diego County, inland valleys typically experience prolonged summer drying and periodic episodes of extreme offshore winds that can rapidly reduce fuel moisture and promote fast-moving wildfires (RCD of Greater San Diego County and San Diego County Fire Safe Council 2019; CAL FIRE 2025b). Human-caused ignitions are the most common type of ignition in the region (CAL FIRE 2025b); within the Project Site, public access and adjacency to development both contribute to elevated ignition potential. The San Diego River corridor therefore represents a complex fire environment defined by urban adjacency, variable fuel conditions, and exposure to regional fire weather events.

Climate and Fire Weather
The Santee area experiences a semi-arid Mediterranean climate characterized by hot, dry summers and mild winters with highly variable precipitation. Average annual rainfall at lower elevations in the county ranges from roughly 10 to 15 inches, with the majority occurring between December and March (RCD of Greater San Diego County and San Diego County Fire Safe Council 2019; CAL FIRE 2025b). Summer months are typically rainless, and prolonged dry periods contribute to the curing of fine fuels and the reduction of live fuel moisture across shrublands and grasslands. Peak temperatures in late summer and early fall frequently exceed 90°F in inland communities such as Santee, and fuel moisture typically reaches seasonal lows during this period.

A defining feature of the region’s fire weather is the occurrence of Santa Ana winds, which develop when warm, dry air flows from inland deserts toward the coast. These winds, which most commonly occur in late summer and fall, can reach sustained speeds of 25 to 35 mph on ridge tops and produce gusts exceeding 60 mph, traveling efficiently through east–west oriented drainages such as the San Diego River valley. Relative humidity during Santa Ana events often drops into the single digits, rapidly drying fine fuels and enabling fast, wind-driven fire spread (RCD of Greater San Diego County and San Diego County Fire Safe Council 2019; CAL FIRE 2025b). Seasonal winds in the inland foothills generally blow west to southwest during the summer but shift to northerly and easterly directions during fall and winter storm cycles, reinforcing the potential for wind alignment within the corridor (Eucalyptus Hills Fire Safe Council 2009). During such events, ignitions have the potential to develop into fast-moving, high-intensity fires capable of significant spotting and embers carried long distances through the WUI. 3 – PROJECT DESCRIPTION
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 3-10
Topography and Hydrology
The San Diego River corridor in Santee occupies a broad alluvial valley bounded by foothill terrain to the north and east. Elevations in the vicinity of the corridor range from roughly 300 feet along the river bottom to over 1,000 feet on adjacent ridgelines in neighboring communities (Lakeside Fire Safe Council 2024; Eucalyptus Hills Fire Safe Council 2009). Slopes in these upland areas can exceed 50°, creating steep gradients that can accelerate upslope fire runs under certain weather conditions.

The east–west orientation of the river reflects a broader regional drainage pattern that can channel Santa Ana winds toward the coast, increasing wind speeds within valley bottoms and contributing to rapid fire spread (CAL FIRE 2025b). Within the Project Site, the corridor includes active and secondary channels, wetlands, and riparian stands. Hydrologic conditions influence vegetation structure and fuel continuity in the corridor. Riparian species generally exhibit higher moisture content, though accumulated dead biomass, storm-deposited debris, and invasive vegetation can create locally high fuel loading. Periods of drought and high temperatures can exacerbate drying and flammability of vegetation.

Vegetation and Fuels
Vegetation in the Project Site reflects the composition typical of inland valleys and river corridors in western San Diego County. Riparian vegetation, including willows, cottonwoods, mulefat, and associated understory species, dominates the immediate river margins. Although riparian vegetation often retains higher moisture levels, it can contain dense stands of shrubs, branches, and debris, along with invasive species such as Arundo donax, which can contribute to elevated fire intensity (Eucalyptus Hills Fire Safe Council 2009). Non-native trees (palms, eucalyptus, tamarisk, pines) also present a hazard, especially when dry branches form a fuel ladder and/or when they completely or partially detach from the canopy.

Upland terraces and disturbed areas support coastal sage scrub dominated by California sagebrush (Artemisia californica), black sage (Salvia mellifera), and California buckwheat (Eriogonum fasciculatum), along with patches of non-native grasses that cure early in the fire season and readily carry surface fire. Mixed chaparral is present in the surrounding foothills but is less extensive within the corridor itself. However, chaparral in adjacent uplands can influence ember production, wind-driven spread, and fire intensity during extreme weather events.

Fire History and Ignitions
The California Department of Forestry and Fire Protection (CAL FIRE) fire perimeter database includes fires that meet a minimum threshold of over 10 acres in timber, 50 acres in brush, or 300 acres in grass. The lack of mapped fires in this database since 1950 is not for lack of historical ignitions just below the database listing threshold. The Santee Fire Department responded to 174 fires near the Project Site in 2024 and 2025 alone, 81 of which were on the Project boundary. On March 29, 2026, an approximately 10-acre fire occurred within the Project Site. The surrounding foothills also have a well-established fire history. The most notable regional event was the 2003 Cedar Fire, which burned more than 273,000 acres and demonstrated the potential for large, wind-driven fires to spread rapidly from the east (RCD of Greater San Diego County and San Diego County Fire Safe Council 2019).

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Date: 4/16/2026 User: cgardner Path: Z:\Projects\j1861101\MAPDOC\San Diego River Fire Hazard Mitigation Plan EIR\San Diego River Fire Hazard Mitigation Plan EIR.aprx Map: Figure 3-4 Fire Hazard Severity Zones Layout: Figure 3-4 Fire Hazard Severity Zones SOURCE: Maxar 2024; CalFire 2025
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EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 3-13
Across the San Diego Unit, CAL FIRE responds to approximately 510 wildland fires per year, with an average of 15,000 acres burned annually when the extreme fire-siege years of 2003 and 2007 are excluded (CAL FIRE 2025b).

Large fire years (i.e., those in which more than 20,000 acres burn) occur every 7 years on average, with recurrence intervals ranging from 1 to 22 years. The 2003 and 2007 fire sieges together burned over 500,000 acres countywide, underscoring the region’s potential for extreme fire growth under severe wind and weather conditions (CAL FIRE 2025b).

Human-caused ignitions, including vehicle fires, debris burning, equipment use, and campfires, are the predominant ignition sources in the region (CAL FIRE 2025b). Ignitions affecting the Project area stem from the corridor’s urban adjacency, recreational access, and use by unhoused populations in certain segments and are expected to increase.

3.4 Project Objectives
California Environmental Quality Act Guidelines Section 15124(b) requires project descriptions to contain a statement of objectives that includes the underlying purpose of the proposed project. The objectives of the Project are identified below:

Objective 1 – Define strategy for specific fuel treatment zones for reducing hazardous fuel loads within the San Diego River corridor.

Objective 2 – Enhance community safety within the City of Santee through the reduction of wildfire risk.

Objective 3 – Reduce horizontal and vertical continuity of fuels and hazardous fuel loads through the removal of non-native and invasive species.

Objective 4 – Reduce ignition potential and fire intensity within the San Diego River corridor.

3.5 Fuels Treatment Plan
The FTP proposes the implementation of fuel treatment and vegetation management in the Project Site, through identifying treatment zones and vegetation management techniques within the Project Site, as described below.

For purposes of this EIR and the Project, vegetation management refers broadly to the actions taken to modify, reduce, or maintain vegetation in order to lower wildfire risk within the Project Site. Vegetation treatment describes the specific prescribed methods used to accomplish that management such as hand labor, mechanical equipment, and chemical applications. Treatment activities are the on-the-ground implementation steps associated with those methods, including cutting, trimming, mowing, thinning, biomass removal, and other field actions necessary to meet the vegetation management objectives. These terms are used throughout the EIR to describe how vegetation would be modified to reduce hazardous fuel loads while protecting ecological and recreational functions of the corridor.

Treatment Zones
As shown in Figure 3-5, Treatment Zones, vegetation management recommendations for the Project Site are organized into three zones. Each zone provides a framework to reduce fuel continuity while protecting the hydrologic, ecological, and recreational functions of the river corridor. Treatments vary in intensity across zones but are designed to be ecologically conscious and appropriate for a highly used, hydrologically sensitive environment.

In each zone, vegetation management consists overall of the removal of all fine fuels, leaf litter, woody debris, treating or removing all non-native and dead vegetation including invasive species and shrubs or trees with 3 – PROJECT DESCRIPTION
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 3-14
extensive dead or desiccated material, and treatment or removal of accumulations deposited during storm events.

Table 2 below shows the total acreages of each zone.

Throughout Zone 1, all fine fuels, dead vegetation, leaf litter, and woody debris would be treated or removed.

Grasses would be trimmed/mowed to a height not to exceed 4 inches. Shrubs would be thinned to reduce horizontal continuity to a residual surface coverage of approximately 30%. Shrubs or other surface vegetation (e.g., ground cover) would be treated to reduce vertical continuity beneath tree canopies to achieve a separation of three times the height of the surface vegetation. Non-native, invasive, or flammable plant species would be removed wherever present. Ladder fuels would also be addressed by trimming low tree branches (in addition to treating shrubs or surface vegetation beneath tree canopies). All trimming activities would be done to industry standards (ISA, American National Standards Institute [ANSI]) to minimize likelihood of plant death. In addition, clearance would be maintained around fences, propane tanks, accessory structures, and other features susceptible to ignition, as applicable. Live and healthy native species may be treated as allowed (e.g., trimmed or removed) through additional permitting only.

Vegetation management in Zone 2 consists of treating or removing all non-native and dead vegetation, including invasive species and shrubs or trees with extensive dead or desiccated material. trimming dead and dying branches from native vegetation to reduce ladder fuels and minimize the potential for tree canopy torching. Shrubs would be thinned to reduce horizontal continuity to a residual surface coverage of approximately 50%. Shrubs or other surface vegetation (e.g., ground cover) would be treated to reduce vertical continuity beneath tree canopies to achieve a separation of three times the height of the surface vegetation. Grasses would be trimmed/mowed to a height not to exceed 4 inches. All trimming activities would be done to industry standards (ISA, ANSI) to minimize likelihood of plant death. Vegetation removal and treatment in this zone is intended to reduce fire intensity and rate of spread while maintaining ecological structure where feasible. Live and healthy native species may be treated (e.g., trimmed or removed) as allowed or through additional permitting only.

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Potential Non-Native/Dead and Dying Vegetation Removal Areas Date: 7/14/2026 User: jgreenstein Path: Z:\Projects\j1861101\MAPDOC\San Diego River Fire Hazard Mitigation Plan EIR\San Diego River Fire Hazard Mitigation Plan EIR.aprx Map: Figure 2 Project Components Layout: Figure 3-5 Treatment Zones 0 500 1,000
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Zone 3
Zone 3 encompasses the broader vegetated areas of the river corridor (outside Zones 1 and 2), including most riparian zones, floodplain terraces, and open space areas such as portions of Mast Park and Walker Preserve.

Removal and other treatment of live and healthy native species would not occur within Zone 3.

Table 2. Acreage of Treatment Zones
Zone Total Acres
1 9.2
2 22.5
3 268.2
Total 299.9
Any removal or trimming of native vegetation within Zones 1 and 2 shall occur only following acquisition of required permits. Until such permits are secured, vegetation management in these zones will focus solely on non-native species and dead or dying vegetation. Following completion of permitting, native vegetation treatments in Zone 1 and 2 may proceed as needed to meet the fire protection objectives.

Vegetation management activities in Zone 3 would be limited to removal of dead, dying, or non-native species.

Removal or treatment of live, healthy native vegetation would not occur within Zone 3. Accordingly, permits associated with native vegetation treatment are not anticipated to be required for this zone.

Vegetation Management Techniques
Vegetation management within the Project Site would rely on a combination of techniques aimed at altering existing vegetation to reduce the potential for ignitions and modify fire behavior. While the FTP allows for use of any vegetation management techniques in each zone, method selection would depend on site conditions, access availability/condition, target vegetation types, zone designation, proximity to sensitive resources, and the potential for soil or habitat disturbance in sensitive areas. The following section discusses each vegetation management technique that may be implemented in the Project Site:
▪ Hand Labor (e.g., hand cutting, trimming). Hand labor treatments involve trimming, cutting, or removing trees, shrubs, and grasses by hand or using handheld equipment. ▪ Mechanical (e.g., mowing, masticating). Mechanical techniques include all fuel reduction methods that employ motorized heavy equipment to remove or alter vegetation, typically across larger areas. ▪ Chemical (e.g., EPA approved herbicide). Chemical techniques involve the use of herbicides to kill vegetation or prevent growth and are typically used in combination with other types of fuel reduction treatments.

Herbicides do not remove any vegetation from a treatment area; therefore, dead plant material remains unless otherwise treated. Application of herbicides and other chemicals is typically performed by hand, and can include sponging, spraying, or dusting chemicals onto undesirable vegetation. Hand application provides flexibility in application and is ideally suited for small treatment areas. 3 – PROJECT DESCRIPTION
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 3-18
Each vegetation management technique would implement the applicable best management practices (BMPs) as outlined in Section 3.6 of this EIR.

Biomass Removal
Biomass removal would depend on the type of treatment proposed. Mechanical treatments, such as mastication or mowing, may generate biomass that is inherently disposed of as part of the treatment itself (i.e., biomass is chipped or thatched). Chemical treatments generally produce little to no biomass at the time of application, but any subsequent cutting of dead material resulting from herbicide treatments would require disposal. Methods available for biomass removal include off-site transportation to a green waste facility, on-site broadcast of chips, lop-andscatter (crews cut material into shorter lengths and scatter it evenly, so it lies as close to the ground as possible), cranes and helicopters and species specific disposal (for invasive or weed species). Disposal approach would depend on access, vegetation type, and the volume of material generated. Off-site removal shall be prioritized where feasible due to its long-term hazard reduction benefits. Chipping may be used where equipment access is available, and vegetation consists of suitable woody material. Lop-and-scatter shall be limited to small, constrained areas.

Access and Staging
Access to the Project Site would vary during Project implementation. Potential access routes for vegetation management activities are shown in Figure 3-6, Access Routes. The routes are broken into two categories depending on the capability of the road to support different equipment types:
▪ Class 1: Capable of supporting full-size vehicles and associated equipment (e.g., chippers) and equipment trailers. ▪ Class 2: Capable of supporting smaller vehicles (e.g., bobcats, side-by-sides).

During Project implementation, routes would be confirmed by the vegetation management contractor prior to use.

Some access routes would require rights of entry based on land ownership. In addition to the routes identified in Figure 3-6, it is anticipated that overland travel by foot would be conducted by field crews along disturbed land to access vegetation management work locations. The proposed Project would prioritize existing roads and trails, minimizing the need for new disturbance.

To the extent feasible, staging areas for Project equipment would be located away from residential areas and popular trailheads to reduce noise, dust, and congestion. When mechanical equipment is required, operators shall use designated entry points and avoid sensitive resource areas or high-use recreation corridors. Access via public roadways may also be necessary. In such cases, the selected contractor will be responsible for traffic control to maintain safe working conditions.

Maintenance
The Project includes the ongoing maintenance of the Project Site to ensure that initial vegetation treatments continue to reduce wildfire hazard over time. Maintenance activities are intended to (1) prevent the re-accumulation of hazardous fuels, (2) sustain desired vegetation structure and species composition, (3) protect initial treatment investments, and (4) improve firefighter access and suppression effectiveness during wildfire events. The City will be responsible for conducting biannual inspections, determining maintenance needs for each zone, coordinating or engaging maintenance crews, and ensuring compliance with the FTP.

Maintenance intervals will vary depending on vegetation type, treatment zone, and treatment technique. The Project Site will be inspected biannually to determine maintenance needs. It is expected that maintenance within Zones 1 3 – PROJECT DESCRIPTION
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 3-19
and 2 will occur at least once annually. Maintenance within Zone 3 will be determined during biannual inspections and will be based on the establishment (or re-establishment) of non-native plant species, vegetation mortality (dead plant material presence), and accumulation or deposition of combustible debris (including dead and dying nonnative and native vegetation). The frequency of maintenance activities in Zone 3 will be dependent on observations made during biannual inspections. It is expected that approximately one-quarter of the total Project Site will be maintained annually to preserve reduced hazardous fuel conditions.

Maintenance of the plan area will use the techniques outlined in the FTP (hand labor, mechanical, and chemical).

Biomass disposal associated with maintenance activities will follow the BMPs identified in Section 3.6.

3.6 Best Management Practices
The following BMPs would be applied to the Project where applicable and are considered part of the Project:

Hand Labor (referred to as “Hand Labor BMP-#” in this EIR) Ensure equipment operators and Project personnel are properly trained in equipment use.

Ensure that vehicles and equipment arrive at the treatment area clean and weed-free.

An International Society of Arboriculture (ISA) Certified Arborist shall conduct all trimming according to International Society of ANSI A300 standards.

To minimize soil disturbance, leave stumps from removed trees and shrubs intact, with stump heights not exceeding 6 inches, as measured from the uphill side; treat stump-sprouting species using the cut and daub technique described in Section 3.3.3.2 of the FTP.

Protect retained trees and vegetation from tool and equipment damage.

Service and fuel tools only in areas that will not allow grease, oil, fuel, or other hazardous materials to pass into streams or retained vegetation.

Remove from the site and properly dispose of all refuse, litter, trash, and non-vegetative debris resulting from vegetation treatment operations, and other activity in connection with vegetation treatment operations.

Mechanical (referred to as “Mechanical BMP-#” in this EIR) Utilize low ground-pressure equipment, to the extent feasible.

Ensure equipment operators and Project personnel are properly trained in equipment use.

Ensure that vehicles and equipment arrive at the treatment area clean and weed-free.

Control fugitive dust resulting from equipment use by watering disturbed areas.

Protect retained trees and vegetation from potential damage resulting from heavy equipment use.

To minimize soil disturbance, leave stumps from removed trees and shrubs intact, with stump heights not exceeding 6 inches, as measured from the uphill side.

Limit the size and quantity of equipment to that which is necessary to meet the identified vegetation management standard.

Wherever possible, limit heavy equipment staging and placement to existing roads and access routes.

Regrade or recontour any areas subject to soil disturbance from heavy equipment, including dragging or skidding of trees or other material.
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EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 3-20
Where work is unavoidable in saturated soils or along creek banks, hand place temporary high-density flexible rubber mats to distribute equipment load and protect soils.

Use temporary rubber mats or plates to cross over jurisdictional creek areas.

Use temporary rubber mats or pads when driving across vegetated areas to distribute vehicle weight and minimize vegetation removal and soil disturbance.

Equipment used for mechanical treatment shall not operate on hillsides with slopes greater than 50% (27°).

Service and fuel heavy equipment only in areas that will not allow grease, oil, fuel, or other hazardous materials to pass into streams or retained vegetation.

Ensure that hazardous materials spill kits are available on all heavy equipment.

To the fullest extent possible and with due consideration given to topography, lean of trees, utility lines, local obstructions, and safety factors, trees shall be felled away from structures, landscape improvements (fences, signage), streams, sensitive biological resources areas, and retained trees. Cabling, sectional removal, or other felling techniques shall also be employed, where feasible, to minimize impacts to streams, sensitive biological resource areas, and retained trees.

Remove and fell trees according to ISA and ANSI A300 standards.

Chemical (referred to as “Chemical BMP-#” in this EIR)
Herbicide use shall be considered only when other treatment techniques are determined to be infeasible or ineffective in achieving desired management and maintenance standards.

Santee Fire Department shall consult with a state-licensed pest control adviser (PCA) and/or the San Diego County agricultural commissioner to identify the appropriate site-specific herbicide application approach to meet vegetation management standards.

The timing of herbicide applications shall be considered to minimize impacts to adjacent retained vegetation and nearby resources (typically between June 15 and November 15, with a potential extension through December 31 or until local rainfall greater than 0.5 inches is forecasted within a 24-hour period from planned application). Herbicide application shall not occur during winds that exceed 7 miles per hour.

Only herbicides that have been approved for aquatic use by the U.S. Environmental Protection Agency and are registered for use by the California Department of Pesticide Regulation would be used for aquatic vegetation control work.

Herbicide application shall be consistent with Federal Insecticide, Fungicide, and Rodenticide Act label instructions and use conditions issued by the U.S. Environmental Protection Agency, California Department of Pesticide Regulation, and the San Diego County agricultural commissioner.

The lowest recommended rate to achieve vegetation management objectives of both herbicides shall be utilized to achieve desired control.

An appropriate indicator dye shall be added to the tank mix to help the applicator identify areas that have been treated and better monitor the overall application.

No application to plants whose base is submerged in stream channels shall occur.

Safe procedures for transporting, mixing, and loading herbicides shall be followed.

The use of foliar (spray) applications shall be minimized, prioritizing localized or direct applications.

Herbicides shall not be applied within 25 feet of a perennial stream or water body.

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Date: 4/16/2026 User: cgardner Path: Z:\Projects\j1861101\MAPDOC\San Diego River Fire Hazard Mitigation Plan EIR\San Diego River Fire Hazard Mitigation Plan EIR.aprx Map: Figure 3-6 Access Routes Layout: Figure 3-6 Access Routes 0 500 1,000
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FIGURE 3-6
3 – PROJECT DESCRIPTION
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 3-22

INTENTIONALLY LEFT BLANK
3 – PROJECT DESCRIPTION
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 3-23
Slope Stability/Erosion (referred to as “Slope Stability/Erosion BMP-#” in this EIR) Avoid work during and immediately following wet periods when soils are saturated.

Where work is unavoidable in saturated soils or along creek banks, hand place high-density flexible rubber mats to distribute equipment load and protect soils.

No vehicle or equipment is used on roads when roads are wet or muddy.

Equipment used for mechanical treatment shall not operate on hillsides with slopes greater than 50% (27°).

No removal of stumps or root balls of cut material. The root systems of cut vegetation shall be left intact as much as possible.

Mature, native tree canopy will be left intact.

Treated vegetation shall be masticated or chipped and spread back onto the treatment area where slopes do not exceed 45° (100% slope or 1:1 slope).

On slopes exceeding 45° (greater than 100% slope or greater than 1:1 slope), cut tree branches can be spread onto the surface to help prevent chips from sliding down the slope during precipitation.

Only hand labor shall be performed within 25 feet of a wetland or water body. Only hand labor or chemical spot treatment shall be performed between 25 and 100 feet of a perennial stream or water body.

Areas of bare soil created by fuel reduction treatments shall be covered entirely with chipped or masticated vegetation.

Water Quality (referred to as “Water Quality BMP-#” in this EIR) Mechanical tools, equipment, and vehicles shall be routinely inspected to ensure that fuel, oil, and other fluids and lubricants are not leaking.

Tool and equipment refueling shall be conducted in identified re-fueling areas in staging or parking areas that provide secondary containment located away from watercourses.

Provide spill kits at refueling areas.

Store tools, lubricants, and fuels away from watercourses, ensuring secondary containment and clear labeling.

Stockpiling of vegetative material and equipment will be limited to designated upland areas outside of aquatic resources to the maximum extent practicable. Any temporarily staged materials will be placed to avoid contact with waters and minimize the potential for sediment discharge, and all stockpiled materials and equipment will be removed from the site at the end of each workday.

Pests and Pathogens (referred to as “Pests and Pathogens BMP-#” in this EIR) Schedule all oak trimming or removal, where permitted, between October and March to avoid the goldspotted oak borer adult flight period and minimize wound-attraction.

Avoid trimming or ground disturbance during or immediately after wet periods (rainfall greater than 0.5 inches within a 24-hour period), when pest and pathogen transmission risk is highest.

Clean and sanitize vehicles, equipment, tools, footwear, and clothes before arriving at a project site or when leaving an area with infestations of invasive species. Sanitize all hand tools and chainsaws that come into contact with infected material, or material suspected to be infected, before leaving a work site using a 10% bleach solution or 70% isopropyl alcohol.

Remove all soil/mud and plant debris from boots, tracked equipment, tires, and undercarriages before entering and leaving a site, especially when working near the San Diego River or wetlands. 3 – PROJECT DESCRIPTION
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 3-24
Treated woody vegetation shall be chipped or masticated and spread on site to a depth not exceeding 6 inches, unless material shows signs of active pest infestation.

Do not stage or transport cut wood from host species (e.g., oak, sycamore, willow) unless it is chipped, debarked, solarized, or disposed of at an approved facility.

Cover all infested wood in clear plastic tarps sealed at the edges for at least 6–12 months if immediate removal is not feasible.

Never move unprocessed wood or logs off site from the Project area unless securely covered and delivered to an approved biomass, composting, or landfill facility.

Report any suspected pest infestations (e.g., exit holes, staining, sap flow, crown dieback) to the Project manager immediately.

Fire Protection (referred to as “Fire Protection BMP-#” in this EIR) During operations that involve the use of any vehicle, machine, tool or equipment powered by an internal combustion engine operated on hydrocarbon fuels, provide and maintain suitable and serviceable tools for firefighting purposes. Equipment shall be located at a point accessible in the event of a fire and shall include one backpack pump-type fire extinguisher filled with water, two axes, two McLeod fire tools, and a sufficient number of shovels so that each employee at the operation can be equipped to fight fire.

Ensure that all equipment with an internal combustion engine using hydrocarbon fuels is equipped with a spark arrestor, as defined in California Public Resources Code Section 4442.

Establish communication procedures with staff and contractors for reporting fires or call 911 in emergencies.

Restrict the use or timing of use of tools or equipment with the potential to generate heat or sparks during Red Flag Warnings and High to Extreme Fire Danger days.

Identify staging areas prior to initiating operations. Staging areas shall be contained within already disturbed areas or non-vegetated areas (e.g., roads, parking lots) and shall account for vehicle parking and tool/equipment storage.

Air Quality (referred to as “Air Quality BMP-#” in this EIR) Control fugitive dust resulting from equipment use as needed by watering disturbed areas and ingress/ egress locations.

Maintain all trucks and equipment in good working order and compliant to current emission standards, including Tier 4 Final Air Pollution Control District – San Diego County required equipment and Best Available Control Technology, where possible.

Avoid work during unfavorable weather conditions, including excessive wind/Santa Ana events, to reduce unnecessary contributions to dust and particle suspension.

Securely cover all material (e.g., mulch, trees, tree debris) transported off site.

Limit the size and quantity of equipment to that which is necessary to meet the identified vegetation management standard.

Limit traffic speeds on dirt roads to 15 miles per hour.

Clean construction vehicles and equipment to prevent dust, silt, mud and dirt from being tracked onto paved roadways.

Limit vehicle idling time to a maximum of 2 minutes for diesel-powered equipment and 5 minutes for all other vehicles and equipment, except where idling is required for the equipment to perform its task. 3 – PROJECT DESCRIPTION
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 3-25
Post a publicly visible sign with the telephone number and person to contact at the lead agency regarding dust complaints. This person shall respond and take corrective action within 48 hours. The Air District’s phone number shall also be visible to ensure compliance with applicable regulations.

Recreation Resources (referred to as “Recreation Resources BMP-#” in this EIR) Restore disturbed recreation areas to pre-operation conditions (e.g., clear blocked trails, recontour damaged trails to minimize the potential for erosion or the creation of unauthorized trails).

Repair, replace, or reinstall damaged, removed, or relocated park infrastructure (e.g., signs, gates).

Minimize the extent or duration of closures by phasing work and/or conducting work outside of peak visitation periods, where feasible.

Where feasible, conduct operations on weekdays during daytime hours (7 a.m. to 7 p.m.).

Control public access by posting detours, installing and maintaining appropriate and adequate signage, using flaggers/monitors where necessary, closing work areas via exclusionary fencing, and providing necessary monitoring/patrolling staff to ensure access control measures are maintained and effective.

Disseminate information regarding planned Project activities on the City’s website, social media, in-park signage, local newspaper, and via outreach to regular known user groups.

Noise (referred to as “Noise BMP-#” in this EIR)
All noise-producing Project equipment and vehicles using internal combustion engines shall be equipped with mufflers, air-inlet silencers where appropriate, and any other factory-installed shrouds, shields, or other noise-reducing features in good operating condition that meet or exceed original factory specification.

Mobile or fixed “package” equipment shall be equipped with shrouds and noise control features that are readily available for that type of equipment.

Mobile equipment staging, parking, maintenance areas, and construction equipment shall be located as far as practicable from noise-sensitive receivers.

The on-site construction supervisor shall have the responsibility and authority to receive and resolve noise complaints. A clear appeal process to the Owner shall be established prior to construction commencement that shall allow for resolution of noise problems that cannot be immediately solved by the site supervisor.

Biological Resources (referred to as “Biological Resources BMP-#” in this EIR) Retain at least 75% of the overstory and 50% of the understory canopy of native riparian vegetation within 100 feet of perennial streams and 50 feet of intermittent streams during thinning activities.

3.7 Required Project Approvals
This EIR covers all state and local government and quasi-government approvals that may be needed to implement the Project, whether or not they are explicitly listed in this section or elsewhere in this EIR (14 CCR 15124[d]).

Regulatory and environmental compliance for the Project will include coordination and consultation with several state and federal agencies to issue all required permissions for the Project, as well as review and approval by the City Council in accordance with the City’s General Plan and Municipal Code. 3 – PROJECT DESCRIPTION
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 3-26
City Council
▪ Consideration of the San Diego River Hazard Mitigation Program: Fuels Treatment Plan. The City Council will consider whether to adopt, revise, or reject the San Diego River Hazard Mitigation Program: Fuels Treatment Plan.
▪ Consideration of EIR. The City Council will consider whether to certify or reject this EIR, along with appropriate California Environmental Quality Act findings and the mitigation monitoring and reporting program.

Local Agencies
▪ County of San Diego Right-of-Entry Permit
State Agencies
▪ California Department of Fish and Wildlife Lake and Streambed Alteration Agreement ▪ Regional Water Quality Control Board Clean Water Act Section 401 Water Quality Certification ▪ Caltrans Right-of-Way Encroachment Permit
Federal Agencies
▪ U.S. Army Corps of Engineers Regional General Permit 41 ▪ National Historic Preservation Act Section 106 Consultation ▪ Federal Emergency Management Agency Record of Environmental Consideration approving National Environmental Policy Act Programmatic Environmental Assessment Consistency Memorandum ▪ U.S. Fish and Wildlife Service Biological Opinion or Concurrence EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4-1
4 Environmental Analysis
Approach to the Environmental Analysis
This Draft Environmental Impact Report (EIR) evaluates and discloses the environmental impacts associated with the San Diego River Hazard Mitigation Program: Fuels Treatment Plan Project (Project), in accordance with the California Environmental Quality Act (CEQA) (Public Resources Code Section 21000, et seq.) and the State CEQA Guidelines (14 CCR 15000 et seq.). Sections 4.1 through 4.6 of this Draft EIR present a discussion of environmental setting, regulatory setting, significance criteria, environmental impacts associated with the Project, mitigation measures to reduce the level of impact, and residual level of significance (i.e., no impacts would remain significant and unavoidable after application of all feasible mitigation measures). Issues evaluated in these sections consist of the environmental topics identified for review in the Notice of Preparation prepared for the Project (see Appendix A of this Draft EIR) and in Section 2.5.3, Environmental Issues Determined to be Potentially Significant, of this Draft EIR. Chapter 5, Effects Found Not to Be Significant, of this Draft EIR briefly describes potential environmental effects that were determined not to be significant and therefore are not discussed in further detail in the EIR, as required by CEQA Guidelines Section 15128. Chapter 6, Other CEQA Considerations, of this Draft EIR presents an analysis of the Project’s impacts considered together with other past, present, and probable future projects producing related impacts (cumulative impacts), as required by State CEQA Guidelines Section 15130, and includes an analysis of the Project’s growth-inducing impacts, as required by CEQA Section 21100(b)(5). Chapter 7, Alternatives, of this Draft EIR presents a reasonable range of alternatives and evaluates the environmental effects of those alternatives relative to the Project, as required by State CEQA Guidelines Section 15126.6.

Sections 4.1 through 4.6 of this Draft EIR include the following components:
▪ Existing Conditions: Provides information describing the existing environmental conditions on the Project Site and in the surrounding area as appropriate, in accordance with State CEQA Guidelines Section 15125.

This setting discussion describes the conditions that existed when the Notice of Preparation was posted for public review and submitted to the State Clearinghouse. ▪ Relevant Plans, Policies, and Ordinances: Provides a discussion of existing federal, state, regional, and local regulations, plans, policies, and ordinances applicable to the Project. ▪ Thresholds of Significance: Provides criteria for determining the significance of Project impacts for each environmental issue.
▪ Impact Analysis: Provides a discussion of the characteristics of the Project that may have a physical impact on the environment, analyzes the nature and extent to which the Project is expected to change the existing environment, and indicates whether the Project’s impacts would meet or exceed the level of significance thresholds. ▪ Mitigation Measures and Level of Significance After Mitigation: Mitigation measures are identified, as feasible, to avoid, minimize, rectify, reduce, or compensate for significant or potentially significant impacts, in accordance with the State CEQA Guidelines Section 15126.4. A “less-than-significant” impact is one that would not result in a substantial adverse change in the physical environment. A “potentially significant” impact or “significant” impact is one that would result in a substantial adverse change in the physical environment; both are treated the same under CEQA in terms of procedural requirements and the need to identify feasible mitigation. Significant and unavoidable impacts are identified as appropriate in accordance with State CEQA Guidelines Section 15126.2(c).
4 – ENVIRONMENTAL ANALYSIS
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4-2

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4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-1

4.1 Biological Resources
This section describes the existing biological resources conditions of the San Diego River Fire Hazard Mitigation Program: Fuels Treatment Plan (Project) Site and vicinity, identifies associated regulatory requirements, evaluates potential impacts, and identifies mitigation measures, if necessary to reduce or avoid significant impacts, related to implementation of the Project.

In addition to the documents incorporated by reference (see Section 2.7 of Chapter 2, Introduction, of this Environmental Impact Report), the following analysis is based, in part, on the following source:
▪ Biological Resources Letter Report, prepared by Dudek in April 2026 (Appendix B)

4.1.1 Existing Conditions
The approximately 300-acre Project Site is within the San Diego River Corridor and includes sensitive areas such as wetlands and the San Diego River. The Project Site is characterized by a mix of natural vegetation and non-native species, as well as proximity to residential and commercial structures. The following sections describe the existing biological resources within the Project Site and potentially occurring within adjacent areas associated with the San Diego River.

4.1.1.1 Vegetation Communities and Land Covers
Vegetation community classifications within the Project Site follow Holland (1986), as revised by Oberbauer et al. (2008). Some vegetation communities were added or given additional descriptions to identify unique characteristics or highly dominant species within certain communities. The Project Site is characterized by a mix of natural as well as non-native vegetation communities and land cover types. A total of 19 vegetation communities (including subforms) and/or land cover types were identified in the Project Site during the biological reconnaissance surveys, consisting of 11 native vegetation communities and 8 non-native vegetation communities or land cover types. Of the 19 vegetation communities, 12 are considered wetland/riparian habitats. Acreages for each vegetation community or land cover type are provided in Table 4.1-1 below, and their spatial distributions are shown in Figures 4.1-1A through 4.1-1E, Biological Resources. Descriptions of each vegetation community and land cover type are included in Section 4.1 of Appendix B of this Draft Environmental Impact Report (EIR).

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-2
Table 4.1-1. Vegetation Communities and Land Covers Within the Project Site Vegetation Community/Land Cover Type1 Project Site (Acres) Sensitive (Y/N)2 Native Vegetation Communities
Riparian and Bottomland Habitat
Southern Arroyo Willow (Salix lasiolepis) Riparian Forest 9.00 Y Southern Cottonwood–Willow (Populus spp.- Salix spp.)
Riparian Forest
122.08 Y
Southern Riparian Scrub 1.22 Y
Southern Willow (Salix spp.) Scrub 17.26 Y
Mulefat (Baccharis salicifolia) Scrub 0.44 Y
Open Water 42.89 Y
Non-vegetated Channel or Floodway 0.08 Y
Subtotal 192.97 N/A
Bog and Marsh
Coastal and Valley Freshwater Marsh 29.71 Y
Emergent Wetland 3.85 Y
Subtotal 33.56 N/A
Woodlands
Coast Live Oak (Quercus agrifolia) Woodland (including Open subform)

1.84 Y
Scrub and Chaparral
Diegan Coastal Sage Scrub (including Baccharis-dominated subform)

27.76 Y
Subtotal of Native Vegetation Communities 256.13 N/A
Non-native Vegetation Communities and Land Covers
Riparian and Bottomland Habitat
Non-native Riparian 0.76 Y
Disturbed Wetland 2.75 Y
Tamarisk Scrub 1.49 Y
Subtotal 5.00 N/A
Woodlands
Non-native Woodland 0.48 N
Eucalyptus Woodland 2.29 N
Subtotal 2.77 N/A
Grasslands
Non-native Grassland 1.85 Y
Disturbed or Developed Areas
Disturbed Habitat 27.71 N
Urban/Developed 6.52 N
Subtotal 34.23 N/A
Subtotal of Non-native Vegetation Communities/Land Covers 43.85 N/A Grand Total 299.93 N/A
Notes: N/A = Not Applicable. Totals may not sum due to rounding. 1 According to Oberbauer et al. (2008).
2 Considered sensitive under the Draft Santee MSCP Subarea Plan (City of Santee 2025).

