City Council / Housing Authority
May 15, 2023

CEQA Initial Study
Pedley Spreading Grounds Pond Enhancements
February 2023
Prepared For:

City of Pomona
Water Resources Department
148 N. Huntington Street
Pomona, California 91768
Prepared By:

Stantec Consulting Services Inc.
300 North Lake Avenue, Suite 400
Pasadena, California 91101
Attachment No. 3

Pedley Spreading Grounds Pond Enhancements Page i
Initial Study February 2023
Table of Contents

Section Name Page Number
Section 1 Project and Agency Information .................................................................................. 1-1

1.1 Project Title and Lead Agency ....................................................................................... 1-1

1.2 Project Background and Objective ................................................................................. 1-1

1.2.1 Project Background ................................................................................................. 1-2

1.2.2 Project Objective ..................................................................................................... 1-4

1.3 Project Location and Environmental Setting .................................................................. 1-4

1.4 Project Description ......................................................................................................... 1-6

1.4.1 PSG Basins.............................................................................................................. 1-6

1.4.2 Stormwater Conveyance Improvements ................................................................. 1-7

1.4.3 Park and Educational Facilities ............................................................................... 1-9

1.4.4 Construction ............................................................................................................ 1-9

1.4.5 Operations and Maintenance ................................................................................. 1-12

1.5 Project Outreach ........................................................................................................... 1-14

1.6 Applicable Land Use Plan ............................................................................................ 1-14

1.7 Project Approvals ......................................................................................................... 1-15

Section 2 Environmental Analysis ............................................................................................... 2-1

2.1 Environmental Factors Potentially Affected .................................................................. 2-1

2.2 Agency Determination ................................................................................................... 2-1

2.3 Environmental Checklist ................................................................................................ 2-2

2.3.1 Aesthetics ................................................................................................................ 2-2

2.3.2 Agriculture and Forestry Resources ........................................................................ 2-5

2.3.3 Air Quality .............................................................................................................. 2-7

2.3.4 Biological Resources ............................................................................................ 2-14

2.3.5 Cultural Resources ................................................................................................ 2-26

2.3.6 Energy ................................................................................................................... 2-30

2.3.7 Geology and Soils ................................................................................................. 2-32

2.3.8 Greenhouse Gas Emissions ................................................................................... 2-37

2.3.9 Hazards and Hazardous Materials ........................................................................ 2-40

2.3.10 Hydrology and Water Quality ............................................................................... 2-45

2.3.11 Land Use and Planning ......................................................................................... 2-52

2.3.12 Mineral Resources ................................................................................................ 2-53

2.3.13 Noise ..................................................................................................................... 2-55

2.3.14 Population and Housing ........................................................................................ 2-60

2.3.15 Public Services ...................................................................................................... 2-61

2.3.16 Recreation ............................................................................................................. 2-62

2.3.17 Transportation ....................................................................................................... 2-63

2.3.18 Tribal Cultural Resources ..................................................................................... 2-67

2.3.18 Utilities and Service Systems................................................................................ 2-72

2.3.19 Wildfire ................................................................................................................. 2-74

2.3.20 Mandatory Findings of Significance ..................................................................... 2-76

Page ii Pedley Spreading Grounds Pond Enhancements
February 2023 Initial Study
Section 3 References, Abbreviations, and Report Preparation ................................................... 3-1

3.1 References and Bibliography ......................................................................................... 3-1

3.2 Acronyms and Abbreviations ......................................................................................... 3-6

3.3 Preparers of the Initial Study ........................................................................................ 3-10

List of Tables
Table No. Page No.

Table 1 Basin Grading ............................................................................................................ 1-7 Table 2 Typical Constr uction Equipment ............................................................................. 1-11 Table 3 Anticipated Pedley Spreading Gr ounds Operation and Maintenance ...................... 1-13 Table 4 Estimated Project C onstruction Emissions ................................................................ 2-9 Table 5 Estimated Project Operational Emissions ................................................................ 2-10 Table 6 Localized Significance of Construc tion and Estimated Operational Emissions (lbs/day) ............................................................................................................. 2-11 Table 7 Vegetation Co mmunities and Land Cover Types .................................................... 2-15 Table 8 Impacts to Vegetation Comm unities and Land Cover Types .................................. 2-17 Table 9 Sensitive Plant and Wildlife Species with Moderate Potential to Occur ................. 2-19 Table 10 Estimated Construction Greenhous e Gas Emissions (Unmitigated) ....................... 2-38 Table 11 Dry Systems Checklist of V ector Minimization Measures ...................................... 2-40 Table 12 Cortese List Databases and Results for City of Claremont ..................................... 2-43 Table 13 Summary of Anticipated C onstruction Stormwater BMPs ...................................... 2-47 Table 14 Annual Average Pollutant Load Reduction for Proposed Conditions ..................... 2-48 Table 15 Ambient Noise Levels near PSG, Claremont, California ........................................ 2-56 Table 16 Construction Equi pment Noise Levels .................................................................... 2-57

List of Figures
Figure No.

Figure 1 Pedley Spreading Grounds Existing Operations ........................................................ 1-3 Figure 2 Project Location .......................................................................................................... 1-5 Figure 3 Proposed Storm Drain System Improvements ........................................................... 1-8 Figure 4 Proposed Vault Structure in Mills Avenue ................................................................. 1-9 Figure 5 Photograph of Pedley Spreading Grounds ................................................................. 2-4 Figure 6 Vegetation Communities and Land Cover Types .................................................... 2-16 Figure 7 Vegetation Communities and Land Cover Types with Impacts ............................... 2-18

Appendices

A Air Quality Modeling Output
B Biological Resources Technical Report
C Paleontological Resource Assessment

February 2023 Initial Study

Section 1
Project and Agency Information

1.1 PROJECT TITLE AND LEAD AGENCY
Project Title: Pedley Spreading Grounds Pond Enhancements Project Lead Agency Name: City of Pomona, Water Resources Department Lead Agency Address: 148 N. Huntington Street
Pomona, California 91768
Contact Person: Jorge D. Anaya, Senior Water Resources Engineer Contact Phone Number: (909) 772-4240
Project Sponsor: Same as lead agency

1.2 PROJECT BACKGROUND AND OBJECTIVE
The City of Pomona Water Resources Departme nt is the lead agency under the California Environmental Quality Act (CEQA) and has prepared this Initial Study (IS) to address the impacts of implementing the Pedley Spreading Grounds ( PSG) Pond Enhancements (proposed project).

The PSG consists of three basins and is currently configured to receive flows from the adjacent (to the north) neighborhood through 42-inch and 18-inch storm drains, as well as process water from the adjacent Pedley Filtration Plant (PFP). Located in the City of Claremont, California, the PSG are owned and operated by the City of Pomona.

The proposed project is a colla borative effort between the Citie s of Pomona and Claremont to capture, treat, and infiltrate lo cal urban runoff into the existi ng PSG to increase water supply through stormwater recharge and to decrease non-point source po llutants. Funding to implement the project is being sought from the Safe Clean Water Program, which is funded by a parcel tax intended to increase Los Angeles County local water supply, improve water quality, and invest in making communities greener and more livable. The mission of the Pomona Water Resources Department is to protect and manage groundwater resources for the people of the City of Pomona and to provide the cleanest water possible to residents and businesses.

Design of the project is described in the Preliminary Design Report (PDR) (Pomona, 2022). The project includes: grading of the existing PSG basins to enhance percolation, modifications to an existing stormwater junction diversion structure, construction of a new control vault to improve stormwater conveyance to the basins, new water quality pretreatment structure, inlet storm drain extensions, energy dissipater and riprap pads, stilling basin and equalizer structures, spillways, access ramps and roadway improvements, and PFP outlet interconnect piping and controls.

Additionally, the project includes implementation of improvements (pathway, plantings, educational signage, viewing area with benches, fencing, and a bike rack) at the Chaparral Park north of the spreading grounds.

Section 1 - Project Description

February 2023 Initial Study
The decision-making body for consideration and adoption of the CEQA document for the project is the Pomona City Council - a mayor and six council members, each representing a geographic district.

1.2.1 Project Background

1.2.1.1 ESGVWMG
The Cities of Pomona, Claremont, San Dimas, and La Verne formed the East San Gabriel Valley Watershed Management Group (ESGVWMG), and are collectively subject to the National Pollutant Discharge Elimination System (NPD ES) Municipal Separate Storm Sewer System (MS4) Permit No. R4-2021-0105 (Permit). MS4 perm its authorize public entities to discharge pollutants from public stormwat er systems to waters of th e United States. The ESGVWMG updated their Watershed Management Plan (WMP) to comply with the MS4 Permit in May 2022.

The WMP identifies best management practices (BMP) to reduce or eliminate pollutants from entering the MS4 in compliance with the water qua lity-based effluent limits of the Permit. A Reconnaissance-Level Recharge St udy in the Six Basins recommend ed eight projects to help ESGVWMG comply with Permit requirements while enhancing groundwater recharge (Six Basins Watermaster, 2020). The proposed pr oject at PSG was identified to help achieve MS4 Permit compliance while enhancing st ormwater recharge to the unde rlying Six Basins groundwater basins.

1.2.1.2 Six Basins Watermaster
The Six Basins are a group of ad jacent groundwater basins, located just south of the San Gabriel Mountains in eastern Los Angeles and western San Bernardino Counties. Surface-water runoff and recharge at basins located along the foot of the San Gabriel Mountains provide the main source of groundwater replenishment to the Six Basins. Local water-supply agencies also recharge water imported from the Metropolitan Water District of Southern Califor nia (Metropolitan).

Groundwater is integral to the re gional water supply, with 70 pe rcent (as of 2019 ) of Pomona’s water produced from groundwater wells located throughout Pomona and Claremont.

A stipulated judgement adjudi cated pumping and storage rights for the Six Basins in 1998 (Southern California Water Company vs. City of La Verne, et al.). The Judgment prescribes the coordinated management of the Six Basins with the objective that the parties to the Judgment can reliably pump their respective rights and ma ximize the beneficial us e of groundwater. The Judgment also established the Si x Basins Watermaster - a committe e of representatives (City of Claremont, City of Pomona, Ci ty of Upland, Golden State Wa ter Company, Pomona College, Pomona Valley Protective Association, San Antonio Water Company, and Three Valleys Municipal Water District) charge d with implementing the physical solution called for in the Judgement.

1.2.1.3 Previous Environmental Documentation
The Six Basins Watermaster prepared the Six Basins Strategic Plan Draft Program EIR (PEIR) to evaluate the potential environmental effects of the implementation of a long-term regional plan to increase groundwater recharge, increase water storage and decrease the reliance on State supplied water within the Six Basins (TVMWD, 2021). The PEIR describes the environmental impact of Section 1 – Project Description
Pedley Spreading Grounds Pond Enhancements Page 1-3
Initial Study February 2023
projects proposed in the Six Basins Strategic Plan, one of which is enhancing stormwater recharge at the PSG. Based on the analysis present in the re port, the project will have no impact, less than significant impacts, or less than significant impacts as mitigated for aesthetics, air quality, biological resources, cultural resources, hazardous materials, transportation, geology and soils, hydrology and water quality, noise, and utility systems. Mitigation measures adopted as part of the PEIR that are relevant to the proposed PSG project are referenced in the Environmental Assessment (Section 2 of this In itial Study). Rewording of some of the measures has been conducted for clarity and applicability to the proposed PSG project.

1.2.1.4 Existing Operations
The PSG consists of three basins and is currently configured to receive flows from the adjacent neighborhood to the north through storm drains (the 42-inch on Radcliffe Drive, 30-inch on Mills Avenue and 18-inch on the western corner of the PSG), as well as process water from the adjacent Frank G. Pedley Memorial Filtration Plant (Figure 1). Originally constructed in 1962, the filtration plant is permitted to treat up to 4.0 million gallons per day (mgd) of raw surface water for delivery to the City of Pomona. The tr eatment processes include coagul ation, clarification, disinfection, and filtration. Two on-site reservoirs store trea ted water. Approximately 0.45 acre-feet per day (afd) flows from the filtration plant to the PSG from daily operations (supernatant, backwash carriage water, analyzer process water, and sludge from the gravity sludge thickener). This represents approximately 1.5 percent of the to tal storage capacity of PSG of 29.78 af. When discharges from the Canon Waterline to the filt ration plant exceed 4 mgd or have high turbidity, flows are diverted directly to PSG via the overflow structure and PFP bypass pipe. Per the Pomona 2019 Integrated Water Supply Plan Update, typically, 500 acre-feet per year (afy) are spread at the PSG. Design of the project is based on the a ssumption that 13.26 ac-ft per day (4.32 mgd) are needed to be allocated within the PSG for storage of the potential maximum volume bypassed by the filtration plant into the PSG. Percolation te sting performed as part of the geotechnical investigations determined an adjusted design percolation rate of 6.22 inches per hour (in/hr) for the PSG.

Figure 1. Pedley Spreading Grounds Existing Operations

Section 1 - Project Description

February 2023 Initial Study

1.2.2 Project Objective
The objective of the project is to capture, treat, and infiltrate local urba n runoff into the PSG to enhance groundwater recharge of the Six Basins groundwater basins and thereby increase local water supply. Groundwater would then be withdrawn via existing wells to augment potable water resources in the City of Pomona service area. C onsistent with the MS4 permit, the project would increase local groundwater supplies while decreasing pollutant loading to surface waters.

Project goals are:
 Decrease impact of non-point source pollutants discharged into local water bodies  Optimize stormwater management and conveyance
 Prepare for more extreme and frequent drought conditions by capturing and recharging groundwater
 Provide community education and awareness of groundwater resources

1.3 PROJECT LOCATION A ND ENVIRONMENTAL SETTING

The PSG are located at 1691 Longwood Avenue in Claremont, on the eastern edge of the Los Angeles County in the Pomona Vall ey at the foothills of the Sa n Gabriel Mountains (Figure 2).

The site is centrally located within the City of Claremont, north of Inters tate 10, north of State Route 66, and south of the Foothill Freeway (210 Fwy). The project site is in Sections 3 and 34; Township 1 South and Township 1 North; Range 8 West; San Bernardino Meridian; within the United States Geological Survey (USGS) On tario 7.5-minute topographic quadrangle. The latitude/longitude of the approximate center of PSG is 34.116°N/-117.710°W. Elevation at the site is approximately 1,400 feet above mean sea leve l. Average annual temperatures range from a minimum of 44°F to a high of 92°F. Annual precipitation is 16.7 inches.

The three stormwater spreading basins (total of approximately 4 ponde d acres) are bounded by single-family residences on Radcliffe Street to the north; Chaparral Elementary School and single- family residences on Longwood Av enue on the east; single family residences on Akron Place, Lowell Avenue and Longwood Avenue on the south; and open space managed by the California Botanic Garden on the west. Separated from the PSG by Amherst Avenue, th e 86-acre garden is the largest botanic garden dedicated to California native plants, with more than 22,000 California native plants.

The PSG overlie the Six Basins groundwater basins, which underlie a portion of the Eastern San Gabriel Valley in Los Angeles County, and the City of Upland, and the unincorporated community of San Antonio Heights in western San Bern ardino County. The basins are Canyon Basin, Upper Claremont Heights Basin, Lower Claremont Heights Basin, Pomona Basin, Live Oak Basin and Ganesha Basin. The Six Basins area is bounded by the San Gabriel Mountai ns to the north, the San Jose Hills to the south, the Main San Gabriel Basin to the west, and the Chino Basin to the east.

V:\1858\Active\184031542_PedleySpreadingGrounds\03_data\gis\BRTR_FIgure1_ProjectLocationMap_20220621.mxd Revised: 2022-07-05 By: Dalaw 2 184031542
City of Pomona
Pedley Spreading Grounds Pond Enhancements Project
Claremont
Los Angeles County, California
Prepared by DL on 2022-06-21
TR by SET on 2022-06-21
IR by JV on 2022-06-21
Project Location
Disclaimer: This document has been prepared based on information provided by others as cited in the Notes section. Stantec has not verified the accuracy and/or completeness of this information and shall not be responsible for any errors or omissions which may be incorporated herein as a result. Stantec assumes no responsibility for data supplied in electronic format, and the recipient accepts full responsibility for verifying the accuracy and completeness of the data.

Notes

1. Coordinate System: NAD 1983 StatePlane California V FIPS 0405 Feet

2. Data Sources: Stantec 2022.

3. Background: Sources: Esri, GEBCO, NOAA, National Geographic, Garmin, HERE, Geonames.org, and other contributors Sources: Esri, HERE, Garmin, USGS, Intermap, INCREMENT P, NRCan, Esri Japan, METI, Esri China (Hong Kong), Esri Korea, Esri (Thailand), NGCC, (c) OpenStreetMap contributors, and the GIS User Community
Esri, Garmin, GEBCO, NOAA NGDC, and other contributors
Figure No.

Title
Project Location
Client/Project
Project Location
(At original document size of 8.5x11)
1:24,000
0 1,000 2,000
Feet
Project
Location
Section 1 - Project Description

February 2023 Initial Study

1.4 PROJECT DESCRIPTION

The proposed project includes incr easing the capacity of the PSG basins, improvements to the existing 30-inch Mills Avenue storm drain, instal lation of a water quality pretreatment device, modifications to interconnect the PFP outlet piping, and new park and educational facilities at the adjacent Chaparral Park.

1.4.1 PSG Basins
Under the proposed project, the existing spreadi ng basins will be regraded to increase their capacity by 3.0 acre-feet and allow additional infiltration. Drivable berms would be re-established between the basins to allow easier access for maintenance. Flow control features will also be added between basins and to the PFP outlet piping system.

The proposed design retains the three-basin design with each basin being separated by a 20-foot- wide embankment with access road. Thirty-inch a nd 24-inch diameter culverts will serve as equalization conduits with slide gates allowing for additional control over water distribution.

Access ramps (16-ft) will be added to each basin to allow for periodic maintenance and debris removal. All of the basin re-grading will be done at a maximum slope of 3:1. Basin 1 will be kept at the same depth as the existing condition with a bottom elevation of 385 feet. Basin 2 will be lowered by approximately 3 feet to a bottom elevation of 1382 feet. Basin 3 will be lowered slightly from 1383 to 1382.5 feet. Basin bottoms will be sloped at S=0.5 percent toward the low point elevation corresponding to the equalizer structures. A berm will be added to the south side of Basin 3 to add additional freeboard with an emergency spillway. This overflow will be lined with a grouted riprap pad at the base to reduce scour in the event of activation. Basin 1 will be treated as a pre-sedimentation basin for the outflow from the PFP. Basin 2 will feature a large capacity water quality pretreatment device, inlet pipe extension with energy dissipater and stilling basin for debris and sediment captures. Table 1 summarizes grading proposed for the three basins. With implementation of the proposed project:

 The capacity of the three basins will be 32.46 ac-ft
 The infiltration rate will be 6.22 in/hr based on geotechnical investigations. Up to 35.33 ac-ft/day can be infiltrated into all three basins.
 Adequate capacity for the 10-year storm event will be provided, based on:
 3.26 ac-ft/day from the 18-inch and 42-inch storm drains  7.64 ac-ft/day from the 30-inch storm drain
 13.26 ac-ft/day from the filtration plant can be accommodated as an emergency overflow, if necessary

Section 1 – Project Description
Pedley Spreading Grounds Pond Enhancements Page 1-7
Initial Study February 2023
Table 1. Basin Grading
Basin Bottom Area of
Basin (ft2)
Average
Length (ft)
Average
Width (ft)
Approximate
Volume (ft3)
Pre-sedimentation Basin for
PFP (Basin 1) 12,520 200 63 138,770
Spreading Basin 2 45,470 310 145 538,920
Spreading Basin 3 58,380 345 170 750,970
TOTAL 116,370
(2.67 acres) 1,428,660
(32.80 ac-ft)
Improvement of the basins is estimated to result in approximately 17,460 cubic yards of cut and 14,860 cubic yards of fill material. Providing for 15 to 20 percent shrinkage, soils are anticipated to be approximately balanced on-site.

1.4.2 Stormwater Conveyance Improvements
To convey flows to the enhanced basins, the project includes improving the existing 30-inch storm drain as a low-flow diversion pi pe to deliver stormwater runoff from a 375-acre drainage area to the PSG (Figure 3). The 30-inch Mills Avenue storm drain terminates at a junction structure, which receives flow from two 51-inch storm drains owned by the City of Claremont. Site reconnaissance showed a slide gate and weir that connects this 30-inch line to the junction structure. The slide gate would be removed and concrete plug material at the upstream opening of the pipe would be removed. By removing these restrictions and re- operating the diversion, the PSG can increase spreading by 7.64 acre-feet during the 24-hour, 85th-percentile storm.