Mission Gorge Rd
Fanita Dr
Carlton Hills Blvd
Fanita Pkwy
Gorge Pl
Gorge Ct
Sunwood Dr
Double M
R
d
Singing
Wood Way
Carlton Oaks Dr
Calle del Verde
Gorge Ave
Willowgrove Ave
Ä125
DW
CLOW
CLOW
CLOW
CSS
CSS

CSS CSS
CSS
CSS
CSSB
CSSB
CSSB
CSSB
CSSB
DEV
DEV
DEV
DEV
DH
DH
DH DH
DH
DH
DH
DH
DH
DH
DH
DH
DH
EUC
EUC
EUC
EUC
EW
EW
EW
EW
EW
FWM
FWM
FWM
FWM
FWM
FWM
FWM
FWM
MFS
MFS
MFS
NNR
NNW
NNW
NVC
NVC
OW
SCWRF
SCWRF
SCWRF
SCWRF
SCWRF
SCWRF
SWS
SWS
SWS
SWS
SWS
SWS
SWS
Date: 4/28/2026 User: cgardner Path: Z:\Projects\j1861101\MAPDOC\San Diego River Fire Hazard Mitigation Plan EIR\San Diego River Fire Hazard Mitigation Plan EIR.aprx Map: Figure 4.1 Biological Resources Layout: Figure 4.1-1 Biological Resources 0 150 300
n
Feet
Project Boundary
Invasive Plant Species Proposed for Removal
Potential Invasive Species/Dead and Dying Tree
Removal Areas
Cortaderia selloana (Uruguayan pampas grass)
Special-Status Plant Species
Iva hayesiana (San Diego marsh-elder)
Vegetation Communities and Land Covers
Sensitive Riparian Vegetation Communities
Sensitive Upland Vegetation Communities
CLOW, Coast Live Oak Woodland
CSS, Diegan Coastal Sage Scrub
CSSB, Diegan Coastal Sage Scrub: Baccharisdominated
DEV, Urban/Developed
DH, Disturbed Habitat
DW, Disturbed Wetland
EUC, Eucalyptus Woodland
EW, Emergent Wetland
FWM, Coastal and Valley Freshwater Marsh
MFS, Mule Fat Scrub
NNR, Non-Native Riparian
NNW, Non-Native Woodland
NVC, Non-Vegetated Channel or Floodway
OW, Open Water
SCWRF, Southern Cottonwood-Willow Riparian Forest
SWS, Southern Willow Scrub
A
B
C
D
E
SOURCE: Vantor 2025; Open Street Map 2025
San Diego River Fire Hazard Mitigation Program EIR
Biological Resources
FIGURE 4.1-1A

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-4

INTENTIONALLY LEFT BLANK
N
C
u
ya
macaSt
Carlton Oaks Dr
Town Center Pkwy
Mandeville Rd
Willowgrove Pl
Cobblestone Pl
Willowbrook Way
Brookstone Pl
Wintercreek Pl
Parkside Pl
Whi
s
pering Willow Dr
River Park Dr
River Rock Ct
Brookview Ct
River Trail Pl
Willowgrove Ave
Silvercreek Dr
CLOW
CLOW
CSS
CSS
CSS
CSS
CSSB
CSSB

CSSB CSSB
CSSB
CSSB
CSSB
DEV
DEV
DEV
DH
DH
DH
DH
DH
DH
DH
DH
DH
DH
EUC
EW
FWM
FWM
FWM
FWM
NNG
NNR
OW
OW
SCWRF
SCWRF
SCWRF
SWS
SWS

SWS SWS
SWS
OW OW
Date: 4/28/2026 User: cgardner Path: Z:\Projects\j1861101\MAPDOC\San Diego River Fire Hazard Mitigation Plan EIR\San Diego River Fire Hazard Mitigation Plan EIR.aprx Map: Figure 4.1 Biological Resources Layout: Figure 4.1-1 Biological Resources 0 150 300
n
Feet
Project Boundary
Invasive Plant Species Proposed for Removal
Potential Invasive Species/Dead and Dying Tree
Removal Areas
Arundo donax (giant reed)
Special-Status Plant Species
Iva hayesiana (San Diego marsh-elder)
Vegetation Communities and Land Covers
Sensitive Riparian Vegetation Communities
Sensitive Upland Vegetation Communities
CLOW, Coast Live Oak Woodland
CSS, Diegan Coastal Sage Scrub
CSSB, Diegan Coastal Sage Scrub: Baccharisdominated
DEV, Urban/Developed
DH, Disturbed Habitat
EUC, Eucalyptus Woodland
EW, Emergent Wetland
FWM, Coastal and Valley Freshwater Marsh
NNG, Non-Native Grassland
NNR, Non-Native Riparian
OW, Open Water
SCWRF, Southern Cottonwood-Willow Riparian Forest
SWS, Southern Willow Scrub A
B
C
D
E
SOURCE: Vantor 2025; Open Street Map 2025
San Diego River Fire Hazard Mitigation Program EIR
Biological Resources
FIGURE 4.1-1B

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-6

INTENTIONALLY LEFT BLANK
N Magnolia Ave
Town Center Pkwy
Civic Center Rd
Eve Way Eve Ln
Leila Ln
Jim Ln
Park Center Dr
Cottonwood Ave
River
Park
Dr
Riverview Pkwy
Claudia Ave
C
h
u
bb L
a
n
e / Co
tton
wood
Av
e
CLOW
CLOW
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSSB
CSSB
CSSB

CSSB CSSB
CSSB
CSSB
CSSB
CSSB
CSSB
CSSB
DEV
DEV
DEV
DH
DH
DH
DH
DH
DH
DH
DH
DH
EUC
EUC
EUC
EW
EW
FWM
FWM

FWM FWM
FWM
FWM

FWM FWM
FWM
FWM
FWM
FWM
NNG
NNG
NNG
NNG
NNG

SCWRF SCWRF
SCWRF
SCWRF
SCWRF
SCWRF
SWRF
TS
TS
TS
TS
TS
TS
OW
Date: 4/28/2026 User: cgardner Path: Z:\Projects\j1861101\MAPDOC\San Diego River Fire Hazard Mitigation Plan EIR\San Diego River Fire Hazard Mitigation Plan EIR.aprx Map: Figure 4.1 Biological Resources Layout: Figure 4.1-1 Biological Resources 0 150 300
n
Feet
Project Boundary
Invasive Plant Species Proposed for Removal
Potential Invasive Species/Dead and Dying Tree
Removal Areas
Arundo donax (giant reed)
Vegetation Communities and Land Covers
Sensitive Riparian Vegetation Communities
Sensitive Upland Vegetation Communities
CLOW, Coast Live Oak Woodland
CSS, Diegan Coastal Sage Scrub
CSSB, Diegan Coastal Sage Scrub: Baccharisdominated
DEV, Urban/Developed
DH, Disturbed Habitat
EUC, Eucalyptus Woodland
EW, Emergent Wetland
FWM, Coastal and Valley Freshwater Marsh
NNG, Non-Native Grassland
OW, Open Water
SCWRF, Southern Cottonwood-Willow Riparian Forest
SWRF, Southern Arroyo Willow Riparian Forest
TS, Tamarisk Scrub
A
B
C
D
E
SOURCE: Vantor 2025; Open Street Map 2025
San Diego River Fire Hazard Mitigation Program EIR
Biological Resources
FIGURE 4.1-1C

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-8

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N Magnolia Ave
Woodside Ave
N Woodside Ave
Share Ct
Hil cl re
e
k
Way
Ra
msgate
Way
Chubb
Ln
H
ill
c
reek
Ln
Mavin Dr
Wheatlands Ct
Jeremy St
Stevens
Rd
Wheatlands Rd
Hartley Rd
Bundy Dr
Hinton Dr
Amster Dr
Abraham Way
Hillcreek Rd
Wheatlands Ave
Ä67
CLOW
CLOW
CSS
CSS
CSS
CSS
CSS
CSS
CSS

CSS CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
DEV
DEV
DEV
DEV

DEV DEV
DH
DH
DH
DH
DH
DH
FWM

FWM FWM
FWM
FWM
FWM

FWM FWM FWM
FWM
FWM
FWM
NNW
OW
OW
OW
OW
OW
SCWRF
SCWRF
SCWRF
SCWRF

SCWRF SCWRF
SCWRF

SRS SCWRF
SRS
SRS
SRS
SRS
SWRF
SWRF
SWRF
SWS
SWS
SWS
SWS
SWS

SWS SWS
SWS
Date: 4/28/2026 User: cgardner Path: Z:\Projects\j1861101\MAPDOC\San Diego River Fire Hazard Mitigation Plan EIR\San Diego River Fire Hazard Mitigation Plan EIR.aprx Map: Figure 4.1 Biological Resources Layout: Figure 4.1-1 Biological Resources 0 150 300
n
Feet
Project Boundary
Invasive Plant Species Proposed for Removal
Potential Invasive Species/Dead and Dying Tree
Removal Areas
Arundo donax (giant reed)
Special-Status Plant Species
Iva hayesiana (San Diego marsh-elder)
Vegetation Communities and Land Covers
Sensitive Riparian Vegetation Communities
Sensitive Upland Vegetation Communities
CLOW, Coast Live Oak Woodland
CSS, Diegan Coastal Sage Scrub
DEV, Urban/Developed
DH, Disturbed Habitat
FWM, Coastal and Valley Freshwater Marsh
NNW, Non-Native Woodland
OW, Open Water
SCWRF, Southern Cottonwood-Willow Riparian Forest
SRS, Southern Riparian Scrub
SWRF, Southern Arroyo Willow Riparian Forest
SWS, Southern Willow Scrub
A
B
C
D
E
SOURCE: Vantor 2025; Open Street Map 2025
San Diego River Fire Hazard Mitigation Program EIR
Biological Resources
FIGURE 4.1-1D

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-10

INTENTIONALLY LEFT BLANK
Woodside Ave
Riverford Rd
N Woodside Ave
Calle R Tuttle
Mission Park Pl
Security Way
Los Sanderos Dr
Woodside Ter
Karerllyn Dr
Ä67
CLOW
CLOWO
CLOWO
CSS
CSS
CSS
CSS

CSS CSS
CSS
CSS
CSS
CSS
CSSB
DEV
DEV
DH
DH
DH
FWM
FWM
FWM
FWM
FWM
FWM
FWM
NNR
NNW
NNW
NNW
OW
OW
SCWRF

SCWRF SCWRF
SCWRF
SCWRF
SCWRF
SCWRF
SWRF
SWRF
SWRF
SWS
SWS
SWS
SWS
Date: 4/28/2026 User: cgardner Path: Z:\Projects\j1861101\MAPDOC\San Diego River Fire Hazard Mitigation Plan EIR\San Diego River Fire Hazard Mitigation Plan EIR.aprx Map: Figure 4.1 Biological Resources Layout: Figure 4.1-1 Biological Resources 0 150 300
n
Feet
Project Boundary
Invasive Plant Species Proposed for Removal
Potential Invasive Species/Dead and Dying Tree
Removal Areas
Arundo donax (giant reed)
Vegetation Communities and Land Covers
Sensitive Riparian Vegetation Communities
Sensitive Upland Vegetation Communities
CLOW, Coast Live Oak Woodland
CLOWO, Open Coast Live Oak Woodland
CSS, Diegan Coastal Sage Scrub
CSSB, Diegan Coastal Sage Scrub: Baccharisdominated
DEV, Urban/Developed
DH, Disturbed Habitat
FWM, Coastal and Valley Freshwater Marsh
NNR, Non-Native Riparian
NNW, Non-Native Woodland
OW, Open Water
SCWRF, Southern Cottonwood-Willow Riparian Forest
SWRF, Southern Arroyo Willow Riparian Forest
SWS, Southern Willow Scrub
A
B
C
D
E
SOURCE: Vantor 2025; Open Street Map 2025
San Diego River Fire Hazard Mitigation Program EIR
Biological Resources
FIGURE 4.1-1E

4.1 – BIOLOGICAL RESOURCES
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INTENTIONALLY LEFT BLANK

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-13

4.1.1.2 Plants and Wildlife Observed
A total of 83 species of native or non-native plants, 52 (63%) native and 31 (37%) non-native, were detected within the Project Site during the biological reconnaissance surveys. Note that the biological reconnaissance was conducted during the fall, and many spring and summer-blooming plants may not have been detectible or identifiable yet. As such, plant diversity and abundance are likely underrepresented.

A total of 44 wildlife species consisting of 41 native and 3 non-native birds were detected within the Project Site during the biological reconnaissance surveys. Wildlife diversity was moderate during the biological reconnaissance surveys due to the presence of multiple native riparian and upland vegetation communities. However, nocturnal species, cryptic species, and fossorial species are likely underrepresented.

4.1.1.3 Special-Status Plants
Special-status plant species include those listed, or candidates for listing, as threatened or endangered by the U.S.

Fish and Wildlife Service (USFWS) and California Department of Fish and Wildlife (CDFW), and species identified as rare by the California Native Plant Society (particularly California Rare Plant Rank [CRPR] 1A, presumed extinct in California; CRPR 1B, rare, threatened, or endangered throughout its range; and CRPR 2, rare or endangered in California, more common elsewhere). Plant species covered under the City of Santee Draft Multiple Species Conservation Program (MSCP) Subarea Plan (City of Santee 2025) are also considered special-status. Appendix C of the Biological Resources Letter Report provides a table of all special-status plant species whose geographic ranges fall within the general vicinity of the Project Site.

A total of 32 plant species meet the special-status definition and have recorded occurrences in the Project vicinity.

The Project Site is not within any designated critical habitat for special-status plant species (USFWS 2025b). Of the 32 special-status plants known to occur in the region, one species was observed present within the Project Site during field surveys: San Diego marsh-elder (Iva hayesiana; CRPR 2B.2). San Diego marsh-elder populations were incidentally observed on the Project Site during the biological reconnaissance surveys within freshwater marsh habitat. Known locations of white rabbit-tobacco (Pseudognaphalium leucocephalum; CRPR 2B.2) that are present immediately outside of the Project Site boundary are shown on Figures 4.1-2A through 4.1-2E, Suitable SpecialStatus Plant Habitats, as well as the observed San Diego marsh-elder individuals. A total of 7 of the 32 specialstatus plant species were determined to have a moderate to high potential to occur in the native vegetation communities on the Project Site. Figures 4.1-2A through 4.1-2E depict the habitats that can support the seven special-status plants that were determined to have a moderate to high potential to occur. A total of 9 of the 32 special-status plants were determined to have a low potential to occur due to suitable elevation ranges but limited habitat suitability or lack of recent or nearby occurrence records; 15 of the 32 special-status plants are not expected to occur on the Project Site due to lack of suitable habitat, soils, and/or elevation range requirements. The remaining special-status plant species that are not expected to occur or were determined to have a low potential to occur on the Project Site due to lack of suitable habitat, elevation range, and/or soils. Table 4.1-2 summarizes the special-status plant species deemed present or with a moderate or high potential to occur on the Project Site.

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-14
Table 4.1-2. Special-Status Plant Species Present or with a Moderate to High Potential to Occur on the Project Site Scientific Name
Common
Name
Status*
(Federal/State/CRPR
/Santee MSCP)
Primary Habitat
Associations/Life Form/
Blooming Period/
Elevation Range (feet) Potential to Occur
Ambrosia pumila San Diego
ambrosia
FE/None/1B.1/None Chaparral, Coastal scrub,
valley and foothill grassland,
Vernal pools; alkaline
(sometimes), clay
(sometimes), disturbed
areas (often), loam
(sometimes), sandy
(sometimes)/perennial
rhizomatous herb/Apr–
Oct/65–1,360
Moderate potential to occur. The Project
Site is within the species known elevation
range; coastal scrub, non-native
grassland, and suitable substrates are
present. CNDDB occurrence records from
2006 overlap the Project Site (CDFW
2025). However, this species prefers
vernal pools and none were detected on
the Project Site during the biological
reconnaissance.

Centromadia pungens ssp.
laevis
smooth tarplant None/None/1B.1/
None
Chenopod scrub, meadows
and seeps, playas, riparian
woodland, valley and foothill
grassland; alkaline/annual
herb/Apr–Sep/0–2,100
Moderate potential to occur. The Project
Site is within the species known elevation
range; riparian woodland and non-native
grassland are present, but the Project
Site lacks alkaline soils. CNDDB
occurrence records from 2008–2017
located 1 mile from the Project Site
(CDFW 2025).

Isocoma menziesii var.
decumbens
decumbent
goldenbush
None/None/1B.2/
None
Chaparral, coastal scrub
(often disturbed areas,
sandy)/perennial shrub/
Apr–Nov/35–820
Moderate potential to occur. The Project
Site is within the species known elevation
range; coastal scrub with sandy soils and
disturbed areas are present. Multiple
CNDDB occurrence records from 2005
and 2019 located 2 miles from the
Project Site (CDFW 2025).

Iva hayesiana San Diego
marsh-elder
None/None/2B.2/
None
Marshes and swamps,
playas/perennial herb/
Apr–Oct/0–1,640
Present. Observed during the biological
reconnaissance surveys within the
freshwater marsh habitat on the Project
Site.

Monardella viminea willowy
monardella
FE/SE/1B.1/Covered Chaparral, Coastal scrub,
Riparian forest, Riparian
scrub, Riparian woodland;
Moderate to occur. The Project Site is
within the species known elevation range
and suitable modeled habitat occurs

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-15
Table 4.1-2. Special-Status Plant Species Present or with a Moderate to High Potential to Occur on the Project Site Scientific Name
Common
Name
Status*
(Federal/State/CRPR
/Santee MSCP)
Primary Habitat
Associations/Life Form/
Blooming Period/
Elevation Range (feet) Potential to Occur
Alluvial Terraces,
Washes/perennial
herb/June–Aug/165–740
within the Project Site (City of Santee
2025); however, this perennial species
was not observed during field surveys
and the site does not contain suitable
alluvial terraces. Closest CNDDB
occurrence record from 2007 is located
1 mile from the Project Site (CDFW
2025).

Pseudognaphalium
leucocephalum
white rabbittobaccoNone/None/2B.2/
None
Chaparral, cismontane
woodland, coastal scrub,
riparian woodland; gravelly,
sandy/perennial herb/(July)
Aug–Nov (Dec)/0–6,890
High potential to occur. Although not
detected during the biological
reconnaissance surveys, Dudek
biologists have documented this species
along sandy areas immediately adjacent
to the San Diego River while working on
other projects. The Project Site is within
the species known elevation range;
riparian woodland and sandy soils are
present. Consortium of California
Herbaria occurrence records from 2011
are located immediately outside of the
southern Project Site boundary (CCH
2025).

Quercus dumosa Nuttall’s scrub
oak
None/None/1B.1/
None
Chaparral, closed-cone
coniferous forest, coastal
scrub; clay, loam,
sandy/perennial evergreen
shrub/Feb–Apr (May–Aug)/
50–1,310
High potential to occur. The Project Site
is within the species known elevation
range; coastal scrub and suitable soils
present; may occur within coast live oak
woodland on the Project Site. CNDDB
occurrence records from 2009 overlap
the Project Site (CDFW 2025).

Stylocline citroleum oil neststraw None/None/1B.1/
None
Chenopod scrub, coastal
scrub, valley and foothill
Moderate potential to occur. The Project
Site is within the species known elevation
range; coastal scrub and non-native

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-16
Table 4.1-2. Special-Status Plant Species Present or with a Moderate to High Potential to Occur on the Project Site Scientific Name
Common
Name
Status*
(Federal/State/CRPR
/Santee MSCP)
Primary Habitat
Associations/Life Form/
Blooming Period/
Elevation Range (feet) Potential to Occur
grassland; clay/annual
herb/Mar–Apr/165–1,310
grassland are present along with clay
soils. Historic CNDDB occurrence records
from 1883 are 5 miles from the Project
Site and presumed extant (CDFW 2025).

Note: CNDDB = California Natural Diversity Database; CCH = Consortium of California Herbaria. * Status Legend:

Federal
FE: Federally listed as endangered
State
SE: State listed as endangered
CRPR: California Rare Plant Rank
1B: Plants rare, threatened, or endangered in California and elsewhere 2B: Plants rare, threatened, or endangered in California but more common elsewhere Threat Rank
.1 Seriously threatened in California (over 80% of occurrences threatened / high degree and immediacy of threat) .2 Moderately threatened in California (20% to 80% occurrences threatened/moderate degree and immediacy of threat) Other Designations
MSCP: Multiple Species Conservation Program (City of Santee Draft MSCP Subarea Plan).

Mission Gorge Rd
Fanita Dr
Carlton Hills Blvd
Ä125
DW
CLOW
CLOW
CLOW
CSS
CSS

CSS CSS
CSS
CSS
CSSB
CSSB
CSSB
CSSB
CSSB
DEV
DEV
DEV
DEV
DH
DH
DH DH
DH
DH
DH DH
DH
DH
DH
DH
DH
EUC
EUC
EUC
EUC
EW
EW
EW
EW
EW
FWM
FWM
FWM
FWM
FWM

FWM FWM
FWM
MFS
MFS
MFS
NNR
NNW
NNW
NVC
NVC
OW
SCWRF
SCWRF
SCWRF
SCWRF
SCWRF
SCWRF
SWS
SWS
SWS
SWS
SWS
SWS
SWS
Date: 4/28/2026 User: cgardner Path: Z:\Projects\j1861101\MAPDOC\San Diego River Fire Hazard Mitigation Plan EIR\San Diego River Fire Hazard Mitigation Plan EIR.aprx Map: Figure 4.1 Suitable Special-Status Plant Habitats Layout: Figure 4.1-2 Suitable Special-Status Plant Habitats 0 150 300
n
Feet
Project Boundary
Suitable Special-status Plant Habitat
Special-status Plants
Iva hayesiana (San Diego marsh-elder)
Vegetation Communities and Land Covers
CLOW, Coast Live Oak Woodland
CSS, Diegan Coastal Sage Scrub
CSSB, Diegan Coastal Sage Scrub: Baccharisdominated
DEV, Urban/Developed
DH, Disturbed Habitat
DW, Disturbed Wetland
EUC, Eucalyptus Woodland
EW, Emergent Wetland
FWM, Coastal and Valley Freshwater Marsh
MFS, Mule Fat Scrub
NNR, Non-Native Riparian
NNW, Non-Native Woodland
NVC, Non-Vegetated Channel or Floodway
OW, Open Water
SCWRF, Southern Cottonwood-Willow Riparian Forest
SWS, Southern Willow Scrub
A
B
C
D
E
SOURCE: Vantor 2025; Open Street Map 2025
San Diego River Fire Hazard Mitigation Program EIR
Suitable Special-Status Plant Habitats
FIGURE 4.1-2A

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-18

INTENTIONALLY LEFT BLANK
N
C
u
ya
macaSt
CLOW
CLOW
CSS
CSS
CSS
CSS
CSSB
CSSB

CSSB CSSB
CSSB
CSSB
CSSB
DEV
DEV
DEV
DH
DH
DH
DH
DH
DH
DH
DH
DH
DH
EUC
EW
FWM
FWM
FWM
FWM
NNG
NNR
OW
OW
SCWRF
SCWRF
SCWRF
SWS
SWS

SWS SWS
SWS
OW OW
Date: 4/28/2026 User: cgardner Path: Z:\Projects\j1861101\MAPDOC\San Diego River Fire Hazard Mitigation Plan EIR\San Diego River Fire Hazard Mitigation Plan EIR.aprx Map: Figure 4.1 Suitable Special-Status Plant Habitats Layout: Figure 4.1-2 Suitable Special-Status Plant Habitats 0 150 300
n
Feet
Project Boundary
Suitable Special-status Plant Habitat
Special-status Plants
Iva hayesiana (San Diego marsh-elder)
Vegetation Communities and Land Covers
CLOW, Coast Live Oak Woodland
CSS, Diegan Coastal Sage Scrub
CSSB, Diegan Coastal Sage Scrub: Baccharisdominated
DEV, Urban/Developed
DH, Disturbed Habitat
EUC, Eucalyptus Woodland
EW, Emergent Wetland
FWM, Coastal and Valley Freshwater Marsh
NNG, Non-Native Grassland
NNR, Non-Native Riparian
OW, Open Water
SCWRF, Southern Cottonwood-Willow Riparian Forest
SWS, Southern Willow Scrub
A
B
C
D
E
SOURCE: Vantor 2025; Open Street Map 2025
San Diego River Fire Hazard Mitigation Program EIR
Suitable Special-Status Plant Habitats
FIGURE 4.1-2B

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-20

INTENTIONALLY LEFT BLANK
N Magnolia Ave
CLOW
CLOW
CSS
CSS

CSS CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSSB
CSSB
CSSB
CSSB
CSSB
CSSB
CSSB
CSSB
CSSB
CSSB
CSSB
DEV
DEV
DEV
DH
DH
DH
DH
DH
DH
DH
DH
DH
EUC
EUC
EUC
EW
EW
FWM
FWM
FWM
FWM
FWM
FWM
FWM
FWM
FWM
FWM
FWM
FWM
NNG
NNG
NNG
NNG
NNG
SCWRF

SCWRF SCWRF
SCWRF
SCWRF
SCWRF
SWRF
TS
TS
TS
TS
TS
TS
OW
Date: 4/28/2026 User: cgardner Path: Z:\Projects\j1861101\MAPDOC\San Diego River Fire Hazard Mitigation Plan EIR\San Diego River Fire Hazard Mitigation Plan EIR.aprx Map: Figure 4.1 Suitable Special-Status Plant Habitats Layout: Figure 4.1-2 Suitable Special-Status Plant Habitats 0 150 300
n
Feet
Project Boundary
Suitable Special-status Plant Habitat
White rabbit-tobacco (Pseudognaphalium
leucocephalum)
Vegetation Communities and Land Covers
CLOW, Coast Live Oak Woodland
CSS, Diegan Coastal Sage Scrub
CSSB, Diegan Coastal Sage Scrub: Baccharisdominated
DEV, Urban/Developed
DH, Disturbed Habitat
EUC, Eucalyptus Woodland
EW, Emergent Wetland
FWM, Coastal and Valley Freshwater Marsh
NNG, Non-Native Grassland
OW, Open Water
SCWRF, Southern Cottonwood-Willow Riparian Forest
SWRF, Southern Arroyo Willow Riparian Forest
TS, Tamarisk Scrub
A
B
C
D
E
SOURCE: Vantor 2025; Open Street Map 2025
San Diego River Fire Hazard Mitigation Program EIR
Suitable Special-Status Plant Habitats
FIGURE 4.1-2C

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-22

INTENTIONALLY LEFT BLANK
N Magn
olia Ave
Woodside Ave
Ä67
CLOW
CLOW
CSS
CSS
CSS
CSS
CSS
CSS
CSS

CSS CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
DEV
DEV
DEV
DEV

DEV DEV
DH
DH
DH
DH
DH
DH
FWM

FWM FWM
FWM
FWM
FWM

FWM FWM FWM
FWM
FWM
FWM
NNW
OW
OW
OW
OW
OW
SCWRF
SCWRF
SCWRF
SCWRF
SCWRF
SCWRF
SCWRF
SCWRF
SRS
SRS
SRS
SRS
SRS
SWRF
SWRF
SWRF
SWS
SWS
SWS
SWS
SWS

SWS SWS
SWS
Date: 4/28/2026 User: cgardner Path: Z:\Projects\j1861101\MAPDOC\San Diego River Fire Hazard Mitigation Plan EIR\San Diego River Fire Hazard Mitigation Plan EIR.aprx Map: Figure 4.1 Suitable Special-Status Plant Habitats Layout: Figure 4.1-2 Suitable Special-Status Plant Habitats 0 150 300
n
Feet
Project Boundary
Suitable Special-status Plant Habitat
Special-status Plants
Iva hayesiana (San Diego marsh-elder)
Vegetation Communities and Land Covers
CLOW, Coast Live Oak Woodland
CSS, Diegan Coastal Sage Scrub
DEV, Urban/Developed
DH, Disturbed Habitat
FWM, Coastal and Valley Freshwater Marsh
NNW, Non-Native Woodland
OW, Open Water
SCWRF, Southern Cottonwood-Willow Riparian Forest
SRS, Southern Riparian Scrub
SWRF, Southern Arroyo Willow Riparian Forest
SWS, Southern Willow Scrub
A
B
C
D
E
SOURCE: Vantor 2025; Open Street Map 2025
San Diego River Fire Hazard Mitigation Program EIR
Suitable Special-Status Plant Habitats
FIGURE 4.1-2D

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-24

INTENTIONALLY LEFT BLANK
Woodside Ave
Ä67
CLOW
CLOWO
CLOWO
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSSB
DEV
DEV
DH
DH
DH
FWM
FWM
FWM
FWM
FWM
FWM
FWM
NNR
NNW
NNW
NNW
OW
OW
SCWRF

SCWRF SCWRF
SCWRF
SCWRF
SCWRF
SCWRF
SWRF
SWRF
SWRF
SWS
SWS
SWS
SWS
Date: 4/28/2026 User: cgardner Path: Z:\Projects\j1861101\MAPDOC\San Diego River Fire Hazard Mitigation Plan EIR\San Diego River Fire Hazard Mitigation Plan EIR.aprx Map: Figure 4.1 Suitable Special-Status Plant Habitats Layout: Figure 4.1-2 Suitable Special-Status Plant Habitats 0 150 300
n
Feet
Project Boundary
Suitable Special-status Plant Habitat
Vegetation Communities and Land Covers
CLOW, Coast Live Oak Woodland
CLOWO, Open Coast Live Oak Woodland
CSS, Diegan Coastal Sage Scrub
CSSB, Diegan Coastal Sage Scrub: Baccharisdominated
DEV, Urban/Developed
DH, Disturbed Habitat
FWM, Coastal and Valley Freshwater Marsh
NNR, Non-Native Riparian
NNW, Non-Native Woodland
OW, Open Water
SCWRF, Southern Cottonwood-Willow Riparian Forest
SWRF, Southern Arroyo Willow Riparian Forest
SWS, Southern Willow Scrub
A
B
C
D
E
SOURCE: Vantor 2025; Open Street Map 2025
San Diego River Fire Hazard Mitigation Program EIR
Suitable Special-Status Plant Habitats
FIGURE 4.1-2E

4.1 – BIOLOGICAL RESOURCES
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4.1.1.4 Special-Status Wildlife
Special-status wildlife species include those listed, or candidates for listing, as threatened or endangered by USFWS and CDFW, those designated as Species of Special Concern by CDFW, those designated as sensitive by USFWS, and Covered Species under the City of Santee Draft MSCP Subarea Plan. Appendix D of the Biological Resources Letter Report provides a table of all special-status wildlife species whose geographic ranges fall within the general vicinity of the Project Site. Special-status species’ potential to occur within the Project Site were evaluated based on known species distribution, species-specific habitat preferences, and Dudek biologists’ knowledge of regional biological resources. Each special-status species was assigned a rating of “not expected,” “low,” “moderate,” or “high” potential to occur within the Project Site based on relative location to known occurrences, vegetation community, soil, and elevation.

Of the 41 special-status wildlife species known to occur in the region, a total of 24 species were determined to have a moderate to high potential to occur based on overlapping or nearby known occurrence records, as well as suitable habitats present. The remaining 17 special-status wildlife species that are not expected to occur or were determined to have a low potential to occur due to lack of suitable habitat. In addition, 2 of the 41 special-status wildlife are considered present on the Project Site: yellow warbler (Setophaga petechia) (CDFW Species of Special Concern when nesting) and least Bell’s vireo (Vireo bellii pusillus) (federally and state endangered). The western portion of the Project Site is within designated critical habitat for least Bell’s vireo as shown on Figure 4.1-3A, Suitable SpecialStatus Wildlife Habitats, and there are recent occurrence records that overlap the Project Site (USFWS 2025b; CDFW 2025). Multiple riparian woodlands, forests, scrubs, and emergent vegetation can support this species nesting and foraging on the Project Site. Yellow warbler is also considered present since the Project Site supports suitable nesting and foraging habitat and has been previously documented within the Project Site. Furthermore, coastal sage scrub habitats on the Project Site have a moderate potential to support the coastal California gnatcatcher (Polioptila californica californica) (federally threatened and CDFW Species of Special Concern) as there are recent occurrence records and designated critical habitat immediately adjacent to the Project Site (Figures 4.1-4, Wildlife Corridors and Habitat Linkages). Yellow warbler, least Bell’s vireo, and coastal California gnatcatcher are all Covered Species under the City of Santee Draft MSCP Subarea Plan. Figures 4.1-3A through

4.1-3E also depicts the suitable habitats for special-status wildlife present, considered present, or determined to have a moderate or high potential to occur on the Project Site. Table 4.1-3 summarizes the special-status wildlife deemed present, considered present, or with a moderate to high potential to occur on the Project Site.

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-28
Table 4.1-3. Special-Status Wildlife Present, Considered Present, or with a Moderate to High Potential to Occur on the Project Site
Scientific Name Common Name
Status*
(Federal/State/Draft
Santee MSCP) Habitat Potential to Occur
Reptiles
Anniella stebbinsi southern
California legless
lizard
None/SSC/None Coastal dunes, stabilized dunes,
beaches, dry washes, valley–
foothill, chaparral, and scrubs;
pine, oak, and riparian
woodlands; associated with
sparse vegetation and moist
sandy or loose, loamy soils
High potential to occur. Suitable habitats
present (coastal scrub, wash, oak
woodland, riparian woodland; moist sandy
soils). CNDDB occurrence record from
2012 overlap the western portion of the
Project Site (CDFW 2025).

Arizona elegans
occidentalis
California glossy
snake
None/SSC/None Arid scrub, rocky washes,
grasslands, chaparral, open areas
with loose soil
High potential to occur. Suitable substrate
present. Historic CNDDB occurrence
records from 1973 overlap the Project
Site (CDFW 2025).

Aspidoscelis
hyperythrabeldingi
Belding’s orangethroated whiptailNone/WL/Covered Low-elevation coastal scrub, chaparral, and valley–foothill
hardwood
High potential to occur. Suitable coastal
scrub habitat and hardwood present.

CNDDB occurrence records from 1999
border the northern Project Site boundary
(CDFW 2025).

Aspidoscelis tigris
stejnegeri
San Diegan tiger
whiptail
None/SSC/None Hot and dry areas with sparse
foliage, including chaparral,
woodland, and riparian areas
High potential to occur. Riparian
woodland is present. CNDDB occurrence
records from 2008 are located 4 miles
from the Project Site (CDFW 2025).

Crotalus ruber red diamondback rattlesnakeNone/SSC/None Coastal scrub, chaparral, oak and pine woodlands, rocky
grasslands, cultivated areas, and
desert flats
Moderate potential to occur. Coastal
scrub and oak woodland present could
provide suitable habitat for this species.

CNDDB occurrence record from 1998
within 1 mile of the Project Site (CDFW
2025).

Phrynosoma blainvillii Blainsville’s
horned lizard
None/SSC/Covered Open areas of sandy soil in
valleys, foothills, and semi-arid
mountains including coastal
Moderate potential to occur. Coastal
scrub, riparian woodland, and grassland
with sandy soils present. Historic CNDDB

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-29
Table 4.1-3. Special-Status Wildlife Present, Considered Present, or with a Moderate to High Potential to Occur on the Project Site
Scientific Name Common Name
Status*
(Federal/State/Draft
Santee MSCP) Habitat Potential to Occur
scrub, chaparral, valley–foothill
hardwood, conifer, riparian, pine–
cypress, juniper, and annual
grassland habitats
occurrence records from 1937 overlap
the Project Site; however, the Project Site
is currently fairly isolated (CDFW 2025).

Salvadora hexalepis
virgultea
coast patchnosed snakeFPT/SSC/None Brushy or shrubby vegetation; requires small mammal burrows
for refuge and overwintering sites
Moderate potential to occur. Suitable
brushy or shrubby vegetation present. A
CNDDB occurrence record from 2004 is
located 4 miles from the Project Site
(CDFW 2025).

Thamnophis
hammondii
two-striped
gartersnake
None/SSC/None Streams, creeks, pools, streams
with rocky beds, ponds, lakes,
vernal pools
High potential to occur. San Diego River
on site provides suitable habitat. A
CNDDB occurrence record from 1998 is
within 1 mile of the Project Site (CDFW
2025).

Birds
Athene cunicularia
(burrow sites and
some wintering sites)
burrowing owl BCC/SSC, SC/Covered Nests and forages in grassland, open scrub, and agriculture,
particularly with ground squirrel
burrows
Moderate potential to occur. Coastal
scrub and grassland present. The nearest
CNDDB occurrence record within 1 mile of
the Project Site is from 1921 and
extirpated; however, there are occurrence
records from 2024 located 2 miles from
the Project Site (CDFW 2025).

Coturnicops
noveboracensis
yellow rail BCC/SSC/None Nesting requires wet marsh/
sedge meadows or coastal
marshes with wet soil and
shallow, standing water
Moderate potential to occur. Suitable
nesting habitat present (freshwater
marsh, shallow standing water) along San
Diego River in the Project Site. CNDDB
occurrence records from 1998 overlap
the Project Site (CDFW 2025).

Icteria virens
(nesting)
yellow-breasted
chat
None/SSC/None Nests and forages in dense,
relatively wide riparian woodlands
Considered present. Suitable nesting and
foraging habitat present; San Diego River

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-30
Table 4.1-3. Special-Status Wildlife Present, Considered Present, or with a Moderate to High Potential to Occur on the Project Site
Scientific Name Common Name
Status*
(Federal/State/Draft
Santee MSCP) Habitat Potential to Occur
and thickets of willows, vine
tangles, and dense brush
supports relatively wide riparian thickets
of willows and dense brush throughout
the Project Site. CNDDB occurrence
record from 1994 are located 4 miles
from the Project Site (CDFW 2025).

Polioptila californica
californica
coastal California
gnatcatcher
FT/SSC/Covered Nests and forages in various sage
scrub communities, often
dominated by California
sagebrush and buckwheat;
generally avoids nesting in areas
with a slope of greater than 40%;
majority of nesting at less than
1,000 feet above mean sea level
Considered present. Coastal sage scrub is
present within uplands along the north
and south Project Site boundaries. There
are CNDDB occurrence records from
1999 border the north Project Site
boundary (CDFW 2025). There is
designated critical habitat for this species
approximately 1 mile north and south of
the Project Site (USFWS 2025b).

Setophaga petechia
(nesting)
yellow warbler None/SSC/None Nests and forages in riparian and oak woodlands, montane
chaparral, open ponderosa pine,
and mixed-conifer habitats
Considered present. Suitable nesting and
foraging habitat present throughout the
riparian areas along the San Diego River
in the Project Site. CNDDB occurrence
record from 1972 located 2 miles from
the Project Site (CDFW 2025). Although
not detected during the biological
reconnaissance surveys, Dudek biologists
have documented this species along the
San Diego River within Santee while
working on other projects.

Vireo bellii pusillus
(nesting)
least Bell’s vireo FE/SE/Covered Nests and forages in low, dense riparian thickets along water or
along dry parts of intermittent
streams; forages in riparian and
adjacent shrubland late in nesting
season
Considered present. Suitable nesting and
foraging habitat present (riparian
woodlands, mulefat scrub, willow scrub)
along San Diego River. CNDDB
occurrence records from 2012 overlap
the Project Site (CDFW 2025). The

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-31
Table 4.1-3. Special-Status Wildlife Present, Considered Present, or with a Moderate to High Potential to Occur on the Project Site
Scientific Name Common Name
Status*
(Federal/State/Draft
Santee MSCP) Habitat Potential to Occur
western portion of the Project Site
overlaps designated critical habitat for
this species (USFWS 2025b). Although
not detected during the biological
reconnaissance surveys, Dudek biologists
have documented this species along the
San Diego River within Santee while
working on other projects.

Botaurus exilis
(nesting)
least bittern None/SSC/None Nests in freshwater and brackish marshes with dense, tall growth
of aquatic and semi-aquatic
vegetation
Moderate potential to occur. Suitable
nesting habitat present. CNDDB
occurrence record from 2007 located 2
miles from the Project Site (CDFW 2025).

Mammals
Antrozous pallidus pallid bat None/SSC/
None
Grasslands, shrublands,
woodlands, forests; most
common in open, dry habitats
with rocky outcrops for roosting,
but also roosts in built structures
and trees
Moderate potential to occur. Suitable
habitat (grassland, woodlands, riparian
forest) is present although the site lacks
rocky outcrops for roosting; there are
CNDDB occurrence records from 1951 that
overlap the Project Site (CDFW 2025).

Corynorhinus
townsendii
Townsend’s bigeared batNone/SSC/
None
Mesic habitats characterized by
coniferous and deciduous forests
and riparian habitat, but also
xeric areas; roosts in limestone
caves and lava tubes, built
structures, and tunnels
Moderate potential to occur. No roosting
habitat present but may forage over San
Diego River’s riparian habitats throughout
the Project Site. CNDDB occurrence
record from 1991 located 5 miles from
the Project Site (CDFW 2025).

Dasypterus xanthinus western yellow
bat
None/SSC/None Valley–foothill riparian, desert
riparian, desert wash, and palm
oasis habitats; below 2,000 feet
above mean sea level; roosts in
riparian and palms
High potential to occur. Suitable roosting
habitat (riparian) present. CNDDB
occurrence records from 1979 are
immediately east of the Project Site
(CDFW 2025).

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-32
Table 4.1-3. Special-Status Wildlife Present, Considered Present, or with a Moderate to High Potential to Occur on the Project Site
Scientific Name Common Name
Status*
(Federal/State/Draft
Santee MSCP) Habitat Potential to Occur
Eumops perotis
californicus
western mastiff
bat
None/SSC/None Chaparral, coastal and desert
scrub, coniferous and deciduous
forest and woodland; roosts in
crevices in rocky canyons and cliffs
where the canyon or cliff is vertical
or nearly vertical, trees, and tunnels
Moderate potential to occur. Coastal
scrub and woodlands present could
provide roosting habitat. CNDDB
occurrence records from 2003 located 4
miles from the Project Site (CDFW 2025).

Neotoma lepida
intermedia
San Diego desert
woodrat
None/SSC/None Coastal scrub, desert scrub,
chaparral, cacti, rocky areas
Moderate potential to occur in coastal
scrub throughout the Project Site,
although rocky areas are absent. CNDDB
occurrence record from 1998 within 1
mile of the Project Site (CDFW 2025).

Nyctinomops
femorosaccus
pocketed freetailed batNone/SSC/None Pinyon–juniper woodlands, desert scrub, desert succulent shrub,
desert riparian, desert wash,
alkali desert scrub, Joshua tree,
and palm oases; roosts in high
cliffs or rock outcrops with dropoffs, caverns, and buildings Moderate potential to occur. No roosting
habitat present; however, CNDDB
occurrence records from 1990 overlap
the Project Site and there is
riparian/wash habitat along the Project
Site that can be seasonally arid. Multiple
CNDDB occurrence records from 1983 to
2003 located 3 to 5 miles from the
Project Site (CDFW 2025).

Nyctinomops
macrotis
Big free-tailed bat None/SSC/None Rocky areas; roosts in caves, holes in trees, buildings, and
crevices on cliffs and rocky
outcrops; forages over water
High potential to occur. May forage over
San Diego River in the Project Site. Not
expected to roost as no suitable roosting
habitat present. CNDDB occurrence
records from 1989 overlap the Project
Site (CDFW 2025).

Lasiurus frantzii western red bat None/SSC/None Forest, woodland, riparian, mesquite bosque, and orchards,
including fig, apricot, peach, pear,
almond, walnut, and orange;
roosts in tree canopy
Moderate potential to occur. Suitable
roosting habitat present (riparian forest
and woodland). A CNDDB occurrence
record from 2003 is located 4 miles from
the Project Site (CDFW 2025).

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-33
Table 4.1-3. Special-Status Wildlife Present, Considered Present, or with a Moderate to High Potential to Occur on the Project Site
Scientific Name Common Name
Status*
(Federal/State/Draft
Santee MSCP) Habitat Potential to Occur
Invertebrates
Bombus crotchii Crotch’s bumble
bee
None/SCE/
Covered
Open grassland and scrub
communities supporting suitable
floral resources.

Moderate potential to occur. Suitable
habitat present along with floral
resources for foraging. Nearest CNDDB
occurrence record is 2 miles from the
Project Site, from 2020 (CDFW 2025).

Note: CNDDB = California Natural Diversity Database.
* Status Abbreviations:

Federal
FE: Federally listed as endangered
FT: Federally listed as threatened
FPT: Federally proposed for listing as threatened
BCC: U.S. Fish and Wildlife Service Bird of Conservation Concern State
SSC: California Species of Special Concern
WL: California Watch List Species
SE: State listed as endangered
SC: State candidate for listing as threatened or endangered SCE: State candidate for listing as endangered
Other Designations
MSCP: Multiple Species Conservation Program (City of Santee Draft MSCP Subarea Plan)

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-34

4.1.1.5 Jurisdictional Resources
Although a formal jurisdictional delineation was not conducted during the biological reconnaissance field surveys, the Project Site was evaluated for the potential to support jurisdictional waters regulated under the federal Clean Water Act (CWA), California Fish and Game Code, and Porter–Cologne Water Quality Act (Porter–Cologne Act).

Baseline wetland mapping from the USFWS National Wetlands Inventory and U.S. Geological Survey National Hydrography Dataset were used as a basis to inform the outer limits of potentially jurisdictional waters, such as streams or wetlands, on the Project Site (USFWS 2025a; USGS 2025).

Potential non-wetland waters of the United States and state regulated by the U.S. Army Corps of Engineers (USACE) and/or Regional Water Quality Control Board (RWQCB) and CDFW streambed/associated riparian habitat were identified in the Project Site, consisting of the San Diego River, its tributary (Forester Creek), and multiple associated riparian/wetland vegetation communities/land covers. These features were informally mapped and examined based on the observable presence of an ordinary high water mark, hydrology indicators and/or hydrophytic (wetland) vegetation. No formal wetland determination points were taken in the Project Site.