Additionally, a below-grade vault (4 ft X 4 ft 10 ft) would be added along the 30-inch storm drain between the junction structure and the 210-Highway overpass (Figure 4). The vault would include a transition pipe, manually operated slide gate to control and optimize diversion flow while significantly reducing the likelihood of an overflow event at the PSG. The existing 30-inch storm drain will be operated as a low-flow diversio n pipe and a bypass for st orm flows entering the junction structure from the 51-inch storm drain. Any flows not en tering the 30-inch storm drain will flow into the Los Angeles County Flood Control District ow ned 69-inch storm drain that discharges to Thompson Creek in the west. The transition pipe will help control the flows into the PSG from the 375-acre drainage area resulting from the baseline modification. The manually operated slide gate will be mounted at the upstream end of the vau lt so that the diversion can be completely closed without risk of overflow ont o Mills Avenue. Visual inspection of staff gauges inside the basins along with Smartflow Smart Cover flow meters and totalizers on basin inlet pipes will be used to monitor when the PSG is nearing or at full capacity and inform operators to close the diversion slide gate. The ga te is planned to be open for most of the year and closed intermittently during storms. Therefore, it is not anticipated that water will be stagnant in the 30- inch storm drain for an extended period of time. After installa tion, the area around the vault including sidewalk, turf, hedges, and irrigation will be restored to pre-construction condition.

Section 1 - Project Description

February 2023 Initial Study

Figure 3. Proposed Storm Drain System Improvements

Section 1 – Project Description
Pedley Spreading Grounds Pond Enhancements Page 1-9
Initial Study February 2023

Figure 4. Proposed Vault Structure in Mills Avenue

1.4.3 Park and Educational Facilities
The project also includes new park and educational amenities to be installed at Chaparral Park.

Located at 1899 North Mills Ave nue, northeast of the PSG, the park is next to Chaparral Elementary School and includes a soccer field an d a playground. Improvements to the park will be detailed during future design, but may incl ude porous pavement walkway, minor planting of shrubs or native garden, viewing area with be nches and educational signage about the PSG, wrought iron fencing, and a bike rack. Plans and specifications will be refined to reflect community input obtained during public outreach efforts.

1.4.4 Construction
Construction for the proposed project will include demolition activities; grading and berm improvements; storm drainpipe installation; cast-in-place concrete; placing riprap; PFP bypass and interconnect piping modifications; slide gate, gate valve, and check valve installations; reoperation of the junction structure in Mills Avenue at Baseline Road; and precast concrete vault installation in Mills Avenue.

Section 1 - Project Description

February 2023 Initial Study
Construction activities are summarized below:

Basin Enhancements
 During grading for the proposed basins, earthwork volumes will be as close to balanced as possible; import of soil is not anticipated.
 Basin grading will include a stilling basin, access ramps, spillways, and culverts between the basins to equalize storage.
 Construction activities for the basin enhancements include:
 Earthwork Excavation for basins, 17,460 cubic yards (CY)  Earthwork Fill for basins and on-site roadways, 14,860 CY  Install 18" high-density polyethylene (HDPE) Pipe and Bedding, 71 linear ft  Install 24" HDPE Pipe and Bedding, 300 linear ft
 Install 24" Inline Gate Valve H-30 by Waterman Industries (or approved equal), 4  Construct Concrete Double Pipe Wing Walls
 Furnish and Install Rip Rap Slope Armor and Aprons, 185 CY  Construct Concrete Emergency Spillway, 2,000 sq-ft
Storm Drain Improvements
 Construction activities for the storm drain improvements will include:
 Clear and Grub
 Remove Existing Concrete Outlet Structures (2EA)
 Remove Existing 30” Reinforced Concrete Pipe (RCP), 10 linear feet  Remove Existing 42” RCP, 20 linear feet
 Remove Existing Slide Gates (3EA)
 Remove Existing Concrete Plug
 Remove Existing Portland cement concrete (PCC) sidewalk  Remove Existing Chain Link Fence and Slide Gate
 Remove 18” PFP Bypass Pipe (160 linear feet)
 Remove 18” PFP Outlet Pipe (15 linear feet)
 Remove 14” PFP Overflow Pipe (30 linear feet)
 Construct 30" to 18" Transition Per SPPWC 340-2, 5 linear ft  Install 4'x4' Vault with grated cover
 Furnish and Install 18" Slide Gate with Unseated Design Head of 35.4' by Waterman (or approved equal)

 Surface preparation includes breaking and rem oving pavement with concrete saws and pavement breakers. Debris would be hauled to an appropriate construction/demolition and inert (CDI) landfill or crusher plant via dump trucks. An estimated 20 CY of asphalt debris would be hauled off-site. Assuming 10-cubic yard trucks, approximately two trucks would haul construction debris off-site.

Section 1 – Project Description
Pedley Spreading Grounds Pond Enhancements Page 1-11
Initial Study February 2023
Small scrapers, backhoes or track hoes would be used for excavation, with hand digging to locate buried utilities. Water trucks would be used during excavation to control fugitive dust. Suitable soils would be retained for backfill. For excavations 5 feet deep or deeper, the construction contractor would develop a s horing and bracing plan to provide worker protection against the hazard of caving ground during the excavation.

 Steel plates would be used to cover any open areas left at the end of each workday.

 Backfill materials would be cl ean, fine earth, rock, or sand, free from gra ss, roots, brush, or other vegetation. Backfilled earth would be compacted using a roller or hydraulic tamper prior to paving where applicable.

 Asphalt concrete pavement, at least 3 inches thick, would be placed over an aggregate base.

Curbs will be repaired or re placed as necessary. Final step s would include striping and street cleaning as necessary.

General Construction Notes
 Approximately 10 construction workers (laborer s, equipment operators and supervisors) would be onsite at any one time.

 The specific equipment to be used would be determined by the construction contractor; typical equipment for construction at the basins and for th e storm drain improvements are listed in Table 2.

Table 2. Typical Construction Equipment
Equipment Approximate Number During Project
Construction
Dump Truck 1-4 (per day)
Scrapers 1-4
Hydraulic Breaker 1
Concrete Saw 1
Backhoe or Track Hoe 1
Front End Loader 1
Concrete Mixer Truck 1
Asphalt Paver 1
Roller Compactor 1
Pickup Utility Truck 1-2
Water Truck 1
Street Sweeper 1
Tractor (delivery trucks) 1 (per day)
 Construction is estimated to occur over approximately 4 to 6 months.  To avoid having to divert stormwater flows, it is anticipated that construction would not occur during the wet season (October 1 to April 1).

Section 1 - Project Description

February 2023 Initial Study
 Consistent with the City of Claremont Municipal Code, grading operations would occur only between the hours of 7:00 am and 8:00 pm weekdays and Saturdays, excluding national holidays. No construction activities would be permitted outside of the hours or on Sundays and federal holidays, unless a temporary waiver has been granted by the City of Claremont chief building official.
 Construction staging for equipment and vehicles will be on-site at the PSG.  Wind erosion and sediment erosion controls will be implemented as appropriate throughout the construction period.
 Up to two to three materials deliveries (fill soils, crushed base, pipe, pipe appurtenances, concrete, riprap, shoring materials) would be expected per day. It is anticipated that materials would be sourced locally. Materials would be received and stored at PSG.  Prior to the start of construction, the construction contractor would install erosion control measures, such as stabilized entrances, silt fences, gravel bags, filter fabric, and/or hay bales along the peripheries of construction sites.
 Prior to the start of construction, a Construction Traffic Management Plan would be developed. The Plan will detail lane closures, placement of barricades and safety lights, positioning of flagpersons, and covering of open trenches during non-work periods with a metal plate. Emergency response providers (City of Claremont Fire and Police Departments) would be notified in advance of the construction schedule, location, and lane closures.

It is assumed that at any one time, the maximum length of the construction zone (and therefore any lane closures) would be approximately 60 to 100 feet in length. At this time, it is envisioned that roadways will remain accessible with at least one lane of traffic operational.
 A least 2 weeks prior to the start of construction, the City of Pomona would notify residents and schools adjacent to and within 500 feet of the construction zone of the construction schedule. A contact name and phone number would be provided, as well as a project website address for project update information.

1.4.5 Operations and Maintenance
Existing maintenance of the PSG includes annual grubbing of approximately 1 inch of soil in the basins to improve percolation, annual soil remo val, monthly tree trimming, and monthly access road clearing. Soil removal involves moving soil from the bottom of the basin to the top of the basin to help widen the access roads.

Anticipated operations and maintenance activities with implementation of the proposed project are summarized in Table 3. Typical construction equipment for vegetation and debris removal would include dozers, graders, backhoes, loaders, and sc rapers. After removal of vegetation and debris and sediments, basin floors woul d be ripped using a bulldozer with ripper attachment, then smoothed by dragging a bar or sc reen behind the bulldozer. Sed iment removal would serve to Section 1 – Project Description
Pedley Spreading Grounds Pond Enhancements Page 1-13
Initial Study February 2023
maintain percolation rates at the basins, bu t would not substantially alter overall capacity.

Sediments may be stockpiled on-site for later use in the repair of eroded areas or side slopes, or hauled off-site. Side slopes may also be maintained through the addition of rip-rap or gabions, as necessary. Additional equipment for vegetation management may include tractor mowers, power trimmers, and manual tools such as pruning loppers, saws and clippers to trim and thin vegetation.

Debris removed using the vacuum truck from th e water quality pretre atment device, sump locations, equalizer structures, and PFP outlet interconnect piping c ontrol vault, and vegetation removed from the basins, would be disposed off-site at a landfill.

Table 3. Anticipated Pedley Spreading Grounds Operation and Maintenance Location Activity Schedule Description
Baseline Road
Junction Structure
Remove
debris
Annually Removing sediment and debris build up in the
junction structure using a vacuum truck
Vault on Mills
Avenue
Inspect
slide gate
Semi-
Annually
Inspecting condition of slide gate
Operate
slide gate
As Needed Opening and closing slide gate. Slide gate should close when PSGs are at or near capacity.

Lubricate
fittings
Annually Cleaning and lubricating fittings grease
Clean and
grease
operating
stems
Semi-
Annually
Cleaning and lubricating operating stems with valve
stem grease
Remove
Debris
Semi-
Annually
Removing sediment and debris build up from vault
using a vacuum truck
Basin Equalization
Piping
Operate
slide gates
As Needed Opening and closing slide gates to equalize water levels in the PSG. Slide gates should be open
unless isolation for maintenance of a particular
basin is required.

Remove
debris
As needed Removing sediment and debris from pipe openings PFP Discharge
Interconnect Piping

Inspect
Slide gates
Semi-
Annually
Inspecting condition of slide gates at interconnect
structure
Operate
slide gates
As Needed Opening and closing slide gates. One of two slide gates should be open at all times.

Operate
gate valves
As Needed Opening and closing gate valves to manage various discharge flow and desired outfall location
Remove
debris
As Needed Remove sediment and debris from interconnect
structure
Basins at PSG

Grubbing Annual,
after wet
season
Disturbing 1 inch of soil in the basins to improve
percolation
Soil
Removal
Annual Moving sediment build up at the bottom of the
basins to other onsite locations
Section 1 - Project Description

February 2023 Initial Study
Location Activity Schedule Description
Tree
Trimming
Monthly Trimming trees around the perimeter of the basins Road
Clearing
Monthly Clearing access roads
Chapparal Park To be maintained by City of Claremont

1.5 Project Outreach
During final design, additional outreach will be conducted per the Interested Parties Outreach/Engagement Plan (Appendix A of the PDR) . There will be an invitation of community members to key venues, such as the PFP, to explain water management goals and design a project that reconciles community and water management interests. The California Botanic Gardens, Chaparral Elementary School and Sustainable Claremont are project stakeholders. Materials such as briefing sheets with renderings of the completed project site will be provided in English and Spanish to gather feedback and/or comments ab out how the project is impacting the community.

Outreach will also be conducted at Chaparral Elem entary School to provide an overview of the project and educate students and staff on stormwater management.

1.6 APPLICABLE LAND USE PLAN
The PSG are designated as Public land use on the Land Use Plan of the City of Claremont’s General Plan (2014a), with a zoning of Park/ Resource Conservation (P/RC) (Claremont, 2014b).

The Public designation provides for a wide range of public uses, including public schools, transportation-related facilities, government uses , public utilities, libraries, museums, cultural facilities, and public service facilities. The P/RC category establishes and protects public properties for such purposes as preservation of natural resources, managed production of resources, outdoor recreation, and public health and safety. The P/RC District is intended to assure open space areas for uses such as public parks, outdoor recreation, cemetery uses, protection of natural habitat, preservation of cultural reso urces, management of groundwater resources, protection and conservation of mineral resources, and the protection of the public health and safety due to hazardous or special conditi ons. As noted below, water rech arge facilities, settling basins, and drainage channels are allowed uses.

The following uses and development are permitted in the P/RC District:

A. Parks and outdoor recreation facilities such as playgrounds, playing fields, and trails, open to the public and for which no admission fee is charged.

B. Community, senior and youth activity centers.

C. Cemetery uses.

D. Highway and freeway landscaping.

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Pedley Spreading Grounds Pond Enhancements Page 1-15
Initial Study February 2023
E. Water recharge facilities, settling basins, and drainage channels.

F. Natural habitat protection.

G. Preservation of architectural, historic, cultural, and natural resources.

H. The growing of plants provided no sales occur at the site.

I. Facilities for use by the public such as benches, picnic tables, shade structures, paved walkways, parking lots, fencing, restroom buildings, other minor buildings, and ancillary improvements such as lighting related to permitted uses.

J. Commercial antenna/wireless telecommunication facilities pursuant to Chapter 16.100.

1.7 PROJECT APPROVALS
Permits, approvals, and notifications for projec t construction and operati on are anticipated to include:

Agency Potential Permit or Approval
State Water Resources Control
Board (SWRCB)
NPDES Construction Stormwater General Permit 2009-0009-DWQ Regional Water Quality Control
Board (RWQCB), Los Angeles
Region
Construction dewatering Waste Discharge Requirements (WDRs), if relevant. Note that based on the geotechnical report for the project (Converse, 2022), the groundwater table is not expected to be encountered during project construction.

California Department of
Transportation (Caltrans)
Transportation Permit - Transportation of heavy construction equipment and/or materials, which requires the use of oversized- transport vehicles on State highways
South Coast Air Quality
Management District (SCAQMD)
Dust Control Plan - Rule 403 requires the implementation of best available dust control measures (BACM) during active operations capable of generating fugitive dust. This rule also requires activities defined as “large operations” to notify the SCAQMD by submitting specific forms. A large operation is defined as any active operation on property containing 50 or more acres of disturbed surface area; or any earth moving operation with a daily earth-moving or throughput volume of 3,850 cubic meters (5,000 cubic yards), three times during the most recent 365 day period.

Permit to Construct/Permit to Operate – temporary operation of IC en
gines for power generation during construction, if relevant City of Claremont Building Permit - construction or operation of new slide gate, new pipeline development
City of Claremont Grading Permit - grading for basin enhancement City of Claremont Encroachment Permit - work at the intersection of Baseline Road and Mills Avenue; proposed Chaparral Park improvements
Section 1 - Project Description

February 2023 Initial Study
Agency Potential Permit or Approval
Owner of APN 8671-050-056
(Potential) Temporary Construction Easement, Permanent
Easement - Depending on the location of the property boundary in relation to the vault improvements, these easements may be necessary to encroach on the parcel.

Claremont Police and Fire
Departments, adjacent
homeowners, schools and
businesses
Notification of project construction schedule and lane closures, as relevant

February 2023 Initial Study
Section 2
Environmental Analysis

2.1 ENVIRONMENTAL FACTOR S POTENTIALLY AFFECTED
The environmental factors checked below could potentially be significantly affected by this project, but mitigation has been identified to reduce impacts to less than significant levels.

Aesthetics Greenhouse Gas Emissions Public Services
Agriculture and Forestry
Resources Hazards and Hazardous Materials Recreation
Air Quality Hydrology and Water Quality Transportation
Biological Resources Land Use and Planning Tribal Cultural Resources Cultural Resources Mineral Resources Utilities and Service Systems Energy Noise Wildfire
Geology and Soils Population and Housing Mandatory Findings of Significance

2.2 AGENCY DETERMINATION
On the basis of this initial evaluation:

I find that the project COULD NOT have a significant effect on the environment, and a NEGATIVE DECLARATION will be prepared.

I find that although the project could have a significant effect on the environment, there will not be a significant effect in this case because revisions in the project have been made by or agreed to by the City of Pomona. A MITIGATED NEGATIVE DECLARATION will be prepared.

I find that the project MAY have a significant effect on the environment, and an ENVIRONMENTAL IMPACT REPORT is required.

I find that the project MAY have a “pot entially significant impact” or “potentially significant unless mitigated” impact on the environment, but at least one effect 1) has been adequately analyzed in an earlier document pursuant to applicable legal standards, and 2) has been addressed by mitigation measures based on the earlier analysis as described on attached sheets. An ENVI RONMENTAL IMPACT REPORT is required, but it must analyze only the effects that remain to be addressed.

I find that although the project could have a signific ant effect on the environment, because all potentially significant effects (a) have been analyzed adequately in an earlier EIR or NEGATIVE DECLARATION pursuant to applicable standards, and (b) have been avoided or mi tigated pursuant to that earlier EIR or NEGATIVE DECLARATION, including revisions or mitigation measures that are imposed upon the project, nothing further is required.

Signature:_____________________________________ Title: ________________________________________ Printed Name: _________________________________ Date:________________________________________ ect:
rect:
r
ect:

Senior Water Resources Engineer
Jorge D. Anaya
X
Section 2 – Environmental Analysis

February 2023 Initial Study

2.3 ENVIRONMENTAL CHECKLIST

2.3.1 Aesthetics
Issues and Supporting Information Sources
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporated
Less Than
Significant
Impact
No
Impact
Except as provided in Public Resources Code Section 21099, would the project:

a) Have a substantial adverse effect on a scenic vista? b) Substantially damage sceni c resources, including, but not limited to, trees, rock outcroppings, and historic
buildings within a state scenic highway?

c) Substantially degrade the existing visual character or quality of public views of the site and its surroundings? (Public views are those that are experienced from
publicly accessible vantage point). If the project is in an urbanized area, would the project conflict with applicable zoning and other regulations governing scenic quality?

d) Create a new source of subs tantial light or glare which would adversely affect day or nighttime views in the
area?

Discussion: Integral to the community’s image, the Claremont hillsides, including the Wilderness Park, establish a visual backdrop for the city . The City’s General Plan (2009) defines the Neighborhood Vision: The City will continue to imp lement the Hillside Or dinance as it pertains to this area.

Regarding visual resources, the City of Claremont General Plan (2009) includes the following policy:

Policy 2-1.4. Avoid development of isolated residential areas in the hillsides or other areas where such development would require significant infrastructure invest ment, adversely impact biotic resources, and/or create adverse visual impact.

a) and c) Less than Significant Impact . Existing views of the PSG are of three basins, and the adjacent PFP (Figure 5). Views of the existing junction structure and proposed vault structure are of paved roadways with adjacent residences.

Visual Impacts During Construction . Construction activities would include grading, excavation for the vault structure and construction of the storm drain improvements. Views of the project site during construction would include up to approximately 10 workers and approximately 10 vehicles/equi pment – such as loaders, scrapers, hydraulic breakers, backhoes, asphalt pavers and dump trucks. The impact would be limited to approximately 4 to 6 months. Construction-related impacts on visual character of the site would be temporary and less than significant.

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Pedley Spreading Grounds Pond Enhancements Page 2-3
Initial Study February 2023
Visual Impacts During Operation . Once the storm drain improvements are installed, the road surfaces will be restored and the aesthetic s of the sites would be similar to existing conditions. At the PSG the existing trees and shrubs along the northern portion of the property will be kept in place to screen the site from adjacent residents. Basin maintenance activities would be confined to the PSG property, occur infrequently, and use equipment such as tractors, backhoes, and dump trucks, the same as under existing conditions. Since the project would not block views of the mountains, in clude tall structures or propose building materials that cause glare, the project would not conflict with any of the City’s policies related to the protection of scenic resources. Improvements at Chaparral Pa rk may include plantings , a beneficial visual impact. Overall, operational impacts on the visual character of the project sites would be less than significant.

Mitigation Measure

Impacts from project constructi on and operation of the proposed project would be less than significant for visual resources. However, consistent with the Six Basins PEIR, mitigation measure AES-1 shall be implemented to further reduce project-related aesthetic impacts.

AES-1 Design Standards. Proposed facilities, including walls, gates, treatment facilities, etc., shall be designed in accordance with local desi gn standards in order to be complementary to the local area. Landscaping shall be installed and maintained in conformance with local landscaping design guidelines as appropriate to screen views of new facilities from surrounding areas to the extent feasible taking into consideration the needs of the project and except where such compliance is not required by California law.

b) No Impact . Scenic roadways are designated by Caltrans and the Federal Highway Administration. The closest Officially Designated Scenic Highway is Route 2 in Los Angeles, approximately 20 miles north of the PSG. The clos est eligible scenic highways are Route 57 through the Puente Hills and Route 142 in Chino Hills (both approximately 10 miles south of the PSG) (Caltrans, 2018). The stated intent of the California Scenic Highway program is to protect and enhance California's natural beauty and to protect the social and economic values provided by the State's scenic resources (Str eets and Highway Code Section 260). Observers along these roadways would not have views of the PSG or the construction activity for the storm drain improvements. Therefore, there would be no impacts from project construction or operation on views from a State scenic highway.
d) No Impact. The use of temporary lighting for basin and storm drain improvements would not be anticipated since construction activity would be conducted during the day. Existing security lighting present at PSG would not be altered by the project. Since the proposed project does not include new sources of light, there would be no impacts on light or glare.

Section 2 – Environmental Analysis

February 2023 Initial Study

Figure 5. Photograph of Pedley Spreading Grounds

Source: Stantec, July 2022

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Pedley Spreading Grounds Pond Enhancements Page 2-5
Initial Study February 2023

2.3.2 Agriculture and Forestry Resources
Issues and Supporting Information Sources
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporated
Less Than
Significant
Impact
No
Impact
Would the project:
a) Convert Prime Farmland, Unique Farmland, or Farmland of Statewide Importance (Farmland), as shown on the
maps prepared pursuant to the Farmland Mapping and
Monitoring Program of the California Resources Agency,
to non-agricultural use?

b) Conflict with existing zoning for agricultural use, or a Williamson Act contract?

c) Conflict with existing zoning for, or cause rezoning of, forest land (as defined in Public Resources Code section 12220(g)), timberland (as defined by Public Resources
Code section 4526), or timberland zoned Timberland
Production (as defined by Government Code section
51104(g))?

d) Result in the loss of forest land or conversion of forest land to non-forest use?

e) Involve other changes in t he existing environment which, due to their location or nature, could result in conversion of Farmland, to non-agricultural use or conversion of
forest land to non-forest use?

Discussion: Regarding the zoning for agricultural us e or impacts on sites under Williamson Act contracts, a review of city zoning maps for the cities of Claremont, La Verne, Pomona and Upland revealed that there are no project sites identified in the Strategic Plan that are zoned for agricultural uses or under Williamson Act contract. Therefore, implementation of the Strategic Plan and related projects would not result in any conflict with zoning for agricultural use or impact any sites under contract.
a) No Impact. The Farmland Mapping and Monitori ng Program (FMMP) does map Prime Farmland, Farmland of Statewide Importanc e, Unique Farmland, Farmland of Local Importance and Grazing Land in the project vicinity (California Department of Conservation, 2022). There is no important farmland mapped on the project sites nor is any farming conducted on or immediately adjacent to the project facilities. Therefore, the proposed project would have no impact on conversion of FMMP designated Farmland.

b) No Impact. The project sites are not zoned or mapped by the City of Claremont for agricultural use. The PSG are designated as Public land use in the City of Claremont’s General Plan, with a zoning of P/RC (Claremont, 2009). The Public designation provides fo r a wide range of public uses, including public schools, transportation-related facilities, government uses, public utilities, libraries, museums, cultural facilities, and public service facilities. The P/RC category establishes and protects public properties for such purposes as preservation of natural resources, managed production of resources, outdoor recreation, and public health and safety.

The P/RC District is intended to assure open space areas for uses such as public parks, outdoor recreation, cemetery uses, protect ion of natural habitat, preser vation of cultural resources, Section 2 – Environmental Analysis

February 2023 Initial Study
management of groundwater resources, protection and conservation of mineral resources, and the protection of the public he alth and safety due to hazar dous or special conditions. The junction structure and proposed vault are within city streets, adjacent to residentially-zoned areas.

Enacted in 1965, the California Land Conserva tion Act (Williamson Act) involves voluntary contracts between landowners and a city or county in which they agree to retain their lands in agriculture or other op en space uses for a minimum of 10 years. The landowners receive property tax relief on the lands under contract. No Williamson Act contracts are relevant for the project areas; therefore, the proposed project would have no impact on agricultural zoning or Williamson Act contracts.

c) and d) No Impact. Public Resources Code Section 12220 (g) defines "Forest land" as land that can support 10-percent native tr ee cover of any species, incl uding hardwoods, under natural conditions, and that allows for management of one or more forest resources, including timber, aesthetics, fish and wildlife, biodiversity, water quality, recreation, and other public benefits.

There are no timber production zones in the pr oject areas. The project areas are not used for timber harvest and the proposed basin and storm drain improvements would not alter existing use of the sites. Since the project would not re sult in conversion of fo rest land to non-forest use, the project would have no impact on forest lands.

e) No Impact. The project would not require construction on or adjacent to forest harvest areas or farmlands, or change the use of the projec t sites. Therefore, there would be no impact on agricultural operations from construction and operation of the proposed project.

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Pedley Spreading Grounds Pond Enhancements Page 2-7
Initial Study February 2023

2.3.3 Air Quality
Issues and Supporting Information Sources
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporated
Less Than
Significant
Impact
No
Impact
Would the project:
a) Conflict with or obstruct im plementation of the applicable air quality plan?

b) Result in a cumulatively considerable net increase of any criteria pollutant for which the project region is non- attainment under an applicable federal or state ambient air quality standard?

c) Expose sensitive receptor s to substantial pollutant concentrations?

d) Result in other emissions (such as those leading to
odors) adversely affecting a substantial number of
people?

Discussion:

The project site is located within the 6,745 s quare-mile South Coast Air Basin (SCAB), which includes all of Orange County a nd the non-desert portions of Lo s Angeles, Riverside, and San Bernardino County. SCAB is under the jurisdiction of the SCAQMD. The air quality within SCAB is primarily influenced by mete orology and a wide range of emi ssions sources, such as dense population centers, heavy vehicular traffic, and industry.

Criteria air pollutants are defined as pollutants for which the federal and state governments have established ambient air quality standards for outdoor concentr ations. The federal and state standards have been set at leve ls above which concentrations c ould be harmful to human health and welfare. These standards are designed to protect the most sensitive persons such as children, pregnant women, and the elderly, from illness or discomfort. Criteria air pollutants include ozone (O
3), nitrogen dioxide (NO2), carbon monoxide (CO), sulfur dioxide (SO2), particulate matter 2.5 microns or less in diameter (PM 2.5), particulate matter 10 microns or less in diameter (PM10), and lead (Pb). Pursuant to the federal Clean Air Act, the SCAQMD is responsible for reducing emissions of criteria air pollutants for which SCAB is considered in non-attainment. The SCAB region is designated as nonattainment for O3 and PM2.5 under the California and National Ambient Air Quality Standards (AAQS) and PM10 under the California AAQS (SCAQMD, 2018).

SCAQMD’s 2016 Air Quality Management Plan (2016 AQMP) is the regional blueprint for achieving air quality standards a nd healthful air. The 2016 AQMP c ontains a comprehensive list of pollution control strategies directed at reducing emissions and achieving AAQS in coordination with the California Air Resources Board (CARB) , U.S. Environmental Pr otection Agency (U.S.

EPA), and the Southern California Associ ation of Governments (SCAG) 2016 Regional Transportation Plan/Sustainable Communities Strategy (RTP/SCS). SCAQMD is currently preparing the Revised 2022 AQMP, which has not yet been approved at the time this analysis was prepared (SCAQMD, 2022).

Section 2 – Environmental Analysis

February 2023 Initial Study
a) Less than Significant Impact. The following addresses the project’s consistency with SCAQMD’s 2016 AQMP. In accordance with the procedures established in SCAQMD’s CEQA Air Quality Handbook, the following criteria ar e required to be addressed in order to determine the project’s consistency with applicable SCAQMD policies:
 Criterion 1. Whether a project would result in an increase in the frequency or severity of existing air quality violations or cause or contribute to new violations or delay timely attainment of air quality standards or the interim emission reductions specified in the AQMP.

As discussed below under Impact AQ-b and Impact AQ-c, the proposed project would fall below SCAQMD project-level and localized thresholds. Moreover, the proposed project would not introduce any new stationary sources or expose sensitive receptors to substantial pollutant concentrations. Therefore, the project would not increase the frequency or severity of an existing violation or cause or contribute to new violations for these pollutants and would also not delay timely attainment or air quality standards or interim emission reductions specified in the AQMP.
 Criterion 2. Whether a project would exceed the assumptions in the AQMP based on the year of project buildout and phase.

With respect to the second criterion for determining consistency with AQMP growth assumptions, the projections in the AQMP for achieving air quality goals are based on the assumptions within SCAG’s 2016 RTP/SCS regarding population, housing, and growth trends. The proposed project would increase the capacity of existing recharge basins and improve an existing storm drain. The project would not result in any new population, housing, or long-term employment opportunities in the region. As a result, the project is consistent with the growth projections in the AQMP.

The determination of AQMP consistency is primarily concerned with the long-term influence of a project on air quality in SCAB. The proposed project woul d not result in a long-term impact on the region’s ability to meet State and federal air quality standards. Therefore, the project is consistent with the applicable ai r quality plan and impac ts would be less than significant.
b) Less than Significant Impact. In developing thresholds of significance for air pollutants, the SCAQMD considered the emission levels for which a project’s individual emissions would be cumulatively considerable. If a project exceed s the identified significance thresholds, its emissions would be cumulativel y considerable, resulting in significant advers e air quality impacts to the region’s existing air quality conditions. Construction and operational emissions were estimated in the California Emissions Estimator Model (CalEEMod).

Construction Emissions - Emis sions from construction-related activities are generally short- term but may still cause advers e air quality impacts. The proj ect would generate emissions from construction equipment exhaust, worker travel, and fugitive dust. These construction emissions include criteria air pollutants from the operation of heavy construction equipment.

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Pedley Spreading Grounds Pond Enhancements Page 2-9
Initial Study February 2023
Grading of the site would require in 17,460 CY of soil excavation and 14,860 CY of fill. With provisions for 15 to 20 pe rcent shrinkage, this results in an approximately balanced site. In addition, the project would import approximately 185 CY of rip rap slope armor. Grading estimates account for excavation of the basins and excavation for storm drain upgrades.

The construction schedule used in the analysis represents a “worst-case” analysis scenario since emission factors for construction equipment decrease as the analysis year increases due to improvements in technology and more stringe nt regulatory requir ements. Therefore, construction emissions would decrease if the construction schedule were delayed to later years.

The duration of construction act ivity and associated equipment represents a reasonable approximation of the expected construction fleet as required pursuant to CEQA Guidelines 15064(f)(5).

As shown in Table 4, the project constr uction emissions would be below the SCAQMD significance thresholds, and therefore, impacts would be less than significant and are not considered cumulatively considerable. Note that during constructi on, per guidance from the City of Pomona Land Development General No tes, and the requirements of SCAQMD Rule 403, dust would be controlled by watering.

Table 4. Estimated Project Construction Emissions
Construction
Year
Emissions (lbs/day)
VOC NOx SOx CO PM10 PM2.5
2023 3.39 34.75 0.06 28.74 21.12 11.32
SCAQMD
Thresholds
75 100 150 550 150 55
Exceed? No No No No No No
Note: Construction emission estimates do not account for fugitive dust controls required under SCAQMD Rule 403.

Source: CalEEMod output files (Appendix A)

Operational Emissions - Operational emissions would be generated from periodic maintenance activities which include annual grubbing, annua l soil removal, monthly tree trimming, and monthly access road clearing. Soil removal involves moving soil from the bottom of the basin to the top of the basin to help widen the acc ess roads. Grubbing involves disturbing 1 inch of soil in the basins to improve percolation.

Soil removal and grubbing were assumed to requ ire excavators, graders, rubber tired dozers, scrapers, and loaders based on CalEEMod defaults for grading construction. Soil removal and grubbing were assumed to occur over a 2 week period. Soil removal and grubbing were modeled as construction inputs within the CalEEMod model.

Tree trimming was assumed to re quire an aerial lif t, chainsaws, and woodchipper and was assumed to occur 12 days per year (once per month). Road clearing was assumed to require a street sweeping truck and was assumed to occur 12 days per year (once per month). Both tree trimming and road clearing would be conducted by two workers. Other maintenance activities include occasional inspection and cleaning of pipeline vaults. In spection and cleaning of the Section 2 – Environmental Analysis

February 2023 Initial Study
pipeline would occur annually or semi-annually and may require a vacuum truck to remove sediment and debris build up. Similar to tree trimming and road clearing activities, it was conservatively assumed other maintenance activities would be performed by two workers. Tree trimming, road clearing, and other maintenance activities were modeled within the CalEEMod model as operational inputs. Employee trips for tree trimming, road clearing, and other maintenance activities were calculated off-model using the California Air Resources Board’s EMFAC2021 emission factors. It was assumed that a maximum of 12 employee trips would occur in any single day. Employee trips for th e soil removal and grubbing were calculated within the model.

As shown in Table 5, the pr oject operational emissions would be below the SCAQMD significance thresholds, and therefore, impacts would be less than significant and are not cumulatively considerable. Table 5 below also presents a conservative estimate of operational emissions as the table assumes all operational activities would occur at once. In reality, this is unlikely, and in practice emissions would be lower.

Table 5. Estimated Project Operational Emissions
Activity
Emissions (lbs/day)
VOC NOx SOx CO PM10 PM2.5
Soil Removal
and Grubbing

3.39 34.56 0.06 28.75 10.85 5.02
Tree trimming,
road clearing,
and other
maintenance
activities

1.79 11.83 0.03 13.96 0.55 0.52
Area 0.38 <0.01 0.00 <0.01 <0.01 <0.01
Mobile 0.09 0.02 0.002 0.34 0.005 0.002
Total 5.65 46.41 0.10 43.05 11.41 5.54
SCAQMD
Thresholds
55 55 150 550 150 55
Exceed? No No No No No No
Note: Soil removal and grubbing emission estimates do not account for fugitive dust controls required under SCAQMD Rule 403.

Source: CalEEMod output files (Appendix A)

c) Less than Significant Impact. Project emissions were reviewed that could expose sensitive receptors to pollutant concentrations to a de gree that would significantly affect sensitive receptors (residences, schools, childcare centers, playgrounds, retirement homes, convalescent homes, hospitals, and medical cl inics). This section addresse s the exposure of sensitive receptors of localized significance thresholds (LST), construction-generated fugitive dust (PM10), construction and opera tional-generated diesel part iculate matter (DPM), or operational CO hotspots.

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Initial Study February 2023

Localized Significance Thresholds Analysis

Construction. The maximum on-site daily emissions for NOx, CO, PM10, and PM2.5 were calculated using CalEEMod and compared to the applicable SCAQMD LSTs. The site lies within site receptor area (SRA) 10 based on a 5-acre site with receptors approximately 25 meters from the site. The project site size is based on the approximate acres that would be graded per day (see Appendix A for calculat ions). Additionally, localized construction emissions include compliance with SCAQMD Ru le 403 which is required to reduce impacts related to fugitive dust from the project site.

Table 6 below conservatively shows both on-site and off-site emissions and demonstrates that construction emissions would be below the SCAQMD LSTs, and therefore, impacts would be less than significant.

Table 6. Localized Significance of Construction and Estimated Operational Emissions (lbs/day)
Year NOx CO PM10 PM2.5
Construction
2023 On-site Maximum Emissions 34.79 28.74 10.3 5.77
SCAQMD Construction Thresholds 236 1,566 12 7
Exceed? No No No No
Source: CalEEMod Output (Appendix A)

Operation - Project operation would result in periodic maintenance activities. SCAQMD Rule 403 would be applicable to all operations that may generate f ugitive dust and, therefore, fugitive dust reduction measures including watering exposed areas and reducing vehicle speeds on unpaved roads would be implem ented during operational activit ies. Operational activities would occur throughout the site and would not be concentrated in any one area throughout the day. Therefore, receptors near the site would not be constantly exposed throughout the day.

Finally, operational maintenance activities would likely not occur at once and would be spread throughout the year. As such, operational ac tivities would not exceed SCAQMD LST thresholds and would be less than significant.

Fugitive Dust Emissions - Fugitive dust (PM10) would be generated from site grading and other earth-moving activities. Most of this fugitive dust would remain localized and would be deposited near the project site. However, the po tential for impacts from fugitive dust exists unless control measures are im plemented to reduce the emissions from the project site. The project would be required to comply with SCAQMD Rules a nd Regulations, including Rule 403 that requires the implementation of best management practices to reduce fugitive dust emissions. The impact from fugitive dust emissions would be less than significant.

Toxic Air Contaminants (TAC) Construction - The greatest potential for TAC emissions during construction would be from DPM emis sions associated with heavy equipment Section 2 – Environmental Analysis

February 2023 Initial Study
operations. According to SCAMQD methodology, health effects from carcinogenic air toxics are usually described in terms of individual cancer risk. An individual cancer risk is the likelihood that a person continuously exposed to concentrations of TACs over a 70-year lifetime will contract cancer. Gi ven the short-term constructi on schedule, the project would not result in a long-term (i.e., 70-year) source of TAC emissions. Therefore, the impact from construction TAC emissions would be less than significant.

Toxic Air Contaminants – Operation
DPM. The SCAQMD recommends that health risk assessme nt (HRAs) be conducted for substantial individual sources of DPM. These land uses include truck stops and warehouse distribution facilities that generate more than 100 trucks per day or more than 40 trucks with operating transport refrigeration units (SCAQMD, 2022). The project would not include these types of land uses and is not considered to be a substantial source of DPM emissions. The project would include the use of on-site, off-road equipment that would emit DPM emissions during operation. However, the use of this equipment would be periodic and would not be concentrated in one area throughout the day. As such, given the short-term and episodic nature of operational maintenance, th e project would not generate significant levels of DPM emissions.

TACs. Typical sources of acu tely and chronically hazardous TACs including industrial manufacturing processes which include chrome plating, electrical manufacturing, or petroleum refining. The project would not include these types of poten tial industrial manufacturing process sources. As such, the project would not release substantial amounts of TACs.

Carbon Monoxide Hotspots. An analysis of CO “hot spots” determines whether the change in the level of service of an intersection caused by a proposed project would have the potential to result in exceedances of CAAQS or NAAQS. Vehicular exceedances occur primarily when vehicles are idling at intersections. With the turnover of older vehicles, CO concentrations have steadily declined throughout the state. SCAB was re-designated as attainment in 2007 and CO is no longer addressed in the SCAQMD’s AQMP.

During operation, vehicle trips would occur from maintenance workers to the site. Operational maintenance would be periodic . The site would not attract any other vehicle trips from customers, vendors, or residents. Therefore, the project does not trigger the need for a detailed CO hotspots model.

Conclusion
The proposed project would not result in a h ealth risk impact fro m TACs and would not generate a CO hotspot. Moreover, constructio n and operation of the proposed project would fall below SCAQMD LSTs. Therefore, impacts would be less than significant. d) Less than Significant Impact. Construction - Diesel exhaust and volatile organic compounds (VOCs) would be emitted during construction of the project from equipment exhaust, painting, and paving activities, which are objectionable to some; however, construction activities would be minimal and emissions would disperse rapidly from the project site and therefore would not Section 2 – Environmental Analysis
Pedley Spreading Grounds Pond Enhancements Page 2-13
Initial Study February 2023
create objectionable odors affecting a substantial number of people. As such, construction odor would be less than significant.

Operation - Land uses typically associated with odors include wastewater treatment facilities, waste-disposal facilities, or agricultural opera tions. The project does not contain land uses typically associated with emitting objectionable odors and, as such, this impact would be less than significant.

Section 2 – Environmental Analysis

February 2023 Initial Study

2.3.4 Biological Resources
Issues and Supporting Information Sources
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporated
Less Than
Significant
Impact
No
Impact
Would the project:
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, and 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 wit h 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 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 provisi ons of an adopted Habitat
Conservation Plan, Natural Community Conservation
Plan, or other approved local, regional, or state habitat conservation plan?

Discussion: A biological resources reconnaissance-leve l survey of the project site and an additional 300-ft buffer zone was conducted on May 2, 2022, by Stantec Consulting Services Inc. (Stantec). The approximately 87-acre area is defined as the Biological Study Area (BSA). Details of the survey methods, backgr ound data, and existing conditions are included in the Biological Resources Technical Report (BRTR, Appendix B).

Existing Biological Setting

Three plant communities defined by Sawyer et al. (2009) and U.S. National Vegetation Classification (USNVC) (2022), one vegetation community descriptive in nature, and seven land cover types were mapped in the BSA and are summarized in Table 7 and depicted in Figure 6.

Section 2 – Environmental Analysis
Pedley Spreading Grounds Pond Enhancements Page 2-15
Initial Study February 2023
Table 7. Vegetation Communities and Land Cover Types in the BSA Vegetation Communities and Land Cover Types Area of BSA (acres) Vegetation Communities
Common deerweed (Acmispon glaber, formerly Lotus scoparius) shrubland

3.08 Mulefat (Baccharis salicifolia) thickets 0.98
Eucalyptus spp. Ruderal Forest Alliance – Eucalyptus woodland 1.04 Olea spp. Semi-Natural Stand – Olive woodland 3.09
Subtotal 8.19
Land Cover Types
Disturbed/Developed 68.33
Disturbed/Developed 0.03
--Concrete Lined Channel 6.42
Residential Landscaping 1.21
Infiltration Ponds 1.91
Vegetated Channel 0.02
Ruderal herbaceous 0.80
Subtotal 78.72
Total 86.91
Source: Sawyer et. al 2009

The aquatic features on the project site consist of artificial wetlands and non-wetlands within the existing basins and channels. Isolated and restrict ed to the project site, the aquatic features are exempt from SWRCB jurisdiction b ecause the features are for dete ntion, retention, infiltration, and treatment of stormwater runoff and other po llutants or runoff subject to regulation under a municipal stormwater permitting program (SWRCB, 2021).