Potential jurisdictional aquatic resources on the Project Site are depicted on Figure 4.1-5, Potentially Jurisdictional Aquatic Resources. Table 4.1-4 summarizes the acreages of the riparian/wetland vegetation communities (all considered sensitive by the City of Santee MSCP Draft Subarea Plan) and National Wetlands Inventory-mapped wetlands on the Project Site that would be considered potential jurisdictional aquatic resources. Note that the acreage of jurisdictional aquatic resources on the Project Site was calculated based off the riparian/wetland vegetation communities mapping conducted during the biological reconnaissance surveys; any National Wetlands Inventory-mapped resources that did not overlap the vegetation communities were added to the overall potential jurisdictional resources acreage to conservatively estimate the extent of potentially jurisdictional resources on the Project Site.

Table 4.1-4. Potential Jurisdictional Aquatic Resources Within the Project Site Aquatic Resource Type Acreage

USACE/RWQCB/CDFW
Non-wetland Waters/Streambeds 40.18
Wetlands/Riparian Habitat 195.47
Potential Jurisdictional Aquatic Resource Total 236.65
Source: USFWS National Wetlands Inventory (USFWS 2025a).

Notes: USACE = U.S. Army Corps of Engineers; RWQCB = Regional Water Quality Control Board; CDFW = California Department of Fish and Wildlife.
"J
"J
!P
!P
!P
!P
#
0#
0 0#
0#
0#
0#
0#
0#
0#
0#
0#
0#
0#
0#
0#
Mission Gorge Rd
Fanita Dr
Carlton Hills Blvd
Ä125
DW
CLOW
CLOW
CLOW
CSS
CSS

CSS CSS
CSS
CSS
CSSB
CSSB
CSSB
CSSB
CSSB
DEV
DEV
DEV
DEV
DH
DH
DH DH
DH
DH
DH DH
DH
DH
DH
DH
DH
EUC
EUC
EUC
EUC
EW
EW
EW
EW
EW
FWM
FWM
FWM
FWM
FWM

FWM FWM
FWM
MFS
MFS
MFS
NNR
NNW
NNW
NVC
NVC
OW
SCWRF
SCWRF
SCWRF
SCWRF
SCWRF
SCWRF
SWS
SWS
SWS
SWS
SWS
SWS
SWS
Date: 4/28/2026 User: cgardner Path: Z:\Projects\j1861101\MAPDOC\San Diego River Fire Hazard Mitigation Plan EIR\San Diego River Fire Hazard Mitigation Plan EIR.aprx Map: Figure 4.1 Suitable Special-Status Wildlife Habitats Layout: Figure 4.1-3 Suitable Special-Status Wildlife Habitats 0 150 300
n
Feet
Project Boundary
Suitable Special-status Wildlife Habitat
Sensitive Species
"J Yellow warbler
!P Yellow-breasted chat
0# least Bell's vireo
USFWS Critical Habitat
Least Bell's vireo
Vegetation Communities and Land Covers
CLOW, Coast Live Oak Woodland
CLOWO, Open Coast Live Oak Woodland
CSS, Diegan Coastal Sage Scrub
CSSB, Diegan Coastal Sage Scrub: Baccharis-dominated
DEV, Urban/Developed
DH, Disturbed Habitat
DW, Disturbed Wetland
EUC, Eucalyptus Woodland
EW, Emergent Wetland
FWM, Coastal and Valley Freshwater Marsh
MFS, Mule Fat Scrub
NNG, Non-Native Grassland
NNR, Non-Native Riparian
NNW, Non-Native Woodland
NVC, Non-Vegetated Channel or Floodway
OW, Open Water
SCWRF, Southern Cottonwood-Willow Riparian Forest
SRS, Southern Riparian Scrub
SWRF, Southern Arroyo Willow Riparian Forest
SWS, Southern Willow Scrub
TS, Tamarisk Scrub
A
B
C
D
E
SOURCE: Vantor 2025; Open Street Map 2025
San Diego River Fire Hazard Mitigation Program EIR
Suitable Special-Status Wildlife Habitats
FIGURE 4.1-3A

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-36

INTENTIONALLY LEFT BLANK
N
C
u
ya
macaSt
CLOW
CLOW
CSS
CSS
CSS
CSS
CSSB
CSSB

CSSB CSSB
CSSB
CSSB
CSSB
DEV
DEV
DEV
DH
DH
DH
DH
DH
DH
DH
DH
DH
DH
EUC
EW
FWM
FWM
FWM
FWM
NNG
NNR
OW
OW
SCWRF
SCWRF
SCWRF
SWS
SWS

SWS SWS
SWS
OW OW
Date: 4/28/2026 User: cgardner Path: Z:\Projects\j1861101\MAPDOC\San Diego River Fire Hazard Mitigation Plan EIR\San Diego River Fire Hazard Mitigation Plan EIR.aprx Map: Figure 4.1 Suitable Special-Status Wildlife Habitats Layout: Figure 4.1-3 Suitable Special-Status Wildlife Habitats 0 150 300
n
Feet
Project Boundary
Suitable Special-status Wildlife Habitat
Vegetation Communities and Land Covers
CLOW, Coast Live Oak Woodland
CLOWO, Open Coast Live Oak Woodland
CSS, Diegan Coastal Sage Scrub
CSSB, Diegan Coastal Sage Scrub: Baccharis-dominated
DEV, Urban/Developed
DH, Disturbed Habitat
DW, Disturbed Wetland
EUC, Eucalyptus Woodland
EW, Emergent Wetland
FWM, Coastal and Valley Freshwater Marsh
MFS, Mule Fat Scrub
NNG, Non-Native Grassland
NNR, Non-Native Riparian
NNW, Non-Native Woodland
NVC, Non-Vegetated Channel or Floodway
OW, Open Water
SCWRF, Southern Cottonwood-Willow Riparian Forest
SRS, Southern Riparian Scrub
SWRF, Southern Arroyo Willow Riparian Forest
SWS, Southern Willow Scrub
TS, Tamarisk Scrub
A
B
C
D
E
SOURCE: Vantor 2025; Open Street Map 2025
San Diego River Fire Hazard Mitigation Program EIR
Suitable Special-Status Wildlife Habitats
FIGURE 4.1-3B

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-38

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"J
"J "J
"J
"J
0#
0#
0#
N Magnolia Ave
CLOW
CLOW
CSS
CSS

SCWRF SCWRF
SCWRF
SCWRF
SCWRF
SWRF
TS
TS
TS
TS
TS
TS
OW
Date: 4/28/2026 User: cgardner Path: Z:\Projects\j1861101\MAPDOC\San Diego River Fire Hazard Mitigation Plan EIR\San Diego River Fire Hazard Mitigation Plan EIR.aprx Map: Figure 4.1 Suitable Special-Status Wildlife Habitats Layout: Figure 4.1-3 Suitable Special-Status Wildlife Habitats 0 150 300
n
Feet
Project Boundary
Suitable Special-status Wildlife Habitat
Sensitive Species
"J Yellow warbler
0# least Bell's vireo
Vegetation Communities and Land Covers
CLOW, Coast Live Oak Woodland
CLOWO, Open Coast Live Oak Woodland
CSS, Diegan Coastal Sage Scrub
CSSB, Diegan Coastal Sage Scrub: Baccharis-dominated
DEV, Urban/Developed
DH, Disturbed Habitat
DW, Disturbed Wetland
EUC, Eucalyptus Woodland
EW, Emergent Wetland
FWM, Coastal and Valley Freshwater Marsh
MFS, Mule Fat Scrub
NNG, Non-Native Grassland
NNR, Non-Native Riparian
NNW, Non-Native Woodland
NVC, Non-Vegetated Channel or Floodway
OW, Open Water
SCWRF, Southern Cottonwood-Willow Riparian Forest
SRS, Southern Riparian Scrub
SWRF, Southern Arroyo Willow Riparian Forest
SWS, Southern Willow Scrub
TS, Tamarisk Scrub
A
B
C
D
E
SOURCE: Vantor 2025; Open Street Map 2025
San Diego River Fire Hazard Mitigation Program EIR
Suitable Special-Status Wildlife Habitats
FIGURE 4.1-3C

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-40

INTENTIONALLY LEFT BLANK
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"J
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!P
0#
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0#
0#
0#
0#
0#
0#
N Magn
olia Ave
Woodside Ave
Ä67
CLOW
CLOW
CSS
CSS
CSS
CSS
CSS
CSS
CSS

CSS CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
DEV
DEV
DEV
DEV

DEV DEV
DH
DH
DH
DH
DH
DH
FWM

FWM FWM
FWM
FWM
FWM

FWM FWM FWM
FWM
FWM
FWM
NNW
OW
OW
OW
OW
OW
SCWRF
SCWRF
SCWRF
SCWRF
SCWRF
SCWRF
SCWRF
SCWRF
SRS
SRS
SRS
SRS
SRS
SWRF
SWRF
SWRF
SWS
SWS
SWS
SWS
SWS

SWS SWS
SWS
Date: 4/28/2026 User: cgardner Path: Z:\Projects\j1861101\MAPDOC\San Diego River Fire Hazard Mitigation Plan EIR\San Diego River Fire Hazard Mitigation Plan EIR.aprx Map: Figure 4.1 Suitable Special-Status Wildlife Habitats Layout: Figure 4.1-3 Suitable Special-Status Wildlife Habitats 0 150 300
n
Feet
Project Boundary
Suitable Special-status Wildlife Habitat
Sensitive Species
"J Yellow warbler
!P Yellow-breasted chat
0# least Bell's vireo
Vegetation Communities and Land Covers
CLOW, Coast Live Oak Woodland
CLOWO, Open Coast Live Oak Woodland
CSS, Diegan Coastal Sage Scrub
CSSB, Diegan Coastal Sage Scrub: Baccharis-dominated
DEV, Urban/Developed
DH, Disturbed Habitat
DW, Disturbed Wetland
EUC, Eucalyptus Woodland
EW, Emergent Wetland
FWM, Coastal and Valley Freshwater Marsh
MFS, Mule Fat Scrub
NNG, Non-Native Grassland
NNR, Non-Native Riparian
NNW, Non-Native Woodland
NVC, Non-Vegetated Channel or Floodway
OW, Open Water
SCWRF, Southern Cottonwood-Willow Riparian Forest
SRS, Southern Riparian Scrub
SWRF, Southern Arroyo Willow Riparian Forest
SWS, Southern Willow Scrub
TS, Tamarisk Scrub
A
B
C
D
E
SOURCE: Vantor 2025; Open Street Map 2025
San Diego River Fire Hazard Mitigation Program EIR
Suitable Special-Status Wildlife Habitats
FIGURE 4.1-3D

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-42

INTENTIONALLY LEFT BLANK
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!P
"J
Woodside Ave
Ä67
CLOW
CLOWO
CLOWO
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSS
CSSB
DEV
DEV
DH
DH
DH
FWM
FWM
FWM
FWM
FWM
FWM
FWM
NNR
NNW
NNW
NNW
OW
OW
SCWRF

SCWRF SCWRF
SCWRF
SCWRF
SCWRF
SCWRF
SWRF
SWRF
SWRF
SWS
SWS
SWS
SWS
Date: 4/28/2026 User: cgardner Path: Z:\Projects\j1861101\MAPDOC\San Diego River Fire Hazard Mitigation Plan EIR\San Diego River Fire Hazard Mitigation Plan EIR.aprx Map: Figure 4.1 Suitable Special-Status Wildlife Habitats Layout: Figure 4.1-3 Suitable Special-Status Wildlife Habitats 0 150 300
n
Feet
Project Boundary
Suitable Special-status Wildlife Habitat
Sensitive Species
!P Yellow-breasted chat
"J coastal California gnatcatcher
Vegetation Communities and Land Covers
CLOW, Coast Live Oak Woodland
CLOWO, Open Coast Live Oak Woodland
CSS, Diegan Coastal Sage Scrub
CSSB, Diegan Coastal Sage Scrub: Baccharis-dominated
DEV, Urban/Developed
DH, Disturbed Habitat
DW, Disturbed Wetland
EUC, Eucalyptus Woodland
EW, Emergent Wetland
FWM, Coastal and Valley Freshwater Marsh
MFS, Mule Fat Scrub
NNG, Non-Native Grassland
NNR, Non-Native Riparian
NNW, Non-Native Woodland
NVC, Non-Vegetated Channel or Floodway
OW, Open Water
SCWRF, Southern Cottonwood-Willow Riparian Forest
SRS, Southern Riparian Scrub
SWRF, Southern Arroyo Willow Riparian Forest
SWS, Southern Willow Scrub
TS, Tamarisk Scrub
A
B
C
D
E
SOURCE: Vantor 2025; Open Street Map 2025
San Diego River Fire Hazard Mitigation Program EIR
Suitable Special-Status Wildlife Habitats
FIGURE 4.1-3E

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-44

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$
$
$
$
$
$
$$
Fa
nita D
r
Mission Gorge Rd
N
Magnolia Ave
Prospect Ave
Carlton
Hills
Blvd
N Cu
y
a
m
aca
St
Mast Blvd
Woodside Ave
Cuyamaca St Ä125
Ä67
Ä52
Project Boundary
$
$ coastal California gnatcatcher Stepping Stone Linkage coastal California gnatcatcher Habitat Blocks
Existing Protected Open Space
Hardline Conservation Lands
San Diego River Subunit (Draft Santee MSCP Subarea Plan (City of Santee 2025)) San Diego River Corridor Ordinance (Draft Santee MSCP Subarea Plan (City of Santee 2025)) Biological Core and Linkage Areas
Date: 4/16/2026 User: cgardner Path: Z:\Projects\j1861101\MAPDOC\San Diego River Fire Hazard Mitigation Plan EIR\San Diego River Fire Hazard Mitigation Plan EIR.aprx Map: Figure 4.1 Wildlife Corridors and Habitat Linkages Layout: Figure 4.1-4 Wildlife Corridors and Habitat Linkages 0 500 1,000
n
Feet
SOURCE: Vantor 2025; Open Street Map 2025; SanGIS 2025; City of Santee 2025 San Diego River Fire Hazard Mitigation Program EIR
Wildlife Corridors and Habitat Linkages
FIGURE 4.1-4

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-46

INTENTIONALLY LEFT BLANK
Fanita
D
r
Mission Gorge Rd
N
Magnolia Ave
Prospect Ave
Carlton
Hills
Blvd
N Cu
y
a
m
aca
St
Mast Blvd
Woodside Ave
Cuyamaca St Ä125
Ä67
Ä52
Project Boundary
Sensitive Riparian Vegetation Communities
National Wetlands Inventory
Freshwater Emergent Wetland
Freshwater Forested/Shrub Wetland
Freshwater Pond
Riverine
Date: 4/16/2026 User: cgardner Path: Z:\Projects\j1861101\MAPDOC\San Diego River Fire Hazard Mitigation Plan EIR\San Diego River Fire Hazard Mitigation Plan EIR.aprx Map: Figure 8 Potentially Jurisdictional Aquatic Resources Layout: Figure 4.1-5 Potentially Jurisdictional Aquatic Resources 0 500 1,000
n
Feet
SOURCE: Vantor 2025; Open Street Map 2025; USGS NHD 2025; USFWS NWI 2025 San Diego River Fire Hazard Mitigation Program EIR
Potentially Jurisdictional Aquatic Resources
FIGURE 4.1-5

4.1 – BIOLOGICAL RESOURCES
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4.1.1.6 Wildlife Corridors, Habitat Linkages, and Wildlife Nursery Sites The San Diego MSCP Plan (City of San Diego 1998) defines core and linkage areas as those maintaining ecosystem function and processes, including large animal movement. Each core area is connected to other core areas or to habitat areas outside of the MSCP study area either through common boundaries or through linkages. Core areas have multiple connections to help ensure that the balance in the ecosystem would be maintained.

Biological core and linkage areas are identified in the MSCP Plan (City of San Diego 1998) and used without revision on Figure 2-12 in the Draft Santee MSCP Subarea Plan (City of Santee 2025) and shown in context of the Project Site on Figure 4.1-6, MSCP Lands. According to the City of Santee Draft MSCP Subarea Plan, the San Diego River provides a corridor for wildlife movement and connectivity through the urbanized portion of the City of Santee (City of Santee 2025). The western portion of the Project Site from Forester Creek up to Mast Park is mapped as a San Diego County MSCP biological core and linkage area (Figure 2-12 in City of Santee 2025). The San Diego River segment within the Project Site is identified as a “Habitat Linkage/Wildlife Corridor,” and there is a “Habitat Connectivity Connection with Surrounding Open Space” associated with the Forrester Creek portion of the site and adjacent golf course (Figure 5-3 in City of Santee 2025). The Draft City of Santee MSCP Subarea Plan also maps a “Coastal California Gnatcatcher Stepping Stone Linkage” across the easternmost portion of the Project Site to connect two mapped “Coastal Sage Scrub/Gnatcatcher Habitat Blocks” that are present in uplands that border the easternmost portion of the northern and southern Project Site boundaries. Figure 4.1-4 depicts the City of Santee MSCP Draft Subarea Plan San Diego River Corridor and coastal California gnatcatcher habitat blocks/linkages, mapped within and immediately adjacent to the Project Site.

The Project Site could potentially function as wildlife habitat for local populations of common mammal species.

Species most likely to use the Project Site include coyote (Canis latrans), mule deer (Odocoileus hemionus), raccoon (Procyon lotor), striped skunk (Mephitis mephitis), and Virginia opossum (Didelphis virginiana). Larger species, such as bobcat (Lynx rufus) and mountain lion (Puma concolor) are not expected to use this highly urbanized vicinity of the San Diego River Corridor due to the amount of adjacent commercial and industrial uses, large presence of human encampments, and general lack of connectivity to larger core areas of suitable habitat.

Bat roosting opportunities for multiple special-status bat species are present throughout the riparian habitats surrounding San Diego River in the Project Site but surrounding commercial and residential development causes noise disturbance. In addition, no diagnostic signs of bird rookeries (e.g., numerous nests, whitewash) or large maternal or overwintering bat roosts (e.g., large concentrations of guano or guano odors) were identified in the Project Site during the biological reconnaissance field surveys. Therefore, it is unlikely for the Project Site to support wildlife nursery sites.

The Project Site contains multiple native vegetation communities that could provide nesting habitat for birds protected under the Migratory Bird Treaty Act and California Fish and Game Code Sections 3503, 3503.5, and 3513. These include raptors and special-status wildlife species as well as common species adapted to urban environments.

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4.1.2 Relevant Plans, Policies, and Ordinances
Federal
Federal Endangered Species Act
The federal Endangered Species Act (FESA) of 1973 (16 USC 1531 et seq.), as amended, is administered by USFWS for most plant and animal species, and by the National Oceanic and Atmospheric Administration National Marine Fisheries Service for certain marine species. This legislation is intended to provide a means to conserve the ecosystems upon which endangered and threatened species depend, and provide programs for the conservation of those species, thus preventing the extinction of plants and wildlife. FESA defines an endangered species as “any species that is in danger of extinction throughout all or a significant portion of its range.” A threatened species is defined as “any species that is likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range.” Under FESA, it is unlawful to “take” any listed species; “take” is defined as, “harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect, or to attempt to engage in any such conduct.” FESA allows for the issuance of incidental take permits for listed species under Section 7, which is generally available for projects that also require other federal agency permits or other approvals, and under Section 10, which provides for the approval of habitat conservation plans (HCPs) on private property without any other federal agency involvement.

Migratory Bird Treaty Act
The Migratory Bird Treaty Act prohibits the intentional and unintentional take of any migratory bird or any part, nest, or eggs of any such bird. Under the Migratory Bird Treaty Act, “take” is defined as pursuing, hunting, shooting, capturing, collecting, or killing, or attempting to do so (16 USC 703 et seq.). Currently, the Migratory Birds office considers nests that support eggs, nestlings, or juveniles to be active. 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). Executive Order 13186 requires federal agencies to work with USFWS to develop a Memorandum of Understanding. USFWS reviews actions that might affect these species.

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Project Boundary
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City of Santee Draft MSCP Subarea Plan Boundary
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San Diego River Subunit (Draft Santee MSCP Subarea Plan (City of Santee 2025)) San Diego River Corridor Ordinance (Draft Santee MSCP Subarea Plan (City of Santee 2025)) Date: 4/16/2026 User: cgardner Path: Z:\Projects\j1861101\MAPDOC\San Diego River Fire Hazard Mitigation Plan EIR\San Diego River Fire Hazard Mitigation Plan EIR.aprx Map: Figure 4.1-6 MSCP Lands Layout: Figure 4.1-6 MSCP Lands 0 500 1,000
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FIGURE 4.1-6

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Clean Water Act
The CWA provides guidance for the restoration and maintenance of the chemical, physical, and biological integrity of the nation’s waters. Section 401 requires a project operator for a federal license or permit that allows activities resulting in a discharge to waters of the United States to obtain state certification, thereby ensuring that the discharge would comply with provisions of the CWA. The RWQCBs administer the certification program in California.

Section 402 establishes a permitting system for the discharge of any pollutant (except dredged or fill material) into waters of the United States. Section 404 establishes a permit program administered by USACE that regulates the discharge of dredged or fill material into waters of the United States, including wetlands. USACE implementing regulations are found in the Code of Federal Regulations (CFR) at 33 CFR Parts 320 to 332. Guidelines for implementation are referred to as the Section 404(b)(1) Guidelines, which were developed by the U.S.

Environmental Protection Agency in conjunction with USACE (40 CFR 230). The guidelines allow the discharge of dredged or fill material into the aquatic system only if there is no practicable alternative that would have less adverse impacts. Wetlands and Other Waters of the United States Based on a recent court case ordering vacation of the Navigable Waters Protection Rule, USACE and the U.S.

Environmental Protection Agency have halted implementation of the rule and are interpreting waters of the United States consistent with the pre-2015 regulatory regime until further notice. Per 33 CFR 328.3(a), waters of the United States are defined as follows:

1. All waters which are currently used, or were used in the past, or may be susceptible to use in interstate or foreign commerce, including all waters which are subject to the ebb and flow of the tide;

2. All interstate waters including interstate wetlands;

3. All other waters such as intrastate lakes, rivers, streams (including intermittent streams), mudflats, sandflats, wetlands, sloughs, prairie potholes, wet meadows, playa lakes, or natural ponds, the use, degradation or destruction of which could affect interstate or foreign commerce including any such waters:
a. Which are or could be used by interstate or foreign travelers for recreational or other purposes; or b. From which fish or shellfish are or could be taken and sold in interstate or foreign commerce; or c. Which are used or could be used for industrial purposes by industries in interstate commerce;

4. All impoundments of waters otherwise defined as waters of the United States under this definition;

5. Tributaries of waters identified in paragraphs (a)(1) through (4) of this section;

6. The territorial seas;

7. Wetlands adjacent to waters (other than waters that are themselves wetlands) identified in paragraphs (a)(1) through (6) of this section; and

8. Waste treatment systems, including treatment ponds or lagoons designed to meet the requirements of CWA (other than cooling ponds as defined in 40 CFR 423.11(m) which also meet the criteria of this definition) are not waters of the United States.

The USACE/U.S. Environmental Protection Agency Rapanos Guidance states that USACE will regulate traditional navigable waters and adjacent wetlands, and relatively permanent waters tributary to traditional navigable waters and adjacent wetlands. Non-relatively permanent waters (those exhibiting less than 3 months of continuous surface flows) and their adjacent wetlands would be regulated if there is a significant nexus from the site to traditional navigable waters.

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The State Water Resources Control Board has authority over wetlands through Section 401 of the CWA, as well as the Porter–Cologne Act, California Code of Regulations Section 3831(k), and California Wetlands Conservation Policy. The CWA requires that an applicant for a Section 404 permit (to discharge dredge or fill material into waters of the United States) first obtain certification from the appropriate state agency stating that the fill is consistent with the state’s water quality standards and criteria. In California, the authority to either grant certification or waive the requirement for permits is delegated by the State Water Resources Control Board to the nine RWQCBs. A request for certification is submitted to the RWQCB at the same time that an application is filed with USACE.

State
California Endangered Species Act
The California Endangered Species Act (CESA) (California Fish and Game Code Sections 2050–2068) provides protection for and prohibits the take of plant, fish, and wildlife species listed by the State of California. Unlike FESA, under CESA, state-listed plants have the same degree of protection as wildlife, but insects and other invertebrates may not be listed. Take is defined similarly to FESA and is prohibited for both listed and candidate species. Take authorization may be obtained by a project applicant from CDFW under CESA Section 2081, which allows take of a listed species for educational, scientific, or management purposes. In this case, developers consult with CDFW to develop a set of measures and standards for managing the listed species, including full mitigation for impacts, funding of implementation, and monitoring of mitigation measures.

California Fish and Game Code
Fully Protected Species
Sections 3511, 4700, 5050, and 5515 of the California Fish and Game Code outline protection for fully protected species of mammals, birds, reptiles, amphibians, and fish. Species that are fully protected by these sections may not be taken or possessed at any time. CDFW cannot issue permits or licenses that authorize the “take” of any fully protected species, except under certain circumstances, such as scientific research and live capture and relocation of such species pursuant to a permit for the protection of livestock. On July 10, 2023, Senate Bill 147 was signed into law and amends the California Fish and Game Code to allow a 10-year permitting mechanism for a defined set of projects within the renewable energy, transportation, and water infrastructure sectors. Furthermore, it is the responsibility of the CDFW to maintain viable populations of all native species. Toward that end, CDFW has designated certain vertebrate species as Species of Special Concern, because declining population levels, limited ranges, and/or continuing threats have made them vulnerable to extinction.

Sections 1600–1616
CDFW jurisdiction includes ephemeral, intermittent, and perennial watercourses (including dry washes) and lakes characterized by the presence of (1) definable bed and banks and (2) existing fish or wildlife resources. CDFW takes jurisdiction to the top of bank of the stream, or the limit of the adjacent riparian vegetation, which may include oak woodlands in canyon bottoms. Historical court cases have further extended CDFW jurisdiction to include watercourses that seemingly disappear but reemerge elsewhere. Under the CDFW definition, a watercourse need not exhibit evidence of an ordinary high water mark to be claimed as jurisdictional. CDFW does not have jurisdiction over ocean or shoreline resources.

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Under California Fish and Game Code Sections 1600–1616, CDFW has the authority to regulate work that will substantially divert or obstruct the natural flow of, or substantially change or use any material from, the bed, channel, or bank of any river, stream, or lake. CDFW also has the authority to regulate work that will deposit or dispose of debris, waste, or other material containing crumbled, flaked, or ground pavement where it may pass into any river, stream, or lake. This regulation takes the form of a requirement for a Lake or Streambed Alteration Agreement and is applicable to all projects. Applications to CDFW must include a complete certified California Environmental Quality Act (CEQA) document.

California Native Plant Protection Act
The Native Plant Protection Act of 1977 (see Section 1900 et seq. of the California Fish and Game Code) directed CDFW to carry out the legislature’s intent to “preserve, protect and enhance rare and endangered plants in this State.” The Native Plant Protection Act gave the California Fish and Game Commission the power to designate native plants as “endangered” or “rare” and protect endangered and rare plants from take. CESA expanded on the original Native Plant Protection Act and enhanced legal protection for plants, but the Native Plant Protection Act remains part of the California Fish and Game Code. To align with federal regulations, CESA created the categories of “threatened” and “endangered” species. It converted all “rare” animals into the act as threatened species but did not do so for rare plants. Thus, there are three listing categories for plants in California: rare, threatened, and endangered. Because rare plants are not included in CESA, mitigation measures for impacts to rare plants are specified in a formal agreement between CDFW and the Project proponent.

Nesting Birds
Section 3503 of the California Fish and Game Code states that it is unlawful to take, possess, or needlessly destroy the nests or eggs of any bird, except as otherwise provided by this code or any regulation made pursuant thereto.

Section 3503.5 protects all birds of prey (raptors) and their eggs and nests. Section 3511 states that fully protected birds or parts thereof may not be taken or possessed at any time. Section 3513 states that it is unlawful to take or possess any migratory non-game bird as designated in the Migratory Bird Treaty Act.

California Environmental Quality Act
CEQA requires identification of a project’s potentially significant impacts on biological resources and ways that such impacts can be avoided, minimized, or mitigated. CEQA also provides guidelines and thresholds for use by lead agencies for evaluating the significance of proposed impacts.

The State of California CEQA Guidelines (CEQA Guidelines) Section 15380(b)(1) defines endangered animals or plants as species or subspecies whose “survival and reproduction in the wild are in immediate jeopardy from one or more causes, including loss of habitat, change in habitat, overexploitation, predation, competition, disease, or other factors.” A rare animal or plant is defined in Section 15380(b)(2) as a species that, although not presently threatened with extinction, exists “in such small numbers throughout all or a significant portion of its range that it may become endangered if its environment worsens; or … [t]he species is likely to become endangered within the foreseeable future throughout all or a significant portion of its range and may be considered ‘threatened’ as that term is used in the federal Endangered Species Act.” Additionally, an animal or plant may be presumed to be endangered, rare, or threatened if it meets the criteria for listing, as defined further in CEQA Guidelines Section 15380(c).

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CDFW has developed a list of “Special Species” as “a general term that refers to all of the taxa the California Natural Diversity Database is interested in tracking, regardless of their legal or protection status.” This is a broader list than those species that are protected under FESA, CESA, and other California Fish and Game Code provisions, and includes lists developed by other organizations, including, for example, the Audubon Watch List Species. Guidance documents prepared by other agencies, including the U.S. Bureau of Land Management’s Sensitive Species and USFWS Birds of Special Concern, are also included on this CDFW Special Species list. Additionally, CDFW has concluded that plant species listed as CRPR 1 and 2 by the California Native Plant Society, and potentially some CRPR 3 plants, are covered by CEQA Guidelines Section 15380.

Section IV, Appendix G (Environmental Checklist Form), of the CEQA Guidelines requires an evaluation of impacts to “any riparian habitat or other sensitive natural community identified in local or regional plans, policies, regulations or by CDFW or USFWS.”
Porter–Cologne Water Quality Control Act
Pursuant to provisions of the Porter–Cologne Act, the RWQCBs regulate discharging waste, or proposing to discharge waste, within any region that could affect a water of the state (California Water Code, Section 13260[a]).

The State Water Resources Control Board defines a waters of the state as “any surface water or groundwater, including saline waters, within the boundaries of the state” (California Water Code, Section 13050[e]). All waters of the United States are waters of the state. Waters of the state include wetlands, and the State Water Resources Control Board definition of wetlands includes the following:

1. Natural wetlands.

2. Wetlands created by modification of a surface water of the state.

3. Artificial wetlands that meet any of the following criteria:
a. Approved by an agency as compensatory mitigation for impacts to other waters of the state, except where the approving agency explicitly identifies the mitigation as being of limited duration.
b. Specifically identified in a water quality control plan as a wetland or other water of the state.
c. Resulted from historic human activity, is not subject to ongoing operation and maintenance, and has become a relatively permanent part of the natural landscape. d. Greater than or equal to 1 acre in size unless the artificial wetland was constructed and is currently used and maintained, primarily for one or more of the following purposes:
industrial or municipal wastewater treatment or disposal; settling of sediment; detention, retention, infiltration, or treatment of stormwater runoff and other pollutants or runoff subject to regulation under a municipal, construction, or industrial permitting program; treatment of surface waters; agricultural crop irrigation or stock watering; fire suppression; industrial processing or cooling water; active surface mining – even if the site is managed for interim wetlands functions and values; log storage; treatment, storage, or distribution of recycled water; maximizing groundwater recharge (this does not include wetlands that have incidental groundwater recharge benefits); or fields flooded for rice growing.

Wetlands that may not meet all of USACE’s wetland delineation criteria are considered wetland waters of the state if, “under normal circumstances, (1) the area has continuous or recurrent saturation of the upper substrate caused

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by groundwater, or shallow surface water, or both; (2) the duration of such saturation is sufficient to cause anaerobic conditions in the upper substrate; and (3) the area’s vegetation is dominated by hydrophytes or the area lacks vegetation” (SWRCB 2021). Additionally, aquatic resources that USACE determines to not be waters of the United States because they lack a significant nexus to a traditional navigable water or are above the ordinary high water mark limit of federal jurisdiction may also be considered waters of the state. If a CWA Section 404 permit is not required for a project, RWQCB may still require a permit (waste discharge requirements) for impacts to waters of the state under the Porter–Cologne Act.

Local
Multiple Species Conservation Program Plan
The Project Site is within the boundaries of the San Diego MSCP Plan (City of San Diego 1998). The MSCP Plan is a multijurisdictional habitat conservation planning program that involves USFWS, CDFW, the County of San Diego, the Cities of San Diego and Chula Vista, and other local jurisdictions and special districts. Local jurisdictions and special districts implement the MSCP Plan for their respective portions through subarea plans. The combination of the MSCP Plan and subarea plans serve as an HCP pursuant to FESA Section 10(a)(1)(B), and as a natural community conservation plan pursuant to the California Natural Community Conservation Planning Act of 1991 (City of San Diego 1998).

The MSCP Plan study area encompasses 582,243 acres within the southwestern portion of San Diego County. As stated in the MSCP Plan, an objective of the MSCP is to conserve a connected system of biologically viable habitat lands in a manner that maximizes the protection of sensitive species and precludes the need for future listings of species as threatened or endangered. The MSCP Plan identifies a Multi-Habitat Planning Area (MHPA), which is the area within which the permanent MSCP Preserve is assembled and managed for its biological resources. The MHPA is defined in many areas by mapped boundaries in figures in the MSCP Plan and is also defined by quantitative targets for conservation of vegetation communities and goals and criteria for Preserve design. The MSCP Plan targets 171,917 acres within the MHPA for conservation (City of San Diego 1998).

A total of 85 plant and animal species are “covered” by the MSCP Plan. The MSCP Plan Final Environmental Impact Report/Environmental Impact Statement (City of San Diego 1998) identifies “Vegetation Community Conservation Target Areas” for conservation by subarea (Attachment B of the MSCP Plan [City of San Diego 1998]). A total of 2,067 acres is expected to be conserved within the Santee Subarea MHPA. With approval of each subarea plan and corresponding implementing agreement, each participating local jurisdiction receives permits and/or authorization to directly impact or take MSCP Covered Species. The Covered Species include species listed as endangered or threatened by FESA and/or CESA, as well as unlisted species. Table 3-5 in the MSCP Plan provides a list of the MSCP Covered Species, and includes specific conditions required for take authorizations (City of San Diego 1998).

Draft Santee Multiple Species Conservation Program Subarea Plan The City of Santee has been preparing its subarea plan since the original approval of the San Diego MSCP Plan and is currently in the process of completing the Santee MSCP Subarea Plan. Although the Draft Santee MSCP Subarea Plan has not yet been approved or permitted, it is used as the guidance document for projects occurring within the City of Santee. The current Draft Santee MSCP Subarea Plan seeks coverage for up to 23 species, and relies on a combination of hardline conservation areas, criteria-based upland standards areas, San Diego River conservation opportunities areas, and City-owned preserve lands to protect species and habitat (City of Santee 2025). Coverage for

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species is dependent on a number of factors, including multijurisdictional participation, adequate building of the Preserve system, adequate protection of certain populations, permanent management funding, and other factors.

The Draft Santee MSCP Subarea Plan Preserve boundaries are a result of the City of Santee’s efforts to refine and expand the MHPA boundaries, to better define conservation priorities within the City of Santee, and to formulate an HCP under the MSCP Plan. Because the Draft Santee MSCP Subarea Plan is still in development, portions of the subarea plan may still change, including Hardline Preserve areas and Covered Species. As shown in Figure 4.1-6, the majority of the Project Site is located within Draft Santee MSCP Subarea Plan (City of Santee 2025).

4.1.3 Thresholds of Significance
The significance criteria used to evaluate Project impacts to biological resources are based on CEQA Guidelines Appendix G. Potential Project-related impacts analyzed in this section account for biological resources that occur or have the potential to occur on the Project Site. According to CEQA Guidelines Appendix G, a significant impact related to biological resources would occur if the Project would result in the following:

A. 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.

B. 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.

C. 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.

D. 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.

E. Conflict with any local policies or ordinances protecting biological resources, such as a tree preservation policy or ordinance.

F. Conflict with the provisions of an adopted Habitat Conservation Plan, Natural Community Conservation Plan, or other approved local, regional, or state habitat conservation plan.

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4.1.4 Impact Analysis
A. 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 Species
Direct Impacts
One special-status plant species was observed within the Project Site: San Diego marsh-elder. White rabbittobacco has also been documented immediately outside of the Project Site boundary (Figure 4.1-2). Both San Diego marsh-elder and white rabbit-tobacco are not Covered Species under the City of Santee Draft MSCP Subarea Plan. Further, the native vegetation communities within the Project Site have potential to support an additional five special-status plant species with a moderate to high potential to occur on the Project Site. These species cannot be considered absent, as the focused botanical survey was conducted outside of the spring and summer blooming period.

The Project consists of removing hazardous (dead or dying/diseased) non-native trees from within Zone 3 of the Project Site, as well as native and non-native brush thinning in upland defensible space areas (Zones 1 and 2). Special-status plant species present or considered present (San Diego marsh-elder and white rabbit-tobacco) and the five additional special-status plant species determined to have a moderate to high potential to occur on the Project Site could be present in native habitats located in Zones 1 to 3. Direct impacts to special-status plants from vegetation management activities would be considered potentially significant. The Project shall completely avoid directly impacting special-status plants located in Zones 1 to 3 through implementation of MM BIO-1: Pre-construction Survey and Special-Status Plant Species Avoidance. As such, direct impacts to special-status plant species would be less than significant.

Indirect Impacts
Fuel Treatments identified as part of the vegetation management and maintenance activities (manual, mechanical, and chemical) could result in decreased water quality and altered hydrology, soil compaction, elevated dust levels, and the spread of invasive plant species. Potentially significant indirect impacts on special-status plant species would be avoided through implementation of MM BIO-1, MM BIO-2: Standard Best Management Practices (BMPs), and MM BIO-3: Biological Monitor. With implementation of these measures, indirect impacts to special-status plant species would be less than significant.

Special-Status Wildlife Species
Direct Impacts
There are 24 special-status wildlife species that are known to occur within the Project Site or have a moderate to high potential to occur within the native portions of the Project Site, in both uplands (coastal sage scrub) and wetland/riparian habitats (southern arroyo willow riparian forest, southern cottonwoodwillow riparian forest, mulefat scrub, southern willow scrub, emergent wetland, freshwater marsh, disturbed wetland) (Table 4.1-1). Impacts to individuals would be unlikely during Project implementation due to the

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mobility of these species to move out of harm’s way. However, the Project would implement MM BIO-3 to ensure no special-status species would be injured or harmed during Project activities.

Suitable nesting riparian habitat for least Bell’s vireo, yellow-breasted chat, and yellow warbler is present in Zones 1 and 2 of the Project Site (Figures 4.1-3A, 4.1-3C, 4.1-3D, and 4.1-3E). Treatment activities occurring within riparian habitat are not anticipated to result in removal of habitat for these special-status species. However, it is possible that unanticipated impacts (e.g., sensitive vegetation removal) to riparian habitat could occur, which would be considered significant and require mitigation. If unanticipated impacts to sensitive vegetation, the Project would implement MM BIO-4: Sensitive Vegetation Communities. MM BIO-4 would require mitigation for any unanticipated significant impacts to riparian habitat within Zones 1 and 2 in accordance with the mitigation ratios in Table 5-13 of the Draft Santee MSCP Subarea Plan (City of Santee 2025). Additionally, the Project would implement MM BIO-5: Avoidance of Listed Species Take:

Least Bell’s Vireo, to ensure all Project activities occur outside the least Bell’s vireo breeding season (March 15 through September 15). No impacts to native riparian habitat are anticipated within Zone 3, which would only result in the dead/dying and invasive species removal, and all Project activities would occur outside the least Bell’s vireo breeding season. If any unintended impacts occur to riparian habitat within Zone 3, then MM BIO-4 would be implemented.

Although a very limited amount is proposed, thinning of approximately 3 acres of non-contiguous areas (i.e., thinning would occur in unconnected slivers across many polygons throughout the Project Site) of coastal sage scrub has the potential to adversely impact coastal California gnatcatchers known to nest within that vegetation community. Treatment activities occurring within coastal sage scrub are not anticipated to result in the removal of suitable habitat for coastal California gnatcatcher. However, if Project activities result in unintended impacts to coastal sage scrub, then these impacts would be considered significant and require mitigation. Therefore, implementation of MM BIO-4 would require mitigation for any unintended impacts to coastal sage scrub habitat within Zones 1 and 2 in accordance with the mitigation ratios in Table 5-13 of the Draft Santee MSCP Subarea Plan (City of Santee 2025). Implementation of MM BIO-6: Avoidance of Listed Species Take: Coastal California Gnatcatcher, would ensure all Project activities occur outside the coastal California gnatcatcher breeding season (March 1 to August 15). No impacts to coastal sage scrub habitat are anticipated within Zone 3, which would only result in the dead/dying, and invasive species removal, and all Project activities would occur outside the coastal California gnatcatcher breeding season.

If any unintended impacts occur within Zone 3, then MM BIO-4 would be implemented.

Although no evidence of roost or nursery sites was identified on the Project Site during the biological reconnaissance field surveys, impacts (e.g., tree removal in Zone 3, etc.) to maternity bat roosts would be significant. The Project would avoid the native bat breeding season (i.e., April 1 through August 31), as it overlaps the nesting bird season as required by MM BIO-7: Nesting Bird Survey. Additionally, implementation of MM BIO-3: Biological Monitor would ensure no special-status bat species or native bat colonies or maternity roosts would be injured or harmed during Project activities through establishment of a buffer if these resources are observed.

The Project Site supports multiple wetland and upland habitats that contain suitable vegetation for nesting and migratory birds and raptors protected by the Migratory Bird Treaty Act and Section 3500 of the California Fish and Game Code. The Project proposes to remove invasive and hazardous trees only, which have a low potential to support nesting birds compared to the high-quality surrounding native wetland and upland habitats along the San Diego River in the Project Site. All nesting bird habitat removal or thinning shall occur outside the nesting bird breeding season (February 15 through September 30) as directed by

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-61
MM BIO-7: Nesting Bird Survey. Implementation of MM BIO-3 shall also reduce potentially adverse impacts to nesting birds to a less-than-significant level by requiring a biological monitor be present to establish nest buffers if Project activities cannot avoid the avian nesting season. With implementation of these measures, potentially significant impacts to nesting and migratory birds would be reduced to less than significant.

Crotch’s bumble bee (Bombus crotchii) could occur within areas of the Project Site containing upland habitats and impacts to this species would be considered significant. Treatment activities occurring within upland habitats are not anticipated to result in the removal of suitable habitat for Crotch’s bumble bee.

However, if Project activities result in unintended impacts to upland habitats, then these impacts would be considered significant and require mitigation. Therefore, implementation of MM BIO-4 would require mitigation for impacts to sensitive upland communities within Zones 1 and 2 in accordance with the mitigation ratios in Table 5-13 of the Draft Santee MSCP Subarea Plan (City of Santee 2025).

Implementation of MM BIO-8: Avoidance of Listed Species Take: Crotch’s Bumble Bee, would require a preconstruction survey within Zones 1, 2, and 3 to ensure avoidance of impacts to individuals. No impacts to sensitive upland habitats are anticipated within Zone 3, which would only result in the dead/dying, and invasive species removal, and ground disturbance activities that could impact Crotch’s bumble bee nests are not anticipated in Zones 1, 2, or 3. If any unintended impacts occur within Zone 3, then MM BIO-4 would be implemented.

Indirect Impacts
There is potential for Project activities to have indirect impacts to special-status wildlife, including nesting birds, from decreased water quality and altered hydrology, soil compaction, elevated dust levels, and the spread of invasive plant species. These indirect impacts would be avoided through implementation of MM BIO-2 and MM BIO-3. As such, indirect impacts to special-status wildlife species would be less than significant.

B. 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?
Direct Treatment Footprint
A total of approximately 31.68 acres on the Project Site would be treated in Zones 1 and 2. Figures 4.1-7A through 4.1-7E, Impacts to Biological Resources, depict the spatial distribution of the three treatment zones with the biological resources observed on the Project Site. Table 4.1-5 details the vegetation communities within Zone 1 and Zone 2 that encompass the direct treatment footprint.

A total of 18.02 acres of sensitive vegetation communities would be treated within Zones 1 and 2, including

2.88 acres of sensitive vegetation communities within Zone 1 and 15.14 acres of sensitive vegetation communities within Zone 2. Although vegetation management within Zones 1 and 2 would include activities such as shrub trimming and grass mowing, all trimming activities would be done to industry standards (ISA, ANSI) to minimize likelihood of plant death. Vegetation management in Zones 1 and 2 is not expected to result in removal of any sensitive vegetation communities. However, if Project activities result in unintended impacts to sensitive vegetation communities, then these impacts would be considered significant and would require mitigation. Therefore, implementation of MM BIO-4 would require mitigation for any unintended impacts to sensitive vegetation communities in accordance with the mitigation ratios in Table

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-62
5-13 of the Draft Santee MSCP Subarea Plan (City of Santee 2025). A biological monitor shall be present in accordance with MM BIO-3 to ensure treatment and vegetation removal activities occur only within the designated areas.

Table 4.1-5. Vegetation Communities and Land Cover Types in Zones 1 and 2 Vegetation Community/Land Cover Type1
Project Site
(Acres) Sensitive (Y/N)2
Zone 1
Native Vegetation Communities
Coast Live Oak Woodland 0.07 Y
Mulefat Scrub 0.02 Y
Southern Arroyo Willow Riparian Forest 0.01 Y
Southern Cottonwood-Willow (Populus spp.- Salix spp.) Riparian Forest 2.13 Y Southern Riparian Scrub 0.02 Y
Southern Willow (Salix spp.) Scrub 0.14 Y
Diegan Coastal Sage Scrub (Including Baccharis-dominated subform) 0.50 Y Native Vegetation Communities Subtotal 2.89 N/A
Non-native Vegetation Communities and Land Cover Types
Eucalyptus Woodland 0.01 N
Non-native Woodland 0.02 N
Disturbed Habitat 5.18 N
Urban/Developed1 1.06 N
Non-native Vegetation Communities Subtotal 6.27 N/A
Zone 1 Subtotal 9.15 N/A
Zone 2
Native Vegetation Communities
Coast and Valley Freshwater Marsh 0.14 Y
Open Water 0.24 Y
Mulefat Scrub 0.13 Y
Southern Arroyo Willow Riparian Forest 0.13 Y
Southern Cottonwood-Willow Riparian Forest 8.78 Y
Southern Riparian Scrub 0.76 Y
Southern Willow Scrub 1.75 Y
Diegan Coastal Sage Scrub (Including Baccharis-dominated subform) 2.60 Y Coast Live Oak Woodland 0.61 Y
Native Vegetation Communities Subtotal 15.14 N/A
Non-native Vegetation Communities and Land Cover Types
Eucalyptus Woodland 0.34 N
Non-native Woodland 0.04 N
Disturbed Habitat 6.11 N
Urban/Developed1 0.90 N
Non-native Vegetation Communities Subtotal 7.39 N/A
Zone 2 subtotal 22.53 N/A

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-63
Table 4.1-5. Vegetation Communities and Land Cover Types in Zones 1 and 2 Vegetation Community/Land Cover Type1
Project Site
(Acres) Sensitive (Y/N)2
Total 31.68 N/A
Notes: N/A = not applicable. Totals may not sum due to rounding. 1 Fuel treatment in Urban/Developed land consists of any ornamental plantings, maintained grass, or other landscaping. 2 Vegetation community considered sensitive under the Draft Santee MSCP Subarea Plan (City of Santee 2025).

Vegetation management activities occurring in Zone 3 would only involve removal of dead, dying, or invasive species and as such, no direct impacts to sensitive vegetation communities are anticipated in Zone 3 from Project implementation. However, if any unintended impacts occur to sensitive vegetation communities within Zone 3, then MM BIO-4 would be implemented to reduce those impacts to less than significant. A biological monitor shall be present in accordance with MM BIO-3 to ensure vegetation management activities occur only for dead, dying, and invasive species. A total of 1,509 trees (or approximately 29.0 acres) are estimated for removal within Zone 3 as shown on Figures 4.1-7A through 4.1-7E. It should be noted that the data collected during field assessments is only a preliminary mapping of the potential areas slated for treatment within Zone 3. The Project would implement MM BIO-9: Tree Survey, to provide comprehensive mapping, by a Certified Arborist, of the dead, dying, and invasive species that would be removed under the proposed Project. The plant species identified during field assessments for the Fuels Treatment Plan presented in Table 4.1-6 are located in Zone 3 and are proposed for treatment.

Table 4.1-6. Plant Species Identified for Treatment or Removal in Zone 3 Non-tree Species Tree Species Tree Species Continued
Arrowweed
Arundo donax
Bamboo
Blackberry
Bougainvillea
California sagebrush
Cape honeysuckle
Castor bean
Desert broom
Pampas grass
Prickly Russian thistle
Smilo grass
Tobacco tree
Toyon
Yucca
Aleppo pine
American sweetgum
Arizona cypress
Arroyo willow
Shamel ash
Bottlebrush (spp.)
Brazilian pepper
California fan palm
Canary island date palm
Canary island pine
Carob
Carrotwood
Chinese elm
Chinese flame tree
Coast live oak
Date palm (spp.)
Eucalyptus (spp.)
Fan palm (spp.)
Fig (spp.)
Glossy privet
Golden raintree
Italian stone pine
Laurel sumac
Mexican fan palm
Monterey pine
Olive (spp.)
Paloverde (spp.)
Pepper tree (spp.)
Pine (spp.)
Red willow
Siberian elm
Silk oak
Tree of Heaven
Weeping Bottlebrush
Yellowwood (spp.)
Willow (spp.)
Notes: All native tree or non-tree species listed in the table would only be removed if the individual were dead or dying.

Indirect Impacts
Indirect impacts could occur to sensitive vegetation communities in Zones 1 to 3 through decreased water quality and altered hydrology, soil compaction, elevated dust levels, and the spread of invasive plant

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-64
species. These indirect impacts would be avoided through implementation of MM BIO-2 and MM BIO-3, as described in Section 4.1.5 below. As such, indirect impacts to sensitive vegetation communities would be less than significant.
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n
Feet
Project Boundary
Permanent Impacts
Zone 1
Zone 2
Zone 3
Sensitive Species
"J Yellow warbler
!P Yellow-breasted chat
0# least Bell's vireo
Invasive Plant Species Proposed for Removal
Potential Invasive Species/Dead and Dying Tree Removal Areas Cortaderia selloana (Uruguayan pampas grass)
Special-Status Plant Species
Iva hayesiana (San Diego marsh-elder)
Vegetation Communities and Land Covers
Sensitive Riparian Vegetation Communities
Sensitive Upland Vegetation Communities
CLOW, Coast Live Oak Woodland
CSS, Diegan Coastal Sage Scrub
CSSB, Diegan Coastal Sage Scrub: Baccharis-dominated
DEV, Urban/Developed
DH, Disturbed Habitat
DW, Disturbed Wetland
EUC, Eucalyptus Woodland
EW, Emergent Wetland
FWM, Coastal and Valley Freshwater Marsh
MFS, Mule Fat Scrub
NNR, Non-Native Riparian
NNW, Non-Native Woodland
NVC, Non-Vegetated Channel or Floodway
OW, Open Water
SCWRF, Southern Cottonwood-Willow Riparian Forest
SWS, Southern Willow Scrub
USFWS Critical Habitat
Least Bell's vireo
A
B
C
D
E
SOURCE: Vantor 2025; Open Street Map 2025
San Diego River Fire Hazard Mitigation Program EIR
Impacts to Biological Resources
FIGURE 4.1-7A

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-66

CSSB CSSB
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n
Feet
Project Boundary
Permanent Impacts
Zone 1
Zone 2
Zone 3
Invasive Plant Species Proposed for Removal
Potential Invasive Species/Dead and Dying Tree Removal Areas Arundo donax (giant reed)
Special-Status Plant Species
Iva hayesiana (San Diego marsh-elder)
Vegetation Communities and Land Covers
Sensitive Riparian Vegetation Communities
Sensitive Upland Vegetation Communities
CLOW, Coast Live Oak Woodland
CSS, Diegan Coastal Sage Scrub
CSSB, Diegan Coastal Sage Scrub: Baccharis-dominated
DEV, Urban/Developed
DH, Disturbed Habitat
EUC, Eucalyptus Woodland
EW, Emergent Wetland
FWM, Coastal and Valley Freshwater Marsh
NNG, Non-Native Grassland
NNR, Non-Native Riparian
OW, Open Water
SCWRF, Southern Cottonwood-Willow Riparian Forest
SWS, Southern Willow Scrub
A
B
C
D
E
SOURCE: Vantor 2025; Open Street Map 2025
San Diego River Fire Hazard Mitigation Program EIR
Impacts to Biological Resources
FIGURE 4.1-7B

4.1 – BIOLOGICAL RESOURCES
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n
Feet
Project Boundary
Permanent Impacts
Zone 1
Zone 2
Zone 3
Sensitive Species
"J Yellow warbler
0# least Bell's vireo
Invasive Plant Species Proposed for Removal
Potential Invasive Species/Dead and Dying Tree Removal Areas Arundo donax (giant reed)
Special-Status Plant Species
White rabbit-tobacco (Pseudognaphalium leucocephalum)
Vegetation Communities and Land Covers
Sensitive Riparian Vegetation Communities
Sensitive Upland Vegetation Communities
CLOW, Coast Live Oak Woodland
CSS, Diegan Coastal Sage Scrub
CSSB, Diegan Coastal Sage Scrub: Baccharis-dominated
DEV, Urban/Developed
DH, Disturbed Habitat
EUC, Eucalyptus Woodland
EW, Emergent Wetland
FWM, Coastal and Valley Freshwater Marsh
NNG, Non-Native Grassland
OW, Open Water
SCWRF, Southern Cottonwood-Willow Riparian Forest
SWRF, Southern Arroyo Willow Riparian Forest
TS, Tamarisk Scrub
A
B
C
D
E
SOURCE: Vantor 2025; Open Street Map 2025
San Diego River Fire Hazard Mitigation Program EIR
Impacts to Biological Resources
FIGURE 4.1-7C

4.1 – BIOLOGICAL RESOURCES
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Project Boundary
Permanent Impacts
Zone 1
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Zone 3
Sensitive Species
"J Yellow warbler
!P Yellow-breasted chat
0# least Bell's vireo
Invasive Plant Species Proposed for Removal
Potential Invasive Species/Dead and Dying Tree Removal Areas Arundo donax (giant reed)
Special-Status Plant Species
Iva hayesiana (San Diego marsh-elder)
Vegetation Communities and Land Covers
Sensitive Riparian Vegetation Communities
Sensitive Upland Vegetation Communities
CLOW, Coast Live Oak Woodland
CSS, Diegan Coastal Sage Scrub
DEV, Urban/Developed
DH, Disturbed Habitat
FWM, Coastal and Valley Freshwater Marsh
NNW, Non-Native Woodland
OW, Open Water
SCWRF, Southern Cottonwood-Willow Riparian Forest
SRS, Southern Riparian Scrub
SWRF, Southern Arroyo Willow Riparian Forest
SWS, Southern Willow Scrub
A
B
C
D
E
SOURCE: Vantor 2025; Open Street Map 2025
San Diego River Fire Hazard Mitigation Program EIR
Impacts to Biological Resources
FIGURE 4.1-7D

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-72

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Woodside Ave
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Security Way
Los Sanderos Dr
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Karerllyn Dr
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Permanent Impacts
Zone 1
Zone 2
Zone 3
Sensitive Species
!P Yellow-breasted chat
"J coastal California gnatcatcher
Invasive Plant Species Proposed for Removal
Potential Invasive Species/Dead and Dying Tree Removal Areas Arundo donax (giant reed)
Vegetation Communities and Land Covers
Sensitive Riparian Vegetation Communities
Sensitive Upland Vegetation Communities
CLOW, Coast Live Oak Woodland
CLOWO, Open Coast Live Oak Woodland
CSS, Diegan Coastal Sage Scrub
CSSB, Diegan Coastal Sage Scrub: Baccharis-dominated
DEV, Urban/Developed
DH, Disturbed Habitat
FWM, Coastal and Valley Freshwater Marsh
NNR, Non-Native Riparian
NNW, Non-Native Woodland
OW, Open Water
SCWRF, Southern Cottonwood-Willow Riparian Forest
SWRF, Southern Arroyo Willow Riparian Forest
SWS, Southern Willow Scrub
A
B
C
D
E
SOURCE: Vantor 2025; Open Street Map 2025
San Diego River Fire Hazard Mitigation Program EIR
Impacts to Biological Resources
FIGURE 4.1-7E

4.1 – BIOLOGICAL RESOURCES
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EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-75
C. 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? Direct Treatment Footprint
Table 4.1-7 summarizes the treatment footprint containing potentially jurisdictional aquatic resource acreages within Zone 1 and Zone 2 on the Project Site. A total of approximately 14.98 acres of potentially jurisdictional aquatic resources would be treated within the Project Site as a result of the native and nonnative brush thinning located up to 100 feet from the edge of the existing development areas. The ultimate decisions on the amount and location of jurisdictional aquatic resources would be made by the resource agencies (i.e., USACE, CDFW, and RWQCB).

Table 4.1-7. Potentially Jurisdictional Aquatic Resources Within Zones 1 and 2 Impact Zone
Non-wetland Water/
Streambed Acreage
Wetland/Riparian
Habitat Acreage Total Acreage
Zone 1 0.03 2.37 2.40
Zone 2 0.68 11.90 12.58
Total 0.71 14.27 14.98
Notes: Vegetation management activities occurring in Zone 3 would only involve removal of dead, dying, or invasive species and as such, no direct impacts to potentially jurisdictional resources in Zone 3 are anticipated from Project implementation.

Treatment activities to jurisdictional aquatic resources occurring within Zones 1 and 2 would require regulatory resources permitting from the appropriate resource agencies (USACE, RWQCB, and CDFW) (MM BIO-10: Jurisdictional Aquatic Resources Permitting). A biological monitor shall be present in accordance with MM BIO-3 to ensure treatment and vegetation removal activities occur in accordance with the Project’s aquatic resource permits and there are no direct impacts occurring outside the designated areas. Mitigation Measure MM BIO-11: Jurisdictional Aquatic Resource Avoidance, would be implemented to further avoid impacting streams by using temporary rubber mats or pads to distribute weight and minimize vegetation trampling and soil disturbance, and helicopter and/or crane removal where equipment access is constrained and hand carry is infeasible. Treatment activities occurring within Zones 1 and 2 are not anticipated to result in the removal or filling of any jurisdictional aquatic resources. However, if Project activities result in any unintended impacts to jurisdictional aquatic resources, then these impacts would be considered significant and require mitigation. Therefore, implementation of MM BIO-4 would require mitigation for any unintended impacts to jurisdictional aquatic resources within Zones 1 and 2 in accordance with the mitigation ratios in Table 5-13 of the Draft Santee MSCP Subarea Plan (City of Santee 2025).

Vegetation management activities occurring in Zone 3 would only involve removal of dead, dying, or invasive species and as such, no direct impacts from removal or filling to potentially jurisdictional resources in Zone 3 are anticipated from Project implementation. If any unintended impacts occur to riparian habitat within Zone 3 then MM BIO-4 would be implemented. Mitigation Measure MM BIO-11: Jurisdictional Aquatic Resource Avoidance, would be implemented to ensure activities occurring in Zone 3 would only involve treatment or removal of dead, dying, or invasive species. As directed by MM BIO-11, the Project is committed to avoiding impacts to streams by using temporary rubber mats or pads to distribute weight and minimize vegetation trampling and soil disturbance, and helicopter and/or crane removal where equipment access is constrained and hand carry is infeasible. A biological monitor shall be present in accordance with MM BIO-3 to ensure treatment and vegetation removal activities do not impact any aquatic resource areas

4.1 – BIOLOGICAL RESOURCES
EIR FOR SAN DIEGO RIVER FIRE HAZARD MITIGATION PROGRAM: FUELS TREATMENT PLAN 18611.01 JULY 2026 4.1-76
located within Zone 3. As such, direct impacts to jurisdictional aquatic resources within Zone 3 would be avoided.

Indirect Impacts
Indirect impacts could occur to jurisdictional aquatic resources through decreased water quality and altered hydrology, soil compaction, elevated dust levels, and the spread of invasive plant species. These indirect impacts would be avoided through implementation of MM BIO-2 and MM BIO-3, as described in Section 4.1.5 below. As such, indirect impacts to jurisdictional aquatic resources would be less than significant.

D. 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?
The western portion of the San Diego River in the Project Site from Forester Creek up to Mast Park and the eastern portion of the Project Site are mapped as a wildlife corridors and linkage area, as shown on Figure 4.1-4. The western portion of the site is mapped as critical habitat for the least Bell’s vireo (Figure 4.1-3). The purpose of the Project is fuel hazard management that shall not modify the width of the San Diego River, its tributary (Forester Creek), or modify its land use as Open Space. Additionally, tree removal and native brush thinning would improve fuel hazard risk within the San Diego River Corridor, reducing forest fires that adversely impact the San Diego River’s function as a wildlife corridor due to habitat and species loss. Removal of non-native vegetation would improve the overall quality of the San Diego River as a wildlife corridor by reducing competition for resources from invasives that are usable for native wildlife species. Native brush thinning is not expected to adversely impact nursery sites or wildlife corridors through avoidance of the nesting bird season, and the loss of habitat is marginal compared to the net benefit of hazardous fuel reduction for fire management within the San Diego River Corridor. As a result, implementation of the Project would result in less-than-significant impacts to wildlife corridors and nursery sites.

E. Would the Project conflict with any local policies or ordinances protecting biological resources, such as a tree preservation policy or ordinance?
No conflicts with local policies and ordinances are anticipated from Project implementation. The Project would comply with the Section 8.06 of the Santee Municipal Code, and biological resources policies within the Conservation Element as no development is proposed, and the Project seeks to improve the San Diego River and Forester Creek through fuel reduction of mostly non-native trees and trees that are dead or decaying. Therefore, the Project is consistent with respect to the relevant City of Santee biological, floodway, and urban forestry municipal codes as well as the goals outlined in the City of Santee General Plan Conservation Element. The Project would comply with the City of Santee’s municipal code as well as the biological resources policies outlined within the City of Santee General Plan Conservation Element.

Furthermore, City of Santee staff shall review the Project to ensure there are no conflicts with the objectives and policies presented in the Conservation Element of the Santee General Plan and relevant urban forestry, floodway, and biological resources ordinances (City of Santee 2025; City of Santee 2003).

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F. 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? Although the Draft Santee MSCP Subarea Plan has not yet been approved or permitted, it is used as the guidance document for projects occurring within the City of Santee. As such, BMPs included in Section 5.5 of the Subarea Plan have been incorporated into the Project-specific mitigation measures below.

The majority of Zones 1 and 2 overlap defensible space areas identified within the San Diego River Subunit as shown on Figure 4-5 of the City of Santee Draft MSCP Subarea Plan, and Zone 3 is identified as a fuel hazard reduction area (City of Santee 2025). Because this is a fuel hazard reduction project (as opposed to a development project) that is designed to target removal of non-native vegetation within the San Diego River Corridor wildland–urban interface, no permanent removal of habitat is anticipated. Any trimming or thinning of native vegetation shall occur only following acquisition of required permits. Project implementation would not conflict with the provisions of the San Diego County MSCP or Draft Santee MSCP Subarea Plan, nor would it prevent the Draft Santee MSCP Subarea Plan from being approved or compromise continued implementation of the MSCP in San Diego County.

4.1.5 Mitigation Measures and Level of Significance
After Mitigation
The following mitigation measures shall be implemented to avoid and reduce potentially significant impacts to sensitive and riparian vegetation communities, special-status species, and potentially jurisdictional aquatic resources to a less-than-significant level. Any removal or pruning of native vegetation shall occur only following acquisition of required permits.

MM BIO-1 Pre-Construction Survey and Special-Status Plant Species Avoidance. No vegetation management activities occurring in Zone 3 or other native and non-native brush thinning occurring in Zones 1 and 2 shall occur within known populations of San Diego marsh-elder and white rabbittobacco or any other special-status plant species. Prior to initiation of Project activities, a qualified biologist (i.e., a person having at minimum a BS or BA in wildlife management, ecology, zoology, botany, biology, or other closely related field, and at least 2 years’ experience conducting field investigations in San Diego County) approved by the City of Santee shall conduct a pre-construction presence/absence survey for special-status plants within the impact footprint and flag any specialstatus plants, including the known locations of San Diego marsh-elder and white rabbit-tobacco. If surveys are conducted pursuant to the FEMA Programmatic Biological Opinion for federally listed plant species, the qualified biologist shall be approved by the Carlsbad Fish and Wildlife Office (CFWO) in accordance with Gen AMM 16. If a special-status plant is observed, the biological monitor shall delineate an appropriate buffer zone (a minimum of 10 feet) depending on the sensitivity of the resource and the nature of the activity being conducted. Project activities shall completely avoid impacts to any special-status plant species.

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Delineation of Environmentally Sensitive Areas
▪ Prior to Project implementation, highly visible barriers (such as orange construction fencing, stakes, or flagging depending on the size of the treatment area and the sensitivity and proximity of the biological resources) shall be installed to designate environmentally sensitive areas (e.g., special-status plant locations, nesting birds, etc.) to be protected from vegetation management related activities. Environmentally sensitive areas to be avoided shall be identified during the preconstruction surveys described in MM BIO-1 and MM BIO-3 and implemented by a qualified biologist approved by the City of Santee. No Project activity of any type shall be permitted within these environmentally sensitive areas (with exceptions for removal of dead/decaying and nonnative species within jurisdictional aquatic resource areas in Zone 3). In addition, heavy equipment, including motor vehicles, shall not be allowed to operate within the environmentally sensitive areas. All vegetation management equipment shall be operated in a manner so as to prevent accidental damage to environmentally sensitive areas and associated barriers. No structure of any kind, equipment staging, incidental storage of equipment or supplies, or access roads shall be allowed within these protected zones. Silt fence barriers shall be installed, as appropriate, at the environmentally sensitive area boundary to prevent accidental deposition of fill material or sediment runoff into areas where sensitive biological features are adjacent to treatment areas. Flagging and/or fencing shall be removed upon completion of the activities.

Invasive Species Control
▪ Invasive exotic plant species shall be removed from the Project work area and controlled during vegetation management periods. Project measures shall be included to ensure invasive plant material is not spread from the Project Site to other areas by disposal off site or by tracking seed on equipment, clothing, and shoes. Equipment/material imported from an area of invasive plants must be identified and measures implemented to prevent importation and spreading of non-native plant material within the Project Site. Disposal of the plant debris shall follow the regulations set by the County of San Diego agriculture commissioner. All vegetation management equipment shall be cleaned to remove dirt, seeds, vegetative material, or other debris that could contain or hold seeds of noxious weeds before arriving to and leaving from the Project Site. Eradication strategies (i.e., exotic plant abatement programs) shall be employed should an invasion occur during vegetation management activities.

Trash Control
▪ To avoid attracting predators of Covered Species and other special-status species, the Project Site shall be kept clean of debris. All food-related trash items shall be enclosed in sealed containers and regularly removed from the site(s) daily.

On-Site Training and Monitoring
▪ All personnel involved in the on-site Project activities shall be required to participate in a preactivity training and education program administered by the City, or their designee, to understand the avoidance and minimization obligations of the Project. ▪ The City shall require that a qualified biologist monitor Project activities for the duration of the Project to ensure that measures are being employed to avoid incidental disturbance of habitat,

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species of concern, and other sensitive biological resources. The biological monitor shall notify the City immediately of any non-compliance, and the City shall make an assessment that generates appropriate measures for the contractor to implement for remediation.

Water Quality Best Management Practices
▪ The vegetation treatment contractors shall implement BMPs to protect water quality. To minimize soil disturbance, the vegetation treatment contractors shall leave stumps from removed trees and shrubs intact, with stump heights not exceeding 6 inches, as measured from the uphill side as described in the Fuels Treatment Plan (City of Santee 2026). ▪ Actions to prevent sediment or debris from entering watercourses, aquatic areas, wetlands, and riparian areas during and after Project activities may include, but are not limited to, the following BMPs: silt fencing, fiber rolls and other erosion control blankets, gravel bag berms, sand bag barriers, tracking controls, stockpile management, dry season scheduling, preservation of existing vegetation, temporary soil stabilization, and dust and erosion control. ▪ No site personnel shall discharge solid or liquid materials into jurisdictional water features, wetland or riparian areas, or other sensitive habitats. Service and refueling of equipment shall only occur in areas that will not allow grease, oil, fuel, or other hazardous materials to pass into streams or retained vegetation. If discharged materials are observed during work activities, the biological monitor shall notify the City and appropriate entities immediately, including but not limited to applicable jurisdictional City or County, U.S. Fish and Wildlife Service, U.S. Army Corps of Engineers, California Department of Fish and Wildlife, and/or Regional Water Quality Control Board, and the City shall make an assessment that generates appropriate measures for the contractor to implement for remediation. Spills shall be cleaned up immediately and contaminated soils removed to approved disposal areas.

MM BIO-3 Biological Monitor. A qualified biological monitor (i.e., a person having at minimum a BS or BA in wildlife management, ecology, zoology, botany, biology, or other closely related field, and at least 2 years’ experience conducting field investigations in San Diego County) approved by the City of Santee shall be present to conduct a pre-activity sweep (i.e., pre-construction survey) of the work area prior to the commencement of work activities. Where monitoring is required pursuant to the FEMA Programmatic Biological Opinion for federally listed species, monitoring shall be conducted by or under the supervision of a CFWO-approved biologist in accordance with Gen AMM 16. The qualified monitor shall remain present during any Project activities in Zones 1 to 3 that occur in sensitive vegetation communities, as defined herein), to ensure no sensitive biological resources (i.e., sensitive vegetation communities, special-status species, and jurisdictional aquatic resources) are being adversely impacted from Project implementation in Zone 3 and that no special-status species or nesting birds are being adversely impacted from Project implementation in Zones 1 and 2. If a sensitive biological resource is observed during Project activities or during pre-construction surveys, the biological monitor shall delineate an appropriate buffer zone (a minimum of 10 feet) depending on the sensitivity of the resource and the nature of the activity being conducted.

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then prior to the use of temporary noise abatement, a qualified biologist shall confirm and verify with the City that the placement of the barriers are not located within any environmentally sensitive areas (e.g., special-status plant locations, sensitive vegetation communities, or jurisdictional aquatic resources) and would not impact any wildlife species or their movement.

MM BIO-4 Sensitive Vegetation Communities. Unintended impacts (i.e. sensitive vegetation removal) to sensitive natural communities occurring from thinning or trimming activities in Zones 1 and 2 would be remedied through restoration of the affected area. This would entail restoring the disturbed area to pre-project or ecologically improved conditions typically within one year of completing activities. A restoration plan will be prepared for and approved by the City , and depending on the area affected any other appropriate regulatory agency (i.e. USFWS, CDFW, USACE, and/or RWQCB), that includes: details for the restoration activities, a description of how the proposal provides offsets for the temporal loss, success criteria and the timeline for restoration. If habitat is unable to be restored, or the restoration does not meet the success criteria, the impacts would be considered permanent and would require mitigation consistent with the ratios identified in Table 1 below. This mitigation would entail a mitigation plan outlining the enhancement or restoration of habitat within City Owned Preserve Lands or through acquisition of a conservation easement within the Upland Standards Areas or San Diego River Subunit depending on the type of habitat being impacted so that impacts will be mitigated in-kind. The mitigation plan shall include at a minimum: details for the mitigation activities including the target function and services for the native plant communities established, mitigation work plan, performance standards, funding mechanism, and the timeline for completion of the mitigation program. The mitigation site would be included in the Managed Preserve and managed and monitored in perpetuity with funding for long-term management and monitoring provided through a non-wasting endowment.

Mitigation Ratios for Permanent Unintended Impacts
Vegetation Type a Habitat Criteria Mitigation Ratio
Riparian Forest/
Woodland
All riparian forest, including oak riparian 3:1
Riparian Scrub Drainages with riparian scrub 3:1
Freshwater Marsh,
Freshwater Seep,
Disturbed Wetlands,
Natural Channel, Open
Water e
Absence of native species or small (<0.25 acre)
amount of habitat
2:1 f
Presence of native species or large (>0.25 acre)
amount of habitat
3:1
Vernal Pools b Natural Vernal Pool 4:1
Man-made vernal pools with indicator plant species 3:1
Man-made pools with covered wildlife species 3:1
Oak Woodland Oak woodland containing any Engelmann oaks 3:1 Individual Oaks Trees with at least on trunk of 6” or more Dbh c or multi-trunked native oaks with aggregate diameter of
10” of more.
10:1 by tree
Coastal Sage Scrub
Coastal Sage/
Chaparral Scrub
Habitat small, isolated patches <1 acres 2:1
Habitat patches >1 acre 3:1

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Mitigation Ratios for Permanent Unintended Impacts
Vegetation Type a Habitat Criteria Mitigation Ratio
Chaparral All 2:1
Native Grassland All 3:1
Non-native grassland All 1:1
Disturbed lands,
Eucalyptus, agricultural
lands d
No known habitat value for Covered Species None
Habitat value for or presence of burrowing owls 1:1 as appropriate to ensure like value
Notes:
a Vegetation types based on the Holland Vegetation classification system. See Appendix E, Vegetation Communities Descriptions.

All other natural habitat types not listed in this table have a 1:1 mitigation ratio requirement. b Vernal pool mitigation must meet a ‘no net loss’ criteria through creation of new vernal pool habitat and/or restoration or enhancement of existing vernal pool habitat. Preservation of existing vernal pool alone does not provide mitigation credits. If an existing vernal pool is significantly disturbed, enhancement of the existing pool can be implemented to provide up to a 1:1 mitigation credits towards the total requirement.
c Dbh = Diameter at Breast Height. Tree diameter is measured at 4 ½ feet above ground level. This measure is known as diameter at breast height or DBH. Diameter can be measured with diameter tape d Disturbed land may include agricultural lands, ruderal, eucalyptus, and previously authorized graded areas. e Any impacts to open water areas within abandoned sand mining pits along the San Diego River should be mitigated with creation of riparian scrub or riparian woodland, as these open water areas are unnatural, are relatively common, and these same areas likely supported riparian areas before mining occurred. f Different ratios may be required under separate regulatory programs under the Clean Water Act, the Porter-Cologne Water Quality Control Act, and Section 1600 et seq. of the Fish and Game Code.

MM BIO-5 Avoidance of Listed Species Take: Least Bell’s Vireo. All riparian habitat tree trimming or thinning within Zones 1 and 2 and invasive species removal in Zone 3 shall occur outside the least Bell’s vireo breeding season (April 1 through August 151). If that is not possible then no vegetation management activities shall occur during the least Bell’s vireo breeding season until the following requirements have been met:

If presence of least Bell’s vireo is determined or assumed to occur on the Project Site, the following measures shall be required to be implemented:
a. No vegetation removal shall occur within occupied habitat during the least Bell’s vireo breeding season (April 1 to August 15) or until the nest has shown to be vacated. A 500- foot buffer shall be required around the nest site. If 100% avoidance of occupied habitat is not feasible, consultation with USFWS and California Department of Fish and Wildlife (CDFW) shall be initiated prior to implementation of any activities that may impact occupied habitat, directly or indirectly.

MM BIO-6 Avoidance of Listed Species Take: Coastal California Gnatcatcher. To the maximum extent feasible, staging areas, equipment storage areas, and access routes shall be located outside coastal sage scrub, alluvial fan scrub, and other suitable coastal California gnatcatcher habitat and shall utilize existing disturbed areas and roads whenever practicable. 1 Unitt and Klovstad (2004) states that the nesting season generally lasts from April to July and dates for fledglings ranged between 27 April to 21 August.

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All coastal sage scrub thinning shall occur outside the coastal California gnatcatcher breeding season (March 15 through August 15). If that is not possible then no vegetation management activities shall occur during the coastal California gnatcatcher breeding season (February 15 through August 15) until the following requirements have been met:

1. A permitted biologist (i.e., possessing a valid Endangered Species Act Section 10(a)(1)(a) Recovery Permit) shall conduct a focused protocol-level survey (i.e., three visit survey) for coastal California gnatcatcher (Polioptila californica californica) using the most recent protocol (U.S. Fish and Wildlife Service [USFWS] 1997 Coastal California Gnatcatcher Presence/Absence Survey Guidelines) 3 days prior to Project activities within all fuel reduction areas containing coastal sage scrub including a 500-foot buffer. If presence of coastal California gnatcatcher is determined or assumed to occur on the Project Site, the following measures shall be required to be implemented by the applicant:
a. No vegetation trimming or thinning shall occur within occupied habitat during the coastal California gnatcatcher breeding season (February 15 to August 15). A minimum 500-foot buffer shall be established around occupied nests unless a larger buffer is determined necessary by the permitted biologist based on species behavior, topography, existing disturbance conditions, or other site-specific factors. b. TheA 500-foot buffer shall be required around the nest site until it is shown to be vacated. If 100% avoidance of occupied habitat is not feasible, consultation with USFWS and California Department of Fish and Wildlife (CDFW) shall be initiated prior to implementation of any activities that may impact occupied habitat, directly or indirectly. c. Other measures from FWS-CFWO-16B0293-18F1358; Section 7 Consultation on FEMA Disaster, Mitigation and Preparedness Programs in Imperial, Inyo, Kern, Los Angeles, Orange, Riverside, San Bernardino, and San Diego Counties, California Coastal California Gnatcatcher CAGN-1 through CAGN-4 will apply. CAGN-5 through CAGN-7 do not apply as this project is intended to enhance native habitat and species.

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Agencies (i.e., U.S. Fish and Wildlife Service and California Department of Fish and Wildlife) for review prior to discontinuing the noise limits and nest buffers. The nest buffer area shall be demarcated in the field with flagging and stakes or construction fencing. Personnel, including all contractors working on site, are required to be instructed on the sensitivity of the area.

No Project activities shall encroach into established buffers without the consent of a monitoring biologist. The buffer shall remain in place until it is determined that the nestlings have fledged and the nest is no longer active. Work can proceed into the buffer when the qualified biologist has determined that the nest is no longer active or if appropriate noise mitigation is in place.

MM BIO-8 Avoidance of Listed Species Take: Crotch’s Bumblebee. A pre-construction survey shall be conducted by a qualified biologist with expertise in surveying for bumble bees no more than 5 days prior to any Project activities occurring within Zones 1, 2, or 3. If a Crotch’s bumble bee nest is detected during the pre-construction survey, the Project’s biological monitor shall establish, monitor, and maintain a no-work buffer around the nest. The size and configuration of the nowork buffer shall be based on best professional judgment of the Project biologist in consultation with the Wildlife Agencies. The buffer shall provide at least 50 feet of clearance around nest entrances. Project activities shall not occur within the no-work buffer until the colony is no longer active. To determine that a nest is no longer active, the nest shall be observed for a minimum of 60 minutes each day across a minimum of 3 days during suitable flight weather (i.e., ambient air temperature between 60° and 90° degrees F, winds under 10 mph, and no precipitation higher than a drizzling rain). If no bees are seen flying in or out of the nest by the end of the observation period, it shall be determined that the nest is no longer active. If Project activities occur outside of the colony active period (April 1–August 31), then pre-construction surveys for active bee nest colonies are not required.

MM BIO-9 Tree Survey. Prior to the commencement of vegetation management activities within Zones 1 to 3, a Certified Arborist shall be present to conduct a comprehensive tree inventory to determine the exact locations for dead, dying, and invasive species slated for removal. The comprehensive tree inventory may also occur concurrently with vegetation management activities so as not to interfere with Project timing. Trees shall be marked or flagged by the Certified Arborist for the contractor and the tree inventory and removal tracking shall be provided to the City of Santee.

MM BIO-10 Jurisdictional Aquatic Resources Permitting. The City of Santee shall obtain the applicable permits for treatment activities (i.e., trimming or thinning of native or non-native vegetation within Zones 1 and 2) occurring within jurisdictional aquatic resources, such as a Section 404 permit from USACE, a Streambed Alteration Agreement from CDFW, and a 401 Water Quality Certification/Waste Discharge Requirement from the RWQCB. No native or non-native vegetation trimming or thinning in Zones 1 and 2 shall occur within any jurisdictional riparian/wetland vegetation communities on the Project Site prior to issuance of aquatic resources permits.

MM BIO-11 Jurisdictional Aquatic Resources Avoidance. Vegetation management activities occurring within Zone 3 shall only involve treatment or removal of dead, dying, or invasive species. The Project shall

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commit to avoid impacting streams within Zones 1, 2, and 3 by crossing them using temporary rubber mats or pads to distribute weight and minimize vegetation trampling and soil disturbance, and helicopter and/or crane removal where equipment access is constrained and hand carry is infeasible.

Level of Significance After Mitigation
A. 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? Direct impacts to special-status plants located in Zones 1 to 3 would be avoided through implementation of MM BIO-1, and impacts to special-status plant species would be less than significant.

Indirect impacts to special-status plants related to decreased water quality and altered hydrology, soil compaction, elevated dust levels, and the spread of invasive plant species would be reduced to below significance through implementation of MM BIO-1, MM BIO-2, and MM BIO-3.Indirect impacts to specialstatus plants would be less than significant.

Direct impacts to individual special-status wildlife species would be reduced to below significance through implementation of MM BIO-3 that would ensure no special-status species would be injured or harmed during Project activities. Direct impacts to sensitive vegetation communities that support special-status species would be reduced to below significance through the implementation of MM BIO-4 mitigation for unintended impacts to riparian habitat and coastal sage scrub habitat within Zones 1 and 2. Thus, direct impacts to sensitive vegetation would be less than significant.

Impacts to nesting habitat for special-status avian species and other nesting and migratory birds and raptors during the nesting bird breeding season would be reduced to below significance through implementation of MM BIO-5, MM BIO-6, and MM BIO-7 that would ensure impacts to nesting habitat would only occur outside the nesting bird breeding season (February 15 through September 30). Implementation of MM BIO-3 would also reduce potentially adverse impacts to nesting birds by requiring a biological monitor be present to establish nest buffers if Project activities cannot avoid the avian nesting season. Thus, direct impacts to nesting and migratory birds would be less than significant.

Indirect impacts to special-status wildlife, including nesting birds, due to decreased water quality and altered hydrology, soil compaction, elevated dust levels, and the spread of invasive plant species would be avoided through implementation of MM BIO-2 and MM BIO-3. Indirect impacts to special-status wildlife species would be less than significant.

Fish and Wildlife Service?
Direct Impacts to sensitive vegetation communities in Zones 1 and 2 would be reduced to below significance through implementation of MM BIO-4 that would require compensatory mitigation. MM BIO-3 that would require a biological monitor be present to ensure treatment and vegetation removal activities occur only within the designated areas and no unauthorized impacts to sensitive vegetation communities occur would further reduce impacts to sensitive vegetation. Direct impacts to trees within Zone 3 would be

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reduced through implementation of MM BIO-9 that would require comprehensive mapping of tree species to be removed. Direct impacts to sensitive vegetation communities would be less than significant.