A total of 94 common native and no n-native plants species were observed in the BSA. A total of 19 common wildlife species were observed in th e BSA - 18 bird species and 1 mammal. No reptiles, amphibians, or fish were observed in the BSA. A full list of the common plant and wildlife species observed are included in Appendix B.

Based on California Department of Fish and Wildlife (CDFW) California Natural Diversity Data Base (2022a), USFWS Information for Planning and Consultation (2022b), and the Strategic Plan PEIR, 38 sensitive species and 52 sensitive wildlife species occur within the region defined as 10 miles of the BSA. Most of the sensitive plant and animal species known to occur in the region have been determined to have no or a low potenti al to occur on the project site. A table of the 90 sensitive/special-status plant and wildlife specie s and their potential to occur in the BSA are included in Appendix B.

No critical habitat occurs in the BSA (USFWS, 2022a), and no sensitive pl ant or animal species were observed within the BSA during surveys on May 2, 2022 (Appendix B).

Avila Way
Akron Pl
Hobart Dr
Shaw Pl
Menlo Dr
Trinidad Cir
Kenyon Pl
Academy Ct
Benedict Ave
Austin Ct
Loyola Ct
Brescia
Ave
Cape Cod Ct
Brockport Ct
Barrington Ct Frostburg Cir
Judson Ct
LowellAv
e
Salisbury Ln
Allegany Ct
Middlebury Ct
Glassboro
Ave
Warner St
CapuchinWay
New
Haven
Ave
Aquinas
Ave
Claremont Heights Dr
Edinboro
Ave
Greensboro
Ct
Chaparral Dr
Lander Cir
Andover Dr
Abilene
W
ay
Longwood Ave
Aurora Dr
Clarion Pl
Blue Mountain Way
Black Hills Dr
Scottsbluff Dr
DenverAve
Rockford Dr
Amherst St
N
M
ills
Ave
N
M
ills
Ave
E Radcliffe DrRadcliffe Dr
E Baseline Rd
210
210
V:\1858\Active\184031542_PedleySpreadingGrounds\03_data\gis\BRTR_FIgure2_VegetationMap_20220621.mxd Revised: 2022-07-05 By: Dalaw 6 184031542
City of Pomona
Pedley Spreading Grounds Pond Enhancements Project
CEQA Initial Study
Claremont
Los Angeles County, California
Prepared by DL on 2022-06-21
TR by SET on 2022-06-21
IR by JV on 2022-06-21
Vegetation Communities and Land
Cover Types
Disclaimer: This document has been prepared based on information provided by others as cited in the Notes section. Stantec has not verified the accuracy and/or completeness of this information and shall not be responsible for any errors or omissions which may be incorporated herein as a result. Stantec assumes no responsibility for data supplied in electronic format, and the recipient accepts full responsibility for verifying the accuracy and completeness of the data.

Notes

1. Coordinate System: NAD 1983 StatePlane California V FIPS 0405 Feet

2. Data Sources: Stantec 2022. Township/Section/ Range Data from BLM 2018. Quadrangle data from USGS 2017.

3. Background: Source: Esri, Maxar, Earthstar Geographics, and the GIS User Community Figure No.

Title
Project Location
Client/Project
Biological Survey Area
Project Footprint
Vegetation Communities and Land Cover Types
Mulefat thickets
California Botanic Garden
Concrete Lined Channel
Disturbed/Developed
Common deerweed shrubland
Eucalyptus woodland
Olive woodland
Residential Landscaping
Retention Pond
Ruderal herbaceous
Vegetated Channel
(At original document size of 8.5x11)
1:6,000
0 250 500
Feet
Section 2 – Environmental Analysis
Pedley Spreading Grounds Pond Enhancements Page 2-17
Initial Study February 2023

a) Less than Significant Impact with Mitigation Incorporated. The project site includes habitats such as common deerweed ( Acmispon glaber formerly Lotus scoparius) shrubland, mulefat ( Baccharis salicifolia ) thickets, Eucalyptus spp. woodland, infiltration ponds, and vegetated channel areas that could provide habitat for sensitive species (Sawyer et al., 2009).

The 300-foot survey buffer consists mostly of disturbed/developed ar eas and the California Botanic Garden just west of the project site (Figure 7). Ba sed on the design of the proposed project, Table 8 presents the impact acreages to vegetation communities and land cover types on the project site.

Table 8. Impacts to Vegetation Communities and Land Cover Types Vegetation Communities and Land Cover Types Permanent Impacts Acres
Vegetation Communities
Deerweed scrubland 1.24
Mulefat (Baccharis salicifolia) thickets 0.66
Eucalyptus woodland 0.97
Olive woodland 0.12
Subtotal 2.99
Land Cover Types
Disturbed/Developed 2.90
Infiltration Ponds 1.91
Vegetated Channel 0.02
Ruderal herbaceous 0.80
Subtotal 5.63
Total 8.62
Source: Sawyer et al., 2009

The following subsections describe potential impacts to sensitive species.

Sensitive Plant Species

During the May 2, 2022 site survey, no sensitive pl ants were observed at the project site and no sensitive plants species that are known to occur in the region have a high potential to occur on the site. There is a moderate potential for five sensitive plant species to occur on the project site (Table 9). Nevin’s barberry (Berberis nevinii), a perennial shrub, ha d moderate potential to occur, but would have been observed during the survey if it was present.

Avila Way
Akron Pl
Hobart Dr
Shaw Pl
Menlo Dr
Trinidad Cir
Kenyon Pl
Academy Ct
Benedict Ave
Austin Ct
Loyola Ct
Brescia
Ave
Cape Cod Ct
Brockport Ct
Barrington Ct Frostburg Cir
Judson Ct
LowellAv
e
Salisbury Ln
Allegany Ct
Middlebury Ct
Glassboro
Ave
Warner St
CapuchinWay
New
Haven
Ave
Aquinas
Ave
Claremont Heights Dr
Edinboro
Ave
Greensboro
Ct
Chaparral Dr
Lander Cir
Andover Dr
Abilene
W
ay
Longwood Ave
Aurora Dr
Clarion Pl
Blue Mountain Way
Black Hills Dr
Scottsbluff Dr
DenverAve
Rockford Dr
Amherst St
N
M
ills
Ave
N
M
ills
Ave
E Radcliffe DrRadcliffe Dr
E Baseline Rd
210
210
V:\1858\Active\184031542_PedleySpreadingGrounds\03_data\gis\CEQA_Figure6_VegetationMap_with_Impacts_20230214.mxd Revised: 2023-02-14 By: kdelapena 7 184031542
City of Pomona
Pedley Spreading Grounds Pond Enhancement Project
CEQA Initial Study
Claremont
Los Angeles County, California
Prepared by KDLP on 2022-12-19
TR by SET on 2022-12-19
IR by MT on 2022-12-19
Vegetation Communities and Land
Cover Types with Impacts
Disclaimer: This document has been prepared based on information provided by others as cited in the Notes section. Stantec has not verified the accuracy and/or completeness of this information and shall not be responsible for any errors or omissions which may be incorporated herein as a result. Stantec assumes no responsibility for data supplied in electronic format, and the recipient accepts full responsibility for verifying the accuracy and completeness of the data.

Notes

1. Coordinate System: NAD 1983 StatePlane California V FIPS 0405 Feet

2. Data Sources: Stantec 2022. Township/Section/ Range Data from BLM 2018. Quadrangle data from USGS 2017.

3. Background: Source: Esri, Maxar, Earthstar Geographics, and the GIS User Community Figure No.

Title
Project Location
Client/Project
Biological Survey Area
Project Footprint
Project Impacts (9.49 acres)
Vegetation Communities and Land Cover Types
Mulefat Thickets
California Botanic Garden
Concrete Lined Channel
Disturbed/Developed
Common Deerweed Shrubland
Eucalyptus woodland
Olive Woodland
Residential Landscaping
Retention Pond
Ruderal Herbaceous
Vegetated Channel
(At original document size of 8.5x11)
1:6,000
0 250 500
Feet
Section 2 – Environmental Analysis
Pedley Spreading Grounds Pond Enhancements Page 2-19
Initial Study February 2023
Table 9. Sensitive Plant Species with Moderate Potential to Occur Scientific Name Co mmon Name Status
(federal/state)
Suitable habitat
Plant Species
Berberis nevinii Nevin's barberry FE/SE, 1B.1 deerweed shrubland, mulefat thickets
Calochortus weedii var. intermedius intermediate mariposa-lily -/1B.2 deerweed shrubland Calystegia felix lucky morning glory -/1B.1 infiltration pond Pseudognaphalium leucocephalum white rabbit-tobacco -/2B.2 deerweed shrubland, mulefat thickets
Sagittaria sanfordii Sanford's arrowhead -/1B.2 infiltration pond Sources: CDFW 2022a, 2022b, 2022c, 2022d; CNPS 2022, USFWS 2022b Notes: Federal Designation California Rare Plant Rank (CRPR) FE = Federally Endangered 1B Plants rare, thr eatened, or endangered in California and elsewhere 2B Plants rare, threatened, or endangered in California and common State Ranking elsewhere
SE = State Endangered .1 Seriously threaten ed in California (high degree/immediacy of threat) .2 Fairly threatened in Calif ornia (moderate degree/immediacy of threat)

Prior to the start of construction Mitigation Measure BR-1, a preconstruction survey, will be implemented and focus on the following four species:
 intermediate mariposa-lily (Calochortus weedii var. intermedius)  lucky morning glory (Calystegia felix),
 white rabbit tobacco (Pseudognaphalium leucocephalum)  Sanford’s arrowhead (Sagittaria sanfordii)

If no sensitive plant species are found, then construction and operation of the proposed project would not be expected to result in direct or indirect impacts to sensitive plant species. If a sensitive plant species is found and cannot be avoided, a relocatio n strategy would be developed and coordination with CDFW and/or USFWS would be conducted as described in mitigation measure BR-1.

Sensitive Bird Species

During the May 2, 2022, survey, 18 common bird species were observed in the project site and surrounding area. If construction for the proposed project occurs during the avian nesting season (generally extends from February 1 th rough August 31, but it can vary slightly from year to year based on seasonal weather conditions and some raptors species may nest as early as January), impacts to nesting birds could occur. The Migratory Bird Treaty Act (MBTA) of 1918 (16 U.S.C. 703-711) does not allow for take of migratory birds. The MBTA makes it unlawful to possess, buy, sell, purchase, barter or “take” any migratory bird listed in Title 50 of the Code of Federal Regulations Part 10. “Take” is defined as possession or destruction of migratory birds, their nests, or eggs. Disturbances that cause nest abandonment and/or loss of reproductive effort or the loss of habitats upon which these birds depend may be a violation of the MBTA. The MBTA prohibits killing, possessi ng, or trading in migratory birds except in Section 2 – Environmental Analysis

February 2023 Initial Study
accordance with regulations prescribed by th e Secretary. The MBTA encompasses whole birds, parts of birds, and bird nests and eggs.

If implementation of the proposed project were to impact nesting birds protected under the MBTA, the impacts would be considered sign ificant. Therefore, Mitigation Measure BR-2 would require preconstruction nest surveys prior to ground disturbance, nesting bird surveys, and avoidance measures for ac tive nests. With implementati on of mitigation measure BR-2, impacts on nesting birds would be less than significant.

Sensitive Fish/Invertebrate Species

One sensitive species, Crotch’s bumblebee (Bombus crotchii), has a high potential to occur on the proposed project site. Crotch bumblebee may occur on flowers in the proposed project site.

This bumblebee is most likely to occur in the deerweed shrublands. If a Crotch’s bumblebee occurs on site, it can fly away during cons truction. No significant impacts to Crotch’s bumblebee are expected.

Sensitive Reptile Species

During surveys conducted within the project site, no common or sensitive reptiles were observed. All but one of sensitiv e reptiles known to occur in th e region were determined to have a low or no potential to occur in the project site; one species, southern California legless lizard (legless lizard) ( Anniella stebbinsi), a CDFW Species of Special Concern (SSC), was determined to have a moderate potential to occur.

Construction activities associated with the proposed project coul d result in the direct loss of legless lizard should it occur. Di rect impacts could result from potential mechanical crushing during construction, trampling of friable soils required for burrowing, removal of brush piles, fugitive dust, and general disturbance due to increased human activity. Project implementation may also result in permanent loss of mule fat thickets. Indirect impacts could include compaction of soils and the introduction of non-native plant species.

In compliance with mitigation measure BR-1, preconstruction clearance surveys will be implemented. However, legless lizard may not be detected during preconstruction surveys since they would primarily occur in undergrou nd burrows. Therefore, if a legless lizard is detected during construction, construction will ha lt and a qualified biologist will relocate the lizard.

Sensitive Mammal Species

During surveys conducted within the proposed project area, no sensitive mammals were observed. All but one of the sensitive reptiles known to occur in the region were determined to have a low or no poten tial to occur in the pr oject site; one specie s, San Diego woodrat (Neotoma lepida intermedia), SSC, was determined to have a moderate potential to occur. If a San Diego woodrat nest was present during the survey on May 2, 2022, it would have been observed. During preconstruction surveys, the site will be surveyed again for San Diego Section 2 – Environmental Analysis
Pedley Spreading Grounds Pond Enhancements Page 2-21
Initial Study February 2023
woodrat nests. If an individual woodrat occurs on site, away from its nest, it could move away from construction. Although unlikely, if a nest is found, it will be marked and avoided to minimize impacts on San Diego woodrat.

Conclusion

Implementation of BR-1 and BR-2, specificall y preconstruction surveys, avoidance and minimization measures, and bi ological monitoring, would min imize impacts to sensitive species. In addition, mitigation measure BR-3, an environmental awareness and compliance training program will be presented to all construction personnel.

With implementation of mitigation measures BR-1 through BR-3, impacts on sensitive species would be reduced to less than significant levels.

Mitigation Measures

The following mitigation measures would reduce project-relate d impacts on biological resources to less than significant levels.

BR-1 Plant and Wildlife Preconstruction Clearance Surveys and Biological Monitoring.

Prior to ground disturbance or vegetation clearing within the proposed project site, a qualified biologist shall conduct preconstruction plant surveys and wildlife clearance surveys (no more than 7 days prior to site disturbing activities ) where suitable habitat is present and will be directly impacted by construction activities.

If a rare plant species is found, it will be fenced and avoided. If it cannot be avoided, then an appropriate relocation strategy shall be deve loped and coordinated with CDFW and/or USFWS. Common wildlife found within the project site or in areas potentially affected by the proposed project shall be relocated to the nearest suitable habitat that would not be affected by the proposed project prior to the start of construction.

Any sensitive wildlife species found within a proposed projec t impact area shall be relocated by a qualified biologist to suitable habitat outside the impact area prior to the start of ground- disturbing activities.

A qualified biologist shall be on site during initial ground disturbance activities (minimally for the first week of construction). Thereafter, monitoring shall be conducted at a minimum of once per week throughout the construction phase. The qualified biologist(s) shall have the right to halt all activities that are in violation of sensitive species protection measures. Work shall proceed only after sensitive species are relocated or allowed to leave the site, and the species is no longer at risk.

If a sensitive wildlife species is relocated by the qualified biologist during preconstruction clearance surveys or monitoring, records of all detection, capture, and release of sensitive species shall be reported to CDFW.

Section 2 – Environmental Analysis

February 2023 Initial Study
BR-2 Nesting Bird Surveys and Avoidance Measures. If initial site disturbance is scheduled to begin during the avian nesting season (Feb ruary 1 through August 31; January 1 through August 31 for raptors), breeding and nesting bird surveys shall be conducted by a qualified biologist no more than 3 days pr ior to the start of site distur bance. If constr uction activities carry over into a second nesting season(s), th e surveys shall be completed annually until the proposed project is complete. Surveys shall be conducted within 500 feet of all proposed project activities.

The City of Pomona shall coordinate with U SFWS if a federally endangered or threatened species is observed. The City of Pomona shall coordinate with CDFW if a State- endangered or threatened species is observed. If a CDFW species of special concern is observed nesting, it shall be reported to CDFW.

If breeding birds with active nests are found pr ior to or during construction, a qualified biological monitor shall establish a 300-foot buffer around th e nest, and no activities shall be allowed within the buffer(s) until the young have fledged from the nest or the nest fails; initial buffers for nesting raptors shall be 500 feet. The prescribed buffers for common species may be adjusted by the qualified biologist based on existing conditions around the nest, planned construction activities, tolerance of the species , and other pertinent fa ctors; for example, buffers for common passerines, often found to be habituated to human activity, may be adjusted down to 25 - 50 feet depending on the disturbance tolerance of each specific species.

Buffer adjustments for listed and/or other sensitive species shall be done in coordination with the USFWS and CDFW, as applicable. The qualified biologist shall conduct weekly monitoring of the nest to determine success or failure and to ensure that proposed project activities are not conducted within the buffer(s) until the nesting cycle is complete or the nest fails.

BR-3 Environmental Awareness Training. Prior to initial ground disturbance, all project personnel shall attend an environmental awar eness and compliance training program. The training program shall present applicable envi ronmental regulations and permit conditions.

The training program shall include applicable measures established for the proposed project to minimize impacts to avoid sensitive resources, habitats, and species. Subsequent training events shall be scheduled to support the training of new pe rsonnel. Dated sign-in sheets for attendees at these meetings shall be maintained and submitted to the City of Pomona.

b) and c) Less than Significant Impact with Mitigation Incorporated. Sensitive natural communities are defined by CDFW as “...communities that are of limited distribution statewide or within a county or region and are often vulnerable to environmental effects of projects.” All vegetation within the state is ranked with an “S” rank; however, only those that are of special concern (S1-S3 rank) are generally eval uated under CEQA (CDFW, 2022e). No CDFW sensitive natural communities occur in the proposed project site. Table 8 summarizes project impacts by vegetation and land cover types.

Substantial impacts to riparian habitat are co nsidered significant. Riparian areas generally occur on the bank of waterbody, of ten a stream or river, and ar e a transitional zone between Section 2 – Environmental Analysis
Pedley Spreading Grounds Pond Enhancements Page 2-23
Initial Study February 2023
terrestrial and aquatic habitat. Implementation of the proposed project would result in 0.66 acres of permanent impacts to riparian habitat (mulefat thickets).

Implementation of mitigation measure BR-4, which includes min imizing vegetation removal and compensation for impacts to riparian vegetation, would reduce impacts to sensitive riparian (i.e., mulefat thickets) habitats to a less than significant level.

Mitigation Measure

The following mitigation measure would reduce project-related impacts on riparian vegetation to less than significant levels.

BR-4 Riparian Vegetation Removal and Replacement. Construction activities shall be done in such a manner as to minimize the removal of native riparian vege tation (i.e., mulefat thickets). If impacts to native riparian vegetation removal cannot be avoided, the compensation for the permanent loss of habitats may be ach ieved either by a) on-si te habitat creation or enhancement of impacted communities with similar species compositions to those present prior to construction, b) off-site creation or enhancement of the impacted community type (or similar communities), or c) participation in an established mitigation bank program. Permanent impacts to native communities shall be restored/ mitigated at a minimum of a 2:1 ratio for on or off-site habitat restoration/ creation or participation in an established mitigation banking program.

Prior to the start of any project related activiti es (including removal of native vegetation), if on- or off-site mitigation is required, an eco system-based Habitat Mitigation and Monitoring Plan shall be prepared by persons with expertise in southern California ecosystems and native plant restoration techniques that will guide all restoration and monitoring activities. This plan shall include, at a minimum, the following:
 Provide the total acreage of unique sensitive vegetation communities impacted, and abundance, density, and cover of each plant species and vegetation layer impacted (i.e., ground cover, forbs, subshrub, shrub, and trees).
 Provide the specific location of on- and/or off-site mitigation area(s) and a science based factual discussion as to why the mitigation area(s) is appropriate for mitigating project- related impacts. Describe the environmental features (i.e., soils, slope, existing vegetation, hydrology) that would suggest the mitigation area(s) can support the vegetation and wildlife impacted by project activities.  Provide a vegetation survey conducted at a reference site containing the vegetation communities being mitigated, with as good or better-quality habitat, to document the density, abundance, diversity, and percent cover for each species by vegetation layer.  A schematic depicting the mitigation area.
 Proposed species list for creation/enhancement. A plant palette shall consist of species that are diverse with respect to growing duration (annual, perennial), life form (grasses, shrubs, trees, vines), and structure (ground cover, shrubs, tree canopy) that form the vegetation alliance that is being mitigated.
 Planting/seeding methodology (e.g., sources of local propagules, container sizes, and seeding rates).