Indirect impacts to sensitive vegetation communities in Zones 1 to 3 through decreased water quality and altered hydrology, soil compaction, elevated dust levels, and the spread of invasive plant species. would be avoided through implementation of MM BIO-2 and MM BIO-3. Indirect impacts to sensitive vegetation communities would be less than significant.

C. 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? Direct impacts within Zones 1 and 2 from native brush thinning would be reduced to below significance through implementation of MM BIO-10 that would require permitting from the appropriate resource agencies (i.e., USACE, RWQCB, and CDFW). In addition, a biological monitor shall be present in accordance with MM BIO-3 to ensure treatment and vegetation removal activities occur in accordance with the Project’s aquatic resource permits, and there are no direct impacts occurring outside the designated areas. Direct impacts to jurisdictional aquatic resources within Zones 1 and 2 would be less than significant.

No direct impacts to potentially jurisdictional resources in Zone 3 are anticipated from Project implementation. However, implementation of MM BIO-11 that would ensure activities occurring in Zone 3 would only involve removal of dead, dying, or invasive species utilizing methods that would not adversely impact aquatic resources. A biological monitor shall also be present in accordance with MM BIO-3 to ensure treatment and vegetation removal activities do not impact any aquatic resource areas located within Zone 3. Direct impacts to protected jurisdictional aquatic resources would be less than significant.

Indirect impacts to jurisdictional aquatic resources through decreased water quality and altered hydrology, soil compaction, elevated dust levels, and the spread of invasive plant species would be avoided through implementation of MM BIO-2 and MM BIO-3. Indirect impacts to jurisdictional aquatic resources would be less than significant.

D. 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?
Impacts to wildlife corridors and nursery sites are considered less than significant. No mitigation is required.

E. Would the Project conflict with any local policies or ordinances protecting biological resources, such as a tree preservation policy or ordinance?
Impacts related to conflict with local policies and ordinances would be less than significant. No mitigation is required.

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F. 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? Project implementation would not conflict with the provisions of the San Diego County MSCP or Draft Santee MSCP Subarea Plan, nor would it prevent the Draft Santee MSCP Subarea Plan from being approved or compromise continued implementation of the MSCP in San Diego County. Impacts are less than significant, and no mitigation is required.

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4.2 Cultural and Tribal Cultural Resources
This section describes the existing cultural (archaeological and built environment), and tribal cultural resources conditions of the San Diego River Fire Hazard Mitigation Program: Fuels Treatment Plan (Project) Site, identifies associated regulatory requirements, evaluates potential impacts, and identifies mitigation measures, if needed to reduce or avoid significant impacts, related to implementation of the Project.

The following analysis is based, in part, on the following sources:
▪ Recommended Cultural Area of Potential Effects for the San Diego River Fire Hazard Mitigation Plan Phase I, prepared by Dudek in April 2026 (Appendix C)
▪ Cultural Resource Assessment Report, prepared by Dudek in January July 2026 (Appendix D)

4.2.1 Existing Conditions

4.2.1.1 Study Area
The Project Site encompasses an approximately 300‑acre segment of the San Diego River corridor within the City of Santee. The Project Site and surrounding suburbs are generally flat, with the San Diego River running east– west through the center between wetland, riparian, and disturbed vegetation. Elevations range from approximately 310 to 360 feet above mean sea level. Vegetation within the Project Area of Potential Effect (APE) and surrounding vicinity is characterized by a mix of native as well as non-native vegetation communities and land cover types.

Walking paths, open‑space trails, and vegetation are distributed throughout the corridor, with the Walker Preserve Trail located toward the eastern extent of the Project Site. Portions of the river channel and adjacent terraces are seasonally inundated or densely vegetated, while other areas exhibit evidence of prior disturbance, grading, and recreational access.

Historical topographic maps (1893 to 1941) and early aerial imagery (1953 to 1964) indicate that the Project Site primarily consisted of open space within the San Diego River corridor, including undeveloped floodplain, riparian habitat, and lands historically used for agriculture. Over time, the surrounding landscape experienced substantial transformation, as residential subdivisions, commercial development, and municipal facilities expanded around the river. Continued remodeling of existing structures, infrastructure improvements, and the introduction of newer and larger developments further altered the character of the area. Commercial and industrial uses have also proliferated south of the river corridor as suburban growth progressed. Overall, development adjacent to the Project Site reflects predominantly modern, utilitarian building forms typical of suburban San Diego County, while the Project Site itself retains a largely natural riverine character defined by riparian and wetland vegetation communities (Appendix D).

4.2.1.2 Historic Setting
Historical Overview of the City of Santee
The City of Santee is located in eastern San Diego County. As described in Appendix D, the area was called several different names before it became known as “Santee” in 1893. Originally, the land was inhabited by the Kumeyaay

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tribe of Native Americans who resided on the banks of the San Diego River in the village of “Sinyeweche” (the present-day area of “Santee”). The Kumeyaay dominated the land until the arrival of the Spanish in 1779. At the direction of Father Junipero Serra, the Kumeyaay constructed the Old Mission Dam for the nearby Mission de Alcala.

During this period, the land was divided among the Spanish soldiers as payment for their services, and the Native Americans were gathered to live at the Mission. In 1822, the Mission system was disbanded by the Mexican government and during the 1840s, American settlers arrived in California.

In 1870, George A. Cowles migrated to California from Florida. In 1877, he purchased 4,000 acres of land in the Santee area, in which he planted vineyards, pomegranate and magnolia trees. At this time, the Cuyamaca Railroad ran through the area and the local station became known as “Cowles Station” due to its proximity to the vineyard and orchards owned by Cowles. The surrounding area soon became known as “Cowleston.” After the death of George Cowles death in 1887, his wife, Jennie, married realtor and surveyor, Milton Santee.

Several years later, Jennie Cowles Santee named the early post office “Santee,” and by 1893, the town name was changed to Santee. Similarly, the Cowles School, established in 1891, and the Cowles School District subsequently changed their names to Santee as well.

In 1885, Hosmer P. McKoon purchased 9,543 acres of land in the Santee area for his “Fanita Ranch” (named after his wife, Fannie). However, over the next few years McKoon sold segments of the ranch to new arrivals, including 7,000 acres to the Scripps family in 1898. The Scripps used the ranch to raise cattle and built a country resort for their family. Like much of the rest of San Diego County during this period, Santee’s economy was based in agriculture and ranching. Farms, such as the Edgemoor Stock Farm (established in 1908), drove the local economy and contributed to the city’s rural identity. In 1914, the opening of the Panama Canal resulted in an increase in shipping ports in San Diego County that led to more growth in the surrounding areas. However, little growth came to San Diego during the early twentieth century.

In 1941, the United States’ entry into the Second World War increased military activity on the West Coast and brought new development to Santee during the 1940s. The federal government used 2,300 acres of the Fanita Ranch as military training grounds, and the Marine Corps Base, Camp Pendleton, was established north of Santee.

The wartime demand for manufacturing transformed San Diego County’s industry and it became home to various aircraft and ship manufacturing as well as military training.

During the mid-twentieth century, Santee’s economy increased, and the city became home to a variety of industries.

After the war, Santee’s agricultural industry significantly decreased, and it began to suburbanize. Residential development in the area was built for military and worker housing during World War II, and the population rapidly increased. In 1967, the Las Colinas Detention Facility opened as a juvenile facility, and in 1979, it was converted to an adult women’s institution to serve as the primary facility for women prisoners in San Diego County. The establishment of the detention center introduced employment opportunities in the local area and served as a catalyst for further population growth. Such rapid growth created concern about the character of the community, so Santee residents created the San Diego County Santee Citizen’s Planning Committee. The committee was officially recognized by the San Diego County Board of Supervisors in December 1968, and it has continued to serve as a local land-use and planning advisory board to the county planning commission and the Board of Supervisors.

In 1974, the Committee secured approval of the Santee Community Plan which acted as the area’s General Plan until the Santee General Plan was adopted in 1984. In 1980, the citizens of Santee voted to incorporate in order to gain local control over the development of their city, and the creation of the General Plan was their first goal.

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Santee’s rapid population increase resulted in the need for more recreation and entertainment services. In 1974, two regional parks were established in the city: Mission Trails Regional Park and Santee Lakes Regional Park.

Additionally, more commercial development and entertainment venues followed. During the late twenty-first century, much of Santee’s economy has focused upon the hospitality and entertainment sectors, as well as health care assistance, retail trade, and educational services. Since the 1980s, the City has continued to grow, reaching a population of approximately 54,000 residents in 2020. Since this time, Santee has worked toward protecting and enhancing the San Diego River, expanded its park system, and boasts major commercial centers.

4.2.1.3 Cultural Resources
This section presents information gathered during the cultural resources inventory efforts in support of the Project (see Appendix D for additional details). Section 4.2.2, Relevant Plans, Policies, and Ordinances, provides background information on the federal, state, and local regulations and requirements related to these resources.

Previously Conducted Cultural Resources Studies
The South Coastal Information Center records indicate that between 1973 and 2021, 185 previous cultural resources technical investigations have been conducted within 1 mile of the Project Site (Appendix D). Of these 185 studies, 43 previous studies overlap portions of the Project Site. A total of 14 of the cultural studies are considered relevant to the Project because they contain information pertaining to the previously recorded cultural sites within the Project Site. The 14 studies conducted within the Project Site previously consist of six archaeological survey reports, one archaeological monitoring report, four extended Phase I and Phase II testing and evaluation studies, one supplemental historic property survey, one environmental report with a cultural resources component, and one data recovery program.

Previously Recorded Cultural Resources
The South Coastal Information Center records search identified 79 cultural resources within a 1-mile radius of the Project Site. Of the 79 resources identified within the 1-mile radius, 3 resources were identified within the Project Site. These three sites include a bedrock milling site with associated artifact scatter, a habitation site deposit including fire affected rock, lithic and ceramic artifacts, and midden soil, and a lithic scatter.

Archival Research
In addition to the South Coastal Information Center records search, Dudek conducted a review of topographic (topo) maps, and historical aerial photographs to understand the development of the Project Site and surrounding properties over time. The review identified changes to the San Diego River Corridor, surrounding development, and land alterations.

Historic topo maps of the Project Site are available from 1893 to 2021 (NETR 2025). The historic topo maps depict the San Diego River flowing through the Project Site during the earliest mapped years, with no discernible large structures present within the Project Site between 1893 and 1941. Surrounding lands remain largely undeveloped throughout this early period. By 1942, Fanita Ranch appears within the southwestern portion of the Project Site, and by 1947, structures associated with “Edgemoore County Farms” are shown adjacent to North Magnolia Avenue.

Through 1955, the Project Site itself shows no major visible changes, although a sand pit and several small structures are mapped near Cuyamaca Street in 1956. The 1959 and 1964 maps also show no major modifications within the Project Site, but by 1969, several sand pits are mapped within or very near the Project Site. Subsequent

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mapping from 1975 to 1986 continues to show no substantial change within the Project Site, while the 2001 topographic map depicts an athletic field just north of the Project Site. More recent maps from 2012 and 2015 reflect increased urban development through a greater number of named streets surrounding the Project Site, and by 2018 and 2021 the Walker Preserve Trail is mapped within the eastern portion of the Project Site.

Historical aerial photographs (historic aerials) of the Project Site are available from 1953 to 2022 and provide more detail on the historic development of the subject property and surrounding properties through time (NETR 2025).

The earliest historical aerial from 1953 shows no major structures within the Project Site, though several north and south trending roads cross the corridor. By 1964, development is present in the northern portion of the Project Site near present-day Chubb Lane, and agricultural activity is visible in that vicinity. Residential development is evident to the north and south of the Project Site by 1966, and agricultural development appears to the east by 1968. A 1971 aerial shows the San Diego River dammed within part of the Project Site. Aerials from 1978 through the late 1980s show expanded residential and commercial development north and south of the river, with the Carlton Oaks Golf Course appearing west of the Project Site by 1989. From 1990 through 2003, no significant changes are visible within the Project Site. By 2005 and 2009, new development is apparent northeast of the Project Site near the present-day Lakeside Sports Park, along with several hiking trails in the northeast portion of the Project Site. Aerial photographs from 2010 through 2022 show no major changes within the Project Site.

Cultural Resources Pedestrian Survey
Dudek archaeologists and Red Tail Environmental Native American Monitor conducted an intensive- level pedestrian survey of the Project Site December 8 to December 10, 2025, and on January 9, 2026. Densely vegetated areas and large bodies of water were not subject to pedestrian survey, as these locations present safety concerns for survey personnel and offer low potential for observable cultural materials.

The cultural resources pedestrian survey resulted in the identification of nine cultural resources within the Project Site, including three previously recorded archaeological sites, three newly recorded archaeological sites and six three newly recorded isolated finds. The three previously recorded archaeological sites include, CA‑SDI‑005050, a prehistoric habitation site containing midden soil, bedrock milling features, and associated artifacts; CA‑SDI‑010148, a large prehistoric archaeological site containing fire‑affected rock, lithic and ceramic artifacts, and midden deposits; and CA-SDI-021860, a light lithic scatter. The three newly identified archaeologist sites includeand SDRFM-DF-S-001, a historic period linear rock feature with a small historic period refuse concentration; SDRFM-DF-S-002, a historic period site consisting of a foundation pad and concrete footing; and SDRFM-DF-S‑003, a newly identified prehistoric milling feature consisting of a bedrock mortar. The six three isolated finds (SDRFMDF-I-001, SDRFM-DF-I-002, and SDRFM-DF-I-003) consist of individual flakes and isolated ground stone fragments that do not meet criteria for site designation.

Native American Coordination
Native American Heritage Commission Sacred Lands File Search Dudek requested a Native American Heritage Commission (NAHC) search of the Sacred Lands File (SLF) for the Project Site on December 11, 2025. The SLF consists of a database of known Native American resources. A response letter was received via email from the NAHC on December 10, 2025, stating resources are listed in the SLF for this area, but did not provide details on what the resource(s) are or where they are located. Dudek sent outreach letters to 17 Native American groups and individuals on December 29, 2025. To date, no responses have been received. Any future responses would be included in subsequent versions of this report. To date, two

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responses have been received. On January 30, 2026, Jason Santos, the Deputy Tribal Historic Preservation Officer from the Manzanita Band of Kumeyaay Nation, responded by stating that the Project APE is not within the boundaries recognized by the Manzanita Indian Reservation. However, Mr. Santos stated that the Project APE is within the boundaries that Manzanita considers its Traditional Use Area. The Manzanita Band, therefore, has requested to kept informed as the Project progresses. Mr. Santos also recommended archaeological and Tribal cultural monitoring for all ground disturbing activities near known archaeological sites. Further, on February 20, 2026, Mr. Jason Lavigne, the Tribal Historic Preservation Officer from the San Pasqual Tribe of Mission Indians, responded by stating that the San Pasqual Tribe does not have any comments on the proposed Project. Mr. Lavigne also added that San Pasqual reserves the right to provide further comments if additional information on the Project becomes available, or if the circumstances change.

Assembly Bill 52 Consultation
The Project is subject to compliance with Assembly Bill (AB) 52 (California Public Resources Code [PRC] Section 21074), which requires consideration of impacts to tribal cultural resources (TCRs) as part of the California Environmental Quality Act (CEQA) process and requires the lead agency to notify any tribal groups (who have requested notification) of the proposed Project. The City sent AB 52 letters on March 20, 2026, and no responses were received.

4.2.2 Relevant Plans, Policies, and Ordinances
Federal
Section 106 National Historic Preservation Act
Federal protection of cultural resources is legislated by (a) the National Historic Preservation Act of 1966 as amended by 16 U.S. Code 470, (b) the Archaeological Resource Protection Act of 1979, and (c) the Advisory Council on Historical Preservation. These laws and organizations maintain processes for determination of the effects on historical properties eligible for listing in the National Register of Historic Places (NRHP).

Section 106 of the National Historic Preservation Act and accompanying regulations (36 CFR Part 800) constitute the main federal regulatory framework guiding cultural resources investigations and requires consideration of effects on properties that are listed in or may be eligible for listing in the NRHP. The NRHP is the nation’s master inventory of known historic resources. It is administered by the National Park Service and includes listings of buildings, structures, sites, objects, and districts that possess historic, architectural, engineering, archaeological, and cultural districts that are considered significant at the national, state, or local level. ▪ The formal criteria (36 CFR 60.4) for determining NRHP eligibility are as follows:
▪ The property is at least 50 years old (however, properties under 50 years of age that are of exceptional importance or are contributors to a district can also be included in the NRHP); ▪ It retains integrity of location, design, setting, materials, workmanship, feeling, and associations; and ▪ It possesses at least one of the following criteria:

Association with events that have made a significant contribution to the broad patterns of history (events).

Association with the lives of persons significant in the past (persons).

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Distinctive characteristics of a type, period, or method of construction, or represents the work of a master, or possesses high artistic values, or represents a significant, distinguishable entity whose components may lack individual distinction (architecture).

Has yielded, or may be likely to yield, information important to prehistory or history (information potential).

Listing in the NRHP does not entail specific protection or assistance for a property but it does guarantee recognition in planning for federal or federally assisted projects, eligibility for federal tax benefits, and qualification for federal historic preservation assistance. Additionally, project effects on properties listed in the NRHP must be evaluated under CEQA.

The National Register Bulletin also provides guidance in the evaluation of archaeological site significance. If a heritage property cannot be placed within a particular theme or time period, and thereby lacks “focus,” it is considered not eligible for the NRHP. In further expanding upon the generalized National Register criteria, evaluation standards for linear features (such as roads, trails, fence lines, railroads, ditches, flumes, etc.) are considered in terms of four related criteria that account for specific elements that define engineering and construction methods of linear features: (1) size and length; (2) presence of distinctive engineering features and associated properties; (3) structural integrity; and (4) setting. The highest probability for NRHP eligibility exists within the intact, longer segments, where multiple criteria coincide.

State
California Register of Historical Resources (Public Resources Code Section 5020 et seq.) In California, 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” (PRC Section 5020.1[j]). In 1992, the California legislature established the California Register of Historic 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]). The criteria for listing resources on the CRHR were expressly developed to be in accordance with previously established criteria developed for listing in the NRHP, enumerated below.

According to PRC Section 5024.1(c)(1–4), a resource is considered historically significant if it (i) retains “substantial integrity,” and (ii) meets at least one of the following criteria:

1. Is associated with events that have made a significant contribution to the broad patterns of California’s history and cultural heritage.

2. Is associated with the lives of persons important in our past.

3. 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.

4. Has yielded, or may be likely to yield, information important in prehistory or history.

In order to understand the historic importance of a resource, sufficient time must have passed to obtain a scholarly perspective on the events or individuals associated with the resource. A resource less than 50 years old may be considered for listing in the CRHR if it can be demonstrated that sufficient time has passed to understand its historical importance (see 14 CCR 4852[d][2]).

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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 NRHP, and properties listed or formally designated as eligible for listing in the NRHP are automatically listed in the CRHR, as are the state's landmarks and points of interest. The CRHR also includes properties designated under local ordinances or identified through local historical resource surveys.

Native American Historic Cultural Act (California Public Resources Code Section 5097 et seq.) The Native American Historic Resources Protection Act (PRC 5097 et seq.) 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 human remains or associated burial items are discovered during construction of a Project; and establishes the NAHC 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 a Native American historic or cultural site that is listed or may be eligible for listing in the CRHR.

California Native American Graves Protection and Repatriation Act The California Native American Graves Protection and Repatriation Act, enacted in 2001, requires 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 Native American Graves Protection and Repatriation Act also provides a process for the identification and repatriation of these items to the appropriate tribes.

California Environmental Quality Act
As described further below, the following CEQA statutes and CEQA Guidelines are of relevance to the analysis of archaeological, historic, and cultural resources:
▪ California Public Resources Code Section 21083.2(g) defines “unique archaeological resource.” ▪ California Public Resources Code Section 21084.1 and CEQA Guidelines Section 15064.5(a) define “historical resources.” In addition, CEQA Guidelines Section 15064.5(b) defines the phrase “substantial adverse change in the significance of an historical resource.” It also defines the circumstances when a project would materially impair the significance of an historical resource. ▪ California Public Resources Code Section 5097.98 and CEQA Guidelines Section 15064.5(e) set forth standards and steps to be employed following the accidental discovery of human remains in any location other than a dedicated ceremony.
▪ California Public Resources Code Sections 21083.2(b)-(c) and CEQA Guidelines Section 15126.4 provide information regarding the mitigation framework for archaeological and historic resources, including examples of preservation-in-place mitigation measures; preservation-in-place is the preferred manner of mitigating impacts to significant archaeological sites because it maintains the relationship between artifacts and the archaeological context and may also help avoid conflict with religious or cultural values of groups associated with the archaeological site(s).

More specifically, under CEQA, a project may have a significant effect on the environment if it may cause “a substantial adverse change in the significance of an historical resource” (PRC Section 21084.1; CEQA Guidelines Section 15064.5[b]). If a site is either listed or eligible for listing in the CRHR, or if it is included in a local register

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of historic resources or identified as significant in a historical resources survey (meeting the requirements of PRC Section 5024.1[q]), it is a “historical resource” and is presumed to be historically or culturally significant for purposes of CEQA (PRC Section 21084.1; CEQA Guidelines Section 15064.5[a]). The lead agency is not precluded from determining that a resource is a historical resource even if it does not fall within this presumption (PRC Section 21084.1; CEQA Guidelines Section 15064.5[a]).

A “substantial adverse change in the significance of an historical resource” reflecting a significant effect under CEQA means “physical demolition, destruction, relocation, or alteration of the resource or its immediate surroundings such that the significance of an historical resource would be materially impaired” (CEQA Guidelines Section 15064.5[b][1]; PRC Section 5020.1[q]). In turn, CEQA Guidelines Section 15064.5(b)(2) states the significance of an historical resource is materially impaired when a project incurs the following:

1. Demolishes or materially alters in an adverse manner those physical characteristics of an historical resource that convey its historical significance and that justify its inclusion in, or eligibility for, inclusion in the California Register of Historical Resources; or

2. Demolishes or materially alters in an adverse manner those physical characteristics that account for its inclusion in a local register of historical resources pursuant to section 5020.1(k) of the Public Resources Code or its identification in an historical resources survey meeting the requirements of section 5024.1(g) of the Public Resources Code, unless the public agency reviewing the effects of the project establishes by a preponderance of evidence that the resource is not historically or culturally significant; or

3. Demolishes or materially alters in an adverse manner those physical characteristics of a historical resource that convey its historical significance and that justify its eligibility for inclusion in the California Register of Historical Resources as determined by a lead agency for purposes of CEQA.

Pursuant to these sections, the CEQA inquiry begins with evaluating whether a Project Site contains any “historical resources,” then evaluates whether that project will cause a substantial adverse change in the significance of a historical resource such that the resource’s historical significance is materially impaired.

If it can be demonstrated that a project will cause damage to a unique archaeological resource, the lead agency may require reasonable efforts be made to permit any or all of these resources to be preserved in place or left in an undisturbed state. To the extent that they cannot be left undisturbed, mitigation measures are required (PRC Section 21083.2[a], [b], and [c]).

PRC Section 21083.2(g) defines a unique archaeological resource as an archaeological artifact, object, or site about which it can be clearly demonstrated that without merely adding to the current body of knowledge, there is a high probability that it meets any of the following criteria:

1. Contains information needed to answer important scientific research questions and that there is a demonstrable public interest in that information.

2. Has a special and particular quality such as being the oldest of its type or the best available example of its type.

3. Is directly associated with a scientifically recognized important prehistoric or historic event or person.

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Impacts to non-unique archaeological resources are generally not considered a significant environmental impact (PRC Section 21083.2[a]; CEQA Guidelines Section 15064.5[c][4]). However, if a non-unique archaeological resource qualifies as a TCR (PRC Section 21074[c], 21083.2[h]), further consideration of significant impacts is required.

CEQA Guidelines Section 15064.5 assigns special importance to human remains and specifies procedures to be used when Native American remains are discovered. These procedures are detailed in PRC Section 5097.98.

California Environmental Quality Act Guidelines Section Public Resources Code Section 21083.2(b)
Pursuant to these sections, CEQA first evaluates whether a Project Site contains any “historical resources,” then assesses whether that Project would cause an adverse effect to the significance of a historical resource.

When a Project significantly affects a unique archaeological resource, CEQA imposes special mitigation requirements. Specifically, “if it can be demonstrated that a Project will cause damage to a unique archaeological resource, the lead agency may require reasonable efforts to be made to permit any or all of these resources to be preserved in place or left in an undisturbed state. Examples of that treatment, in no order of preference, may include, but are not limited to, any of the following:

Planning construction to avoid archaeological sites.

Deeding archaeological sites into permanent conservation easements.

Capping or covering archaeological sites with a layer of soil before building on the sites.

Planning parks, greenspace, or other open space to incorporate archaeological sites.” California Public Resources Code, Section 21083.2(b)(1)–(4).

If these “preservation in place” options are not feasible, mitigation may be accomplished through data recovery (PRC Section 21083.2[d]; 14 CCR 15126.4[b][3][C]). PRC Section 21083.2(d) states that “excavation as mitigation shall be restricted to those parts of the unique archeological resource that would be damaged or destroyed by the Project. Excavation as mitigation shall not be required for a unique archeological resource if the lead agency determines that testing or studies already completed have adequately recovered the scientifically consequential information from and about the resource, if this determination is documented in the environmental impact report.” These same requirements are set forth in slightly greater detail in CEQA Guidelines Section 15126.4(b)(3), as follows:

Preservation in place is the preferred manner of mitigating impacts to archeological sites. Preservation in place maintains the relationship between artifacts and the archeological context. Preservation may also avoid conflict with religious or cultural values of groups associated with the site.

Preservation in place may be accomplished by, but is not limited to, the following:

1. Planning construction to avoid archeological sites;

2. Incorporation of sites within parks, greenspace, or other open space;

3. Covering the archeological sites with a layer of chemically stable soil before building tennis courts, parking lots, or similar facilities on the site[; and]

4. Deeding the site into a permanent conservation easement.

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When data recovery through excavation is the only feasible mitigation, a data recovery plan, which makes provision for adequately recovering the scientifically consequential information from and about the historical resource, shall be prepared and adopted prior to any excavation being undertaken.

Note that, when conducting data recovery, “if an artifact must be removed during Project excavation or testing, curation may be an appropriate mitigation.” (Ibid.) However, “data recovery shall not be required for an historical resource if the lead agency determines that testing or studies already completed have adequately recovered the scientifically consequential information from and about the archeological or historic resource, provided that determination is documented in the EIR and that the studies are deposited with the California Historical Resources Regional Information Center” (14 CCR 15126.4[b][3][D]).

California Health and Safety Code
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. California 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 reasonably suspected to contain human remains shall occur until the county coroner has examined the remains (Section 7050.5b). PRC Section 5097.98 also outlines the process to be followed in the event that remains are discovered. 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 (Section 7050.5c). The NAHC would notify the most likely descendant (MLD). With the permission of the landowner, the MLD may inspect the site of discovery. The inspection must be completed within 48 hours of being granted access to the site. The MLD may recommend means of treating or disposing of, with appropriate dignity, the human remains and items associated with Native Americans.

California State Assembly Bill 52
AB 52 of 2014 amended PRC Section 5097.94 and added PRC Sections 21073, 21074, 21080.3.1, 21080.3.2, 21082.3, 21083.09, 21084.2, and 21084.3. AB 52 established that TCRs must be considered under CEQA and also provided for additional Native American consultation requirements for the lead agency. Section 21074 describes a TCR as a site, feature, place, cultural landscape, sacred place, or object that is considered of cultural value to a California Native American Tribe and that is either of the following:
▪ On or determined to be eligible for the California Register of Historical Resources or a local historic register; or
▪ A resource determined by the lead agency, in its discretion and supported by substantial evidence, to be significant pursuant to criteria set forth in subdivision (c) of Section 5024.1.

AB 52 formalizes the lead agency–tribal consultation process, requiring the lead agency to initiate consultation with California Native American groups that are traditionally and culturally affiliated with the Project Site, including tribes that may not be federally recognized. Lead agencies are required to begin consultation prior to the release of a negative declaration, mitigated negative declaration, or environmental impact report.

Section 1 (a)(9) of AB 52 establishes that “a substantial adverse change to a tribal cultural resource has a significant effect on the environment.” Effects on TCRs should be considered under CEQA. Section 6 of AB 52 adds Section 21080.3.2 to the PRC, which states that parties may propose mitigation measures “capable of avoiding or substantially lessening potential significant impacts to a tribal cultural resource or alternatives that would avoid

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significant impacts to a tribal cultural resource.” Further, if a California Native American tribe requests consultation regarding Project alternatives, mitigation measures, or significant effects to TCRs, the consultation shall include those topics (PRC Section 21080.3.2[a]). The environmental document and the mitigation monitoring and reporting program (where applicable) shall include any mitigation measures that are adopted (PRC Section 21082.3[a]).

Local
City of Santee General Plan Conservation Element
The City of Santee does not maintain a local register of historic resources. As a result, the Property was not evaluated under local significance criteria. Nevertheless, the City of Santee General Plan serves to guide the City’s future development. This is accomplished through objectives and policies that serve as a long-term guide for physical, economic, and environmental growth. The Conservation Element of the Santee General Plan addresses water resources, land resources, archaeological and cultural sources, biological resources, and open space.

Section 4.3 of the Conservation Element discusses archaeological, cultural, and historic resources known to be within the City. The goal of the Conservation Element is to conserve open space, natural, and cultural resources.

According to Conservation Element Objective 8.0 (Preserve significant cultural resources), Policy 8.1, the City shall require either the preservation of significant historic or prehistoric sites, or the professional retrieval of artifacts prior to the development of a site, consistent with the provisions of CEQA. Preservation may include various measures including avoidance, preservation in place, incorporation into open space, or covering or capping. The type of preservation would depend upon the nature and significance of the archaeological resource and the practical requirements of the proposed land use. Policy 8.2 states that the City should require curation of any recovered artifacts as a condition of any cultural resources mitigation program.

4.2.3 Thresholds of Significance
The significance criteria used to evaluate the Project impacts to cultural, tribal cultural, and paleontological resources are based on CEQA Guidelines Appendix G. According to CEQA Guidelines Appendix G, a significant impact related to cultural, tribal cultural, and paleontological resources would occur if the Project would incur the following:

Cause a substantial adverse change in the significance of a historical resource pursuant to Section 15064.5.

Cause a substantial adverse change in the significance of an archaeological resource pursuant to Section 15064.5.

Disturb any human remains, including those interred outside of dedicated cemeteries.

Cause a substantial adverse change in the significance of a tribal cultural resource, defined in Public Resources Code section 21074 as either a site, feature, place, cultural landscape that is geographically defined in terms of the size and scope of the landscape, sacred place, or object with cultural value to a California Native American tribe, and that is (i) listed or eligible for listing in the California Register of Historical Resources, or in a local register of historical resources as defined in Public Resources Code section 5020.1(k).

Cause a substantial adverse change in the significance of a tribal cultural resource, defined in Public Resources Code section 21074 as either a site, feature, place, cultural landscape that is geographically defined in terms of the size and scope of the landscape, sacred place, or object with cultural value to a California Native American tribe, and that is (ii) a resource determined by the lead agency, in its discretion

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and supported by substantial evidence, to be significant pursuant to criteria set forth in subdivision (c) of Public Resources Code Section 5024.1. In applying the criteria set forth in subdivision (c) of Public Resource Code Section 5024.1, the lead agency shall consider the significance of the resource to a California Native American tribe.

Directly or indirectly destroy a unique paleontological resource or site or unique geologic feature.

4.2.4 Impact Analysis
A. Would the Project cause a substantial adverse change in the significance of a historical resource as defined in CEQA Guidelines Section 15064.5?
According to CEQA Guidelines Section 15064.5(a)(3), a historical resource includes any resource listed in or determined eligible for listing in the CRHR, or any resource the lead agency determines meets the CRHR criteria. The evaluation of resources within the Project Site did not identify any built‑environment resources or historic‑era structures that meet the criteria for listing in the CRHR.

Dudek prepared a Built Environment Area of Potential Effects (APE) memorandum for this Project and is included as Appendix C. The memorandum includes background research of historic aerials, the California Historical Resources Information System (CHRIS), the Built Environment Resource Directory, and the San Diego County Historic Property List. The findings determined that no known built environment resources are located within the Project Site, and none of the adjacent historic-age properties are listed in, or determined eligible for listing in the NRHP, CRHR, or included in a local register. Additionally, the Project would not include construction disturbance, demolition, non-compatible building or structural modifications, construction-related groundborne vibration, or property acquisitions. Project activities consist solely of vegetation management activities (hand labor, mechanical and chemical application) that would not physically alter any building, structure, or object and therefore the Project would not result in a substantial adverse change under CEQA Section 15064.5(b) and impacts would be less than significant.

B. Would the Project cause a substantial adverse change in the significance of an archaeological resource pursuant to CEQA Guidelines Section 15064.5?
The Project Site is located within the San Diego River corridor, a riparian and wetland landscape that retains areas of relatively low ground disturbance compared to the surrounding urban development and is considered to have elevated potential for prehistoric archaeological resources. The Records Search and the Cultural Resources Pedestrian Survey identified a total of nine cultural resources within the Project Site, including three six archaeological sites CA‑SDI‑005050 (bedrock milling; lithic and ceramic scatter), CA‑SDI‑010148 (lithic artifact scatter), CA-SDI-021860 (lithic scatter), SDRFM-DF-S-001 (historic period linear rock feature and refuse), SDRFM-DF-S-002 (historic period poured concrete pad and footing), and SDRFM‑DF‑S‑003 (prehistoric bedrock milling feature), and six three isolated finds (SDRFM-DF-I-001, SDRFM-DF-I-002, and SDRFM-DF-I-003) that do not meet the criteria for site designation.

Vegetation management and maintenance activities across three treatment zones would use a combination of hand labor (e.g., cutting, trimming) mechanical methods (e.g., mowing and mastication), and limited chemical treatment (e.g., EPA-approved herbicide). Ground disturbance could occur where crews access treatment areas via existing roads and trails, conduct overland travel by foot (including off‑trail travel in some locations), and where mechanical equipment operates in accessible areas to remove

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or rearrange vegetation and biomass. Due to this and the Project’s location within the San Diego River corridor, there is an increased potential that Project associated ground disturbance would have the potential to impact unanticipated archaeological resources. For this reason, the Project Site should be treated as potentially sensitive for archaeological resources. With Implementation of MM CUL-1: Resource Avoidance, and MM CUL-2: Cultural Resources Monitoring, the Project would avoid direct impacts to the three identified archaeological sites and would reduce potential impacts to unanticipated archaeological resources. Therefore, with incorporation of MM CUL-1 and MM CUL-2, impacts to archaeological resources would be less than significant.

C. Would the Project disturb any human remains, including those interred outside of formal cemeteries? No prehistoric or historic burials were identified within or immediately adjacent to the Project Site as a result of the CHRIS records search, NAHC SLF search, or pedestrian survey. Moreover, the Project Site is not part of a dedicated cemetery and as such, the likelihood of disturbing human remains is low. However, the possibility of encountering human remains within the Project Site exists. In the unexpected event that human remains are unearthed during construction activities, impacts would be potentially significant.

However, because inadvertent discovery of human remains cannot be ruled out, to reduce potential impacts, MM CUL-3 requires that if human remains are discovered, all work in the vicinity of the find shall stop and the County Coroner and the City shall be notified immediately. If the remains are determined to be Native American, the County Coroner would notify the NAHC, which would determine and notify an MLD.

With incorporation of MM CUL--3, impacts associated with human remains would be less than significant.

D. Would the Project cause a substantial adverse change in the significance of a tribal cultural resource, defined in Public Resources Code Section 21074 as either a site, feature, place, cultural landscape that is geographically defined in terms of the size and scope of the landscape, sacred place, or object with cultural value to a California Native American tribe, and that is listed or eligible for listing in the California Register of Historical Resources, or in a local register of historical resources as defined in Public Resources Code Section 5020.1(k)? As part of the Cultural Resources Assessment Report (Appendix D), records of the CHRIS and SLF were completed in October and December 2025. Based on the CHRIS records search, the anticipated site type within the Project Site consisted of prehistoric artifact scatters and features.

The NAHC was contacted through a formal SLF request, and the commission responded by email indicating that known Native American cultural resources are present in the vicinity of the Project Site. The City sent AB 52 letters on March 20, 2026, and no responses were received. Therefore, no TCRs have been identified by California Native American tribes as part of the City’s AB 52 notification and consultation process. One newly recorded resource, SDRFM-DF-S-003, contains a bedrock milling feature and may retain native American cultural value; however, it is recommended not eligible for listing in the NRHP or CRHR because it appears to have been relocated, lacks associated archaeological deposits, and does not meet the criteria for significance.

Although the resource is not eligible for listing in the CRHR, avoidance and monitoring is recommended for potential Tribal significance. With implementation of MM CUL-1 and MM CUL-2, the Project would avoid impacts to areas of potential Tribal cultural importance. Impacts are considered less than significant with mitigation incorporated.

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E. Would the Project cause a substantial adverse change in the significance of a tribal cultural resource, defined in Public Resources Code Section 21074 as either a site, feature, place, cultural landscape that is geographically defined in terms of the size and scope of the landscape, sacred place, or object with cultural value to a California Native American tribe, and that is a resource determined by the lead agency, in its discretion and supported by substantial evidence, to be significant pursuant to criteria set forth in subdivision (c) of Public Resources Code Section 5024.1? In applying the criteria set forth in subdivision (c) of Public Resource Code Section 5024.1, the lead agency shall consider the significance of the resource to a California Native American tribe.

One cultural resource identified (SDRFM-DF-S-003) contains a bedrock milling feature that may have cultural value. However, it is not considered a TCR because it is not eligible for the CRHR, does not meet CEQA’s TCR criteria, and lacks associated archaeological deposits. The Sacred Lands File returned a positive indication of cultural resources inventory in the vicinity of the Project Site; however, the City sent AB 52 letters on March 20, 2026, and no responses were received. Therefore, no TCRs have been identified within the Project Site to date through the consultation process.

The archaeological sensitivity of the Project Site is considered to be moderate. For this reason, the Project Site should be treated as potentially sensitive for archaeological resources; MM CUL-1 is required to reduce potential impacts to unanticipated discovery of cultural resources and TCRs, and MM CUL-2 would reduce the significance of impacts associated with any potential buried, currently unrecorded/unknown TCRs.

Impacts are considered less than significant with mitigation incorporated.

4.2.5 Mitigation Measures and Level of Significance
After Mitigation
A. Would the Project cause a substantial adverse change in the significance of a historical resource as defined in CEQA Guidelines Section 15064.5?
The Project would not result in potentially significant impacts with regard to a substantial adverse change in significance of a historical resource pursuant to CEQA Guidelines Section 15064.5. Impacts associated with historical resources would be less than significant.

B. Would the Project cause a substantial adverse change in the significance of an archaeological resource pursuant to CEQA Guidelines Section 15064.5?
The Project would result in potentially significant impacts with regard to a substantial adverse change in the significance of an archaeological resource pursuant to CEQA Guidelines Section 15064.5. With incorporation of MM CUL-1 and MM CUL-2, impacts associated with archaeological resources would be less than significant.

MM CUL-1 Resource Avoidance. Measures shall be taken to prevent inadvertent disturbance of archaeological resource sites CA-SDI-005050, CA-SDI-010148, SDRFM-DF-S- and002, and SDFRM-DF-S-003. Prior to the commencement of any ground-disturbing activities within 100 feet of the resource boundaries of CA-SDI-005050, CA-SDI-010148, SDRFM-DF-S002, and SDRFM-DF-S-003, temporary work buffers shall be placed to protect the sites from inadvertent disturbances associated with project implementation. Following Project implementation within the vicinity of CA-SDI-005050, CA-SDI-010148, SDRFM-DF-S-002,

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and SDRFM-DF-S-003, the temporary work buffers shall be removed. Temporary work buffers may include exclusionary fencing, flagging, and/or Environmentally Sensitive Area (ESA) signage. An archaeological monitor shall guide the placement and erection of the temporary work buffers to ensure archaeological sites CA-SDI-005050, CA-SDI-010148, SDRFM-DF-S-002, and SDRFM-DF-S-003 are properly protected.

MM CUL-2 Cultural Resources Monitoring. To mitigate for potential impacts to previously unknown, buried cultural resources within the Project APE and to prevent impacts to known archaeological resources, an archaeological monitoring program shall be implemented pursuant to the City of Santee (City) regulations, the California Environmental Quality Act (CEQA), and Section 106 of the National Historic Preservation Act and shall include the following requirements:
▪ Pre-Construction
- The applicant shall contract a Secretary of Interior qualified Lead Archaeologist to oversee the cultural monitoring program. The Lead Archaeologist shall contract with a Kumeyaay monitor to conduct Native American monitoring for the Project.

The Lead Archaeologist and Kumeyaay Native American monitor(s) shall attend the pre-construction meeting to explain the monitoring requirements. ▪ Construction
- Monitoring. Both the archaeological and Kumeyaay Native American monitor(s) are to be on site during initial ground-disturbing activities. The frequency and location of monitoring of native soils will be determined by the Lead Archaeologist in consultation with the Kumeyaay Native American monitor(s). - If cultural resources are identified:
- Both the archaeological and Kumeyaay Native American monitor(s) have the authority to divert or temporarily halt ground disturbance operations in the area of the discovery.
- The archaeological monitor shall contact the Lead Archaeologist. - The Lead Archaeologist shall contact the City.
- The Lead Archaeologist in consultation with the City and Kumeyaay Native American monitor(s) shall determine the significance of discovered resources.

Construction activities will be allowed to resume after the City has concurred with the significance evaluation.

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- Isolates and non-significant deposits shall be minimally documented in the field.

Should the isolates and non-significant deposits not be collected by the archaeological monitor, the Kumeyaay Native American monitor(s) may collect the cultural material for transfer to a Tribal curation facility or repatriation program. - If cultural resources are determined to be potentially significant, avoidance measures will be developed by the Lead Archaeologist in consultation with the Kumeyaay Native American monitor(s) and approved by the City. If avoidance is not feasible, a research design and data recovery plan shall be prepared by the Lead Archaeologist in consultation with the Kumeyaay Native American monitor(s) and approved by the City. The preferred option is avoidance. - If human remains are identified
- Upon the identification of possible human remains, no further disturbance shall occur in the area of the find until procedures stipulated in Public Resources Code Section 5097.98, CEQA Section 15064.5 and Health and Safety Code Section 7050.5 are completed.
▪ Upon completion of project ground disturbance, a final report shall be prepared substantiating that earth-disturbing activities are completed and whether cultural resources were encountered. A copy of the final report shall be submitted to the South Coastal Information Center and any culturally affiliated tribe who requests a copy.

C. Would the Project disturb any human remains, including those interred outside of formal cemeteries? The Project would result in potentially significant impacts associated with the disturbance of human remains, including those interred outside of formal cemeteries. With incorporation of MM CUL-3, impacts associated with human remains would be less than significant with mitigation incorporated.

MM CUL-3 Unanticipated Discovery of Human Remains. In order to mitigate impacts to human remains to a level that is less than significant, procedures for proper treatment of unanticipated discoveries must comply with the California Environmental Quality Act (CEQA) Guidelines. In the event of discovery of unanticipated human remains, personnel shall comply with Public Resources Code Section 5097.98, CEQA Section 15064.5, and Health and Safety Code Section 7050.5 during earth-disturbing activities:

If any human remains are discovered, the construction personnel or the appropriate representative shall contact the County Coroner and the City. Upon identification of human remains, no further disturbance shall occur in the area of the find until the County Coroner has made the necessary findings as to origin. If the remains are determined to be of Native American origin, the Most Likely Descendant, as identified by the Native American Heritage Commission, shall be contacted by the property owner or their representative in order to determine proper treatment and disposition of the remains. The immediate vicinity where the Native American human remains are located is not to be damaged or disturbed by further development activity until consultation with the Most Likely Descendant regarding their recommendations as required by California Public Resources Code Section 5097.98 has been conducted. California Public Resources Code Section 5097.98, CEQA Section 15064.5 and Health and Safety Code Section 7050.5 shall be followed.

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D. Would the Project cause a substantial adverse change in the significance of a tribal cultural resource, defined in Public Resources Code Section 21074 as either a site, feature, place, cultural landscape that is geographically defined in terms of the size and scope of the landscape, sacred place, or object with cultural value to a California Native American tribe, and that is listed or eligible for listing in the California Register of Historical Resources, or in a local register of historical resources as defined in Public Resources Code Section 5020.1(k)? The Project would result in potentially significant impacts if TCRs were found during project activities. With implementation of MM CUL-1 and MM CUL-2, the Project would avoid inadvertent disturbance to resources with potential tribal cultural significance and ensure that tribal monitors participate directly in ground-disturbing activities and in all vegetation management activities decisions for discoveries. Impacts to TCRs would be less than significant with mitigation incorporated.

E. Would the Project cause a substantial adverse change in the significance of a tribal cultural resource, defined in Public Resources Code Section 21074 as either a site, feature, place, cultural landscape that is geographically defined in terms of the size and scope of the landscape, sacred place, or object with cultural value to a California Native American tribe, and that is a resource determined by the lead agency, in its discretion and supported by substantial evidence, to be significant pursuant to criteria set forth in subdivision (c) of Public Resources Code Section 5024.1? In applying the criteria set forth in subdivision (c) of Public Resource Code Section 5024.1, the lead agency shall consider the significance of the resource to a California Native American tribe.

The Project would result in potentially significant impacts associated with the disturbance of TCRs because one resource (SDRFM-DF-S003) contains- a bedrock milling feature that may have Native American cultural value and the Project Site is considered moderately sensitive for cultural resources. With implementation of MM CUL-1 and MM CUL-2, the potential for inadvertent disturbance to TCRs would be minimized, and any discovery of Native American human remains would be treated in compliance with state law. Therefore, impacts associated with TCRs would be less than significant with mitigation incorporated.

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4.3 Hazards and Hazardous Materials
This section evaluates the effects of proposed San Diego River Fire Hazard Mitigation Program: Fuels Management Plan (Project) implementation on hazards and hazardous materials conditions. The following analysis identifies associated regulatory requirements, evaluates potential impacts, and identifies mitigation measures, if necessary to reduce or avoid significant impacts, related to the implementation of the Project.

4.3.1 Existing Conditions
Project Site Conditions
The Project Site is situated within a wildland–urban interface setting and is characterized by a river corridor containing riparian habitats, wetlands, open space, and restored areas, with adjacent residential and commercial development on both sides of the corridor. Existing land uses within the Project Site are primarily open space and recreation-oriented, including multi-use public access trails, parkland, and natural areas.

The Project Site does not contain industrial operations, permanent structures associated with hazardous materials handling, or land uses involving the routine storage, use, or disposal of hazardous or acutely hazardous materials.

Existing hazards within the corridor are instead primarily related to wildfire risk, including dense vegetation, invasive species, accumulated biomass, and ignition potential associated with human access and adjacent development.

These existing conditions form the baseline context for the proposed fuels reduction and hazard mitigation activities evaluated in this Environmental Impact Report.

Contaminated Sites
A search of the Regulated Site Portal identified several listings of contaminated sites around the Project Site. These listings are for a variety of sites that handle hazardous materials and/or wastes, have environmental permits for operations, or have had release of hazardous materials. Government Code Section 65962.5 requires the California Environmental Protection Agency (CalEPA) to compile a list of hazardous waste and substances sites (Cortese List).

While the Cortese List is no longer maintained as a single list, the following databases provide information that meet the Cortese List requirements:

1. List of Hazardous Waste and Substances sites from Department of Toxic Substances Control EnviroStor database (HSC 25220, 25242, 25356, and 116395)

2. List of LUST Sites by County and Fiscal Year from the State Water Resources Control Board GeoTracker database (HSC 25295)

3. List of solid waste disposal sites identified by the State Water Resources Control Board with waste constituents above hazardous waste levels outside the waste management unit (Water Code Section 13273[e] and 14 CCR Section 18051)

4. List of “active” Cease and Desist Orders and Cleanup and Abatement Orders from the State Water Resources Control Board (Water Code Sections 13301 and 13304)

5. List of hazardous waste facilities subject to corrective action pursuant to Section 25187.5 of the Health and Safety Code, identified by the Department of Toxic Substances Control

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In addition to Cortese List sites and the CalEPA Regulated Site Portal (discussed in Current Hazardous Material Uses and Hazardous Waste Generation), the following databases provide additional information regarding potential environmental contamination within the State of California. Table 4.3-1 provides a summary of these databases.

Table 4.3-1. Online Database Listings
Database Details
Department of Toxic Substance Control
(DTSC) EnviroStor
https://www.envirostor.dtsc.ca.gov/
The DTSC’s data management system for tracking cleanup, permitting, enforcement, and investigation efforts at hazardous waste facilities and sites with known contamination or sites where there may be reasons for further investigation.

Regional Water Quality Control Board
(RWQCB) GeoTracker
http://geotracker.waterboards.ca.gov/
The California RWQCB’s data management system for sites that impact, or have the potential to impact, water quality in California, with emphasis on groundwater. GeoTracker contains records for sites that require cleanup, various unregulated projects, and permitted facilities. Sites include Leaking Underground Storage Tanks, Department of Defense, Cleanup Program, Irrigated Lands, Oil and Gas Production, Permitted Underground Storage Tanks, and Land Disposal Sites.

National Pipeline Mapping System
https://www.npms.phmsa.dot.gov/
The National Pipeline Mapping System Public Map Viewer is a web-based application designed to assist the general public with displaying and querying data related to gas transmission and hazardous liquid pipelines, liquefied natural gas plants, and breakout tanks under Department of Transportation Pipeline and Hazardous Material Safety Administration jurisdiction.

CalRecycle Solid Waste Information
System (SWIS)
https://www2.calrecycle.ca.gov/
SolidWaste/Site/Search
The SWIS database contains information on solid waste facilities, operations, and disposal sites throughout the state. These include landfills, transfer stations, compositing sites, engineered conversion facilities, and closed disposal facilities.

California Geologic Energy Management
Division (CalGEM) Well Finder
https://www.conservation.ca.gov/calgem/
Pages/Wellfinder.aspx
The CalGEM Well Finder database identifies oil and gas wells and related facilities throughout the state.

Source: DTSC 2026; CalGEM 2026.

A regulatory database search of existing sites was completed within the Project Site. The database search specifically identified sites that have had reported releases of hazardous materials or waste, including active contaminated sites that are currently under assessment and/or remediation. Some of the sites identified on these databases include closed cases, which received regulatory closure because the contamination levels at those facilities or sites were found to be below regulatory thresholds, contamination levels were determined to not be a threat to human health or the environment, or remediation was completed to the satisfaction of the regulatory agency overseeing the effort.

EnviroStor Database Sites
The EnviroStor database includes both state cleanup and Federal Superfund sites. No EnviroStor-listed sites are located on or directly adjacent to the Project Site. The closest EnviroStor-listed site is the Coneen Property, located at 8656 Cuyamaca Street, which is designated by the Department of Toxic Substance Control (DTSC) as a Site Evaluation and is located approximately 5,100 feet south of the Project Site, on the opposite side of State Route 52.

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Given the distance, intervening roadway infrastructure, and site status, this site would not affect the Project Site or contribute to existing hazardous materials conditions within the Project area (DTSC 2026).

GeoTracker Database Sites
The GeoTracker database includes hazardous material release sites found in the Spills, Leaks, Investigations, and Cleanups program; the Leaking Underground Storage Tank program; military cleanup sites; and permitted land disposal sites (such as landfills). One GeoTracker-listed site is located within the Project Site, and 11 sites are located directly adjacent to the Project Site; all of these sites have received regulatory closure. No open GeoTracker sites are located within or directly adjacent to the Project Site (SWRCB 2026).

National Pipeline Mapping System
A review of the National Pipeline Mapping System identified a gas transmission pipeline located approximately 0.18 miles northwest of the Project Site (NPMS 2026). The National Pipeline Mapping System includes generalized locations of gas transmission pipelines regulated by the U.S. Department of Transportation (USDOT).

California Department of Resources Recycling and Recovery Solid Waste Information System Database Sites
A review of the CalRecycle Solid Waste Information System database identified two solid waste facilities within the City of Santee. The Santee Limited Volume Transfer Operation is an active solid waste operation located at 8502 Railroad Avenue, approximately 1.05 miles south of the Project Site. A second facility, also identified as Santee Limited Volume Transfer Operation, is listed as closed and is located near Mission Road at State Route 52/125, approximately 0.5 miles west of the Project Site (CalRecycle 2026). Neither facility is located on or directly adjacent to the Project Site.

California Geologic Energy Management Oil and Gas Wells No oil and gas wells, nor well fields, were identified on or overlapping the Project Site (CalGEM 2026).

Hazardous Materials
Definitions
California Health and Safety Code (HSC) Section 25260(d) defines hazardous material as a substance or waste that, because of its physical, chemical, or other characteristics, may pose a risk endangering human health or safety or of degrading the environment. Hazardous material includes, but is not limited to:

1. A hazardous substance, as defined in Section 25281 or subdivision (a) or Section 78075.

2. A hazardous waste, as defined in Section 25117.

3. A waste, as defined in Section 470 or as defined in Section 13050 of the Water Code.

Under 29 CFR 1910.1200, the Occupational Safety and Health Administration (OSHA) defines a hazardous chemical as any chemical that is a physical hazard or health hazard.

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Potential Existing Hazards and Contamination
Hazardous materials, if present in soils, can be distributed and dispersed by vegetation treatment activities, particularly those using heavy equipment. Soil contamination generally occurs in areas that are or have been previously developed, especially with industrial-type uses. Soil contamination can also occur in areas where pesticides have been historically applied, as well as in areas that have historically been mined or used for defense activities (e.g., an air force base). Contamination can also be associated with leaking utilities (e.g., leaking petroleum or gas pipelines, or leaking transformers on utility poles), or accidental spills. The proposed treatment landscape includes tree, shrub, and grass fuel types, sometimes near developed areas. Some of the treatable landscape may contain limited remnant contamination from previous defense, agricultural, or pesticide use; contamination from nearby urban areas; or may have been exposed to leaks from pipelines, transformers, or utility poles.

Schools
The closest schools to the Project Site include Carlton Oaks School, located approximately 0.52 miles northwest of the Project Site; Carlton Hills School, located approximately 0.25 miles north of the Project Site; Hill Creek School, located approximately 0.10 miles north of the Project Site; Santana High School, located approximately 0.55 miles north of the Project Site; Cajon Park School, located approximately 1.07 miles north of the Project Site; Sycamore Canyon School, located approximately 1.27 miles north of the Project Site; and Chet F. Harritt School, located approximately 0.90 miles southwest of the Project Site.

Airports
The closest airport to the Project Site is Gillespie Field Airport, located approximately 1.1 miles southwest of the Project Site. The Project Site is located within the Gillespie Field Airport Influence Area (AIA), Review Area 2, and the Federal Aviation Administration height notification boundary. Portions of the Project Site are also located within the 60-to-65-decibel (dB) Community Noise Equivalent Level (CNEL) noise exposure contour. The Project Site is located outside of designated airport safety zones (SDCRAA 2010).

Wildfire Risk
Portions of the Project Site are in areas designated as Moderate and High FHSZs, and the Project Site is bordered by areas designated as Moderate, High, and Very High FHSZs to the north and south (see Figure 3-4 Fire Hazard Severity Zones) (CAL FIRE 2026). Wildfire risks associated with the Project are discussed in Section 4.6, Wildfire, of this Environmental Impact Report.

4.3.2 Relevant Plans, Policies, and Ordinances
Federal
Code of Federal Regulations
The U.S. Environmental Protection Agency (EPA) is the primary federal agency responsible for enforcement and implementation of federal laws and regulations pertaining to hazardous materials. Applicable federal regulations pertaining to hazardous materials are contained mainly in the Code of Federal Regulations (CFR) Titles 29, 40, 42, and 49. Title 40 CFR Part 273 governs the collection and management of widely generated waste, including batteries, pesticides, mercury-containing equipment, and light bulbs. This regulation

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streamlines the hazardous waste management standards and ensures that such waste is diverted to the appropriate treatment or recycling facility.

Title 40 CFR Part 112 requires the preparation of a Spill Prevention, Control, and Countermeasure Plan if oil is stored in excess of 1,320 gallons in aboveground storage (or have a buried capacity of 42,000 gallons). Spill Prevention, Control, and Countermeasure regulations place restrictions on the management of petroleum materials and, therefore, have some bearing on hazardous materials management.

Title 40 CFR Part 61 established National Emission Standards for Hazardous Air Pollutants (NESHAP) and names asbestos-containing material as one of these materials. Asbestos-containing material use, removal, and disposal are regulated by EPA under this law. In addition, notification of friable asbestos-containing material removal prior to a proposed demolition project is required by this law.

Hazardous materials, as defined in the CFR, are listed in 49 CFR 172.101. These laws and associated regulations include specific requirements for facilities that generate, use, store, treat, and/or dispose of hazardous materials.

EPA also provides oversight and supervision of Federal Superfund investigation/remediation projects, evaluates remediation technologies, and develops hazardous materials disposal restrictions and treatment standards.

Comprehensive Environmental Response, Compensation, and Liability Act and the Superfund Amendments and Reauthorization Act of 1986
Congress enacted the Comprehensive Environmental Response, Compensation, and Liability Act, commonly known as Superfund, on December 11, 1980. The Comprehensive Environmental Response, Compensation, and Liability Act established prohibitions and requirements concerning closed and abandoned hazardous waste sites, provided for liability of persons responsible for releases of hazardous waste at these sites, and established a trust fund to provide for cleanup when no responsible party could be identified. The Superfund Amendments and Reauthorization Act amended the Comprehensive Environmental Response, Compensation, and Liability Act on October 17, 1986. The Superfund Amendments and Reauthorization Act stressed the importance of permanent remedies and innovative treatment technologies in cleaning up hazardous waste sites, required Superfund actions to consider the standards and requirements found in other state and federal environmental laws and regulations, provided new enforcement authorities and settlement tools, increased state involvement in every phase of the Superfund program, increased the focus on human health problems posed by hazardous waste sites, encouraged greater citizen participation in making decisions on how sites should be cleaned up, and increased the size of the trust fund to $8.5 billion.

Resource Conservation and Recovery Act of 1976, with Hazardous and Solid Waste Amendments of 1984
Federal hazardous waste laws are generally promulgated under the Resource Conservation and Recovery Act (RCRA). These laws provide for the “cradle to grave” regulation of hazardous wastes. Any business, institution, or other entity that generates hazardous waste is required to identify and track its hazardous waste from the point of generation until it is recycled, reused, or disposed. The DTSC is responsible for implementing the RCRA program and California’s own hazardous waste laws, which are collectively known as the Hazardous Waste Control Law. Under the Certified Unified Program Agency program, CalEPA has in turn delegated enforcement authority to counties for state law regulating hazardous waste producers or generators. The 1986 amendments to RCRA enabled the EPA to address environmental problems that could result from underground tanks storing petroleum and other hazardous substances. Some of the other mandates of this law include increased

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enforcement authority for EPA, more stringent hazardous waste management standards, and a comprehensive underground storage tank program.

Federal Insecticide, Fungicide, and Rodenticide Act
The Federal Insecticide, Fungicide, and Rodenticide Act (7 USC 136 et seq.) provides federal control of pesticide distribution, sale, and use. EPA was given authority under the Federal Insecticide, Fungicide, and Rodenticide Act to study the consequences of pesticide usage and require users (e.g., farmers, utility companies) to register when purchasing pesticides. Later amendments to the law required users to take exams for certification as applicators of pesticides. All pesticides used in the United States must be registered (licensed) by EPA. Registration assures that pesticides would be properly labeled and that if used in accordance with specifications, would not cause unreasonable harm to the environment.

Toxic Substances Control Act of 1976
The Toxic Substances Control Act of 1976 (15 USC 2605) banned the manufacturing, processing, distribution, and use of polychlorinated biphenyls (PCBs) in totally enclosed systems. PCBs are considered hazardous materials because of their toxicity; and they have been shown to cause cancer in animals, along with effects on the immune, reproductive, nervous, and endocrine systems, and studies have shown evidence of similar effects in humans (Appendix B, Section 6.4 of the Toxic Substances Control Act). The EPA Region 9 PCB Program regulates remediation of PCBs in several states, including California. 40 CFR Section 761.30(a)(1)(vi)(A) states that all owners of electrical transformers containing PCBs must register their transformers with EPA. Specified electrical equipment manufactured between July 1, 1978, and July 1, 1998, that does not contain PCBs, must be marked by the manufacturer with the statement “No PCBs” (Section 761.40[g]). Transformers and other items manufactured before July 1, 1978, containing PCBs must be marked as such.

Occupational Health and Safety Administration
OSHA is responsible for enforcement and implementation of federal laws and regulations pertaining to worker health and safety. Workers at hazardous waste sites must receive specialized training and medical supervision according to the Hazardous Waste Operations and Emergency Response regulations (29 CFR 1910.120).

Hazardous Materials Transportation Act
The transportation of hazardous materials is regulated by the Hazardous Materials Transportation Act (HMTA), which is administered by the Research and Special Programs Administration of the USDOT. HMTA provides USDOT with a broad mandate to regulate the transport of hazardous materials, with the purpose of adequately protecting the nation against risk to life and property, which is inherent in the commercial transportation of hazardous materials. The HMTA governs the safe transportation of hazardous materials by all modes, excluding bulk transportation by water. The Research and Special Programs Administration carries out these responsibilities by prescribing regulations and managing a user-funded grant program for planning and training grants for states and Indian tribes. USDOT regulations that govern the transportation of hazardous materials are applicable to any person who transports, ships, causes to be transported or shipped, or who is involved in any way with the manufacture or testing of hazardous materials packaging or containers. USDOT regulations pertaining to the actual movement govern every aspect of the movement, including packaging, handling, labeling, marking, placarding, operational standards, and highway routing. Additionally, the USDOT is responsible for developing curriculum to train for

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emergency response and administers grants to states and Indian tribes for ensuring the proper training of emergency responders. HMTA was enacted in 1975 and was amended and reauthorized in 1990, 1994, and 2005.

Emergency Planning Community Right-to-Know Act
The Emergency Planning Community Right-to-Know Act, also known as Superfund Amendments and Reauthorization Act Title III, was enacted in October 1986. This law requires any infrastructure at the state and local levels to plan for chemical emergencies. Reported information is then made publicly available so that interested parties may become informed about potentially dangerous chemicals in their community. Sections 301 through 312 of the Act are administered by EPA’s Office of Emergency Management. EPA’s Office of Information Analysis and Access implements the Emergency Planning Community Right-to-Know Act Section 313 program. In California, Superfund Amendments and Reauthorization Act Title III is implemented through the California Accidental Release Prevention Program (CalARP).

Federal Response Plan
The Federal Response Plan of 1999, as amended in 2003 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 operations 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 presidential declaration of a major disaster or emergency.

International Fire Code
The International Fire Code (IFC), created by the International Code Council, is the primary means for authorizing and enforcing procedures and mechanisms to ensure the safe handling and storage of any substance that may pose a threat to public health and safety. The IFC regulates the use, handling, and storage requirements for hazardous materials at fixed facilities. The IFC and the International Building Code use a hazard classification system to determine what measures are required to protect against structural fires. These measures may include construction standards, separations from property lines, and specialized equipment. To ensure that these safety measures are met, IFC employs a permit system based on hazard classification. The IFC is updated every three years.

Regional Screening Levels
The federal EPA provides regional screening levels (RSLs) for chemical contaminants to provide comparison values for residential and commercial/industrial exposures to soil, air, and tap water (drinking water). RSLs are available on the EPA’s website and provide a screening level calculation tool to assist risk assessors, remediation project managers, and others involved with risk assessment and decision-making. RSLs are also used when a site is initially investigated to determine if potentially significant levels of contamination are present to warrant further investigation. In California, the DTSC Human and Ecological Risk Office (HERO) incorporated the EPA RSLs into the HERO human health risk assessment. HERO created Human Health Risk Assessment Note 3, which incorporates HERO recommendations and DTSC-modified screening levels (DTSC-SLs) based on review of the EPA RSLs. The DTSC-SL should be used in conjunction with the EPA RSLs to evaluate chemical concentrations in environmental media at California sites and facilities.

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Federal Aviation Administration
Title 14 Code of Federal Regulations, Chapter 1, Subchapter E, Part 77 – Aeronautics and Space – Safe, Efficient Use, and Preservation of the Navigable Airspace This regulation establishes requirements for notifying the Federal Aviation Administration of certain construction activities and alterations to existing structures, in order to ensure there are no obstructions to navigable airspace.

For example, projects that include construction or alteration exceeding 200 feet in height above ground level are required to notify the Federal Aviation Administration.

State
California Environmental Protection Agency
CalEPA was created in 1991 by the Governor’s Executive Order W-5-91. Several state regulatory boards, departments, and offices were placed under the CalEPA umbrella to create a cabinet-level voice for the protection of human health and the environment and to assure the coordinated deployment of state resources. Among those responsible for hazardous materials and waste management are DTSC, Department of Pesticide Regulation, and Office of Environmental Health Hazard Assessment. CalEPA also oversees the unified hazardous waste and hazardous materials management regulatory program (Unified Program).

California Health and Safety Code and Code of Regulations HSC Chapter 6.95 and 19 California Code of Regulations (CCR) 2729 set out the minimum requirements for business emergency plans and chemical inventory reporting. These regulations require businesses to provide emergency response plans and procedures, training program information, and a hazardous materials chemical inventory disclosing hazardous materials stored, used, or handled on site. A business that uses hazardous materials or a mixture containing hazardous materials must establish and implement a business plan if the hazardous material is handled in certain quantities.

HSC Section 25501 states that “hazardous materials” include, but are not limited to, hazardous substances, hazardous waste, and any material that a handler or the administering agency has a reasonable basis for believing that it would be injurious to the health and safety of persons or harmful to the environment if released into the workplace or the environment. Hazardous materials refer generally to hazardous substances that exhibit corrosive, poisonous, flammable, and/or reactive properties and have the potential to harm human health and/or the environment.

The transport of hazardous waste materials is further governed by California HSC Section 25163 and CCR Title 22, Chapter 13. Specifically, HSC Section 25163 requires transporters of hazardous waste to hold a valid registration issued by the DTSC in his/her possession while transporting hazardous waste. Additionally, CCR Title 22, Chapter 13 includes a number of requirements, which include, but are not limited to, the requirement to receive an identification number and a registration certificate from DTSC; requirement to obtain a Uniform Hazardous Waste Manifest that has been properly completed and signed by generator and transporter prior to accepting hazardous wastes; and delivery of hazardous waste to authorized facilities only.

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California Department of Toxic Substances Control
The California DTSC, which is a department of CalEPA, is authorized to carry out the federal RCRA hazardous waste program in California to protect people from exposure to hazardous wastes. The department regulates hazardous waste, cleans up existing contamination, and looks for ways to control and reduce the hazardous waste produced in California, primarily under the authority of RCRA and in accordance with the California Hazardous Waste Control Law (California HSC Division 20, Chapter 6.5) and the Hazardous Waste Control Regulations (22 CCR Divisions 4 and 4.5). Permitting, inspection, compliance, and corrective action programs ensure that people who manage hazardous waste follow state and federal requirements and other laws that affect hazardous waste specific to handling, storage, transportation, disposal, treatment, reduction, cleanup, and emergency planning.

California Building Code
The State of California provides a minimum standard for building design through the California Building Code, which is located in Part 2 of CCR Title 24. Part 2 of the California Building Code is a fully integrated code based on the International Building Code. It is generally adopted on a jurisdiction-by-jurisdiction basis, subject to further modification based on local conditions. Commercial and residential buildings are plan-checked by local city and county building officials for compliance with the California Building Code. Typical fire safety requirements of the California Building Code include the installation of sprinklers in all high-rise buildings; the establishment of fire resistance standards for fire doors, building materials, and particular types of construction; and the clearance of debris and vegetation within a prescribed distance from occupied structures in wildlife hazard areas.

California Accidental Release Prevention Program
CalARP (19 CCR 2735.1 et seq.) regulates facilities that use or store regulated substances, such as toxic or flammable chemicals, in quantities that exceed established thresholds. Under the regulations, industrial facilities that handle hazardous materials above threshold quantities are required to prepare and submit a Risk Management Plan to the local Certified Unified Program Agency. The overall purpose of CalARP is to prevent accidental releases of regulated substances and reduce the severity of releases that may occur. CalARP requires businesses to have planning activities that are intended to minimize the possibility of an accidental release by encouraging engineering and administrative controls. It is further intended to mitigate the consequences of an accidental release, by requiring owners or operators of facilities to develop and implement an accident prevention program. CalARP meets the requirements of the EPA Risk Management Program, which was established pursuant to the Clean Air Act amendments.

California Division of Occupational Safety and Health
The California Division of Occupational Safety and Health is responsible for developing and enforcing workplace safety standards and ensuring worker safety in the handling and use of hazardous materials (8 CCR 1529). Among other requirements, the California Division of Occupational Safety and Health requires entities handling specified amounts of certain hazardous chemicals to prepare injury and illness prevention plans and chemical hygiene plans and provides specific regulations to limit exposure of construction workers to lead.

California Fire Code
CCR Part 9 of Title 24 refers to the California Fire Code, which contains regulations consistent with nationally recognized and accepted practices for safeguarding life and property from the hazards of the following: fire and

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explosion; dangerous conditions arising from the storage, handling, and use of hazardous materials and devices; and hazardous conditions in the use or occupancy of buildings or premises. The California Fire Code also contains provisions to assist emergency response personnel. The California Fire Code also establishes requirements intended to provide safety and assistance to firefighters and emergency responders during emergency operations.

The provisions of the California Fire Code apply to the construction, alteration, movement, enlargement, replacement, repair, equipment, use and occupancy, location, maintenance, removal, and demolition of every building or structure throughout California. The California Fire Code includes regulations regarding fire-resistancerate construction, fire protection systems such as alarm and sprinkler systems, fire service features such as fire apparatus access roads, means of egress fire safety during construction and demolition. There are fire-safetyrelated building standards referenced in other parts of Title 24. The California Fire Code is a fully integrated code based on the IFC.

California Wildland–Urban Interface Code
CCR Part 7 of Title 24 refers to the California Wildland–Urban Interface (WUI) Code. It establishes construction and site-development requirements for buildings located in fire-prone WUI areas, focusing on reducing structure ignitions during wildfires. It covers ignition-resistant building materials, exterior fire-resistant features such as roofing, siding, and glazing, vegetation management and defensible-space requirements, and standards for decks, vents, and accessory structures. The code also addresses fire-hazard severity classifications, access and water-supply criteria for firefighting, and design measures intended to limit ember intrusion, radiant-heat exposure, and direct flame contact. Together, these provisions support resilient development in communities facing increasing wildfire risk. The 2025 California WUI Code is a fully integrated code based on the 2024 International WUI Code.

California Emergency Services Act
Under the Emergency Services Act (California Government Code Section 8550 et seq.), the State of California developed an emergency response plan to coordinate emergency services provided by federal, state, and local agencies. Rapid response to incidents involving hazardous materials or hazardous waste is an integral part of the plan, which is administered by the Governor’s Office of Emergency Services. The Office of Emergency Services coordinates the responses of other agencies, including the EPA, California Highway Patrol, Regional Water Quality Control Boards (RWQCBs), air quality management districts, and county disaster response offices.

Toxic Substances Control Act
The EPA prohibited the use of PCBs in the majority of new electrical equipment starting in 1979 and initiated a phaseout for much of the existing PCB-containing equipment. The inclusion of PCBs in electrical equipment and the handling of those PCBs are regulated by the provisions of the Toxic Substances Control Act (15 USC 2601 et seq.).

Relevant regulations include labeling and periodic inspection requirements for certain types of PCB-containing equipment and highly specific safety procedures for their disposal. The state likewise regulates PCB-laden electrical equipment and materials contaminated above a certain threshold as hazardous waste; these regulations require that such materials be treated, transported, and disposed accordingly. At lower concentrations for non-liquids, RWQCBs may exercise discretion over the classification of such wastes.

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Environmental Screening Levels
Environmental Screening Levels provide conservative screening levels for over 100 chemicals found at sites with contaminated soil and groundwater. They are intended to help expedite the identification and evaluation of potential environmental concerns at contaminated sites. The Environmental Screening Levels were developed by San Francisco Bay RWQCB; however, they are used throughout the state. Although Environmental Screening Levels are not intended to establish policy or regulation, they can be used as a conservative screening level for sites with contamination.

Department of Toxic Substance Control Human and Ecological Risk Office Screening Levels DTSC screening levels were derived from the EPA RSLs using DTSC-modified exposure and toxicity factors for constituents in soil, tap water, and ambient air. The DTSC screening levels should be used in conjunction with the EPA RSLs and RWQCB Environmental Screening Levels to evaluate chemical concentrations in environmental media at California sites and facilities.

Regional and Local
San Diego County Department of Environmental Health and Quality The San Diego County Department of Environmental Health and Quality regulates and enforces state underground storage tank and aboveground petroleum storage tank installation and monitoring requirements, including permitting and inspecting, for businesses within San Diego County, including those in Santee. The County of San Diego (County) operates a Site Assessment and Mitigation Program to mitigate the release of contaminant materials. The San Diego County Department of Environmental Health and Quality is also responsible for administering the state’s Leaking Underground Fuel Tank program. The purpose of the program is to oversee the proper assessment and remediation of contaminants released from underground storage tanks.

San Diego County Air Pollution Control District
Although the California Air Resources Board is responsible for the regulation of mobile emission sources within the state, local air quality management districts and air pollution control districts are responsible for the development and implementation of rules and regulations designed to attain the National Ambient Air Quality Standards and California Ambient Air Quality Standards, as well as the permitting of new or modified sources, development of air quality management plans, and adoption and enforcement of air pollution regulations. The San Diego County Air Pollution Control District is the local agency responsible for the administration and enforcement of air quality regulations in San Diego County, where the City is located. The San Diego County Air Pollution Control District is responsible for monitoring air quality, as well as planning, implementing, and enforcing programs designed to attain and maintain state and federal ambient air quality standards within the SDAB.

Regional Water Quality Control Board
RWQCB implements the California Water Code, which regulates waste discharges to land. If a discharge of waste threatens a water of the state, a report of waste discharge or an application for a waiver of a report of waste discharge must be filed with the RWQCB. The RWQCB accomplishes its permitting responsibility by issuing either a general or site-specific permit (Waste Discharge Permit) or a waiver of a permit.

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County of San Diego Emergency Operations Plan
The San Diego County Emergency Operations Plan, approved in 2022, is a comprehensive emergency management system that provides for a planned response to disaster situations associated with natural disasters, technological incidents, and nuclear defense operations. The Emergency Plan includes operational concepts relating to various emergency situations, identifies components of the Emergency Management Organization and describes the overall responsibilities for protecting life and property and assuring the overall well-being of the population. The plan also identifies the sources of outside support that might be provided (through mutual aid and specific statutory authorities) by other jurisdictions, state and federal agencies, and the private sector.

San Diego County Multi-Jurisdictional Hazard Mitigation Plan The San Diego County Multi-Jurisdiction Hazard Mitigation Plan was originally prepared in July 2010 and updated in October 2017 to meet federal and state requirements for disaster preparedness to make the County eligible for funding and technical assistance from state and federal hazard mitigation programs. The plan includes a risk assessment to enable local jurisdictions to identify and prioritize appropriate mitigation actions to reduce losses from potential hazards, including flooding, earthquakes, fires, and human-made hazards. To address potential hazards, the plan then incorporates mitigation goals and objectives, mitigation actions and priorities, an implementation plan, and documentation of the mitigation planning process for each of the 22 participating jurisdictions, including Santee.

California Disaster and Civil Defense Master Mutual Aid Agreement As provided for in the California Emergency Services Act, the California Disaster and Civil Defense Master Mutual Aid Agreement was developed in 1950 and adopted by all 58 California counties. This statewide mutual aid system is designed to ensure that adequate resources, facilities, and other support are provided to jurisdictions whenever their own resources prove to be inadequate to cope with a given situation. San Diego County is located in Mutual Aid Region 6 of the state system, which also includes Imperial, Riverside, San Bernardino, Inyo, and Mono Counties.

Airport Land Use Compatibility Plan – Gillespie Field
The San Diego County Regional Airport Authority, designated as the Airport Land Use Commission for all public airports in the County of San Diego, adopted the Gillespie Field Airport Land Use Compatibility Plan (ALUCP) January 25, 2010 (last amended December 20, 2010). The ALUCP assists in achieving compatible land use development in the area surrounding Gillespie Field Airport. The ALUCP designates the AIA and contains projected noise contours, flight activity zones, a land use compatibility matrix, and plan recommendations for areas surrounding Gillespie Field. The AIA is delineated by using the projected 60 dB CNEL contour and is generally the area in which current and future airport-related noise, overflight, safety, and/or airspace protection factors may affect land uses or necessitate restrictions on uses. For the purposes of this analysis, the AIA is divided into Review Area 1 and Review Area 2 for Gillespie Field.

Gillespie Field Airport Influence Area Review Area 1 and Review Area 2 (SDCRAA 2010) ▪ Review Area 1 consists of locations where noise or safety concerns may necessitate limitations on the types of land use actions. Specifically, Review Area 1 encompasses locations exposed to aircraft noise levels of 60 dB CNEL or greater together with all of the safety zones identified in the ALUCP.

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▪ Review Area 2 consists of locations beyond Review Area 1 but within the airspace and/or overflight notification areas. Limits on the heights of structures, particularly in areas of high terrain, are the only restrictions on land uses within Review Area 2.

City of Santee Hazard Mitigation Plan
The purpose of the Hazard Mitigation Plan is to identify risks and ways to mitigate damage from natural and humancaused disasters. Goal 7 of the Plan, Hazardous Materials Release, outlines objectives and actions to monitor and prevent the release of hazardous materials, along with educational awareness to the public about the dangers (City of Santee 2023).

Santee General Plan
The City’s General Plan contains objectives and policies aimed at minimizing potential risks associated with hazards and hazardous materials. The Safety and Environmental Justice Element of the General Plan aims to reduce loss of life, injuries, and damage to property resulting from natural and human-caused public safety hazards including hazardous materials application, release and exposure, flooding, geologic and seismic hazards, fire, traffic hazards, and crime. Related objectives and policies of the Safety and Environmental Justice Element are listed below (City of Santee 2025).

City of Santee General Plan Safety and Environmental Justice Element Goal 4: Improve the City of Santee’s capacity to prevent and respond to emergencies and hazardous materials incidents.

Objective 8.0 Ensure the efficient control of emergency operations during natural or human-caused disasters Policy 8.1 Continue to hold periodic disaster exercises in cooperation with the appropriate state and federal agencies.

Policy 8.2 Update the adopted Santee Emergency Operations Plan periodically to ensure the safety of residents, employees, and visitors in times of natural or human-caused disaster.

Policy 8.3 Maintain an Emergency Operations Center to coordinate resources, information, and communication, which would strengthen the City of Santee’s ability to detect and respond to threats.

Objective 9.0 Minimize the risk of damage to persons, property and the environment caused by hazardous materials.

Policy 9.1 Continue to implement the County’s Hazardous Waste Management Plan or develop and implement an equivalent plan.

Policy 9.2 Continue to participate in the San Diego County Joint Powers Authority Hazardous Materials Response Team in dealing with hazardous materials incidents.

Policy 9.3 Require that any potential hazardous materials issues be fully investigated at the environmental review stage prior to project approval.

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Policy 9.4 Review any proposed uses involving the use, transport, storage or handling of hazardous waste to ensure that such uses will not represent a significant risk to surrounding uses or the environment.

Policy 9.6 Control the location, manufacture, storage or use of hazardous materials in Santee through Zoning Ordinance implementation and the Development Review process.

Policy 9.7 Encourage safe and proper disposal of household hazardous waste.

Policy 9.8 Promote safe, environmentally sound means of solid waste disposal for the community.

Policy 9.10 Continue to implement the Construction and Demolition Diversion Ordinance as required by Cal Recycle.

Santee Municipal Code
The Santee Municipal Code is a compilation of the Santee City Charter and all regulatory and penal ordinances and certain administrative ordinances adopted by the City Council. The Santee Municipal Code includes Chapter 11.04, California Building Code; Chapter 11.17, California Wildland-Urban Interface Code; Chapter 11.18, California Fire Code; and Chapter 11.24, Construction and Improvement Standards.

4.3.3 Thresholds of Significance
The significance criteria used to evaluate the Project impacts to hazards, hazardous materials, and wildfire are based on California Environmental Quality Act Guidelines Appendix G. According to California Environmental Quality Act Guidelines Appendix G, a significant impact related to the Project would occur if the Project would incur the following:

Create a significant hazard to the public or the environment through the routine transport, use, or disposal of hazardous materials.

Create a significant hazard to the public or the environment through reasonably foreseeable upset and accident conditions involving the release of hazardous materials into the environment.

Emit hazardous emissions or handle hazardous or acutely hazardous materials, substances, or waste within one-quarter mile of an existing or proposed school.

Be located on a site which is included on a list of hazardous materials sites compiled pursuant to Government Code Section 65962.5 and, as a result, would create a significant hazard to the public or the environment.

For a project located within an airport land use plan, or, where such a plan has not been adopted, within two miles of a public airport or public use airport, would the project result in a safety hazard or excessive noise for people residing or working in the project area? Impair implementation of or physically interfere with an adopted emergency response plan or emergency evacuation plan.

Expose people or structures, either directly or indirectly, to a significant risk of loss, injury, or death involving wildland fires.

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4.3.4 Impact Analysis
A. Would the Project create a significant hazard to the public or the environment through the routine transport, use, or disposal of hazardous materials?
Implementation of the Project would involve temporary and intermittent transport and use of hazardous materials during active vegetation management activities. After initial treatment, maintenance intervals will vary depending on vegetation type, treatment zone, and treatment technique determined by a biannual inspection of the Project Site, Typical hazardous materials used for treatment and maintenance activities would include fuel and lubricants for hand labor and mechanical equipment, and potentially herbicides where needed based on site conditions. The quantities and types of materials would be consistent with standard vegetation treatment operations, and their use would be limited to the duration and locations of treatment activities.

The Project includes best management practices (BMPs) that are incorporated into the Project design to reduce the potential for hazardous materials to create hazards during routine handling during treatment and maintenance activities. The Fuels Treatment Plan (FTP) specifies BMPs requiring that tools/equipment be serviced and fueled only in locations that would not allow grease, oil, fuel, or other hazardous materials to pass into streams or retained vegetation (Hand Labor BMP-6 and Water Quality BMP-1); that spill kits be available (Mechanical BMP-16 and Water Quality BMP-3); fueling occur in identified refueling areas with secondary containment; and tools, lubricants, and fuels be stored away from watercourses with secondary containment and labeling (Water Quality BMP-1, 2, and 4). These measures would reduce the potential for accidental releases and limit exposure pathways to sensitive resources, including waterways.