Section 2 – Environmental Analysis

February 2023 Initial Study
 Planting schedule.
 Irrigation plan.
 Weeding schedule; and invasive plant control methods that reduce or eliminate the use of chemicals.
 Success criteria.
 Monitoring methodology and schedule extended across a sufficient time frame to ensure that the new habitat is established, self-sustaining, and capable of surviving drought.  Reporting requirements.

d) Less than Significant Impact. Wildlife movement corridors are defined on both a regional and on a local scale. Regionally, the project site does not fall within a movement corridor. On a local basis, the undeveloped areas on the project site provide low to moderate quality habitat for wildlife; but the surrounding area is dominated by development that impedes movement of reptiles, amphibians, and mammals.

Migratory birds may use the project site and vicinity for breeding, nesting, and foraging, or as transient rest sites during migration flights. B ecause the project is small, mostly within disturbed and developed areas, and of a short construction duration, impacts to the movement of any native resident or migratory fish or w ildlife species, to wildlife corridors, or to native wildlife nursery sites would be temporary, minor, and less than significant. Therefore, no mitigation measures are required.

e) Less than Significant Impact with Mitigation Incorporated. The project site is located within the City of Cl aremont. However, as the City of Pomona is the project proponent, relevant City of Pomona General Plan C onservation Component goa ls and policies were reviewed:

 Policy 7E.P11 Prior to development of area s with drainage features such as ponds, detention basins, or wetlands, a site-specific investigation shall be conducted to define the extent of drainage features, determine wetland permit requirements, and propose measures to mitigate any impacts on the resources.

 Policy 7E.P12 Conduct presence/absence biological surveys for sensitive plant and animal species during the appropriate time of year an d time of day in natural areas prior to any construction activities proposed adjacent to or within natural areas. If no special-status species [sensitive] are detected during these su rveys, then construction-related activities may proceed. If listed special st atus species are found within the construction zone, then avoid these species and their habitat or consult with USFWS and/or California Department of Fish and Game [Wildlife] prior to the commencement of construction.

 Policy 7E.P13 Conduct nesting bird surveys prior to any construction activities, including projects proposed to remove/disturb native and ornamental landscaping and other nesting habitat for native birds during bird breedi ng season from March 1 through August 31 (as early January 1 for some raptor s). If no nesting birds are de tected during these surveys, then construction-related activities may proceed. Active nests within and adjacent to the construction zone should be avoided and pr ovided a minimum buffer as determined by a Section 2 – Environmental Analysis
Pedley Spreading Grounds Pond Enhancements Page 2-25
Initial Study February 2023
biological monitor (CDFW recomm ends a 300-foot nest avoida nce buffer or 500 feet for all active raptor nests) or consult with the USFWS and/or CDFW prior to the commencement of construction.

In compliance with Policy 7E.P11 and Policy 7E.P12, a habitat assessment was conducted on May 2, 2022, and a BRTR was prepared. As desc ribed above, no sensitive species were observed on the project site. However, mi tigation measures BR-1 through BR-4 will be implemented to minimize impacts to sensitive speci es if any are identifi ed prior to or during construction. Consistent with Policy 7E.P13, mitigation measure BR-2 will be implemented if the proposed project occurs during the bi rd breeding season. With implementation of mitigation measures, impacts on bi ological resources policies woul d be reduced to less than significant levels.

f) No Impact. The project site is not within a Ha bitat Conservation Plan, Natural Community Conservation Plan, or other approved local, regional, or state habitat conservation plan.

Therefore, no impacts to a habitat plan would occur.

Section 2 – Environmental Analysis

February 2023 Initial Study

2.3.5 Cultural Resources
Issues and Supporting Information Sources
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporated
Less Than
Significant
Impact
No
Impact
Would the project:
a) Cause a substantial adverse change in the significance of a historical resource pursuant to §15064.5?

b) Cause a substantial adverse change in the significance of an archaeological resource pursuant to §15064.5?

c) Disturb any human remains, including those interred
outside of formal cemeteries?

Discussion: Consistent with PEIR Mitigation Measure CUL-1, Stantec has conducted a cultural resources assessment consisting of: (1) a cultural resources records search conducted by the South- Central Coastal Information Center (SCCIC) located at California State University Fullerton; (2) consultation with the Native American Heritage Commission (NAHC) and with interested Native American tribes identified by NAHC; and (3) a field survey of the project site.

On May 10, 2022, Stantec requested a cultural resources CHRIS archival records search from the SCCIC, located at California State University Fullerton. The record search was completed by the SCCIC and results received by Stantec on July 18, 2022. The SCCIC records search included a review of all previously recorded prehistoric and historic archaeological sites located within the study area, as well as a review of all known cultural resource surv ey reports, excavation reports and regional cultural overviews. The purpose of the records search was to determine the number of cultural resource studies and known archaeological resources in the project area (26 acres), and the ½-mile radius study area. The record search returned 13 reports pertaining to previous studies conducted within the study area. Additionally, as part of the records search the following sources were reviewed:

 Google Earth Imagery
 Historical Aerial Imagery
 BLM General Land Office Records
 Built Environment Resource Directory (BERD)
 Cucamonga, CA (1897; 1900; 1903; 1944) 1:62,500 USGS topographic map  La Verne, CA (1928; 1940) and Onta rio, CA (1954; 1967; 2012) 1:24,000 USGS 7.5- minute topographic maps

On June 6, 2022, Stantec conducted a Phase I archaeological investigation on behalf of the City of Pomona for the proposed project. The archaeological investigation consisted of an archival records search of the entire 26-acre pr oject area and a surrounding ½-m ile study area, as well as an intensive pedestrian survey of the en tire project area. Th e report entitled, Archaeological Survey of Approximately 26 Acres of Land on Behalf of the City of Pomona, for the Proposed Pedley Section 2 – Environmental Analysis
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Spreading Grounds Pond Enhancements Project, Claremont, Los Angeles County, California , is on file with the City of Pomona.

a) Less than Significant Impact wi th Mitigation Incorporated. The records search revealed that one historic period resource, Mojave Road (Base Line Road) (P-19-187085), was previously recorded in the project area and one multicompone nt site, Indian Hill (P-19- 000108), was previously recorded within the study area. Indian Hill is located entirely outside of the project area and will be avoided. As a re sult of the intensive pedestrian survey, one historic building (PED-BC-02 - the Pedley Filtra tion Plant) and one hist oric distribution line (PED-BC-01 - 12KV Pitzer Distribution Line Segment) were observed.

The project does not propose changes or modificati ons to the historic building or the historic distribution line. To prevent potentially signifi cant impacts to these resources, Mitigation Measure CR-1 will be implemented to avoid these features during project construction.

The Mojave Road (P-19-187085) is aligned with the modern-day Base Line Road, an actively used throughfare. No furthe r cultural resources study is recommended for P-19-187085.

Therefore, with avoidance of the historic building and distri bution line, there would be no impacts to historical resources.

Mitigation Measure

The following mitigation measure would reduce project-related impacts on historic resources to less than significant levels.

CR-1 Historic Resources Avoidance . During project construc tion, no earthwork or other construction activity shall occur which disturbs the Pedley Filtration Plant or the historic distribution line (PED-BC-01 - 12KV Pitzer Distribution Line Segment). In the event that these structures cannot be avoided, additional evaluation would be required.

b) Less than Significant Impact wi th Mitigation Incorporated. The proposed project would require excavation for basin enhancement, be rm road improvements at PSG, storm drain improvements in Mills Avenue and improveme nts at Chaparral Park. No archaeological resources were observed or are known for thes e locations. However, in areas of deeper excavation there is the potential of encounterin g native soils and some limited potential to encounter previously unknown cultural resources. If artifacts are present in native soils, a limited potential exists for project construction to significantly impact the resources.

Maintenance of the PSG would be limited to the immediate surface of the basin bottoms and side slopes, no disturbance of native soils would be anticipated. Operation of the project would therefore have no impact on cultural resources.

Implementation of mitigation measures CR-2 and CR-3 would protect unknown cultural resources during installation of project facilities. As mitigate d, impacts on cultural resources would be less than significant.

Section 2 – Environmental Analysis

February 2023 Initial Study
Mitigation Measures

The following mitigation measur es would reduce project-rela ted impacts on archaeological resources to less than significant levels.

CR-2 Archaeological Awareness Training. All construction workers and supervisors shall attend a mandatory workshop providing information on cultural resources that may be present in the project vicinity; penalt ies for unauthorized co llection of artifacts; and the need to temporarily redirect work away from the loca tion of any unanticipated discovery until it is recorded and adequately documented and treated. The presentation shall be available to train additional personnel who may join the construction crew after the initial training.

CR-3 Unanticipated Discoveries . If previously unrecorde d cultural resources are encountered at any time during project construction, all work shall cease within 60 feet of the discovery until the find can be evaluated by a qualified archaeologist who meets the Secretary of the Interior standards. Work on the other portions of the project outside of the buffered area may continue during this assessment period. If determined to be potentially significant, and if the resource cannot be avoided, a Monitoring an d Treatment Plan shall be developed within 48-hours of the discovery. Appropriate Native Americans as identif ied by the NAHC would be notified of the find and provi ded a copy of the draft Monitori ng and Treatment Plan so as to provide Tribal input with regards to signif icance and treatment of the find. Work shall not resume in areas determined by the archaeologist as sensitive until th e discovery has been evaluated and the recommendations for treatment have been implemented.

c) Less than Significant Impact wi th Mitigation Incorporated. No recorded cemeteries are known for the project area. In the unexpected event that human remains are discovered during project construction or operation, the County Cor oner shall be contacted, the area of the find would be protected, and provi sions of State CEQA Guidelin es Section 15064.5 and Public Resources Code 5097 would be followed. With implementation of Mitigation Measure CR-4, project-related impacts on human remains potentially present in the project area would be less than significant.

Mitigation Measure

The following mitigation measure would redu ce project-related im pacts on unexpected discover of human remains to less than significant levels.

CR-4 Unanticipated Human Remains. In the unexpected event that human remains or funerary objects are uncovered at a project si te, there shall be no further excavation or disturbance of the site or any nearby area re asonably suspected to overlie adjacent human remains (minimum of 200-ft buffer of the find) until:
 The coroner of the county in which the remains are discove red must be contacted to determine whether an investigation of the cause of death is required, and  If the coroner determines the remains to be Native American:
 The coroner shall contact the Native American Heritage Commission within 24 hours.

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Initial Study February 2023
 The Native American Heritage Commission shall identify the person or persons it believes to be the most likely descended from the deceased Native American.  The most likely descendent may make recommendations to the landowner or the person responsible for the excavation work, for means of treating or disposing of, with appropriate dignity, the human remains and any associated grave goods as provided in Public Resources Code Section 5097.98.
 Where the following conditions occur, the City of Pomona or authorized representative shall rebury the Native American human re mains and associated grave goods with appropriate dignity on the property in a lo cation not subject to further subsurface disturbance:
 The Native American Heritage Commission is unable to identify a most likely descendent or the most likely descendent failed to make a recommendation within 24 hours after being notified by the commission;
 The descendant identified fails to make a recommendation; or  The City of Pomona or authorized representative rejects the recommendation of the descendant, and the mediation by the Native American Heritage Commission fails to provide measures acceptable to the landowner.

For additional details regarding mitigation m easures associated w ith the unanticipated discovery of human remains and associated f unerary objects, refer to Section 2.3.18 Tribal Cultural Resources, Mitigation Measure 4 (TCR-4).

With implementation of the a bove mitigation measures, projec t-related impacts on cultural resources would be less than significant.

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February 2023 Initial Study

2.3.6 Energy
Issues and Supporting Information Sources
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporated
Less Than
Significant
Impact
No
Impact
Would the project:
a) Result in potentially sign ificant environmental impact due to wasteful, inefficient, or unnecessary consumption of energy resources, during project construction or
operation?

b) Conflict with or obstruct a state or local plan for
renewable energy or energy efficiency?

Discussion: Energy consumption related to the proposed project w ould include fuel use for enhancement of the PSG basins, improvements to the storm drain system, installation of additional amenities at Chaparral Park, and maintenance of project facilities. a) Less Than Significant Impact. Project Construction Energy Consumption. Energy for project construction would be consumed in the form of fossil fuels for vehicles and equipment.

Specific volumes of gas and diesel would depend on the size and age of equipment selected by the construction contractor, the number of hours of active work each day for each vehicle or piece of equipment, and the overall constructi on schedule. The construction schedule and the equipment selected for use by the contractor would be overseen by the city of Pomona Construction Manager. To the extent feasible , efficiencies in sche duling and equipment use would minimize the fossil fuels used during construction.

Project Operations Energy Consumption. Pr oject operation would also result in the consumption of fossil fu els for maintenance of the basins. Vehicles and equipment used for maintenance would be properly maintained to maximize energy efficiency.

Overall, the project would increase the reliability of local water supply, an energy savings over increased imported water use in the City of Pomona service area. Since construction and operation of the project would not be wasteful, inefficient, or unnecessary, the project would have a less than significant impact on energy use.

b) No Impact. The planning document relevant to renewable energy or energy efficiency is the Claremont General Plan (Claremont, 2009). Claremont supports sustainable building practices and energy conservation.

The project includes new buried storm drain fac ilities, but would not include development of new buildings. Since the project would increase the reliability of local water supply, it would not conflict with General Plan energy conservation policies.

For water agencies, greenhouse gas reductions focus on the relationship between water and energy. A Greenhouse Gas Emissions Calculator developed by Un ited States Bureau of Section 2 – Environmental Analysis
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Initial Study February 2023
Reclamation (2013) showed that an effective way to reduce the volume of carbon emissions related to water treatment and meet Assembly Bill (AB) 32 goals would be to reduce imported water usage and increase loca l supply usage and water use efficiency. Since the proposed project would increase the reliability of local water supply, the project would not conflict with or obstruct a state or local plan for renewable energy or energy efficiency; there would be no adverse impacts on energy planning.

Section 2 – Environmental Analysis

February 2023 Initial Study

2.3.7 Geology and Soils
Issues and Supporting Information Sources
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporated
Less Than
Significant
Impact
No
Impact
Would the project:
a) Directly or indirectly caus e potential substantial adverse effects, including the risk of loss, injury, or death
involving:

i) Rupture of a known earthquake fault, as delineated
on the most recent Alquist-Priolo Earthquake Fault
Zoning Map issued by the State Geologist for the
area or based on other substantial evidence of a
known fault? Refer to Division of Mines and
Geology Special Publication 42.

ii) Strong seismic ground shaking?
iii) Seismic-related ground failure, including
liquefaction?

iv) Landslides?
b) Result in substantial soil er osion or the loss of topsoil? c) Be located on a geologic unit or soil that is unstable, or that would become unstable as a result of the project,
and potentially result in on- or off-site landslide, lateral spreading, subsidence, liquefaction, or collapse?

d) Be located on expansive soil, as defined in Table 18-1-B of the Uniform Building Code (1994) creating substantial direct or indirect risks to life or property?

e) Have soils incapable of adequately supporting the use of septic tanks or alternative wastewater disposal systems, where sewers are not available for the disposal of
wastewater?

f) Directly or indirectly destroy a unique paleontological resource or site or unique geologic feature?

Discussion: The project area is located at the northern end of the Peninsular Ranges geomorphic province. The Peninsular Ranges formed as a volcan ic island arc collided with the west coast of North America and was accreted onto the margin of the continent, resulting in the expansion of the continent westward. The Penins ular Ranges are part of a larger subduction zone that extends all along western North America, with this particular geomorphic province extending from the Los Angeles Basin in the north to Baja in the south, and extending to Santa Ca talina, Santa Barbara, San Nicolas, and San Clemente Islands on the we st and the Colorado Dese rt on the east (Norris and Webb, 1990). The core of the Peninsular Ranges formed as the core of a magmatic arc in the Mesozoic that resulted from active subduction along the Pacific Plate boundary (Harden, 2004).

Locally, the project area is in the Los Angeles Basin, a structural depression approximately 50 miles long and 20 miles wide in the norther nmost Peninsular Range s Geomorphic Province (Ingersoll and Rumelhart, 1999). The Los Angeles Ba sin developed as a resu lt of tectonic forces Section 2 – Environmental Analysis
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and the San Andreas fault zone, with subsidence occurring 18 – 3 million years ago (Ma) (Critelli et al., 1995). While sediments dating back to the Cretaceous (66 Ma) are preserved in the basin, continuous sedimentation began in the middl e Miocene (around 13 Ma) and continues today, resulting in thousands of feet of accumulation (Yerkes et al., 1965). Most of these sediments are marine, until sea level dropped in the Pleistocene and deposition of the alluvial sediments that compose the uppermost units in the Los Angeles Basin began.

As noted in the Strategic Plan PEIR (TVMWD, 2021), the Six Basins are located across a major watershed divide that separates the San Gabriel River watershed to the west from the Santa Ana River watershed to the east. The stream systems that exit the San Gabriel Mountains comprise the main source of sediments and water that contributed to the formation of the Six Basins. The largest of these stream systems is San Antonio Creek, which is responsible for the deposition of material that created the broad alluvi al fan, emanating from the m outh of San Antonio Canyon. Soils associated with the geology in the Six Basins project area are made of alluvial material generally consisting of boulders, cobble, gravel, sand, silt and clay.

a)-i) and a)-ii) Less Than Significant Impact. The project area is not mapped within a currently designated State of California Earthquake Fault Zone (formerly Alquist-Priolo Special Studies Zones) for surface fault rupture. However, the project site is bounded by the Sierra Madre Fault and Rancho Cucamonga Fault system (zoned as active) to the north and by the Indian Hill Fault and San Jose Fault system to the south. K nown faults within 50 km of the site have a maximum moment magnitude of up to 7.9. Theref ore, seismic ground shaking is possible for the project site and surrounding region. However, based on location and geologic conditions, the potential for surface rupture re sulting from the movement of n earby faults is considered low (Converse Consultants, 2022).

Storm drain improvements and vault design would be done consistent w ith relevant seismic code requirements (California Building Code) and guidance documents such as the Minimum Design Loads and Associated Criteria for Buildings and Other Structures (ASCE/SEI 7-16, 2017). Design features to limit seismic impacts could include flexible pipe couplings and seals.

Since habitable structures would not be built as part of the proposed project, people would not be exposed to adverse effects involving seismi c ground shaking. Damage to project facilities would be repaired as necessary. Therefore, imp acts related to seismic events would be less than significant.

Relevant to the Strategic Plan PEIR mitigation meas ures, the proposed proj ect is not located within a State of California Earthquake Faul t Zone and therefore Measure GEO-1 does not apply. A geotechnical investigation has been completed for the project (Converse Consultants, 2022) and recommendations incorporated into the project design. Therefore, Measure GEO-2 has been completed.

a)-iii) Less Than Significant Impact. Soils with moderate liquefaction susceptibility (sediments are young (less than 10,000 years old), unconsolidated, with fine-grained layers, and there has been artesian well activity historically) are mapped to the north and southwest of the PSG (Claremont, 2009). The potential for liquefaction has been found to be the greatest where the groundwater levels and loose cohesionless soil s occur within 50 feet of the ground surface.

Section 2 – Environmental Analysis

February 2023 Initial Study
The project site is not located within a mapped Seismic Hazard Zone for potential liquefaction (Converse Consultants, 2022). Sin ce the project would not be co nstructed in an area with liquefaction susceptibility, and since habitable structures would not be built as part of the proposed project, people would not be exposed to adverse effects invo lving seismic-related ground failure. Damage to projec t facilities from seismic even ts would be repaired as necessary. Therefore, impacts related to ground failure would be less than significant.

a)-iv) Less Than Significant Impact. Areas susceptible to earth quake-induced landslides are mapped north of the project site (Claremont, 2009). The project site is located well away from the mountain front, and the pot ential for seismically-induced landslides to impact the project site is low (Converse Consultants, 2022). Additionally, since habitable structures would not be built as part of the proposed project, people would not be exposed to adverse effects involving landslides. Damage to project facilities would be repaired as necessary. Therefore, impacts related to landslides would be less than significant.

b) Less Than Significant Impact. PSG site soils are characterized as well drained soils with high infiltration rates and low runoff potential (TVMWD, 2021). Soil disturbance would occur during excavation for the basins and storm drain improvements, and during basin maintenance.

Site preparation for storm drain improvements would be unlikely to impact topsoils since these would have been removed dur ing previous ground disturban ce. Basin grading and vault installation would be done in compliance with BMPs, including measures to control erosion from the construction area. Basin maintenanc e would manage accumulated sediments but largely leave native soils intact. With compliance with stormwater regulations, impacts related to erosion and loss of topsoil would be less than significant. c) Less Than Significant Impact. Based on review of geologic conditions and topography (graded slopes) at the site and vi cinity, the potential for lateral sp reading at the project site is considered low (Converse Consul tants, 2022). The site is not located within a designated earthquake-induced landslide zone and the potential for seismically-induced landslides to impact the project site is low. The site is not located within a designated liquefaction zone (Claremont, 2009) and the projec t site not susceptib le to potential liquefaction (Converse Consultants, 2022). Therefore, impacts related to unstable geologic units or soils would be less than significant.
d) Less Than Significant Impact. The type and amount of clay present in soils, along with moisture content, determine the expansive potential of soils. The project site is in an area of poorly consolidated alluvium from the Sa n Gabriel Mountains (Claremont, 2009). The Uniform Building Code (ICBO, 1994) defines an Expansion I ndex of soils, which guides foundation design. During geotechnical investigation of the project site, the fill soils from 1 to 2 feet in depth below grade were found to cons ist primarily of silty sands and sands with varying amounts of gravels and cobbles (Converse Consultants, 2022). The native alluvial soils encountered beneath the fill were primarily alluvial fan deposits - coarse-grained soils consisting of silty sands, sands, sand and gravel mixes, sandy silts, clayey sands, and silty clays with varying amounts of gravels, cobbles, and some boulders.

Based on laboratory testing conducted as part of the geotechnical investigation, the expansion potential of the on-site surficial soils is ve ry low. Mitigation for expansion soils was not Section 2 – Environmental Analysis
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Initial Study February 2023
identified or considered necessary unless expa nsive site soils are en countered during grading (Converse Consultants, 2022). Design of the proj ect facilities would cons ider soil conditions and include appropriate design feat ures as relevant. Therefore, im pacts related to unstable or expansive soils would be less than significant.
e) No Impact. Sanitation facilities are not present or proposed for the project site. Therefore, there would be no impact on soils related to wastewater disposal. f) Less than Significant Impact with Mitigation Incorporated. Paleontological remains are considered limited, nonrenewable , scientific, and educational resources. Fossils can qualify as unique resources because they represent the best examples of specific species found in the region, particularly if they are discovered in an undisturbed context. Fossils can also qualify as unique paleontological resources because th ey provide evolutionary, paleoclimatic, or paleontological data important to the understanding of geologic history (SVP, 1996).

Consistent with PEIR Mitigation Measure GEO-3, Stantec has assessed the potential sensitivity of the project site for paleontological resources and prepared a Paleontological Resource Assessment for the PSG project (Appendix C).

The paleontological resource inve stigation consisted of a muse um records search from the Natural History Museum of Los Angeles County of the project area and vicinity, as well as a review of the most recent geologic mapping, relevant scientific literature and reporting, and a search of online collections databases. This research was used to assign paleontological potential rankings of the Society of Vertebra te Paleontology (2010) to the geologic units present in the project area, either at the surf ace or in the subsurface. The results of this assessment indicate that young alluvial fan depo sits are mapped in the project area, which have low-to-high paleontological potential, increasing with depth. These sediments are likely underlain by very old alluvial fan deposits in the subsurface, which are assessed as having high paleontological potential. Project plans fo r ground disturbance involve regrading of the existing pond basins and potholing to expose the existing utilities. Of these, the regrading of the existing basins may occur in geologic un its with high paleontological potential and therefore may encounter paleontological re sources. In order to reduce impacts to paleontological resources to a less than significant level, mi tigation measures GE-1 through GE-4 shall be implemented.

Mitigation Measures

The following mitigation meas ures would reduce pr oject-related impacts on paleontological resources to less than significant levels.

GE-1 Paleontological Monitoring and Mitigation Plan. A paleontologist meeting professional standards as define d by Murphey et al. (2019) sha ll be retained as the Project Paleontologist to oversee all aspects of paleontological mitigation, including the development and implementation of a Paleontological Monitoring and Mitigation Plan (PMMP) tailored to the project plans that provides for paleont ological monitoring of earthwork and ground disturbing activities into undistur bed geologic units with high pa leontological potential to be conducted by a paleontological monitor meeting industry standards (Murphey et al., 2019). A Section 2 – Environmental Analysis

February 2023 Initial Study
final monitoring report summarizing the results of the monitoring program should be prepared at the conclusion of project ground disturbance.

GE-2 Workers’ Environmental Awareness Training. The PMMP shall include provisions for a Workers’ Environmental Awareness Training Program that communicates requirements and procedures for the inadvertent discovery of paleontological resources during construction, to be delivered by the paleontol ogical monitor to the constructi on crew prior to the onset of ground disturbance.

GE-3 Paleontological Monitoring. The PMMP shall provide fo r full time pa leontological monitoring of grading in the existing basins at any dept h, and of other ground disturbing activities that exceed 5 feet in depth below the natural ground surface in previously undisturbed sediments. The Project Paleontologist may reduce the frequency of monitoring or spot checks should subsurface conditions indicate low paleontological potential.

GE-4 Paleontological Resource Salvage. Should a potentia l paleontological resource be identified in the project area, whether by the monitor or a member of the construction crew, work should halt in a safe radius around the find (usually 50 feet) until the Project Paleontologist can assess the find and, if si gnificant, salvage the fossil for laboratory preparation and curation at the Natural History Museum of Los Angeles County.

With implementation of mitigation measures, project-related impacts on paleontological resources would be less than significant.

Section 2 – Environmental Analysis
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2.3.8 Greenhouse Gas Emissions
Issues and Supporting Information Sources
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporated
Less Than
Significant
Impact
No
Impact
Would the project:
a) Generate greenhouse gas emissions, either directly or indirectly, that may have a significant impact on the
environment?

b) Conflict with an applicable plan, policy or regulation adopted for the purpose of reducing the emissions of
greenhouse gases?

Discussion: Greenhouse gases (GHGs) are gases that trap heat in the atmosphere. The most common GHGs emitted from natural processes and human activities include carbon dioxide (CO2), methane (CH 4), and nitrous oxide (N 2O). Examples of GHGs creat ed and emitted primarily through human activities include fluorinated gases (hydrofluorocarbons and perfluorocarbons) and sulfur hexafluoride. Each GHG is assigned a global warming potential. The global warming potential is the ability of a gas or aerosol to trap heat in the atmosphere. The global warming potential rating system is standardized to CO2, which has a value of one. For example, CH4 has a global warming potential of 21, which means that it has a global warming effect 21 times greater than CO2 on an equal-mass basis. Total GHG emissions from a source are often reported as a CO2 equivalent (CO2e). The CO2e is calculated by multiplying the emission of each GHG by its global warming potential and adding the results together to produce a single, co mbined emission rate representing all GHGs. On a national scale, federal agencies are addressing emissions of GHGs by reductions mandated in federal laws and Executive Orders. Several states have promulgated laws as a means to reduce statewide levels of GHG emissions . In particular, the California Global Warming Solutions Act of 2006 (AB 32) directed the State of California to reduce statewide GHG emissions to 1990 levels by the year 2020.

AB 32 requires CARB, in coordination with other State agencies and members of the private and academic communities, to adopt regulations to require the reporting and verification of statewide GHG emissions and to monitor an d enforce compliance with this program. Under the provisions of the bill, by 2020, statewide GHG emissions were to be limited to the equivalent emission levels in 1990. On December 12, 2008, CARB adopted its Climate Change Scoping Plan pursuant to AB 32 (CARB, 2008). The Scoping Plan was re-a pproved by CARB on August 24, 2011, and in November 2017, CARB adopted the final 2017 Scoping Plan: The St rategy for Achieving California’s 2030 GHG target. The 2017 Scoping Pl an indicates existing and ongoing emission reduction efforts and identifies new policies and actions to accomplish the State’s climate goals.

According to CARB (2019), in 2017, CO
2 accounted for approximately 83 percent of statewide
GHG emissions, with CH 4 accounting for approximately 9 percent of GHG emissions and N 2O accounting for another 3 percent of GHG e missions. Fluorinated gases accounted for approximately 5 percent of GHG emissions in California in 2017. The transportation sector is the Section 2 – Environmental Analysis

February 2023 Initial Study
single largest category of Cali fornia’s GHG emissions, accounti ng for 40 percent of emissions statewide (CARB, 2019). In 2017, to tal California GHG emissions we re 424 million metric tons of CO2e (MMTCO2e), 5 MMTCO 2e lower than 2016 levels and 7 MMTCO 2e below the 2020 GHG Limit of 431 MMTCO2e (CARB, 2019).

a) Less Than Significant Impact. Project-related GHG emissions would be limited to air pollutants generated from equipment and vehicl es during construction and maintenance of project facilities. As described in Section 2.3.3 Air Quality, construction of the project would result in less than significant combustion emissions from vehicles and equipment.

The proposed project is loca ted within the jurisdiction of the SCAQMD. In 2008, the SCAQMD release draft guidan ce regarding interim CEQA GHG significance thresholds.

Within its October 2008 documen t, the SCAQMD proposed the use of a percent emission reduction target to determine significance for commercial/residential projects that emit greater than 3,000 MT CO2e per year. Under this prop osal, a commercial/residential threshold was not formally adopted. On December 5, 2008, th e SCAQMD Governing Board adopted the staff proposal for an interim GHG significance of threshold of 10,000 MT CO 2e per year for
stationary source/industrial projects where the SCAQMD is the lead agency, with construction emissions amortized over 30 y ears and added to ope rational GHG emissions.

However, the SCAQMD has yet to adopt a GHG significance threshold for land use development projects.

Based on the estimated average day construc tion emissions, emissions of GHG related to construction of the proposed project are summarized in Tabl e 10. While the SCAQMD thresholds have not yet been approved, the a nnual construction emissions can be compared against the proposed 3,000 MT CO
2e/year threshold. Since predicted project GHG emissions would be substantially less than this threshol d, project-related emissi ons would not have a significant direct or indirect impact on GHG and therefore th e project would not have a significant impact on climate change.

Table 10. Estimated Construction Greenhouse Gas Emissions (Unmitigated) Construction Year MTCO2e
2023 239
Total 239
Amortized over 30 years 8.0
Notes:

MTCO2e = metric tons of CO2 equivalent
Source: CalEEMod Output (Appendix A), unmitigated emissions

Once operational, the project would result in periodic vehicle and equipment emissions related to basin maintenance and staff inspections of the facilities, similar to existing conditions. The project does not include any substantive new stationary or mobile sources of emissions. The Section 2 – Environmental Analysis
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Initial Study February 2023
impact of project operation on em issions of GHG, and thus cl imate change, would be less than significant.

b) Less than Significant Impact. In February 2022, the Claremont City Council voted to switch to a 100 percent Green Power program through the Clean Power Alliance where all of the city’s electricity will come from renewable sources such as solar, wind and geothermal. The Clean Power Alliance is a nonprofit joint power s authority comprised of 32 public agencies across Ventura and Los Angeles counties.

For water agencies, greenhouse gas reductions focus on the relationship between water and energy. Operation of the proposed project would not have any additional substantial demand for electricity. Energy use and air emissions related to the proposed project would occur primarily during construction, with periodic emissions during facility maintenance (as under existing conditions). The project would not gene rate substantial new vehicle trips or GHG emissions. Additionally, reduced imported water usage and increased local supply usage have been identified as effective ways to reduce the volume of carbon emissions related to water treatment and meet AB32 goals (Bureau of Reclamation, 2013). Therefore, the project would not conflict with an applicable plan, policy, or regulation adopted for the purpose of reducing the emissions of GHGs; impacts would be less than significant.

Section 2 – Environmental Analysis

February 2023 Initial Study

2.3.9 Hazards and Hazardous Materials
Issues and Supporting Information Sources
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporated
Less Than
Significant
Impact
No
Impact
Would the project:
a) Create a significant hazard to the public or the
environment through the routine transport, use, or
disposal of hazardous materials?

b) 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?

c) Emit hazardous emissions or handle hazardous or
acutely hazardous materials, substances, or waste within one-quarter mile of an existing or proposed school?

d) 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 it create a significant hazard to the public or the environment?

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?

f) Impair implementation of or physically interfere with an adopted emergency response plan or emergency
evacuation plan?

g) Expose people or structures, either directly or indirectly, to the risk of loss, injury or death involving wildland fires?

Discussion: Existing use of hazardous materials at the PSG includes gasoline and diesel fuel for operations equipment and vehicles.

Vectors. Under existing conditions, since water from the PFP is continuously replaced and basins have high infiltration rates, mosquito controls have not been required at PSG. For design of the proposed project, a review of vector minimization considerations has been conducted (Table 11).

Note that dry systems are any structure designe d to drain completely following capture and/or treatment of runoff. Vector minimization will be incorporated into the O&M Plan for the PSG.

Table 11. Dry Systems Checklist of Vector Minimization Measures Checklist Item Response
Complete discharge of all captured water in 4 days or less. Yes Is the structure designed to discharge all captured water in 4 days or less? Yes Has every effort been made to trace and eliminate persistent non- stormwater flows (e.g. irrigation runoff) that may enter the system and jeopardize non-chemical vector control efforts?
Yes
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Checklist Item Response
Has groundwater depth been carefully evaluated to ensure that the structure will not be permanently or seasonally flooded (i.e., is the base of the basin higher than the local groundwater table)?
Yes
Does the design provide an adequate slope between the inlets and outlets, with special attention given to ensure corners are above grade? Yes, this design
consideration was
preliminarily evaluated and
will be considered during
the desi
gn phase
Has soil been compacted adequately during grading to minimize subsidence, which can result in pools of standing water? Yes, this design
consideration was
preliminarily evaluated and
will be considered during
the desi
gn phase
Does the design slope take into consideration the inevitable accumulation of sediment and debris between maintenance periods that can result in standin
g water, especially in and around the inlet?
Yes
Does the design minimize the use of features that increase the potential for standing water, such as loose riprap and concrete curbs? Yes Does the structure include a concrete or earthen low-flow channel to concentrate (i.e., minimize available surface area) and direct non- stormwater flows to the outlet?
Not Applicable
Is the distribution piping sloped adequately and smooth (not corrugated) on the inside to prevent standing water? Yes
Are the inlet structures and energy dissipaters designed and sloped sufficiently to prevent scour depressions?
Yes, this design
consideration was
preliminarily evaluated and
will be considered during
the desi
gn phase
Are the outlets designed with debris screens or other features that reduce the potential for clogging? Yes
Is the structure designed with safe and sufficient access for inspection, maintenance, and/or vector control activities when needed? Yes Does the operation and maintenance plan include a minimum of quarterly inspections to ensure that vegetation overgrowth, sediment accumulation, or other factors have not created areas of standing water? Yes
Does the operation and maintenance plan include a minimum annual maintenance to remove vegetation overgrowth, remove sediment and debris accumulation, and otherwise return the structure to “as-designed” conditions?
Yes
Is signage provided and clearly visible with minimum information indicating the type of structure (e.g. extended detention basin), ownership, and contact information?
Yes

a) and b) Less Than Significant Impact with Mitigation Incorporated. Construction of the proposed project would require the routine transport, use, and storage of limited quantities of gasoline and diesel fuel for construction vehicles and equipment operation. Maintenance of the basins would also require gasoline and diesel fuel for heavy equipment. Additionally, as under existing conditions, herbicides such as glyphosate, prodiamine, and isoxaben may be used for vegetation management. Chemical mosquito controls are not currently required, and none are anticipated to be required for the project.

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February 2023 Initial Study
Operators would employ standard operating procedures for the routine transport, use, storage, handling, and disposal of hazardous materials related to the construction and operation of public works facilities. The use of fuels is an existing condition at the PSG. The use of herbicides for vegetation management or potentially larvicides for mosquito control would be conducted as per manufacturer’s recommendations. Therefore, with adherence to the standard operating procedures for hazardous materials use, impacts related to re lease or accidental exposure to humans or the environment would be less than significant.

Although mosquito controls have not been re quired for existing operations at PSG, expanded use of the basins would result in additional days of wetted area and potentially increased habitat for mosquitos, midges, or other vectors. Th erefore, mitigation measure HZ-1 shall be implemented to reduce impacts from vectors to less than significant levels.

Mitigation Measure

The following mitigation measure would reduce project-related impacts on vectors to less than significant levels.

HZ-1 Vector Management. The City of Pomona shall coordinate the San Gabriel Valley Mosquito and Vector Control District (SGVM VCD) to develop a strategy/plan to minimize the occurrence of vectors, such as midges an d mosquitos; and to establish protocols for monitoring and eradicating vector s should they be found when basi ns are in use (filled with water). Monitoring to determine presence/absenc e of vectors during periods when recharge basins are holding water shall be the responsibility of the City of Pomona to engage the services of a vector control professional. Should monitoring have positive results, the vector control professional shall work with the SGVMVCD to implement control measures as set forth in the approved strategy/plan. The strate gy/plan shall be prepared and available to be implemented prior to initiating the use of the expanded recharge basins.

c) Less Than Significant Impact. Several schools are located near the project areas including Chaparral Elementary School which is immediately adjacent and east of PSG at 451 Chaparral Drive. During project constructions, fu els would be used for vehi cles and equipment. Spill control prevention BMPs would be implemented during construction of the project. During basin maintenance, hazardous materials use w ould include fuels for eq uipment and vehicles and potentially herbicides for ve getation control. Fuel use w ould be confined to the PSG property. On-site spill control equipment would be present. Herbicides, if employed, would be applied only on the PSG property and per ma nufacturer’s recommendations. Since hazardous materials would not be used outsi de of the property of the basi ns and would be applied in a manner that controls travel off-site, the impact of the proposed project on hazardous materials release within ¼ mile of an existing or proposed school would be less than significant.

d) No Impact. Section 65962.5 of the California Government Code requires the California Environmental Protection Agency (CalEPA) to update a list of know n hazardous materials sites, which is also called the “Cortese List.” The sites on the Cortese List are designated by the SWRCB, the Integrated Waste Management Board, and the Department of Toxic Substances Control (DTSC).

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Based on a search of the data sources that provide information regarding the facilities or sites identified as meeting the “C ortese List” requirements, th ere are no hazardous waste and substances sites listed for the PSG (Table 12). Twenty-six leaking underground storage tank (LUST) sites are noted in Claremont, but all of these sites are completed, closed cases.

Table 12. Cortese List Databases and Results for City of Claremont Database Results Relevant to PSG
List of Hazardous Waste and Substances sites
from Department of Toxic Substances Control
(DTSC) EnviroStor database
No results in the City of Claremont
List of Leaking Underground Storage Tank Sites
from the SWRCB’s GeoTracker database

26 LUST cleanup cases noted for the City of
Claremont including one south of PSG at 1500
College Avenue North. Status of all completed –
case closed.

List of solid waste disposal sites identified by
Water Board with waste constituents above
hazardous waste levels outside the waste
mana
gement unit
No results in the City of Claremont
List of active Cease and Desist Orders and
Cleanup and Abatement Orders from the
Regional Board
No results in the City of Claremont
List of hazardous waste facilities subject to
corrective action pursuant to Section 25187.5 of
the Health and Safet
y Code, identified by DTSC
No results in the City of Claremont
Sources: SWRCB 2022; DTSC 2022; RWQCB 2022

e) Less Than Significant Impact. Airports near Claremont include Cable Airport in Upland (0.9 miles east of PSG), Bracket Field Airport in La Verne (4 miles west of PSG), and Ontario International Airport (6 miles southeast of PSG ). The PSG are located within Zone E of the Cable Airport Land Use Compatibility Plan (Upland, 2015) – the least restrictive compatibility zone. The project does not include new power poles or other tall structures that could pose a risk to airport safety. During construction, cranes in excess of 30 feet tall would not be required.

The surface area of ponds potential ly attractive to birds would not be substantially increased by the project, although the ponds may be wetted additional days per year. Since the PSG are an existing use, and the project would not resu lt in new tall structures or equipment, or a substantial increase in risks from wildlife, impacts on airpor t safety would be less than significant. Since the project doe s not include habitable struct ures, and since the workforce required for maintenance of PSG is not anticipat ed to substantially change, the project would not expose people residing or working in the area to experience excessive airport-related noise.

Impacts related to noise near an airport/airstrip would be less than significant.

f) Less Than Significant Impact. In the event of a disaster, specific evacuation routes in the City of Claremont are determined by the Cl aremont law enforcement agencies. Temporary lane closures during construc tion for storm drain improvement s could impact the movement of emergency vehicles. To protect public safety, flag workers will be placed at intersections near lane closures to direct traffic. Local emergency response agencies (Claremont Police Section 2 – Environmental Analysis

February 2023 Initial Study
Department and Claremont Fire Department,) would be notified of the timing and duration of planned lane closures. Since the project site is not designated as an emergency staging area, and since notifications to emergency providers would be conducted as part of the project, the project would have a less than significant impact on emergency access and evacuation plans.

g) Less Than Significant Impact. The project areas are not ma pped within a Fire Hazard Severity Zone (Claremont, 2009) and are located a mile south of wilderness areas. Fire stations in Claremont are located at 3710 N. Mills Avenue (Station 62), 606 W. Bonita Avenue (Station 101), 4370 Sumner Avenue (Station 102).

Use of welding equipment, if any during proj ect construction, would be conducted according to industry standards. Once the storm drain improvements are constructed and disturbed areas restored, the risk of fire along the storm drain alignment would be similar to existing conditions. Recharge of additional stormwater at the PSG could increase the number of days per year that the basins are we tted, a reduction in fire potential. Maintenance of the basins would include vegetation control, reducing poten tial fuel for fires. Th erefore, the proposed project would have a less than significant impact related to wildland fires.