If chemical (herbicidal) treatment is used, it would be a limited, secondary tool rather than a primary treatment method and would be restricted to the use of EPA-approved herbicides. The FTP specifies that herbicide use would be considered only when other treatment techniques are infeasible or ineffective for achieving vegetation management and maintenance standards (Chemical BMP-1). Herbicidal application would require appropriate training/licensing, and the FTP specifies that herbicide application would occur only under a prescription prepared by a state-licensed pest control adviser (Chemical BMP-2). In addition, the FTP includes runoff protective BMPs: herbicide use would be prioritized as localized/direct application rather than foliar spraying, would follow required transport/mixing/loading procedures, and would be timed to minimize impacts, specifically including avoidance of application when local rainfall greater than 0.5 inches is forecast within 24 hours of planned application (Chemical BMP-3, Chemical BMP 6-10). The FTP also specifies use of EPA-approved aquatic-use herbicides/surfactants registered for use by the California Department of Pesticide Regulation where aquatic vegetation control is needed, and compliance with applicable label instructions and regulatory requirements (Chemical BMP-4-5).

Biomass disposal would occur using the disposal methods identified in the FTP, which are designed to reduce hazards and avoid environmental impacts. The FTP identifies off-site transport to an approved green waste facility as the preferred disposal method because it provides the greatest long-term hazard reduction by preventing cut material from remaining on site and avoiding concentrated piles of drying fuels. Where off-site hauling is inefficient or unnecessary, the FTP allows on-site broadcast of chips (with limits to avoid deep accumulations and explicit avoidance of broadcasting within jurisdictional streambeds) and lop-andscatter only sparingly where other methods are not feasible and with controls to avoid creating slash concentrations. For areas requiring specialized handling, the FTP includes species-specific containment and disposal requirements, such as Arundo, which must be contained immediately by bundling or bagging

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and transported off site to prevent spread by fragments. The FTP further requires that disposal practices avoid unauthorized deposition of material in stream channels and comply with applicable permit conditions, including federal, state, and local permits from U.S. Army Corps of Engineers, the San Diego Regional Water Board, and California Department of Fish and Wildlife, thereby reducing the potential for environmental hazards during handling and disposal.

Because hazardous materials use would be temporary and because the Project incorporates the FTP’s BMPs that address equipment inspection, fueling/servicing controls, secondary containment, spill preparedness, herbicide licensing and minimized use, herbicide application timing restriction, and controlled biomass disposal/containment, the Project would not create a significant hazard to the public or the environment through the routine transport, use, or disposal of hazardous materials. Therefore, impacts would be less than significant.

B. Would the Project create a significant hazard to the public or the environment through reasonably foreseeable upset and accident conditions involving the release of hazardous materials into the environment? Reasonably foreseeable accidental releases could include small spills during fueling/servicing of equipment, leaks from equipment, or herbicide spills during transport or mixing/loading. Project BMPs included directly address scenarios that would involve spills through routine inspection to prevent leaking fluids; refueling in designated areas with secondary containment; spill kits at refueling areas; and requirement that “hazardous materials spill kits are available on all heavy equipment” (Hand Labor BMP6, Water Quality BMP-1-4, and Mechanical BMP-16).

In addition, vegetation treatment and maintenance activities, particularly those involving mechanical equipment, have the potential to disturb surface soils. In general, soil contamination, where present, is most commonly associated with previously developed or industrialized areas, historic agricultural uses involving pesticides, or accidental spills or leaking infrastructure. The Project Site consists primarily of tree, shrub, and grass fuel types within an open-space river corridor, with limited historic development, and no known hazardous materials cleanup sites are located on or directly adjacent to the Project Site.

The FTP further includes specific BMPs for chemical treatment that reduce both the likelihood and potential magnitude of accidental releases by limiting herbicide use to situations where other techniques are infeasible or ineffective, requiring consultation with a licensed pest control adviser and consistency with all label instructions, minimizing foliar spray applications in favor of localized/direct application methods, and implementing timing restrictions to reduce runoff potential (Chemical BMP-1-11).

In the event of an accidental release, the Project also includes BMPs for spill response and cleanup, including immediate containment of released materials using on-site spill kits, proper collection and disposal of contaminated materials at approved facilities, and removal of any contaminated soils, as necessary, in accordance with applicable regulations (Mechanical BMP-16 and Water Quality BMP-3).

These measures are intended to limit the extent and duration of exposure and prevent migration of hazardous materials to sensitive resources, including waterways.

Given the Project’s BMPs that are aimed toward preventing spills and are directly responsive to spill mechanisms, the potential for a significant accidental release affecting the public or environment would be low. The Project would not create a significant hazard under upset/accident conditions because accidental release pathways are addressed through BMPs requiring secondary containment, spill kits, equipment

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inspection, controlled fueling practices, and constrained herbicide application practices. Therefore, impacts would be less than significant.

C. Would the Project emit hazardous emissions or handle hazardous or acutely hazardous materials, substances, or waste within one-quarter mile of an existing or proposed school? As discussed under Section 4.3.1, Existing Conditions, above, the Project Site is located less than 0.25 miles from two existing schools, Carlton Hills School (0.25 miles south) and Hill Creek School (0.10 miles south), with six additional schools located within an approximately 2-mile radius of the Project Site. Project activities would be temporary and intermittent after initial treatment. Maintenance intervals will vary depending on vegetation type, treatment zone, and treatment technique determined by a biannual inspection of the Project Site. It is anticipated the maintenance activities will occur annually. Activity would occur only during active vegetation management implementation periods and would not involve ongoing industrial operations or long-term stationary emission sources. Activities would include short-term operation of hand and mechanical equipment and potentially limited, localized herbicide application conducted under the constraints described in the FTP (licensed personnel, pest control adviser prescription, label compliance, minimized foliar spraying, and timing constraints to reduce runoff risk).

As discussed above under Thresholds A and B, the Project’s transport, use and handling of hazardous materials would result in less-than-significant impacts related to both routine operations and reasonably foreseeable upset or accident conditions. In addition, the FTP includes BMPs specifically intended to prevent off-site movement of herbicides, including limiting herbicide use to situations where other methods are infeasible or ineffective; prioritizing localized or direct application methods over broadcast spraying; avoiding application during unsuitable weather conditions (such as high winds) that could increase drift potential; implementing timing restrictions; and complying with all applicable label requirements (Chemical BMP-1-11). These measures are designed to contain herbicides within the Project Site and prevent exposure to nearby sensitive receptors, including schools. While schools are present in the surrounding area, the Project’s handling of hazardous materials associated with the Project would be limited in scope, temporary in duration, and tightly controlled. Hazardous materials associated with the Project would be limited to common fuels for equipment and potentially herbicides, used only as needed and only during implementation activities.

Based on the temporary nature of Project activities, the limited and controlled use of hazardous materials, and the incorporation of BMPs that minimize drift, emissions, and off-site exposure, the Project would not emit hazardous emissions or handle hazardous materials in a manner that would pose a significant hazard to schools within 0.25 miles of the Project Site. Therefore, impacts to schools within 0.25 miles of the Project Site would be less than significant.

D. Would the Project be located on a site which is included on a list of hazardous materials sites compiled pursuant to Government Code Section 65962.5 and, as a result, would create a significant hazard to the public or the environment?
Government Code Section 65962.5 establishes the statutory basis for compiling information on hazardous materials sites, commonly referred to as the Cortese List. Although the Cortese List is no longer maintained as a single consolidated list, information that satisfies Section 65962.5 requirements is available through databases maintained by the DTSC, the State Water Resources Control Board, and other regulatory agencies. A regulatory database search was conducted to identify sites listed pursuant to Government Code

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Section 65962.5 that overlap the Project Site or are located within an appropriate buffer area. The search did not identify any listed hazardous materials sites within the Project Site. Therefore, implementation of the Project would not result in a significant hazard to the public or the environment under this threshold.

The proposed Project consists of vegetation management activities, including hand, mechanical, and limited chemical treatments. Project components do not include excavation, grading, trenching, or other subsurface disturbance. Accordingly, the Project would not involve activities that typically create pathways for encountering or mobilizing contaminated soil or groundwater.

Therefore, because the Project is not located on a site included on a list of hazardous materials sites compiled pursuant to Government Code Section 65962.5, impacts would be less than significant.

E. For a project located within an airport land use plan, or, where such a plan has not been adopted, within two miles of a public airport or public use airport, would the project result in a safety hazard or excessive noise for people residing or working in the project area?
City planning documents indicate that land use compatibility with the Gillespie Field Airport is governed by the applicable ALUCP. The ALUCP establishes safety zones, noise contours, and AIAs where certain development activities are subject to review. The proposed Project consists of vegetation management activities within an existing river corridor and does not include construction of occupied structures, new land uses, or land use intensification. The Project would not introduce residential uses, high-occupancy facilities, tall structures, or other features that could interfere with airport operations or airspace safety.

The Project Site is located approximately 1.1 miles southwest of Gillespie Field Airport and partially within the 60 to 65 dB CNEL noise exposure contour. The Project Site is located outside designated airport safety zones and does not include proposed uses that are sensitive to aircraft noise or overflight activity. The Project is located within Gillespie Field Review Area 2 and within the Federal Aviation Administration height notification boundary. Review Area 2 also includes requirements related to residential overflight notification; however, no residential or other noise-sensitive uses are proposed as part of the Project.

Therefore, no conflicts with ALUCP compatibility policies would occur. Because the Project does not propose new land uses, occupied structures, or development within AIAs, it would not result in an airport-related safety hazard or excessive noise exposure for people residing or working in the Project Site. Therefore, impact would be less than significant.

F. Would the Project impair implementation of or physically interfere with an adopted emergency response plan or emergency evacuation plan?
The Project would occur within a river corridor that includes public access trails and multiple access points.

Project access routes and staging areas would be coordinated by the contractor in coordination with the City and emergency service providers. To the extent feasible, staging areas would be located away from residential areas and key access points, and access planning would be designed to maintain emergency response capability during Project implementation.

The FTP anticipates that temporary closures or access restrictions may be necessary for recreational trails or localized work areas during active treatment for public safety. These temporary restrictions would apply to nonemergency recreational access and would not affect designated emergency evacuation routes or emergency access corridors. The FTP includes BMPs to manage public access, including signage, detours, monitors or

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flaggers, and temporary exclusionary fencing. Phasing and scheduling measures would be implemented to minimize the duration and extent of any temporary closures (Recreation Resources BMP-1-6).

Emergency response services within the Project area are provided by the Santee Fire Department, the San Diego County Sheriff's Department, and other responsible agencies. The City of Santee participates in the County’s emergency planning framework, including the San Diego County Emergency Operations Plan, which establishes evacuation procedures and identifies major interstates and arterial roadways as primary evacuation routes.

The Project does not include permanent road closures, structural development, or land use changes that would restrict established evacuation routes or emergency access corridors. Temporary access controls associated with vegetation treatment and maintenance activities would be localized, short term, and coordinated to avoid interference with emergency response needs. Emergency access would be maintained to the extent feasible during Project implementation.

The primary purpose of the Project is hazard mitigation and fuels reduction, which would reduce wildfire ignition potential and fire intensity within the corridor and improve emergency response conditions in proximity to developed areas. Although temporary access restrictions could result in short-term inconvenience for recreational users, the Project includes access planning and public safety measures and does not propose permanent closures or block emergency routes. By maintaining reduced fuel loads and fire risk, the Project would support emergency response and evacuation objectives rather than impair them.

Therefore, the Project would not physically interfere with the implementation of an adopted emergency response plan or emergency evacuation plan, and impacts would be less than significant.

G. Would the Project expose people or structures, either directly or indirectly, to a significant risk of loss, injury, or death involving wildland fires?
Portions of the Project Site are in areas designated as Moderate and High FHSZs and bordered by areas designated as Moderate, High, and Very High FHSZs to the north and south. These designations reflect existing wildfire risk conditions within and adjacent to the river corridor. The Project Site is located within a wildland–urban interface setting and is characterized by proximity to residential development and high levels of public access, which contribute to elevated ignition potential.

The proposed Project is designed to reduce hazardous fuel loads and fuel continuity through zone-based vegetation management prescriptions. The FTP documents recent ignition response activity by the Santee Fire Department within and near the river corridor and uses this information to support the need for vegetation treatment and hazard reduction. Project implementation would involve the use of mechanical equipment that could pose temporary ignition risks during active operations. However, the FTP includes fire prevention and protection BMPs, such as maintaining firefighting tools and water on site, use of spark arrestors, communication protocols for reporting ignitions, and restrictions on equipment operation during Red Flag Warning periods and other high fire danger conditions (Fire Protection BMPs 1-5). With implementation of these BMPs, operational ignition risks would be minimized. In the long term, the Project would reduce hazardous fuel loading and fuel continuity within the corridor and adjacent to developed areas, thereby lowering the potential for wildfire ignition and spread. By improving defensible space conditions and reducing fire intensity potential, the Project would enhance public and structural safety. Ongoing maintenance activities would occur as needed based on biannual inspections to maintain a reduction in wildfire hazard on the Project Site after the initial treatment of the Project Site.

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In the long term, the proposed vegetation management activities would reduce hazardous vegetation and wildfire intensity within the San Diego River corridor, thereby reducing potential wildfire-related risks to existing infrastructure. By lowering fire intensity and improving defensible space conditions, the Project would decrease the likelihood that wildfire could damage or compromise existing infrastructure.

Accordingly, the Project would not expose people or structures to an increased risk of loss, injury, or death related to wildland fires. Instead, the Project would result in a beneficial reduction in wildfire hazard.

Impacts would be less than significant.

4.3.5 Mitigation Measures and Level of Significance
After Mitigation
All impacts related to hazards and hazardous materials would be Iess than significant. No mitigation is required.

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4.4 Hydrology and Water Quality
This section describes the existing hydrology and water quality conditions of the San Diego River Fire Hazard Mitigation Plan: Fuels Treatment Plan Project (Project) Site and vicinity, identifies associated regulatory requirements, evaluates potential impacts, and identifies mitigation measures, if necessary, to reduce or avoid significant impacts related to implementation of the Project.

4.4.1 Existing Conditions
Watershed
The Project Site lies within the San Diego River Corridor in Santee. The corridor is in a broad alluvial valley with active and secondary channels, wetlands, and floodplain terraces within the San Diego River Watershed Management Area, San Diego Hydrologic Unit (907), and Santee Subwatershed (907.12) (San Diego RWQCB 2026). The San Diego River watershed originates in the mountains of east San Diego County, near Julian, and drains to the Pacific Ocean in Ocean Beach. The watershed encompasses 434 square miles. About 44% of the San Diego Watershed is undeveloped, 23% consists of open space and park, 19% is residential, 6% is for transportation uses, and 8% is for other uses. The San Diego River watershed supplies approximately 760,000 individuals with potable water. The watershed contains five reservoirs, including Lake Murray, Lake Jennings, San Vicente, El Capitan, and Cuyamaca Reservoirs, which are located in the eastern half of the San Diego River watershed, upstream from the Lower San Diego Hydrologic Area (Project Clean Water 2025).

The largest receiving water in the City is the San Diego River, which enters the City in the east and flows westward toward the Pacific Ocean. The City has five primary waterways: the San Diego River, Forester Creek, Sycamore Creek, and creeks paralleling Big Rock Road and Fanita Drive. All of the creeks have their own watersheds in addition to lying within the larger San Diego River watershed. All of these watersheds empty into the San Diego River, which flows westward into the Pacific Ocean (City of Santee 2003).

Water Quality
The State Water Resources Control Board (SWRCB) establishes statewide water quality control policies and regulations. The SWRCB also oversees the nine Regional Water Quality Control Boards (RWQCBs) in California, which are responsible for designating beneficial uses, establishing water quality objectives to protect those uses, and identifying programs of implementation to meet objectives through the preparation of a basin plan.

Beneficial Uses
The Water Quality Control Plan for the San Diego Basin (Basin Plan) lists beneficial uses of major water bodies within the region, including the San Diego River segment that comprises the Project Site. Within the Project Site, San Diego River is an inland surface water body with designated beneficial uses in the Basin Plan. Existing beneficial uses include municipal and domestic water supply, agricultural supply, industrial service supply, contact water recreation, non-contact water recreation, warm freshwater habitat, cold freshwater habitat, and wildlife habitat. The Basin Plan designates existing or potential beneficial uses for groundwater for the San Diego River Basin within the Project Site (San Diego RWQCB 2021).

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Groundwater
The San Diego River Watershed Management Area contains three groundwater basins: Mission Valley, San Diego River Valley, and El Cajon Valley. The Project Site overlies the San Diego River Valley Groundwater Basin, which consists of alluvium deposited by the San Diego River and its tributaries. The basin is surrounded by contacts with semi-permeable rocks of the Eocene Poway Group, impermeable Cretaceous crystalline rock, and impermeable Jurassic to Cretaceous Santiago Peak volcanic rocks. The Quaternary alluvium forms the principal water-bearing unit within the basin (DWR 2004).

Flood Hazards
The Project Site is located within portions of the San Diego River floodplain, which can experience periodic overbank flooding (FEMA 2026). As shown in Figure 4.4-1, Flood Hazard Map, the Project Site overlaps Federal Emergency Management Agency–designated flood hazard zones. Specifically, the Project Site includes zones designated as 1% annual chance of flood, regulatory floodway, and 0.2% chance of flood hazard.

Project Boundary
1% Annual Chance Flood Hazard
Regulatory Floodway

0.2% Annual Chance Flood Hazard
Date: 4/16/2026 User: cgardner Path: Z:\Projects\j1861101\MAPDOC\San Diego River Fire Hazard Mitigation Plan EIR\San Diego River Fire Hazard Mitigation Plan EIR.aprx Map: Flood Hazard Map Layout: 4.4-1 Flood Hazard Map 0 1,000 2,000 n Feet
SOURCE: Vantor 2026, FEMA 2026, USFWS 2026, USGS 2026
San Diego River Fire Hazard Mitigation Program EIR
Flood Hazard Map
FIGURE 4.4-1

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4.4.2 Relevant Plans, Policies, and Ordinances
Federal
Clean Water Act
The Clean Water Act (CWA), as amended by the Water Quality Act of 1987, is the major federal legislation governing water quality (33 USC 1251 et seq.). The objective of the CWA is “to restore and maintain the chemical, physical, and biological integrity of the Nation’s waters.” The CWA establishes basic guidelines for regulating discharges of both point and non-point sources of pollutants into the waters of the United States. The CWA requires that states adopt water quality standards to protect public health, enhance the quality of water resources, and ensure implementation of the CWA. Relevant sections of the CWA are as follows:
▪ Sections 303 and 304 provide for water quality standards, criteria, and guidelines. Under Section 303(d) of the CWA, the State of California is required to develop a list of impaired water bodies that do not meet water quality standards and objectives. California is required to establish total maximum daily loads (TMDLs) for each pollutant/stressor. A TMDL defines how much of a specific pollutant/stressor a given water body can tolerate and still meet relevant water quality standards. Once a water body is placed on the Section 303(d) List of Water Quality Limited Segments, it remains on the list until a TMDL is adopted and the water quality standards are attained or there is sufficient data to demonstrate that water quality standards have been met and delisting from the Section 303(d) list should occur. ▪ Section 401 (Water Quality Certification) requires an applicant for any federal permit that proposes an activity that may result in a discharge to waters of the United States to obtain certification from the state that the discharge will comply with other provisions of the CWA. This process is known as the Water Quality Certification/Waste Discharge Requirements process.
▪ Section 402 (National Pollutant Discharge Elimination System) establishes the National Pollutant Discharge Elimination System (NPDES), a permitting system for the discharge of any pollutant (except for dredged or fill material) into waters of the United States. This permit program is administered by the SWRCB and the nine RWQCBs, which have several programs that implement individual and general permits related to construction activities, stormwater runoff quality, and various kinds of non-stormwater discharges. ▪ Section 404 (Discharge of Dredged or Fill Material into Waters of the United States) establishes a permit program for the discharge of dredged or fill material into waters of the United States. This permit program is jointly administered by the U.S. Army Corps of Engineers (USACE) and the U.S. Environmental Protection Agency (EPA).

Numerous agencies have responsibilities for administration and enforcement of the CWA. At the federal level this includes EPA, USACE, the Bureau of Reclamation, and the major federal land management agencies, such as the U.S. Forest Service and the Bureau of Land Management. At the state level, with the exception of tribal lands, the California Environmental Protection Agency and its sub-agencies, including the SWRCB, have been delegated primary responsibility for administering and enforcing the certain provisions of the CWA in California. At the local level, the San Diego RWQCB, municipalities, and special districts have implementation and enforcement responsibilities under the CWA.

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Federal Antidegradation Policy
The federal Antidegradation Policy (40 CFR 131.12) is designed to protect water quality and water resources. The policy requires states to develop statewide antidegradation policies and identify methods for implementing those policies. State antidegradation policies and implementation measures must include the following provisions: (1) existing instream uses and the water quality necessary to protect those uses shall be maintained and protected; (2) where existing water quality is better than necessary to support fishing and swimming conditions, that quality shall be maintained and protected unless the state finds that allowing lower water quality is necessary for important local economic or social development; and (3) where high-quality waters constitute an outstanding national resource, such as waters of national and state parks, wildlife refuges, and waters of exceptional recreational or ecological significance, that water quality shall be maintained and protected. State permitting actions must be consistent with the federal Antidegradation Policy.

California Toxics Rule
The California Toxics Rule is a federal regulation issued by EPA providing water quality criteria for potentially toxic constituents in receiving waters with human health or aquatic life designated uses in the State of California. EPA adopted the California Toxics Rule in 2000 to create legally applicable water quality criteria for priority toxic pollutants for inland surface waters, enclosed bays, and estuaries to protect human health and the environment for all purposes and programs under the CWA. The California Toxics Rule aquatic life criterion were derived using a CWA Section 304(a) method that produces an estimate of the highest concentration of substances in water that do not present a significant risk to the aquatic organisms in the water and their uses. The California Toxics Rule water quality criteria provide a reasonable and adequate amount of protection with only a small possibility of substantial overprotection or under protection.

State
Porter–Cologne Water Quality Control Act
The Porter–Cologne Water Quality Control Act (Porter–Cologne Act) (codified in the California Water Code, Section 13000 et seq.) is the primary water quality control law for California. Whereas the CWA applies to all waters of the United States, the Porter–Cologne Act applies to waters of the state,1 which includes isolated wetlands and groundwater in addition to federal waters. The Porter–Cologne Act grants the SWRCB and the nine RWQCBs power to protect water quality and is the primary vehicle for implementation of California’s responsibilities under the federal CWA. The Porter–Cologne Act also grants the SWRCB and the nine RWQCBs authority and responsibility to adopt plans and policies, to regulate discharges of waste to surface and groundwater, to regulate waste disposal sites, and to require cleanup of discharges of hazardous materials and other pollutants. Further, the Porter–Cologne Act establishes reporting requirements for unintended discharges of any hazardous substance, sewage, or oil or petroleum product.

The act requires a “Report of Waste Discharge” for any discharge of waste (liquid, solid, or otherwise) to land or surface waters that may impair a beneficial use of surface or groundwater of the state. California Water Code Section 13260(a) requires that any person discharging waste or proposing to discharge waste, other than to a community sewer system, that could affect the quality of the waters of the state, to file a Report of Waste Discharge with the applicable RWQCB. For discharges directly to surface water (waters of the United States), an NPDES permit 1 “Waters of the state” are defined in the Porter–Cologne Act as “any surface water or groundwater, including saline waters, within the boundaries of the state” (California Water Code Section 13050[e]).

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is required, which is issued under both state and federal law; for other types of discharges, such as waste discharges to land (e.g., spoils disposal and storage), erosion from soil disturbance, or discharges to waters of the state (such as groundwater and isolated wetlands), waste discharge requirements (WDRs) are required and are issued exclusively under state law. WDRs typically require many of the same best management practices (BMPs) and pollution control technologies as required by NPDES-derived permits.

California Antidegradation Policy
The California Antidegradation Policy, otherwise known as the Statement of Policy with Respect to Maintaining High Quality Water in California, was adopted by the SWRCB (State Board Resolution No. 68-16) in 1968. Unlike the federal Antidegradation Policy, the California Antidegradation Policy applies to all waters of the state, not just surface waters. The policy requires that, with limited exceptions, whenever the existing quality of a water body is better than the quality established in individual basin plans (see description below), such high quality must be maintained, and discharges to that water body must not unreasonably affect any present or anticipated beneficial use of the water resource.

Water Quality Control Plan for the San Diego Basin
The California legislature has assigned the primary responsibility to administer and enforce statutes for the protection and enhancement of water quality, including the Porter–Cologne Act and portions of the CWA, to the SWRCB and its nine RWQCBs. The San Diego RWQCB implements the Basin Plan (San Diego RWQCB 2021), which designates beneficial uses, establishes water quality objectives, and contains implementation programs and policies to achieve those objectives for all waters addressed through the plan (California Water Code Sections 13240–13247). The Porter–Cologne Act also provides the RWQCBs with authority to include within their basin plan water discharge prohibitions applicable to particular conditions, areas, or types of waste. The Basin Plan is continually updated to include amendments related to implementation of TMDLs, revisions of programs and policies within the San Diego RWQCB Region, and changes to beneficial use designations and associated water quality objectives. The Basin Plan is the guiding document that establishes water quality standards for the region.

The basin plan for each region provides quantitative and narrative criteria for a range of water quality constituents applicable to certain receiving water bodies and groundwater basins within the region. Specific criteria are provided for the larger, designated water bodies within the region, as well as general criteria or guidelines for ocean waters, bays, and estuaries; inland surface waters; and groundwaters. In general, the narrative criteria require that degradation of water quality not occur due to increases in pollutant loads that will adversely impact the designated beneficial uses of a water body.

Construction General Permit
For stormwater discharges associated with construction activity in the State of California, the SWRCB has adopted the General Permit for Storm Water Discharges Associated with Construction and Land Disturbance Activities (Construction General Permit [CGP]) (Order No. 2022-0057-DWQ) to avoid and minimize water quality impacts attributable to such activities. The CGP applies to all projects in which construction activity disturbs one acre or more of soil. Construction activity subject to this permit includes clearing, grading, and disturbances to the ground, such as stockpiling and excavation. The CGP requires the development and implementation of a Stormwater Pollution Prevention Plan, which would specify water quality BMPs designed to reduce or eliminate pollutants in stormwater discharges and authorized non-stormwater discharges from the construction site. Routine inspection

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of all BMPs is required under the provisions of the CGP and the Stormwater Pollution Prevention Plan must be prepared and implemented by qualified individuals as defined by the SWRCB.

To receive coverage under the CGP, a project applicant must submit a Notice of Intent and permit registration documents to the SWRCB. Permit registration documents include a construction site risk assessment to determine appropriate coverage level; detailed site maps showing disturbance area, drainage area, and BMP types/locations; the Stormwater Pollution Prevention Plan; and, where applicable, post-construction water balance calculations and active treatment systems design documentation.

Phase II Small Municipal Separate Storm Sewer System Permit To enable efficient permitting under both the CWA and the Porter–Cologne Act, the SWRCB and the RWQCBs administer permit programs that group similar types of activities with similar threats to water quality. These “general permit” programs include the Phase II Small Municipal Separate Storm Sewer System (MS4) Permit, the CGP, and other general permits for low-threat discharges. Although the Phase ll Small MS4 Permit applies to small municipal storm sewer systems, the City of Santee is subject to Phase I MS4 Permits (Order No. R9-2013-0001, as amended by Order Nos. R9-2015-0001 and R9-2015-0100, NPDES No. CAS019266).

The Small MS4 Permit consists of several program elements: Program Management, Public Involvement/ Participation, Illicit Discharge Detection and Elimination, Construction Site Storm Water Runoff Control, Pollution Prevention/Good Housekeeping for Permittee Operations, Post Construction Storm Water Management for New Development and Re-development, Water Quality Monitoring Requirements, Program Effectiveness Assessment, and Annual Reporting. Besides requiring implementation of construction site BMPs and performance criteria and design guidelines for development within the Small MS4’s service area, the Small MS4 Permit also requires operators to map their outfalls, properly maintain the storm drain system, educate the public on pollution prevention, and monitor and report on the quality of MS4 discharges to receiving waters so that the effectiveness of the program can be evaluated. Collectively, the program elements are designed to ensure discharges from the storm drain system do not contain pollutant loads at levels that violate water quality standards and Basin Plan objectives and policies (such as a TMDL for a CWA Section 303[d] impaired water body). Implementation of the program elements are the responsibility of the Small MS4 operator, in this case, the City.

The Small MS4 Permit is administered by the SWRCB, while other general WDRs are administered by the San Diego RWQCB. Point source discharges or other activities that threaten water quality that are not covered under a general permit must seek individual NPDES permits and/or WDRs, depending on the type, location, and destination of the discharge. For these types of discharges, the initial step in the process is to submit a “Report of Waste Discharge” to the San Diego RWQCB, which then determines the appropriate permitting pathway.

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Local
City of Santee General Plan
The Conservation, Safety and Community Enhancement Elements of the Santee General Plan contain objectives and policies related to the protection of water corridors within the City, as listed below:

Conservation Element
Objective 2.0 Protect floodways to reduce flood hazards, protect biological resources and preserve the aesthetic quality along water corridors.

Policy 2.1 The City shall encourage the protection of the San Diego River Corridor and all other City water corridors to reduce flood hazards, protect significant biological resources and scenic values, and to provide for appropriate recreational uses.

Policy 2.6 The City encourages the development of appropriate flood control measures to assure public safety, which also prioritize maintenance of natural habitats and vegetation, and provision of community recreational opportunities as feasible and appropriate.

Policy 2.7The City shall ensure that all development proposals are located outside of designated floodways and all development in the 100-year floodplain is consistent with the City’s Flood Damage Protection Ordinance.

Safety Element
Objective 1.0 Minimize injuries, loss of life and property damage resulting from flood hazards.

Community Enhancement Element
Objective 16.0 Utilize the natural design elements presented by the river/creek system within the City.

Policy 16.1 The City should encourage the strengthening of links between the San Diego River, Forester Creek, Woodglen Vista Creek and the Sycamore Creek/Santee Lakes.

Policy 16.4 The City shall respect the natural stream processes of the San Diego River and its tributaries and ensure that flood control improvements along existing watercourses/channels avoid concrete channelization whenever possible and retain the natural character of the corridor through planting or preservation of native vegetation.

4.4.3 Thresholds of Significance
The significance criteria used to evaluate the Project’s impacts to hydrology and water quality are based on Appendix G of the California Environmental Quality Act (CEQA) Guidelines. According to CEQA Guidelines Appendix G, a significant impact related to hydrology and water quality would occur if the Project would incur the following:

Violate any water quality standards or waste discharge requirements or otherwise substantially degrade surface or groundwater quality.

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Substantially decrease groundwater supplies or interfere substantially with groundwater recharge such that the Project may impede sustainable groundwater management of the basin.

Substantially alter the existing drainage pattern of the site or area, including through the alteration of the course of a stream or river or through the addition of impervious surfaces, in a manner which would:

I. result in substantial erosion or siltation on or off-site; II. substantially increase the rate or amount of surface runoff in a manner which would result in flooding on or off-site;
III. create or contribute runoff water which would exceed the capacity of existing or planned stormwater drainage systems or provide substantial additional sources of polluted runoff; or IV. impede or redirect flood flows.

In flood hazard, tsunami, or seiche zones, risk release of pollutants due to project inundation.

Conflict with or obstruct implementation of a water quality control plan or sustainable groundwater management plan.

4.4.4 Impact Analysis
A. Would the Project violate any water quality standards or waste discharge requirements or otherwise substantially degrade surface or groundwater quality?
The Project Site contains surface water features, including the San Diego River and adjacent wetland and floodplain areas, which currently experience natural flows. The Project would include manual, mechanical, and chemical treatments (EPA-approved herbicides). Heavy equipment, and worker activity, could result in erosion and mobilize sediments adjacent to the San Diego River. Additionally, herbicides, and accidental release or fuels/lubricants from equipment have the potential to enter the San Diego River and surrounding wetlands. The Project would implement BMPs that would avoid herbicide application during wet conditions (Chemical BMP-3), implement erosion and sediment control measures (Slope Stability/Erosion BMP-1-10), and ensure proper maintenance of equipment (Chemical BMP-1 and Air Quality BMP-2). The Project would not violate water quality standards or WDRs and would not substantially degrade surface water or groundwater quality. Therefore, impacts are less than significant.

B. Would the Project substantially decrease groundwater supplies or interfere substantially with groundwater recharge such that the Project may impede sustainable groundwater management of the basin? The Project would involve vegetation management activities that include selective hand labor, limited mechanical access, trimming, and removal of non-native or dead vegetation. Water use for vegetation management would be limited to temporary activities such as dust suppression associated with treatments and maintenance of the Project Site. Water would be hauled on site by the Project contractor and would not initiate new groundwater extractions or increase the Padre Dam Municipal Water District overall pumping capacity. The Project would not introduce any new impervious surfaces as part of Project implementation. Temporary crew access and equipment use would not meaningfully compact soils that would result in decreased groundwater recharge. The Project would not extract groundwater, change recharge conditions, and introduce any activity that would decrease groundwater supplies or interfere with groundwater recharge, or could interfere with the sustainable management of the basin. Therefore, groundwater- related impacts would be less than significant.

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C. Would the Project substantially alter the existing drainage pattern of the site or area, including through the alteration of the course of a stream or river or through the addition of impervious surfaces, in a manner which would:
i) result in substantial erosion or siltation on or off-site; ii) substantially increase the rate or amount of surface runoff in a manner which would result in flooding on or off site;
iii) create or contribute runoff water which would exceed the capacity of existing or planned stormwater drainage systems or provide substantial additional sources of polluted runoff; or iv) impede or redirect flood flows?
The Project Site contains the San Diego River and adjacent wetland and floodplain areas, which is largely pervious. The San Diego River and its adjacent floodplain comprise the Project Site. The San Diego River experiences periodic overbank flows during storm events (FEMA 2026). The Project would involve vegetation management activities that include removal of non-native, invasive dead/dying vegetation, as well as trimming, thinning, and debris removal within the San Diego River corridor. The amount of vegetation removed would vary based on the distance from the closest structure and the level of prior treatment. After the initial treatment, biannual inspections will occur to determine maintenance needs across the Project Site. Zone 1 would experience the most vegetation removal, while Zone 3, which is generally closest to the river, would experience the least. These activities have the potential to disturb soil through foot traffic, equipment movement, and removal of surface vegetation. The Project does not propose the introduction of impervious surfaces or the alteration of the river. Soil disturbance and removal of vegetation have the potential to increase the susceptibility to erosion and change the hydrology of an area. However, the Project would implement erosion prevention BMPs, including retaining root systems (no grubbing), maintaining non-invasive groundcover, avoiding activity during saturated soil conditions, and using erosion control BMPs where soft soils cannot be avoided (Slope Stability/Erosion-BMP-1-10). These measures would help prevent rutting and compaction, further reducing changes to infiltration or runoff rates. Impacts would be less than significant by including BMPs that would reduce erosion, siltation, and on- or off-site flooding, and impede or redirect flood flows.

Vegetation management activities would introduce crews and small equipment including fuels, lubricants, and other materials that could act as pollutants into an area that currently does not contain such equipment. As described in Section 4.3, Hazards and Hazardous Materials, BMPs have been identified to reduce potential for pollutants to enter waterways (Hand Labor BMP-6. Water Quality BMP-1-5, Mechanical BMP-16, Chemical BMP-1-11). As a result, the Project would not exceed drainage system capacity or create polluted runoff and impacts would be less than significant.

D. Would the Project in flood hazard, tsunami, or seiche zones, risk release of pollutants due to project inundation? The proposed Project lies within an inland river corridor and is not in a tsunami or seiche zone (CGS 2026).

Portions of the Project Site lie within the San Diego River floodplain and may experience periodic flooding during high flow events (FEMA 2026). Vegetation management activities would involve the use of equipment that contain pollutants. As described in Section 4.3, BMPs have been identified to reduce potential for pollutants to enter waterways (Hand Labor BMP-6, Water Quality BMP-1-5, Mechanical BMP-16, and Chemical BMP-1-11). More specifically, the Project would implement stabilization BMPs that

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would include avoidance of hydroseed application when local rainfall greater than 0.5 inches is forecast within 24 hours of planned application (Chemical BMP-3) to prevent the release of pollutants if flooding were to occur within the Project Site. Work would be suspended during/after significant rainfall and would avoid saturated soils to prevent disturbance and pollutant transport. With these measures in place, vegetation management activities would not risk the release of pollutants during flood conditions, and the impact would be less than significant.

E. Would the Project conflict with or obstruct implementation of a water quality control plan or sustainable groundwater management plan?
The Project Site is subject to the Water Quality Control Plan for the San Diego Basin (Basin Plan), which establishes beneficial uses, water quality objectives, and implementation programs for inland surface waters and groundwater in Region 9, including the San Diego River (SWRCB 2021). The Project consists of vegetation management activities and would not include grading, excavation, channel modification, or inchannel work. The Project would implement BMPs to prevent pollutants from reaching the San Diego River, including sediment and perimeter controls, staging/refueling outside drainages with containment and spill kits, routine equipment inspections, removal of cut biomass from jurisdictional areas, avoiding saturated soils, and suspending work during/after significant rainfall (Hand Labor BMP-6, Water Quality BMP-1-5, Mechanical BMP-15, and Chemical BMP-1-11). These measures ensure the Project’s activities avoid discharges into the river or altering water quality. The Project would not require extraction of groundwater, thereby preserving infiltration and avoiding changes to recharge. Based on these Project elements, the Project would not include actions that would interfere with groundwater conditions or management.

With implementation of the Project’s BMPs, the Project would not conflict with the Water Quality Control Plan for the San Diego Basin (SWRCB 2021). The Project would not obstruct implementation of a groundwater sustainability plan. (SDCWA 2026; SWRCB 2026). Therefore, the Project would not conflict with or obstruct implementation related to water quality protection or groundwater sustainability. Impact would be less than significant.

4.4.5 Mitigation Measures and Level of Significance
After Mitigation
All impacts related to hydrology and water quality would be less than significant. No mitigation is required.

4.5 – NOISE
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4.5 Noise
This section describes the existing noise conditions of the Santee River Fire Hazard Mitigation Program: Fuels Treatment Plan (Project) Site and vicinity, identifies associated regulatory requirements, evaluates potential impacts, and identifies mitigation measures, if necessary to reduce or avoid significant impacts, related to implementation of the Project.

4.5.1 Existing Conditions
Noise and Vibration Characteristics
Noise
Sound may be described in terms of level or amplitude (measured in decibels [dB]), frequency or pitch (measured in hertz or cycles per second), and duration (measured in seconds or minutes). The standard unit of measurement of the amplitude of sound is the decibel. Because the human ear is not equally sensitive to sound at all frequencies, a special frequency-dependent rating scale is used to relate noise to human sensitivity. The Aweighted decibel scale (dBA) performs this compensation by discriminating against low and very high frequencies in a manner approximating the sensitivity of the human ear. Several descriptors of noise (noise metrics) exist to help predict average community reactions to the adverse effects of environmental noise, including trafficgenerated noise, on a community. These descriptors include the equivalent noise level over a given period (Leq), the statistical sound level, the day–night average noise level (Ldn), and the Community Noise Equivalent Level (CNEL). Each of these descriptors uses units of dBA. Table 4.5-1 provides examples of A-weighted noise levels from common sounds. In general, human sound perception is such that a change in sound level of 3 dB is barely noticeable; a change of 5 dB is clearly noticeable; and a change of 10 dB is perceived as doubling or halving of the sound level (Caltrans 2013).

The Leq descriptor is a sound level energy-averaged over a specified period (typically no less than 15 minutes for environmental studies). It is a single and constant numerical value that represents the equivalent amount of variable sound energy received by a receptor during a time interval. For example, a 1-hour Leq value of 55 dBA could represent the measured constant sound of 55 dBA from a continuous source of emission (e.g., steady-state operation of electro-mechanical equipment) or the logarithmic average of time-varying measured sound energy contained in that hour. The Leq value is therefore a common and effective noise descriptor because of its ability to assess the total time-varying effects of noise on sensitive receptors. The Lmax value is the maximum sound level measured during a designated time interval or event.

Unlike the Leq metrics, Ldn and CNEL metrics always represent 24-hour periods, usually on an annualized basis. Ldn and CNEL also differ from Leq because they apply a time-weighted factor designed to emphasize noise events that occur during the evening and nighttime hours (when speech and sleep disturbance is of more concern). “Time weighted” refers to the fact that Ldn and CNEL penalize noise that occurs during certain sensitive periods. In the case of CNEL, noise occurring during the daytime (7:00 a.m.–7:00 p.m.) receives no penalty. Noise during the evening (7:00 p.m.–10:00 p.m.) is penalized by adding 5 dB, while nighttime (10:00 p.m.–7:00 a.m.) noise is penalized by adding 10 dB. Ldn differs from CNEL in that the daytime period is defined as 7:00 a.m.–10:00 p.m., thus eliminating the evening period. Ldn and CNEL are the predominant criteria used to measure roadway noise affecting residential receptors. These two metrics generally differ from one another by no more than 0.5 dB to 1 dB, and as such are often treated as equivalent to one another.

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Table 4.5-1. Typical Sound Levels in the Environment and Industry Common Outdoor Activities
Noise Level
(dBA) Common Indoor Activities
— 110 Rock band
Jet flyover at 300 meters (1,000 feet) 100 N/A
Gas lawn mower at 1 meter (3 feet) 90 N/A
Diesel truck at 15 meters (50 feet), at 80 kph
(50 mph)
80 Food blender at 1 meter (3 feet)
Garbage disposal at 1 meter (3 feet)
Noisy urban area, daytime
gas lawn mower at 30 meters (100 feet)
70 Vacuum cleaner at 3 meters (10 feet)
Commercial area
Heavy traffic at 90 meters (300 feet)
60 Normal speech at 1 meter (3 feet)
Quiet urban daytime 50 Large business office
Dishwasher, next room
Quiet urban nighttime 40 Theater, large conference room (background)
Quiet suburban nighttime 30 Library
Quiet rural night time 20 Bedroom at night, concert hall (background)
— 10 Broadcast/recording studio
Lowest threshold of human hearing 0 Lowest threshold of human hearing Source: Caltrans 2013.

Notes: dBA = A-weighted decibels; N/A = not applicable; kph = kilometers per hour; mph = miles per hour.

Vibration
Vibration is an oscillatory motion through a solid medium in which the motion’s amplitude can be described in terms of displacement, velocity, or acceleration. At sufficient magnitudes, vibration can be a serious concern, causing buildings to shake and rumbling sounds to be heard. In contrast to noise, vibration is not a common environmental problem. It is unusual for vibration from sources such as buses and trucks to be perceptible, even in locations close to major roads (FTA 2018). Some common sources of vibration are trains, buses on rough roads, and construction activities, such as blasting, pile driving, and heavy earthmoving equipment.

Several different methods are used to quantify vibration. Peak particle velocity (PPV) is defined as the maximum instantaneous peak of the vibration signal. PPV is most frequently used to describe vibration impacts to buildings and is usually measured in inches per second (ips); however, it can also be used to evaluate potential effects to building occupants (i.e., quantifying annoyance due to perceived vibration). A root mean square amplitude is frequently used to describe the effect of vibration on the human body and is defined as the average of the squared amplitude of the signal. Vibration velocity decibel notation is commonly used to describe root mean square vibration and relates to PPV by means of a crest factor (FTA 2018).

High levels of vibration may cause physical personal injury or damage to buildings. However, vibration levels rarely affect human health. Instead, most people consider vibration to be an annoyance that can affect concentration or disturb sleep. In addition, high levels of vibration can damage fragile buildings or interfere with equipment that is highly sensitive to vibration (e.g., electron microscopes). Most perceptible indoor vibration is caused by sources within buildings, such as operation of mechanical equipment, movement of people, or slamming of doors. Typical

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outdoor sources of perceptible vibration are construction equipment, steel-wheeled trains, and traffic on rough roads. If the roadway is smooth, the vibration from traffic is rarely perceptible.

Sensitive Receptors
Noise- and vibration-sensitive land uses are locations where people reside or where the presence of unwanted sound could adversely affect the use of the land. Residences, schools, hospitals, guest lodging, libraries, and some passive recreation areas would be considered noise and vibration sensitive and may warrant unique measures for protection from intruding noise.

The Project Site is surrounded mostly by residential and commercial uses. The closest sensitive receptors to the Project Site are the existing residences that are approximately 20 feet from the Project Site boundary.

Existing Noise Conditions
The San Diego River Corridor in the City consists of a mixture of natural riparian habitat, public parkland, transportation corridors, and adjacent commercial and residential development. Existing ambient noise levels in this part of the City are shaped primarily by transportation sources, with intermittent contributions from recreational activity, aircraft flyovers associated with Gillespie Field, commercial operations, and construction associated with ongoing development. As a means of coarsely estimating the existing outdoor ambient sound level at a location of interest, one may refer to Figure 7-2 of the Noise Element (i.e., Chapter 7) of the City of Santee General Plan (City of Santee 2003), which illustrates both Gillespie Field aviation noise contours and major roadway transportation noise contours emanating from these sound emission sources across the City and portions of the Project area.

4.5.2 Relevant Plans, Policies, and Ordinances
Federal
Federal Transit Administration
In its Transit Noise and Vibration Impact Assessment guidance manual, the Federal Transit Administration (FTA) recommends a daytime construction noise level threshold of 80 dBA Leq over an 8-hour period (FTA 2018) when detailed construction noise assessments are performed to evaluate potential impacts to community residences surrounding a project. Although this FTA guidance is not a regulation, it can serve as a quantified standard in the absence of such noise limits at the state and local jurisdictional levels.

Federal Interagency Committee on Noise
Some guidance regarding the determination of a substantial permanent increase in ambient noise levels in the project vicinity above existing levels is provided by the 1992 findings of the Federal Interagency Committee on Noise (FICON 1992), which assessed the annoyance effects of changes in ambient noise levels resulting from aircraft operations. The Federal Interagency Committee on Noise recommendations are based upon studies that relate aircraft and traffic noise levels to the percentage of persons highly annoyed by the noise. Annoyance is a qualitative measure of the adverse reaction of people to noise that generates speech interference, sleep disturbance, or interference with the desire for a tranquil environment.

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The rationale for the Federal Interagency Committee on Noise recommendations is that it is possible to consistently describe the annoyance of people exposed to transportation noise in terms of Ldn. The changes in noise exposure that are shown below are expected to result in equal changes in annoyance at sensitive land uses. Although the Federal Interagency Committee on Noise recommendations were specifically developed to address aircraft noise impacts, they are used in this analysis to define a substantial increase in community noise levels related to all transportation noise sources and permanent non-transportation noise sources. ▪ Outdoor ambient sound level without the project is less than 60 dBA Ldn, then a project-attributed increase of 5 dBA or more would be considered significant.
▪ Outdoor ambient sound level without the project is between 60 and 65 dBA Ldn, project-attributed increase of 3 dBA or more would be considered significant.
▪ Outdoor ambient sound level without the project is greater than 65 dBA Ldn, then project-attributed increase of 1.5 dBA or more would be considered significant.

State
California Code of Regulations, Title 24
Title 24 of the California Code of Regulations sets standards that new developments in California must meet.

According to Title 24, interior noise levels are not to exceed 45 dBA CNEL in any habitable room (ICC 2019).

California Department of Health Services Guidelines
The California Department of Health Services has developed guidelines of community noise acceptability for use by local agencies (OPR 2017). Selected relevant levels are listed here:
▪ Below 60 dBA CNEL: normally acceptable for low-density residential use ▪ 50 to 70 dBA CNEL: conditionally acceptable for low-density residential use ▪ Below 65 dBA CNEL: normally acceptable for high-density residential use and transient lodging ▪ 60 to 70 dBA CNEL: conditionally acceptable for high-density residential, transient lodging, churches, educational, and medical facilities
The normally acceptable exterior noise level for high-density residential use is up to 65 dBA CNEL. Additionally, this exterior noise level limit is consistent with the City of Santee General Plan Noise Element, which considers multifamily unit noise-sensitive land uses.

California Department of Transportation
In its Transportation and Construction Vibration Guidance Manual (Caltrans 2020), the California Department of Transportation (Caltrans) recommends 0.5 ips PPV as a threshold for the avoidance of structural damage to typical newer residential buildings exposed to continuous or frequent intermittent sources of groundborne vibration. For transient vibration events, such as blasting, the damage risk threshold would be 1.0 ips PPV (Caltrans 2020) at the same type of newer residential structures. For older structures, these guidance thresholds would be more stringent:

0.3 ips PPV for continuous/intermittent vibration sources, and 0.5 ips PPV for transient vibration events. With respect to human annoyance, Caltrans guidance indicates that building occupants exposed to continuous groundborne vibration of 0.2 ips PPV would find it “annoying” and thus a likely significant impact. Although these

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Caltrans guidance thresholds are not regulations, they can serve as quantified standards in the absence of such limits at the local jurisdictional level.

Local
City of Santee General Plan
City of Santee Noise Level Compatibility Standards
The Noise Element of the City’s General Plan (City of Santee 2003) establishes target maximum noise levels in the City, categorized by land use. The Noise Element sets the following limitations on noise levels for receiving properties adjacent to the Project Site.

Transportation-Related Noise Standards
The City’s Noise Element establishes a policy for exterior sensitive areas to be protected from high traffic noise levels. The Noise Element sets 65 dBA Ldn for exterior noise levels and 45 dBA Ldn for interior noise levels as the “normally acceptable” level.

For interior noise, the Noise Element also establishes 45 dBA Ldn as the maximum acceptable level for habitable rooms when exterior predicted noise levels due to traffic are 65 dBA Ldn or more. If windows and doors are required to be closed to meet this standard, then mechanical ventilation (i.e., air conditioning) shall be included in the Project design.

Noise Element
The Noise Element contains a section on the noise abatement and control objectives and policies for the City; relevant objectives and policies are presented below.

Objective 1.0 Control noise from sources adjacent to residential, institutional and other noise-sensitive receptors.

Policy 1.6 The City shall continue to monitor noise throughout Santee and enforce the standards and regulations of the City’s Noise Ordinance.

Policy 1.16 The City shall ensure that appropriate regulations and standards are incorporated into the City’s development policies and ordinances, including the use of noise evaluations in Environmental Impact Reports and statements, which take all aspects of noise into consideration.

Policy 1.17 The City shall officially support the control of noise through legal regulations and cooperative government efforts.

City of Santee Noise Ordinance
Construction activities are subject to Section 5.04.090 of the City’s Noise Ordinance, which specifically prohibits the operation of any single or combination of powered construction equipment at any construction site on Mondays through Thursdays except between the hours of 7:00 a.m. and 7:00 p.m. Further, construction equipment with a manufacturer’s noise rating of 85 dBA Lmax or greater may only operate at a specific location for 10 consecutive

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workdays. A notice must be provided to all property owners within 300 feet if work is scheduled for more than 10 days and must be provided no later than 10 days prior to the start of the construction.

Municipal Code Section 5.04.160 applies to any noise source not specifically addressed in this chapter, except where exempted or excluded by Section 5.04.170. This section states that it is unlawful for any person to generate any noise on the public way that is louder than average conversational level at a distance of 50 feet or more, vertically or horizontally, from the source between 10:00 p.m. and 7:00 a.m. Also, between 10:00 p.m. and 7:00 a.m., no person is permitted to generate any noise on any private open space that is louder than average conversational level at a distance of 50 feet or more, measured from the property line of the property from which the noise is being generated.

4.5.3 Thresholds of Significance
The significance criteria used to evaluate the Project impacts related to noise are based on California Environmental Quality Act (CEQA) Appendix G. According to CEQA Guidelines Appendix G, a significant impact related to noise would occur if the Project would:

A. Generate a substantial temporary or permanent increase in ambient noise levels in the vicinity of the Project in excess of standards established in the local general plan or noise ordinance, or applicable standards of other agencies.

B. Generate excessive groundborne vibration or groundborne noise levels.

C. For a project located within the vicinity of a private airstrip or an airport land use plan or, where such a plan has not been adopted, within two miles of a public airport or public use airport, expose people residing or working in the Project area to excessive noise levels.

4.5.4 Impact Analysis
A. Would the Project generate a substantial temporary or permanent increase in ambient noise levels in the vicinity of the Project in excess of standards established in the local general plan or noise ordinance, or applicable standards of other agencies?
Noise associated with the initial treatment and maintenance of vegetation would primarily come from use of equipment. Noise from vegetation management activities are temporary and would vary hour to hour and day to day depending on the equipment in use, the operations performed, and the distances between these multiple sources of noise emission and a receptor of interest having a fixed location. The typical equipment used for each noise-generating treatment activity is summarized in Table 4.5-2 below. The typical maximum noise levels at a distance of 50 feet from various pieces of construction equipment and activities anticipated for use on the proposed Project Site are presented in Table 4.5-3. Note that the equipment noise levels presented in Table 4.5-3 are maximum noise levels. Usually, construction equipment operates in alternating cycles of full power and low power, producing average noise levels over time that are less than the maximum noise level. The average sound level of construction activity also depends on the amount of time that the equipment operates and the intensity of construction activities during that time. In fact, the Federal Highway Administration Roadway Construction Noise Model, from which the values in Table 4.5-3 are referenced, applies an “acoustical usage factor” to define the latter.

This acoustical usage factor value, a percentage that may be as low as 16% for a crane that works briefly under load, and as high as 100% for continuously operating stationary equipment like ventilation fans,

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refrigeration units, and pumps, is thus utilized to help derive a corresponding lower Leq value from the Lmax value appearing in Table 4.5-3 for each type of anticipated Project heavy equipment.

Table 4.5-2. Equipment by Vegetation Management Activity Vegetation Management Activity Equipment Types
Hand Labor Chainsaws, masticators, chippers
Mechanical Excavators, masticators, chippers, front-end loader, skid steer, air compressor
Typical construction equipment maximum noise levels are summarized in Table 4.5-3 below.

Table 4.5-3. Typical Construction Equipment Maximum Noise Levels Equipment Type Typical Equipment (Lmax, dBA at 50 Feet) Air Compressor 78
”All Other Equipment > 5 HP” (e.g., chipper)* 85
Excavator 81
Crane 81
Front-End Loader 79
Source: FHWA 2006. *meant to broadly cover unlisted equipment types.

Note: Lmax = maximum sound level; dBA = A-weighted decibels.

As shown in Table 4.5-3, noise levels generated by individual equipment range from 78 to 85 dBA Lmax at 50 feet from the noise source. Converted to an hourly Leq, and due to having acoustical usage factor values of 40% (FHWA 2006), the excavator and front-end loaders would be expected to exhibit noise emission of 77 dBA and 75 dBA, respectively. Though multiple pieces of equipment would be operated simultaneously to implement a treatment, they would typically be spread out (i.e., usually more than 100 feet apart) rather than operating next to each other. This is particularly true of larger, heavy-duty off-road equipment such as masticators, chippers, bulldozers, skid steers, and excavators. This helps ensure worker safety and maximizes efficiency.

As discussed in Chapter 3, Project Description, vegetation management within the Project Site would rely on a combination of techniques to reduce the potential for ignitions and modify fire behavior, including hand labor, mechanical, and chemical treatment. While the Fuels Treatment Plan allows for use of any vegetation management techniques in each zone, method selection would depend on site conditions, access availability/condition, target vegetation types, zone designation, proximity to sensitive resources, and the potential for soil or habitat disturbance in sensitive areas. The most noise-intensive vegetation treatment activity is the mechanical technique, which would require the use of motorized heavy equipment.

Chemical treatments would not require the use of heavy off-road equipment; noise generated by these treatment types would be minimal.

Although all pieces of heavy equipment could operate simultaneously for vegetation treatment activities under the Project, because of the size of the treatment zone sites and the spatial operational constraints of heavy equipment (only so many could operate in close proximity to one another because of function and size) it is unlikely that all pieces of equipment would operate in close proximity to each other near the boundaries of the Project Site. Therefore, it is unlikely that noise from multiple pieces of equipment would

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combine to adversely affect any noise-sensitive receptor for an extended period, such as with respect to the aforementioned FTA guidance-based threshold of 80 dBA 8-hour Leq at the exterior of an offsite residence.

An illustrative scenario that results in compliance with this FTA threshold, and thus a less-than-significant impact, would include the following parameters and be consistent with FTA “general assessment” technique for evaluating construction noise when site-specific details are unclear or undetermined:
▪ An excavator and front-end loader are working a full 8 hours at a site; and ▪ Over the course of this 8-hour workday or assessment period, horizontal distances between each of these two heavy equipment pieces and the off-site receiver are no closer than 45 feet.

Where the off-site noise-sensitive receiver may be closer to these pieces of operating equipment, such as only 17 feet, then compliance could still be expected so long as either of the following noise reduction techniques were applied:
▪ Administrative noise control – reduce equipment operation time to just 1 hour per 8-hour period; or ▪ Temporary noise abatement – install 8-foot-tall plywood sheet barriers (or acoustical blankets suspended on chain-link fencing or other support means) on or parallel with the Project boundary that adjoins the receiving noise-sensitive property.

The former “dilutes” the sound energy of the single hour across the 8-hour assessment period, and the latter blocks direct sound paths and thus attenuates the sound emission before it reaches the receiver position. Hence, should equipment-to-receiver horizontal distances be less than 45 feet, MM NOI-1 would apply either administrative noise controls or temporary noise abatement to yield receiver exposure levels that are predicted to be less than 80 dBA 8-hour Leq and thus a less-than-significant impact with mitigation.

Despite this finding, Project activity noise may cause outdoor ambient sound levels to be considerably higher than pre-existing or non-Project levels; for instance, if the outdoors of a residence near the Project area typically experiences 55 dBA Leq during daytime hours, Project vegetative management activity noise of nearly but not exceeding a magnitude of 80 dBA Leq would be a change of almost 25 dB and thus a clearly audible but temporary change to the outdoor sound environment.

In isolated or inaccessible areas where large trees cannot be safely removed using standard ground-based methods, helicopter or crane-assisted removal may be used. These techniques allow large trees to be lifted out without disturbing sensitive terrain or adjacent properties but require advance planning for safe lift paths, staging zones, and coordination with permitting agencies. Due to their cost and operational complexity, helicopter and crane removal would be considered only when no practical ground-based alternative exists. Due to the nature of these areas being inaccessible, it is assumed that noise-sensitive receptors would not be located in close proximity to the Project Site. However, noise-sensitive receptors could be exposed to helicopter noise during approach and takeoff procedures. The helicopter would only be used when no other practical alternatives exist; and thus, total helicopter usage for individual vegetation treatment sites would be limited to one helicopter trip over the span of 1 day and helicopter usage would be infrequent. Additionally, for safety and visibility reasons, helicopters would be used only during the day.

Therefore, any exposure of sensitive receptors to noise generated by helicopter activity would be brief, infrequent, and would not occur during noise-sensitive evening and nighttime hours.

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Furthermore, such a brief helicopter sortie (either passing by a receiver or involved in brief hover to perform a task) of partial hour duration and at safe elevation above grade would enable such noise exposure to be compliant with the aforementioned FTA-based guidance threshold of 80 dBA 8-hour Leq. By way of illustration, and aside from other activities in the vicinity, a helicopter exhibiting 105 dBA Lmax at a distance of 50 feet (per Federal Aviation Administration AC-36H data [FAA 2012]) and assuming 100% acoustical usage factor could operate as close as 225 feet (slant distance) to the receiver for up to 30 minutes. If more time was required, then the distance would need to be longer in order to attenuate the noise exposure at the receiver position.

In addition to the above, the Project would be required to comply with the ordinances for construction equipment outlined in Section 5.04.090 of the City’s municipal code, which includes limiting construction equipment use to Mondays through Saturdays between 7:00 a.m. and 7:00 p.m., and any construction equipment with a manufacturer’s noise rating of 85 dBA Lmax or greater can only operate at a specific location for 10 consecutive workdays without a notice provided to property owners. Therefore, implementation of Project mechanically supported vegetation treatment activities would not result in the exposure of noise-sensitive receptors to a substantial temporary increase in ambient noise levels.

As described above, if equipment would be located at a horizontal distance of less than 45 feet, there is potential for exposure levels to be greater than 80 dBA 8-hour Leq and mitigation would be required. MM NOI-1 would apply either administrative noise controls or temporary noise abatement to yield receiver exposure levels that are predicted to be less than 80 dBA 8-hour Leq and thus impacts would be less than significant with mitigation.

B. Would the Project generate excessive groundborne vibration or groundborne noise levels? Mechanical treatment associated with the Project would include some use of heavy motorized equipment, however, techniques that would cause excessive groundborne vibration or groundborne noise levels, such as pile driving or compaction activities, would not occur. Caltrans has collected groundborne vibration information related to construction activities (Caltrans 2020). Information from Caltrans indicates that continuous vibrations with a PPV of approximately 0.2 ips are considered annoying, and, with respect to “older residential structures,” a PPV of 0.3 ips would be considered a threshold for building damage risk.

For context, heavier pieces of construction equipment, such as a bulldozer that may be expected on the Project Site, have PPVs of approximately 0.089 ips or less at a reference distance of 25 feet.

Groundborne vibrations attenuate rapidly, even over short distances. The attenuation of groundborne vibration as it propagates from source to receptor through intervening soils and rock strata can be estimated with expressions found in FTA and Caltrans guidance. The closest residents to the Project Site are approximately 17 feet from the Project boundary. By way of example, for a bulldozer operating on site and as close as the Project boundary (17 feet from the nearest residence), the estimated vibration velocity would be 0.1587 ips per the equation as follows (FTA 2018):

PPVrcvr = PPVref * (25/D)1.5 = 0.1587 = 0.089 * (25/17)

1.5 In the above equation, PPVrcvr is the predicted vibration velocity at the receiver position, PPVref is the reference value at 25 feet from the vibration source (the bulldozer), and D is the actual horizontal distance to the receiver. The estimated groundborne vibration velocity level would be 0.1587 ips PPV as received by the residential structure and would be compliant with the 0.2 ips PPV threshold per Caltrans guidance with

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respect to annoyance. Additionally, at this predicted exposure of less than 0.3 ips PPV, the occupied residential structures would not experience a significant impact. Therefore, at this predicted PPV, the impact of vibration-induced building damage risk and annoyance to building occupants of nearby existing homes would be less than significant.

C. For a project located within the vicinity of a private airstrip or an airport land use plan or, where such a plan has not been adopted, within two miles of a public airport or public use airport, would the Project expose people residing or working in the Project area to excessive noise levels.

There are no private airstrips within the vicinity of the Project Site. The closest airport to the proposed Project Site is the Gillespie Field regional airport, approximately 1.1 miles south of the Project boundary.

According to the Gillespie Field Airport Land Use Compatibility Plan, the Project Site falls outside the studied noise contours (County of San Diego 2010). Impacts would be less than significant.

4.5.5 Mitigation Measures and Level of Significance
After Mitigation
MM NOI-1: Noise Reduction Techniques
Should mobile or stationary heavy construction equipment (i.e., self-propelled or electrically, mechanically, or hydraulically powered) associated with Project implementation operate at horizontal distances closer than 45 feet horizontal to an off-site noise-sensitive receiver position (e.g., exterior of an existing residence), the Project contractor(s) shall apply either of the following options as noise reduction techniques to keep noise exposures at or below the FTA guidance-based threshold (80 dBA 8-hour Leq during daytime hours):
▪ Administrative noise control – reduce heavy equipment operation time to just 1 hour per 8- hour period; or
▪ Temporary noise abatement – install 8-foot-tall (minimum height) plywood sheet barriers (or acoustical blankets suspended on chain-link fencing or other support means) along or parallel with an extent of the Project boundary that adjoins the receiving noise-sensitive property. The barrier extent shall have, end to end, a length of no less than the sum of the width of the property to be protected plus four times the perpendicular distance between it and the receiver position, where this perpendicular is extended from (or through) the midpoint of the receiving property line. Prior to the installation and use of temporary noise abatement, a qualified biologist shall confirm and verify with the City that the placement of the barriers are not located within any environmentally sensitive areas (e.g., special-status plant locations, sensitive vegetation communities, or jurisdictional aquatic resources) and would not impact any wildlife species or their movement.

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4.6 Wildfire
This section evaluates the effects of proposed San Diego River Fire Hazard Mitigation Program: Fuels Treatment Plan (Project) implementation on wildfire and wildfire-related risks. The following analysis considers drivers of wildfire risk, and how the proposed Project could add to such risk or expose people or structures to wildfire risk.

This section also describes the existing wildfire conditions of the Project Site and vicinity, identifies associated regulatory requirements, evaluates potential impacts, and identifies mitigation measures if necessary to reduce or avoid significant impacts related to implementation of the proposed Project.

4.6.1 Existing Conditions
Wildfire is a continuous threat in Southern California and is particularly concerning in the wildland–urban interface, the geographic area where urban development either abuts or intermingles with wildland or vegetative fuels. During the summer through the winter season, dry vegetation, prolonged periods of drought, and Santa Ana wind conditions can combine to increase the risk of wildfires in the County.

Fire History
The Project Site, like all of San Diego County, is subject to seasonal weather conditions that can heighten the likelihood of fire ignition and spread. Fire history is an important component of a wildfire analysis. Wildfire history information can provide an understanding of fire frequency, fire type, most vulnerable project areas, and significant ignition sources, among others. According to the permitter data available from CAL FIRE, no fires have been recorded at the Project Site since 1950 (CAL FIRE 2025a). However, the threshold for inclusion in the CAL FIRE’s perimeter database are fires measuring 10 acres in timber, 50 acres in brush, or 300 acres in grass. The Santee Fire Department (SFD) responded to 174 fires in or near the Project Site in 2024 and 2025. On March 29, 2026, an approximately 10-acre fire occurred within the Project Site. These fires are excluded from CAL FIRE’s fire perimeter database as they did not reach the aforementioned size threshold; however, they do emphasize the prevalence of wildfire risk in and around the City. The surrounding foothills also have a well-established fire history.

The most notable regional event was the 2003 Cedar Fire, which burned more than 273,000 acres and demonstrated the potential for large, wind-driven fires to spread rapidly from the east (RCD of Greater San Diego County and San Diego County Fire Safe Council 2019).

Across the San Diego Unit, CAL FIRE responds to approximately 510 wildland fires per year, with an average of 15,000 acres burned annually when the extreme fire-siege years of 2003 and 2007 are excluded (CAL FIRE 2025b).

Human-caused ignitions, including vehicle fires, debris burning, equipment use, and campfires, are the predominant ignition sources in the region (CAL FIRE 2025a). Given the San Diego River Corridor’s urban adjacency, recreational access, and history of use by unhoused populations in certain segments, ignitions within the Project Site are likely to arise from similar causes.

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Fire Hazard Mapping
CAL FIRE’s Fire and Resource Assessment Program database also includes map data documenting areas of significant fire hazards in the state. These maps categorize geographic areas of the state into different Fire Hazard Severity Zones (FHSZs), ranging from moderate to very high. CAL FIRE uses FHSZs to classify anticipated fire-related hazards for the entire state, and includes classifications for State Responsibility Areas, Local Responsibility Areas, and Federal Responsibility Areas. Fire hazard severity classifications take into account vegetation, topography, weather, crown fire production, and ember production and movement.

Vegetation Communities and Land Covers
Variations in vegetative cover type and species composition have a direct effect on fire behavior. Some plant communities and their associated plant species have increased flammability based on plant physiology (resin content), biological function (flowering, retention of dead plant material), physical structure (leaf size, branching patterns), and overall fuel loading.

A critical factor to consider is the dynamic nature of vegetation communities. Fire presence and absence at varying cycles or regimes affect plant community succession. Succession of plant communities, most notably the gradual conversion of shrublands to grasslands with high frequency fires and grasslands to shrublands with fire exclusion, is highly dependent on the fire regime. Further, biomass and associated fuel loading will increase over time if disturbance or fuel reduction effects are not diligently implemented.

The vegetation types and land covers in the Project Site were identified during field assessments conducted for the Project Site. As detailed in Section 4.1, Biological Resources, vegetation in the Project Site reflects the composition typical of inland valleys and river corridors in western San Diego County. Riparian vegetation, including willows, cottonwoods, mulefat, and associated understory species, dominates the immediate river margins. Although riparian vegetation often retains higher moisture levels, it can contain dense stands of shrubs, branches, and upstream debris from flooding, along with invasive species such as Arundo donax, which can contribute to elevated fire intensity (Eucalyptus Hills Fire Safe Council 2009). Non-native trees (palms, eucalyptus, tamarix, pines) also present a hazard, especially when dry branches form a fuel ladder and/or when they completely or partially detach from the canopy.

Upland terraces and disturbed areas support coastal sage scrub dominated by California sagebrush (Artemisia californica), black sage (Artemisia nova), and California buckwheat (Eriogonum fasciculatum), along with patches of non-native grasses that cure early in the fire season and readily carry surface fire. Mixed chaparral is present in the surrounding foothills but is less extensive within the 300-acre corridor itself. However, chaparral in adjacent uplands can influence ember production, wind-driven spread, and fire intensity during extreme weather events.

Topography/Terrain
Topography influences fire risk by affecting fire spread rates. Typically, steep terrain results in faster fire spread upslope and slower spread downslope. Terrain that forms a funneling effect, such as chimneys, chutes, or saddles on the landscape can result in especially intense fire behavior, including faster spread and higher intensity.

Conversely, flat terrain tends to have little effect on fire spread, resulting in fires that are driven by vegetation and wind. The Project Site occupies a broad alluvial valley bounded by foothill terrain to the north and east. Elevations in the vicinity of the corridor range from roughly 300 feet along the river bottom to over 1,000 feet on adjacent ridgelines in neighboring communities (Lakeside Fire Safe Council 2024; Eucalyptus Hills Fire Safe Council 2009).

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Slopes in these upland areas can exceed 50 degrees, creating steep gradients that can accelerate upslope fire runs under certain weather conditions.

Emergency Response
The Project Site is located within the SFD’s jurisdictional response area. SFD currently operates three fire stations, SFD Fire Station 4, which is located approximately 1 mile South of the Project Site at 8950 Cottonwood Avenue, and SFD Station 5, which is located approximately 0.06 miles north of the Project Site at 9130 Carlton Oaks Drive (City of Santee 2025a). In addition to the two permanent fire stations, the City opened an interim fire station, SFD Fire Station 20, in October 2025, which is located at the City Operation Yard at 9530 Via Zapador, approximately 1 mile south of the Project Site (City of Santee 2025a). Generally, each agency is responsible for structural fire protection and wildland fire protection within their area of responsibility. However, mutual aid agreements enable non-lead fire agencies to respond to fire emergencies outside their district boundaries. Mutual aid agreements in the City and City of San Diego include all emergency responses and rely on a closest unit concept. Fire agencies cooperate on a statewide master mutual aid agreement for wildland fires and there are mutual aid agreements in place with neighboring fire agencies and typically include interdependencies that exist among the region’s fire protection agencies for structural and medical responses. These agreements are voluntary, as no local governmental agency can exert authority over another.

4.6.2 Relevant Plans, Policies, and Ordinances
Federal
National Fire Protection Association Codes, Standards, Practices, and Guides National Fire Protection Association codes, standards, recommended practices, and guides are developed through a consensus standards development process approved by the American National Standards Institute. This process

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brings together professionals representing varied viewpoints and interests to achieve consensus on fire and other safety issues. National Fire Protection Association standards are recommended guidelines and nationally accepted good practices in fire protection but are not laws or codes unless adopted as such or referenced as such by the California Fire Code (CFC) or the local fire agency.

Federal Wildland Fire Management Policy
The Federal Wildland Fire Management Policy was developed in 1995, updated in 2001, and again in 2009 by the National Wildfire Coordinating Group, a federal multi-agency group that establishes consistent and coordinated fire management policy across multiple federal jurisdictions. An important component of the Federal Wildland Fire Management Policy is the acknowledgment of the essential role of fire in maintaining natural ecosystems. The Federal Wildland Fire Management Policy and its implementation are founded on the following guiding principles, found in the Guidance for Implementation of Federal Wildland Fire Management Policy (National Wildfire Coordinating Group 2009):
▪ Firefighter and public safety is the first priority in every fire management activity. ▪ The role of wildland fire as an essential ecological process and natural change agent will be incorporated into the planning process.
▪ Fire management plans, programs, and activities support land and resource management plans and their implementation.
▪ Sound risk management is a foundation for all fire management activities. ▪ Fire management programs and activities are economically viable, based upon values to be protected, costs, and land and resource management objectives.
▪ Fire management plans and activities are based upon the best available science. ▪ Fire management plans and activities incorporate public health and environmental quality considerations. ▪ Federal, state, tribal, local, interagency, and international coordination and cooperation are essential. ▪ Standardization of policies and procedures among federal agencies is an ongoing objective.

National Fire Plan
The National Fire Plan, officially titled Managing the Impacts of Wildfire on Communities and the Environment: A Report to the President In Response to the Wildfires of 2000, was a presidential directive in 2000 as a response to severe wildland fires that had burned throughout the United States. The National Fire Plan focuses on reducing fire impacts on rural communities and providing assurance for sufficient firefighting capacity in the future. The plan addresses five key points: firefighting, rehabilitation, hazardous fuels reduction, community assistance, and accountability. The plan provides technical, financial, and resource guidance and support for wildland fire management across the United States. The U.S. Department of Agriculture and the Department of the Interior are working to successfully implement the key points outlined in the plan (DOI and USDA 2000).

International Fire Code
Created by the International Code Council, the International Fire Code addresses a wide array of conditions hazardous to life and property, including fire, explosions, and hazardous materials handling or usage (although not a federal regulation, but rather the product of the International Code Council). The International Fire Code places an emphasis on prescriptive and performance-based approaches to fire prevention and fire protection systems.

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Updated every 3 years, the International Fire Code uses a hazards classification system to determine the appropriate measures to be incorporated to protect life and property (often times these measures include construction standards and specialized equipment). The International Fire Code uses a permit system (based on hazard classification) to ensure that required measures are instituted.

State
California Government Code
California Government Code Sections 51175 through 51189 provide guidance for classifying lands in California as fire hazard areas and requirements for management of property within those lands. CAL FIRE is responsible for classifying FHSZs based on statewide criteria and makes the information available for public review. Further, local agencies must designate, by ordinance, Very High FHSZs within their jurisdiction based on the recommendations of CAL FIRE.

Section 51182 sets forth requirements for maintaining property within fire hazard areas, such as defensible space, vegetative fuels management, and building materials and standards. Defensible space around structures in fire hazard areas must consist of 100 feet of fuel modification on each side of a structure, but not beyond the property line unless findings conclude that the clearing is necessary to significantly reduce the risk of structure ignition in the event of a wildfire. Clearance on adjacent property shall only be conducted following written consent by the adjacent owner. Further, trees must be trimmed from within 10 feet of the outlet of a chimney or stovepipe, vegetation near buildings must be maintained, and roofs of structures must be cleared of vegetative materials.

Exemptions may apply for buildings with an exterior constructed entirely of nonflammable materials.

California Code of Regulations
Title 14 Natural Resources
Title 14, Division 1.5, Chapter 7, Subchapter 3, Fire Hazard, also sets forth requirements for defensible space if the distances specified above cannot be met. For example, options that have similar practical effects include noncombustible block walls or fences, 5 feet of noncombustible material horizontally around the structure, installing hardscape landscaping or reducing exposed windows on the side of the structure with a less-than-30-foot setback, or additional structure hardening such as those required in the California Wildland–Urban Interface Code, California Code of Regulations Title 24, Part 7, Chapter 5.

Title 24 California Building Standards Code
California Fire Code
Part 9 of Title 24 contains the CFC, which incorporates by adoption the International Fire Code with necessary California amendments. The purpose of this code is to establish the minimum requirements to safeguard the public health, safety, and general welfare from the hazards of fire, explosion, or dangerous conditions in new and existing buildings, structures, and premises, and to provide safety and assistance to firefighters and emergency responders during emergency operations.

The CFC and Office of the State Fire Marshal provide regulations and guidance for local agencies in the development and enforcement of fire safety standards. The CFC is updated and published every 3 years by the California Building Standards Commission. The 2025 CFC took effect on January 1, 2026.

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California Wildland–Urban Interface Code
CRR Part 7 of Title 24 refers to the California Wildland–Urban Interface (WUI) Code. It establishes construction and site-development requirements for buildings located in fire-prone WUI areas, focusing on reducing structure ignitions during wildfires. It covers ignition-resistant building materials, exterior fire-resistant features such as roofing, siding, and glazing, vegetation management and defensible-space requirements, and standards for decks, vents, and accessory structures. The code also addresses fire-hazard severity classifications, access and water-supply criteria for firefighting, and design measures intended to limit ember intrusion, radiant-heat exposure, and direct flame contact. Together, these provisions support resilient development in communities facing increasing wildfire risk. The 2025 California Wildland–Urban Interface Code is a fully integrated code based on the 2024 IWUIC.

California Public Resources Code
California Public Resource Code, Section 4290, requires minimum fire safety standards related to defensible space that are applicable to residential, commercial, and industrial building construction in State Responsibility Area lands and Local Responsibility Area lands classified and designated as Very High FHSZs. These regulations include road standards for fire apparatus access, standards for signs identifying roads and buildings, fuel breaks and green belts, and minimum water supply requirements. It should be noted that these regulations do not supersede local regulations that equal or exceed minimum regulations required by the state.

California Public Resource Code, Section 4291, requires a reduction of fire hazards around buildings located adjacent to a mountainous area, forest-covered lands, brush-covered lands, grass-covered lands, or land that is covered in flammable material. It is required to maintain 100 feet of defensible space around all sides of a structure, but not beyond the property line unless required by state law, local ordinance, rule, or regulations. Further, California Public Resource Code, Section 4291, requires the removal of dead or dying vegetative materials from the roof of a structure, and trees and shrubs must be trimmed from within 10 feet of the outlet of a chimney or stovepipe. Exemptions may apply for buildings with an exterior constructed entirely of nonflammable materials.

Fire Hazard Severity Zones
CAL FIRE maps FHSZs based on fuel loading, slope, fire history, weather, and other relevant factors as directed by California Public Resources Code, Sections 4201–4204, and California Government Code, Sections 51175– 51189. FHSZs are ranked from Moderate to Very High and are categorized for fire protection within a Federal Responsibility Area, State Responsibility Area, or Local Responsibility Area under the jurisdiction of a federal agency, CAL FIRE, or local agency, respectively. As shown in Figure 3-4, Fire Hazard Severity Zones, portions of the Project Site are in areas designated as Moderate and High FHSZs, and bordered by areas designated as Moderate, High and Very High FHSZs to the north and south.

California Strategic Fire Plan
The 2024 Strategic Fire Plan for California reflects CAL FIRE’s focus on fire prevention and suppression activities to protect lives, property, and ecosystem services, and natural resource management to maintain the state’s forests as a resilient carbon sink to meet California’s climate change goals and to serve as important habitat for adaptation and mitigation. The Strategic Fire Plan for California provides a vision for a natural environment that is more fire resilient, buildings and infrastructure that are more fire resistant, and a society that is more aware of and responsive

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to the benefits and threats of wildland fire, all achieved through local, state, federal, tribal, and private partnerships (CAL FIRE 2024).

Mutual Aid Agreements
The California Disaster and Civil Defense Master Mutual Aid Agreement, as provided by the California Emergency Services Act, provides statewide mutual aid between and among local jurisdictions and the state. The statewide mutual aid system exists to ensure that adequate resources, facilities, and other supports are provided to jurisdictions whenever resources prove to be inadequate for a given situation. Each jurisdiction controls its own personnel and facilities but can give and receive help whenever needed.

Local
California Disaster and Civil Defense Master Mutual Aid Agreement As provided for in the California Emergency Services Act, this agreement was developed in 1950 and adopted by all 58 California counties. This statewide mutual aid system is designed to ensure that adequate resources, facilities, and other support are provided to jurisdictions whenever their own resources prove to be inadequate to cope with a given situation. San Diego County is located in Mutual Aid Region 6 of the state system, which also includes Imperial, Riverside, San Bernardino, Inyo, and Mono counties.

San Diego County Emergency Operations Plan
The San Diego County Emergency Operations Plan (EOP) is a comprehensive emergency management system that provides for a planned response to disaster situations associated with natural disasters, technological incidents and nuclear defense operations. The Plan includes operational concepts relating to various emergency situations, identifies components of the Emergency Management Organization and describes the overall responsibilities for protecting life and property and assuring the overall well-being of the population. The plan also identifies the source of outside support that might be provided (through mutual aid and specific statutory authorities) by other jurisdictions, state and federal agencies and the private sector (County of San Diego 2022).

San Diego County Multi-Jurisdictional Hazard Mitigation Plan The purpose of the County’s Multi-Jurisdictional Hazard Mitigation Plan (MJHMP) (County of San Diego 2023) is to identify the County’s hazards, review and assess past disaster occurrences, estimate the probability of future occurrences, and set goals to mitigate potential risks to reduce or eliminate long-term risk to people and property from natural and human-made hazards. An important San Diego County MJHMP component is the Community Emergency Response Team, which educates community members about disaster preparedness and trains them in basic response skills, including fire safety.

City of Santee Emergency Operations Plan
According to the City’s Safety and Environmental Justice Element, “The City’s Emergency Operations Plan (EOP) was prepared with input from partnering jurisdictions within San Diego County to provide a system for the effective management of emergencies consistent with the County EOP, and to ensure the protection of life, property, and the environment before, during, and after an emergency event, natural disaster, or technological incident” (City of Santee 2025b).

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Santee General Plan
Safety Element and Environmental Justice Element
The purpose of the Safety Element is to reduce loss of life, injuries, and damage to property resulting from natural and human-caused public safety hazards including flooding, geologic and seismic hazards, fire, traffic hazards and crime (City of Santee 2025b). The following goals and policies are applicable to wildfire:

Goal 1: Reduce impacts from and improve the City of Santee’s capacity to adapt to natural hazards Objective 3: Minimize injures, loss of life, and property damage resulting from fire hazards Policy 3.13 Mandate that public and private landowners for all existing land uses comply with all applicable state and local requirements and implement site-specific safety measures that mitigate to a low-risk condition around or near public facilities, infrastructure, and natural resources.

Policy 3.15 Require public and private landowners to minimize the risk of wildfire moving from wildland areas to developed properties or from property to property by increasing structural hardening measures (e.g., fire-rated roofing and fire-resistant construction materials and techniques), maintaining and improving defensible space on site, and supporting vegetation management in adjacent undeveloped areas
Policy 3.21 Support the continuation of long-term maintenance of fire hazard reduction projects, such as a weed abatement program (existing), community fire breaks, and private and public road clearance.

Objective 12: Increase resiliency to the impacts of wildfire.

Policy 12.1 Continue to require fire prevention planning and defensible space in all new development within Very High Fire Hazard Severity Zones or wildland–urban interface.

Santee City CouncilAugust 12, 2026

Santee City Council
August 12, 2026