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2.3.10 Hydrology and Water Quality
Issues and Supporting Information Sources
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporated
Less Than
Significant
Impact
No
Impact
Would the project:
a) Violate any water quality standards or waste discharge requirements or otherwise substantially degrade surface or groundwater quality?

b) Substantially decrease grou ndwater supplies or interfere substantially with groundwater recharge such that the
project may impede sustainable groundwater
management of the basin?

c) Substantially alter the ex isting 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 erosio n 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 offsite;

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?
d) In a flood hazard, tsunami, or seiche zones, risk release of pollutants due to project inundation?

e) Conflict with or obstruct impl ementation of a water quality control plan or sustainable groundwater management
plan?

Discussion: As described in the Strategic Plan PEIR , the Six Basins are part of a large broad alluvial plain located along the southerly extent of the mountains that sit atop a depression known as the Chino Plain, also known as the Perris Block. Soil deposits in the Six Basins project area are the result of deposition associated with sediments washing down from the San Gabriel Mountains along numerous drainages over time, coalescing and building to form the water bearing sediments that sit atop the bedrock (TVMWD, 2021).

Groundwater recharge to the Six Basins primarily occurs by:
 Infiltration of native and imported surface waters at the spreading grounds that overlie the Six Basins (San Antonio Creek, Thompson Creek, Live Oak, Pedley, and Miramar)  Subsurface inflow from the saturated alluvium and fractures within the bordering bedrock hills and mountains
 Deep infiltration of precipitation and applied water
 Deep infiltration of septic tank discharge
 Streambed infiltration in unlined channels
Section 2 – Environmental Analysis

February 2023 Initial Study

Groundwater quality in the Six Basi ns has been influenced by past agricultural uses (pesticides and herbicides), urban uses (gas and fueling st ations), and industrial si tes. Contaminants known from groundwater monitoring/testing in the Six Basins project area include: total dissolved solids, nitrate, perchlorate, trichloroethene (TCE), tetrachloroethene (PCE), 1,1-dichloroethene (1,1- DCE), and hexavalent chromium (Cr-6) and 1,2,3- trichloropropane (1,2,3- TCP). Specifically, groundwater contaminant plumes ar e known for three former industria l sites (two in the City of La Verne approximately 9 miles west-southw est from PSG and one in the Pomona Basin approximately 2 miles s outhwest of PSG). The PSG property is not located within a delineated groundwater contaminant plume associated with these or other industrial sources.

a) Less than Significant Impact with Mitigation Incorporated. The PSG are within the Upper Claremont Heights subbasin of the Six Basins groundwater ba sins. In the Water Quality Control Plan for the Los Angeles Region (Basin Plan) prepared by the Los Angeles Regional Water Quality Control Board (Regional Board, 2014, amended through 2020) the Six Basins are divided into three groundwat er subbasins, the PSG are w ithin the Claremont Heights subbasin. The designated beneficial uses for all three subbasins are: municipal and domestic supply, agricultural supply, industrial service supply, and industrial process supply.

Narrative and numeric water quality standards for all groundwaters in the region are applicable for: bacteria, chemical constituents and radio activity, mineral quality, nitrogen, and taste and odor.

Water quality objectives for the Claremont Heights groundwater subbasin are (Regional Board, 2014):
 Total Dissolved Solids (TDS) – 450 mg/L
 Sulfate – 100 mg/L
 Chloride – 50 mg/L

Project Construction. During project construction, disturbance to surface soils would result from grading of the basins, berm road creati on, improvements to the storm drain system, and construction of amenities at Chaparral Park. Since disturbance to surface soils would exceed 1 acre, stormwater would be managed in acco rdance with BMPs identified in a SWPPP completed in compliance with the NPDES General Permit for Storm Water Discharges Associated with Construction Ac tivity (General Permit). Example types of BMPs to be implemented are summarized in Table 13. Th e SWPPP would include a map to detail the locations of work zones and BMP placement. Additionally, dewatering is not currently anticipated to be required during project construction. In the event that dewatering is required, a permit would be obtained from the SWRCB. With implementation of mitigation measures HYD-1 and HYD-2, construction of the proposed project would not substantially increase sediment load in stormwater or adversely affe ct surface water beneficial uses. Therefore, the impact on water quality during project construction would be less than significant.

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Table 13. Summary of Anticipated Construction Stormwater BMPs Best Management Practices for the Protection of Stormwater Quality During Construction Housekeeping Measures
 Conduct an inventory of products used or expected to be used  Cover and/or berm loose stockpiled construction materials  Store chemicals in watertight containers
Employee Training
 Brief staff on the importance of preventing stormwater pollution  Have staff review SWPPP
 Conduct refresher training during the wet season
 Document training
Erosion and Sediment Controls
 Provide effective cover for inactive areas – co ver, berm, or direct runoff to suitable basins  Establish and maintain effective perimeter control
 Stabilize construction entrances and exits to contro l sediment – inspect ingress and egress points daily, and maintain as necessary
 Control dust during earthwork
 Place sandbags or other barriers to direct stormwater flow to suitable basins Spill Prevention and Control
 Inspect construction equipment for leaking
 Use drip pans until equipment can be repaired
 Cleanup spills Immediately – remove adsorbent promptly  Notify the proper entitie s in the event of a spill
Concrete Truck Washing Waste
 Provide containment for capture of wash water
 Maintain containment area
Hazardous Waters Management and Disposal
 Store hazardous wastes in covered, labeled contai ners with secondary containment for liquid hazardous wastes
 Store wastes separately to promote recycling and to prevent undesirable chemical reactions Materials Handling and Storage
 Establish a designated area for hazardous materials
 Berm, cover, and/or contain the stor age area as necessary to prevent materials from leaking or spilling  Store the minimum volume of hazardous materials necessary for the work Vehicle and Equipment Maintenance, Repair, and Storage
 Inspect vehicles and equipment regularly
 Conduct maintenance as necessary
 Designate areas for storage – where flui ds can be captured and disposed of properly Scheduling
 Avoid work during storm events
 Stabilize work areas prior to predicted storm events

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February 2023 Initial Study
Project Operation. Since the watershed areas above the Six Basins are within the San Gabriel mountains with no urban development, the quality of the surface water entering local spreading grounds is good (TVMWD, 2021). Implementation of the proposed project would further enhance the quality of recharge d stormwater. Basin 1 will be tr eated as a pre-sedimentation basin for the outflow from the PFP. Basin 2 will feature a large capacity water quality pretreatment device, inlet pipe extension with energy dissipater and stilling basin for debris and sediment captures.

Copper was determined to be the limiting pollutant for the ESGVWMG’S WMP. As described in the PDR, the anticipated copper reduction at PSG would be 100 percent (Table 14). With the enhanced treatment at PSG, the quality of water recharged at the project would be improved, a beneficial impact.

Table 14. Annual Average Pollutant Load Reduction for Proposed Conditions

Copper
Reduction
(pounds)
Copper Reduction
(%)
Proposed Conditions – Addition of flow from 30-inch
storm drain in Mills Avenue 22.45 100

Additionally, a groundwater under the direct influence of surface water hydrogeologic assessment was conducted to de termine if the surface water recharged at the PSG under the proposed project may impact th e quality of the groundwater pr oduced at the City’s Tunnel Wells (Appendix I of the PDR). A microscopic pa rticulate analysis (MPA) will be conducted to assess the existence of a hydraulic connection between the PSG and the Tunnel Wells. The timing of the MPA will be dependent on inform ation obtained from an intrinsic and/or introduced tracer study to estimate groundwater tr avel times and the relative percentage of recharge waters pumped at the Tunnel Wells. This analysis may be performed after project construction.

Maintenance. Project operation would include main tenance activities including removal of vegetation, silt, and debris from the basin. Many of the BMPs used during construction would also be implemented to maintain water quality. As described in the PEIR, mitigation measure HWQ-1 would be implemented during basin restoration projects.

With implementation of BMPs during project construction and as needed during maintenance, and with the stormwater quality improveme nts inherent in the design of the PSG enhancements, the proposed project would have less than significant impacts on groundwater and surface water quality.

Mitigation Measures
The following mitigation measur es would reduce impacts on water quality to less than significant levels.

HYD-1 Implementation of a SWPPP and the Use of BMPs During Construction. Prior to commencement of any ground dist urbing activities for the PSG project, the construction Section 2 – Environmental Analysis
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Initial Study February 2023
contractor shall prepare a SWPPP and submit a Notice of Intent (NOI) to the SWRCB.

Implementation of BMPs as outlined in th e SWPPP shall be on-going during construction activities. A copy of the SWPPP and the Waste Discharge Identification (WDID) number, shall be kept at the construction site and be available for review by inspectors until construction is completed.

HYD-2 Dewatering General Permit. Prior to commencement of construction activities that would require dewatering and conveyance of gr oundwater to surface water including but not limited to a storm drain system, a NOI sh all be submitted to the SWRCB under the requirements of the Dewatering General Per mit. The NOI shall include any additional information including a list of BMPs for preventing degradation of water quality or impairment of receiving waters.
b) Less than Significant Impact . The proposed project include s improvements to the storm drain system in the City of Claremont and enhancement of the PSG. With the project, capacity of the three basins will be 32.46 ac-ft. Based on a percolation rate of 6.22 in/hr, up to 35.33 ac- ft/day would be infiltrated. The project would enhance groundw ater recharge, a beneficial impact. The project does not include installation of new wells or groundwater withdrawals.

Therefore, the project would not substant ially deplete groundwater supplies or reduce groundwater recharge. Impacts on groundwater and management of the groundwater basin would be less than significant.

c) i) Less Than Significant Impact. The proposed project does not include alteration of the course of stream or river, or the addition of new impervious surfaces. Storm drains proposed to be improved as part of the project would convey runoff to the PSG in pipes; erosion of surface water features would not occur. Cons truction to enhance the PSG would temporarily disturb site soils for approxima tely 4 to 6 months. The poten tial for erosion during project construction would be minimized by implementat ion of BMPs included in the construction stormwater SWPPP. Therefore, the project would have a less than significant impact on erosion or siltation on- or off-site.
ii) Less than Significant Impact. Under the proposed project, adequate capacity for the 10- year storm event will be provided at PSG, based on:
 3.26 ac-ft/day from the 18-inch and 42-inch storm drains  7.64 ac-ft/day from the 30-inch storm drain
 13.26 ac-ft/day from the filtration plant can be accommodated as an emergency overflow, if necessary
Flows from larger storms would divert back to the existing storm drain system, as under existing conditions. During heavy storm events, th e PSG recharge basins would increase the capacity of the storm drain system by taking flows from local storm drains (TVMWD, 2021).

Therefore, the project would increase storage capacity at the PSG but would not increase flood risk. Impacts related to flooding would be less than significant. iii) Less than Significant Impact . The project includes impr ovements to the storm drain system and treatment of stormwater to impr ove water quality. No additional runoff from the PSG property would result as no new impervious surfaces are proposed. Flows in excess of the Section 2 – Environmental Analysis

February 2023 Initial Study
basins’ capacity would be conveyed in downstream storm drains, as under existing conditions.

Impacts on stormwater drainage systems would be beneficial and imp acts related to polluted runoff would be less than significant.

iv) Less than Significant Impact.

By design, the proposed project includes modifications to the storm drain system to dire ct flood flows to the PSG. Trea tment would reduce pollutants from these flows and the enhanced basins woul d facilitate increased groundwater recharge.

The proposed project would increase the capacity of the local storm drain system. Therefore, the project would have a less than significant impact on flood flows.

d) No Impact. Mapped as an Area of Minimal Flood Hazard, the PSG are not within a 100-year floodplain as mapped by the Federal Emergency Management Agency (FEMA) (TVMWD, 2021). The proposed project is designed to cap ture storm flows from existing storm drain systems in order to pretreat and recharge st ormwater into the groundwater basin. Under the proposed project, adequate capacity for the 10-year storm event will be provided at PSG. Flows from larger storms would divert back to th e existing storm drain sy stem, as under existing conditions. Therefore, the project would increase storage capac ity at the PSG but would not increase flood risk.

Due to the distance to the ocean, tsunami is not relevant for the proposed project. Seiches, or earthquake-generated waves are not known for the PSG. The proj ect would treat stormwater and remove surface water pollutants. Therefore, the project would have no impact on the risk of pollutant release in a flood, tsunami or seiche zone.

e) Less than Significant Impact. The proposed project would trea t and therefore enhance the quality of surface waters recharged to the Upper Claremont Heights groundwater subbasin. As a project to increase the volum e of groundwater recharge with high quality water, the project would be consistent with Basin Plan objectives.

As described in the PEIR (TVMWD, 2021), Senate Bills 1168 and 1319 and Assembly Bill 1739 amended the California Water Code to establish the Sustainable Groundwater Management Act (SGMA). The Act requires:
 the development of sustainable groundwater management plans for all medium- and high-priority basins, as defined by the Department of Water Resources  mandates the creation of local groundwater sustainability agencies to oversee and implement the plans
 outlines the guidelines and schedule for complying with the Act

Section 10721.8 of the amended Water Code exempts adjudicated areas and local agencies that conform to the requirements of an adjudication of water rights from the provisions of SGMA (specifically naming the Six Basins as exempt ) except for an annual reporting requirement.

The intent of the Strategic Plan is to continue to manage the groundwater basins in a reliable and sustainable way in order to ensure a continuous supply of water to the Watermaster Parties and their customers. As an element of the Strategic Plan, the PSG project is an integral part of a sustainable groundwater management plan. Since the proposed project would not conflict or obstruct implementation of a water quality control plan or sustainable groundwater Section 2 – Environmental Analysis
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management plan, the impact of the project on water resources planni ng would be less than significant.

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February 2023 Initial Study

2.3.11 Land Use and Planning
Issues and Supporting Information Sources
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporated
Less Than
Significant
Impact
No
Impact
Would the project:
a) Physically divide an established community?
b) Cause a significant environmental impact due to a
conflict with any land use plan, policy, or regulation
adopted for the purpose of avoiding or mitigating an
environmental effect?

Discussion:
a) Less than Significant Impact. The PSG are located within the City of Claremont.

Improvements to the PSG would be constructed on the existing site which is currently used for infiltration basins. During construction or th e storm drain improvements, access would be limited in the active area of construction, but once installed, the facilities would be buried and would not divide an established community. No habitable structures are planned as part of the proposed project. Therefore, impacts on established communities would be temporary and less than significant.

b) No Impact. The PSG are located on City of Pomona-o wned lands within the incorporated area of the City of Claremont. The PSG are designated as Public land use on the Land Use Plan of the City of Claremont’s General Plan (2014a), with a zoning of Park/Resource Conservation (P/RC) (Claremont, 2014b). These designations allow for public use including management of groundwater resources. The proposed project would improve existing facilities for the allowed uses of water recharge facilities and drainage channels. Therefore, the proposed project would have no impacts regarding conflicts with applicable planning documents.

Once installed, the storm drain improvements would be buried, and the land use of the project areas would be the same as existing conditions. With capture and infiltration of stormwater at the enhanced PSG, the project would be consiste nt with City of Claremont water resources goals. Since the project also includes enhancements at the adjacent Chaparral Park, the project would also be consistent with parks and open space goals. Therefore, construction and operation of the project would have no advers e impacts on land use planning, policies, or regulations.

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2.3.12 Mineral Resources
Issues and Supporting Information Sources
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporated
Less Than
Significant
Impact
No
Impact
Would the project:
a) Result in the loss of availability of a known mineral resource that would be of value to the region and the
residents of the state?

b) Result in the loss of availa bility of a locally-important mineral resource recovery site delineated on a local
general plan, specific plan, or other land use plan?

Discussion: The potential for aggregate mining occurs in Claremont based on its location at the edge of an alluvial fan that extends from the base of the San Gabriel Mountains. Several aggregate mining operations occur in the Claremont-Upland Production region, two just east of Claremont (Claremont, 2009). Mining also o ccurs north of the City, upstr eam from the San Antonio Creek Flood Control Dam.

Like the vast majority of the developed portion of the City of Claremont, the PSG sites is mapped as MRZ-2 – areas where adequate information i ndicates that significant mineral deposits are present or where a high likelihood exists for thei r presence (Claremont, 2009). However, the site is not mapped within an area of regional significance for mineral resources.

The City of Claremont is the lead agency for the implementation of the Surface Mining and Reclamation Act of 1975 (SMARA), which establishes statewide policies for the conservation and development of mineral lands in California. To prevent incompatible land use development in areas with significant mineral deposits, the Claremont General Plan (2009) includes the following goals and policies:

 Goal 5-17 Protect and conserve state-desi gnated significant min eral resources from land uses that threaten their availability fo r future mining and require that any future mining of those resources will not adversel y impact the environment or the livability of Claremont’s residential neighborhoods.
 Policy 5.17.1 Protect mineral resource depos its in designated areas of regional significance in order that such deposits ma y be available for future use, excepting in already urbanized locations where de velopment has already occurred or is planned.
 Policy 5.17.2 Balance the regional need to produce mineral resources against other City goals set forth in this General Plan.
 Policy 5.17.3 Balance the importance of mineral resources against alternative land uses and consider the value of minerals in their market region or to the state in reviewing any project involving mineral resources from areas designated regionally significant.

Section 2 – Environmental Analysis

February 2023 Initial Study
 Policy 5.17-4 Prior to approval of any use that would threaten the potential to extract from any state-designated signi ficant mineral resource, require that sufficient mitigation be provided to e liminate land us conflicts between the approved use and any future mining of the mineral resources.

a) and b) Less than Significant Impact. No active mining occurs on the project site but the area is designated as MRZ-2. The project includes enhancement of the existing basins and improvements to storm drains. Project oper ations would include basin maintenance, including vegetation management and periodic sediment and debris removal. However, the project would not otherwise alter the basins in a way that would prohibit future use of the site for mining. Since stormwater recharge at the basins would be consistent with existing site use and would not hinder the potential for future mining in the project area, the proposed project would have a less than significant impact on the loss of availability of a known mineral resource or mineral resource recovery site.

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2.3.13 Noise
Issues and Supporting Information Sources
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporated
Less Than
Significant
Impact
No
Impact
Would the project result in:
a) 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?

b) Generation of 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, would the project expose people
residing or working in the project area to excessive noise levels?

Discussion: Street and freeway (SR-210 and I-10) traffic, railways, and airports represent the primary sources of noise in Claremont (Claremont, 2009). Noise contours developed in 2005 for the General Plan (Claremont, 2009) note existing noise levels of 60 A-weighted decibels (dBA) Community Noise Equivalent Level (CNEL) at PSG. Claremont General Plan Policy 6-12.3 states:
 Minimize noise from property maintenance equipment, construction activities and other non transportation noise sources by enforcing designated construction and maintenance hours.

The Claremont Land Use Noise Guidelines for Land Use Planning (Claremont, 2009), allow for:

 Low to medium density residential (45 dBA interior, 65 dBA exterior)  High density residential (45 dBA interior, 70 dBA exterior)  Schools (50 dBA interior, 65 dBA exterior)
 Other Public/Institutional (50 dBA interior, 70 dBA exterior)

Relevant to construction activity, Chapter 16.154 Environmental Protective Standards Section 316.154.020 Noise and Vibration Standards of the Claremont Municipal Code notes the activities that are exempt from City noise standards, including:
 Noise sources associated with or vibration created by construction, repair, remodeling or grading of any real property, or during authorized seismic surveys, provided:
a. Activities take place between the hours of 7:00 a.m. and 8:00 p.m. weekdays and Saturdays, excluding national holidays; and
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b. Noise levels, as measured on residential properties, do not exceed 65 dBA for a cumulative period of more than 15 minutes in any one hour, 70 dBA for a cumulative period of more than 10 minutes in any one hour, 79 dBA for a cumulative period of more than 5 minutes in any one hour or 80 dBA at any time; and
c. Any vibration created does not endanger the public health, welfare, and safety.

Construction, repair, remodeling and grading activity that does not exceed the noise levels set by Section 16.154.020.D of Claremont’s Municipal Code may occur on Sundays and national holidays.

Ambient noise levels were quantified in the Six Basins PEIR (TVMWD, 2021). Relative to the PSG, the following noise levels were measured (Table 15).

Table 15. Ambient Noise Levels near PSG, Claremont, California Measurement
Site
Date Description Energy Average
Noise Level (dBA Leq)
Average Median
Noise Level (dBA Leq) CNEL
Daytime1 Nighttime Daytime Nighttime
L10-1 6/20/19 Chaparral Drive, east of
PSG, within a residential
neighborhood near
Chaparral Elementary
School

55.1 47.8 50.9 42.2 56.8
L10-2 6/20/19 Barrington Court, north of
PSG, within a residential
neighborhood near
Chaparral Park

54.3 47.1 50.1 45.3 56.0
Source: TVMWD, 2021
Notes: Daytime = 7:00 a.m. to 10:00 p.m.; Nighttime = 10:00 p.m. to 7:00 a.m.

a) Less Than Significant Impact wi th Mitigation Incorporated. The closest noise receptors to the project area are residences located immediately adjacent to the PSG and on Mills Avenue, and the immediately adjacent Chaparral Elementary School.

Construction. Temporary use of heavy construction equipment would occur within a few feet of residential property lines and within approxi mately 20 to 50 feet of structures, including school buildings. During improvements to the ba sins and installation of the storm drain improvements, noise would be generated from equipment with noise levels ra nging from approximately 74-90 dBA (at a distance of 50 feet) (Table 16).

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Table 16. Construction Equipment Noise Levels
Equipment Actual Measured Lmax @ 50 feet (dBA, slow)
(samples averaged)
Dump Truck 76
Jackhammer 89
Concrete Saw 90
Backhoe or Track Hoe 78
Front End Loader 79
Concrete Mixer Truck 79
Asphalt Paver 77
Roller Compactor 80
Vacuum Street Sweeper 82
Flat bed truck (delivery trucks) 74
Source: FHA, 2017
Lmax - the maximum sound level during a measurement period or a noise event

Based on the assumed construction schedules for the junction structure and the proposed vault, most receptors would experience construction noise for a few weeks at most. Noise would not be continuous as equipment would be used in termittently. Additionally, with an exterior-to- interior reduction of typical buildings of about 25 dB with windows closed (FTA, 2006), noise levels within homes directly adjacent to the construction would be anticipated to be on the order of 50 to 65 dBA.

To ensure that construction activity would adhere to the Claremont Municipal Code, regarding the Monday through Saturday acceptable work period, and the time limits for high noise generation activities, Mitigati on Measure N-1 would be imple mented. Construction activity would not occur during 7:00 p.m. to 6:00 a.m. when there is greater potential for noise disturbance to residents. Mitigation meas ures N-2, N-3 and N-4 would further reduce construction-related noise. As mitigated, noise generation during project construction would be consistent with established codes and noise impacts would be less than significant.

Operations. The closest noise receptors at PSG are dir ectly adjacent to the site. Operation of the proposed project would include periodic grading of basins and other maintenance activities.

Noise generated during project operation would be generated from tractors, backhoes, loaders, scrapers, dozers, power trimme rs, and manual tools. Howeve r, these activities would not generate substantial noise in excess of existi ng O&M activities. Maintenance noise would be infrequent and within the day a nd time restrictions noted in the Claremont Municipal Code.

Noise impacts during project operations would be less than significant. However, mitigation measure N-5 would be implemented to further reduce less than significant impacts.

Mitigation Measures

Implementation of the following mitigation measures would reduce noise and vibration levels during construction and operation of the proposed project to less than significant levels.

N-1 Construction Noise Plan. The construction contractor shall develop and implement a focused construction noise mitiga tion plan to ensure compliance with the City of Claremont Section 2 – Environmental Analysis

February 2023 Initial Study
construction noise limits established in M unicipal Code 16.154 Environmental Protective Standards Section 316.154.020. Where construction noise would exceed the noise levels and time periods specified, the constr uction contractor shall install temporary noise barriers, use alternative scheduling, or use alternative equipment. As part of the Noise Mitigation Plan, the City of Pomona will notify (at least 2 weeks in advance of the start of construction) residents and the Chaparral Elementary School adjacen t to the PSG and storm drain improvement locations as to the schedule for construction.

N-2 Construction Equipment Maintenance and Placement. During project site construction, the construction contractor shall ensure that all construction equipment, fixed or mobile, shall have properly operating and maintained mufflers, consistent with manufacturers’ standards. The construction contractor shall place all stationary construction equipment so that emitted noise is directed away from the noise-sensitive receivers nearest the project site.

N-3 Equipment Staging. The construction contractor shall locate equipment staging in areas that will create the greatest distance between construction-related no ise sources and noise- sensitive receivers nearest the project site dur ing all project construction (i.e., the center of each site).

N-4 Construction Haul Routes. The construction contractor shall design delivery routes for equipment and materials to minimize the exposu re of sensitive land uses or residential dwellings to delivery truck-related noise.

N-5 Operational Noise Minimization . All trucks transiting on-si te in outdoor areas of the project facilities shall be ope rated with properly functioning and well-maintained mufflers.

Pavement conditions at PSG shall be maintained to be free of vertical deflection (i.e., speed bumps) to minimize truck noise. Truck access gates and loading areas shall have posted signs which state:

1. Truck drivers shall turn off engines when not in use.

2. No music or electronically reinforced speech from workers shall be audible at noise- sensitive properties.

b) Less Than Significant Impact. Typical vibration (peak partic le velocity (PPV) at 25 feet) produced by construction and maintenance equipment includes sm all bulldozers at 0.003 (inches/second), loaded trucks at 0.076 inches/second, large bulldozers at 0.089 inches/second, and jackhammers at 0.035 inch es/second (FTA, 2006). The Federal Transit Administration (FTA) has published architectural damage cr iterion for continuous vibrations of 0.20 inch/second (FTA, 2006). Construction equipment necessary to install project facilities would create groundborne vibration and groundborne noise in the immediate area of the construction; vibration would be intermittent and not cont inuous. Since construction would not exceed the

0.20 inch/second PPV significance threshold for vibration, impacts related to temporary groundborne vibration or noise would be less than significant. Accordingly, PEIR Mitigation Measure NOI-5 would not be applicable to the proposed project.

c) Less than Significant Impact . Cable Airport in Upland is located approximately 0.9 miles east of PSG. The project areas are located with in Zone E of the Ca ble Airport Land Use Section 2 – Environmental Analysis
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Compatibility Plan (Upland, 2015) – the least restri ctive compatibility zone. The workforce for operations of the enhanced PSG is not anticipated to subs tantially change. Since the PSG are an existing use and no habitabl e structures are proposed as part of the project, the project would not expose additional peopl e residing or working in the area to experience excessive airport-related noise. Impacts related to noise near an airport/airstrip would be less than significant.

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2.3.14 Population and Housing
Issues and Supporting Information Sources
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporated
Less Than
Significant
Impact
No
Impact
Would the project:
a) Induce substantial unplanned population growth in an area, either directly (for example, by proposing new
homes and businesses) or indirectly (for example,
through extension of roads or other infrastructure)?

b) Displace substantial numbe rs of existing people or
housing, necessitating the construction of replacement
housing elsewhere?

Discussion:
a) Less Than Significant Impact. A project may induce growth if it would involve construction of housing or large employment centers or would remove barriers to population growth (e.g., a change to a jurisd iction’s General Plan and Zoning Ordinance that would allow new residen tial development to occur). The proposed project does not involve construction of any housing or employment centers, and would not modify the land use or zoning designations for the sites to permit new residential or commercial development. Construction at the PSG a nd for the storm drain improvements would generate some construction jobs, but this would be a temporary effect and would not provide permanent economic growth to the ar ea. Basin maintenance would also require workers, but the limited number and infrequent nature of basin maintenance would have a less than significant impact on employment in Claremont.

A project may also be considered growth -inducing if it increases the capacity of infrastructure in an area in which the public service currently meets demand. The proposed project would treat storm water runoff while recharging the groundwater basin to increase the reliability of local water supply. However, the project would not add new potable water wells or distribution systems, or add connections to new users. The project would not increase potable water delivery within the City of Pomona or City of Claremont service areas. Therefore, the proposed project would not significantly impact population growth.

b) No Impact. No habitable structures would be constr ucted as part of the project, and no existing housing would be removed. Therefore, the project would not displace existing people or housing and there would be no impacts on housing from construction and operation of the project.

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2.3.15 Public Services
Issues and Supporting Information Sources
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporated
Less Than
Significant
Impact
No
Impact
a) Would the project result in substantial adverse physical impacts associated with the provision of new or
physically altered governmental facilities, need for new or physically altered governmental facilities, the
construction of which could cause significant
environmental impacts, in order to maintain acceptable
service ratios, response times or other performance
objectives for any of the public services:

i) Fire protection?
ii) Police protection?
iii) Schools?
iv) Parks?
v) Other public facilities?
Discussion:
i – v) No Impact. New habitable structures are not proposed as part of the project. Similarly, the project would not induce population growth since it would not add new potable water wells or distribution systems, or add connections to new users. Neither the limited number of workers required to construct the proj ect (approximately 10), nor the operations-related maintenance workers (up to 1 additional worker, if any) w ould generate substantia l population growth or create the need for new or expanded public serv ices. Therefore, there would be no project- related impacts regarding new or physically altered fire, police, schools, parks, or other public facilities.

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2.3.16 Recreation
Issues and Supporting Information Sources
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporated
Less Than
Significant
Impact
No
Impact
a) Would the project increase the use of existing
neighborhood and regional parks or other recreational
facilities such that substantial physical deterioration of the facility would occur or be accelerated?

b) Does the project include recreational facilities or require the construction or expansion of recreational facilities which might have an adverse physical effect on the
environment?

Discussion: Located at 1899 North Mills Avenue, the City of Claremont Chapparal Park has a playground and soccer field. The proposed project includes new amenities for this park, potentially including new porous pavement walkway, minor planting of shrubs or native garden, viewing area with benches and educational signage about the PSG, wrought iron fenc ing, and a bike rack.

Details will be refined to reflect community input obtained during public outreach efforts.

a) Less Than Significant Impact. New habitable structures are not proposed as part of the project. The limited number of construction workers required to implement the project (approximately 10) would not gene rate substantial population grow th or create the need for new or expanded parks. Operatio n of the project would increase the volume of stormwater managed at PSG but would not impact adjacent recreational resources. Therefore, the project would have a less than significant impact related to increased use of neighborhood or regional parks or other recreation facilities.

Maintenance activities during operation of the pr oject would result in minor truck traffic (approximately 12 trucks per year), a less than significant impact on recreational access in the project area.

b) Less than Significant Impact.

The project includes improvements at Chaparral Park
potentially including new porous pavement walkway, minor planting of shrubs or native garden, viewing area with benches and educa tional signage about th e PSG, wrought iron fencing, and a bike rack. These improvements at an existing local park would have a beneficial, although less than significant, impact on recreation.

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2.3.17 Transportation
Issues and Supporting Information Sources
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporated
Less Than
Significant
Impact
No
Impact
Would the project:
a) Conflict with a program, plan, ordinance or policy
addressing the circulation system, including transit,
roadway, bicycle and pedestrian facilities?

b) Conflict or be inconsistent with CEQA Guidelines Section 15064.3 subdivision (b)?

c) Substantially increase hazards due to a geometric design feature (e.g., sharp curves or dangerous intersections) or incompatible uses (e.g., farm equipment)?

d) Result in inadequate emergency access?

Discussion: Relevant roadways to the project sites include:

 Mills Avenue – a four-lane north-south arterial, approximately 60 feet wide in the area of the proposed vault, with a Class II bike lane
 Baseline Drive – a four-lane east-west arterial, approximately 80 feet wide in the area of the proposed junction structure improvements, with a Class II bike lane

Additionally, materials and equipment would be brought to the project site, likely via I-10 and SR- 210. The specific routes for equipment and vehi cles would be dependent on the construction contractor selected for the work, and their fleet location.

a) Less than Significant Impact with Mitigation Incorporated . The Southern California Association of Governments (SCAG) pr epared the 2016 Regional Transportation Plan/Sustainable Communities Strategies (R TP/SCS) as part of regional transportation planning (SCAG, 2016). The RTP/SCS is a planning document that supports the integration of land use and transportation to help the region meet the federal Clean Air Act requirements.

The project would impact area roadways temporarily during construction and infrequently for the mobilization of maintenance equipment. However, since the project does not include new transportation systems or the permanent alteration of land use or roadways, the project would not conflict with the RTP/SCS.

General Plan . Relevant City of Claremont Genera l Plan goals and policies related to transportation include:
 Goal 4-7 Reduce congestion in areas surrounding schools and parks.

During construction the project could tempor arily increase congestion at the adjacent Chaparral Elementary School and Chaparral Park. With implementation of mitigation Section 2 – Environmental Analysis

February 2023 Initial Study
measures TR-1 (Construction Traffic Management Plan), TR-2 (Heavy Equipment Travel) and TR-3 (Haul Trucks), impacts on local schools and parks would be te mporary and less than significant.

 Goal 4-8 Maintain truck routes that minimize adverse impacts on residential neighborhoods.

Per the Community Mobility Element of the Claremont General Plan (2009), Baseline Road is a designated truck route. Truck r outes are designated to ensure appropriate road construction and to protect residential neighborhoods (Claremont, 2009). With incorporation of mitigation measure TR-2, materials deliveri es and hauling for soil and de bris disposal related to the project would adhere to these truck routes.

As mitigated, the project would be consistent with the transportation policies detailed in the General Plan.

City of Claremont Draft Transportation St udy Guidelines for Vehicle Miles Traveled and Level of Service Assessment (2020). This document specifies impact assessment to be conducted for various types of development proj ects. Projects noted as potentially exempt include any proposed use that ca n demonstrate, based on the mo st current Trip Generation Manual, published by the Institute of Traffic Engineers (ITE), or other approved trip generation data, that there will be less than 50 vehicle trips during peak hours.

Once transported to the site, most construction equipment (b ackhoe, compactor, etc.) would remain in place for the durat ion of the construction peri od, and then be demobilized.

Construction necessary for implementation of the recharge project would temporarily increase vehicle miles traveled by:
 The approximately 10 construction workers that would travel to the project site for the 4-6 months of the construction period.
 Truck trips for materials deli veries, soil hauling, and c onstruction debris disposal.

Assuming 10 cubic yards per truck load, and a 4 to 6-month construction period, on the order of up to 1 to 3 truck trips would be required per day.

With an estimated maximum of 13 round trips per day (cons truction workers commuting to the site and haul trucks), traffic related to project construction would be substantially less than 50 peak hour trips.

As mitigated, traffic related to construction and operation of the project would not conflict with any goals of the relevant transportation plans for the project area. The project does not include new transportation systems. As mitigated by the implementation of TR-1, TR-2, and TR-3, impacts on transportation planning would be less than significant. b) Less than Significant Impact. CEQA Guidelines Section 15064.3 describes considerations for evaluating the transportation impacts of projects and states that vehicle miles traveled (the amount and distance of automobile travel attri butable to a project) is generally the most appropriate measure of transpor tation impacts. Since the proposed project is neither a land Section 2 – Environmental Analysis
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development project nor a transportation project that would permanently increase vehicle miles traveled in the project area, vehicle use for construction is considered. With an estimated maximum of 13 round trips per day (constructi on workers commuting to the site and haul trucks), traffic related to proj ect construction would be substantially less than 50 peak hour trips. Based on the estimated number of workers, material deliveries, so il hauling and debris removal hauling, project construc tion would have a less than significant impact on CEQA Guidelines Section 15064.3 subdivision (b).

Operation of the project would include annual maintenance that would last a few days to weeks and have limited and temporary impacts on transit systems. Periodic but infrequent hauling of sediment and debris would occur for basin ma intenance, and would a dd a limited number of dump trucks to area roadways. Project-relate d impacts on vehicle miles traveled during operations would be less than si gnificant. Additionally, the proposed project will remove the need to access the junction structure at the intersection of Baseline Road and Mills Avenue for operation of the slide gate, a beneficial impact.

Overall, construction and operation of the project would have a less than significant impact on vehicle miles traveled.
c) Less Than Significant Impact with Mitigation Incorporated. The project does not include any new roadway design features. However, traf fic control will be required for the following construction activities:
 Potholing of the 30-inch RCP storm drain adjacent to Mills Avenue  Removal of the concrete plug and existing slide gate from the junction structure in the intersection of Mills Avenue and Baseline Road
 Demolition of the existing 30-inch storm drain in the location of the proposed vault adjacent to Mills Avenue
 Construction and installation of the proposed transition structure, vault, and slide gate adjacent to Mills Avenue
At this time, it is anticipated that during construction to improve the storm drain system, one lane of traffic in Mills Avenue would be clos ed for a roadway length of approximately 60 to 100 feet, for approximately two weeks. Cons istent with mitigation measure TR-1, a Construction Traffic Management Plan would be prepared for the project and would reference City of Pomona Land Development General Notes:
 Adequate barricades, lights, flagmen, signs an d other safety devices shall be provided as specified by the traffic manual published by the state of Califo rnia Department of Transportation.

 Existing city streets shall be kept clean of all materials resulting from the grading operations. The street right-of-way shall be cleaned up daily, and as necessary, to maintain pedestrian and vehicular passage over the public right-of-way at all times.

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February 2023 Initial Study
Where construction would temporar ily block residential or busi ness driveways, coordination with the homeowners/owners would be conducted. Preparation of final traffic control plans for construction related work will be the responsib ility of the construction contractor. With implementation of mitigation measures TR-1, TR -2 and TR-3, the planned lane closures for storm drain improvements would have a less than significant impact on roadway hazards. d) Less Than Significant Impact with Mitigation Incorporated . Construction of the storm drain improvements would temporarily close one lane of traffic in Mills Avenue. Emergency vehicles would have restricted access on those roadways for the duration of the lane closures – estimated at approximately two weeks. Emer gency response providers (City of Claremont Police and Fire Departments) would be notified in advance of the construction schedule, location, and lane closures. With implementation of mitigation measure TR-1, the impact of lane closures and the approximately 13 additi onal construction-rela ted round trips per day would have a less than significant impact on emergency access.

Operation of the project would require the in frequent mobilization of heavy construction equipment to the PSG, at most once per month. No roadway closures or impacts to emergency access would occur.

Mitigation Measures
Implementation of the following mitigation m easures would reduce transportation impacts related to the proposed project to less than significant levels.

TR-1 Construction Traffic Management Plan. Prior to commencement of construction activities at a project site, the construction contractor shall develop and implement an approved Construction Traffic Manageme nt Plan addressing potential construction-related traffic detours and disruptions. In gene ral, the Construction Traffic Ma nagement Plan would ensure that to the extent practical, construction tr affic would access a project site during off-peak hours or limit access during the peak hours; and th at construction traffic would be routed to avoid travel through, or proximate to, sensitive land uses. The Pl an shall also include, where necessary, the use of flags, signs and lights, as well as flag persons to direct traffic.

TR-2 Heavy Equipment Travel . As part of the Constructi on Traffic Manage ment Plan, it shall be stipulated that the delivery and removal of heavy equipment shall be conducted during off-peak hours to minimize heavy truck activity during the morning and evening peak periods (7 am to 9 am and 4 pm to 6 pm) in order to have nominal impacts to traffic and circulation near the vicinity of the project.

TR-3 Haul Trucks. During site grading, where export of material is required, the construction contractor shall limit export activity between the hours of 7 am to 9 am (morning peak period) and 4 pm to 6 pm (evening peak period) to fe wer than the equivalent of 50 passenger car equivalent (PCE) truck trips per hour. 50 PCE tr uck trips equates to approximately 16 total trucks (8 trucks in and 8 trucks out) during the peak periods specified above in order to limit the potential impacts of haul truck activity during these busy commute times. [50 PCE truck trips / 3.0 PCE factor = 16 total trucks during the peak hour] Section 2 – Environmental Analysis
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2.3.18 Tribal Cultural Resources
Issues and Supporting Information Sources
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporated
Less Than
Significant
Impact
No
Impact
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) 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), or

b) 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.

Discussion: As described in Section 2.3.5, significan t cultural resources are not known or expected at the PSG or other project areas. However, mitigation measures have been identified in the event that previously unknown resources are identified during project construction (CR-3 and CR-4).

California Public Resources Code Secti ons 5097.94(a) and 5097.96 authorize the NAHC in Sacramento to maintain records of Native American sacred sites and burial sites in the Sacred Lands File as well as a Tribal Contact List of Native American who may wish to consult pursuant to AB52. On May 10, 2022, Stantec, on behalf of the City of Pomona, contacted the NAHC and requested a Sacred Lands file search for the entire study area. A response wa s received from the NAHC on June 10, 2022, indicating that the search ha d failed to identify any sacred lands and/or sacred sites.

On September 1, 2022, the City of Pomona sent AB52 notification letters via certified mail and follow-up emails to the 12 Native American contacts provided by the NAHC, to request information regarding lo cal knowledge about cultural resources, traditional gathering areas, or sacred lands in or near the project site. Input was received from the Y uhaaviatam of San Manuel Nation and the Gabrieleño Band of Mission Indians - Kizh Nation. The mitigation measures below reflect input provided by the Tribes. Copies of correspondence letters to the NAHC and Native American contacts are contained in Appendix C of the cultural repor t (on file with the City of Pomona).

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a) and b). Less than Significant with Mitigation Incorporated . Since archaeological resources are not known for the PSG or othe r project sites, proj ect construction and operation would not be anticipated to imp act Tribal Cultural Resources. However, mitigation measures CR-1 through CR-4 and TCR-1 through TCR-5 shall be implemented to further protect unknown cultural resources. As mitigated, the project would have a less than significant impact on California Register of Historic Resour ces (CRHR)-listed or eligible resources, or on resources significant to a California Native American tribe.

Mitigation Measures
Implementation of the following mitigation measures would reduce impacts on Tribal cultural resources to less than significant levels.

TCR-1 Tribal Notification. Tribal contacts identified by the NAHC (including the Yuhaaviatam of San Manuel Nation Cultural Resources Department (YSMN) and the Gabrieleño Band of Mission Indians – Kizh Nation) shall be contacted of any pre-contact and/or historic-era cultural resources discovered during project implementation, and be provided information regarding the nature of the find, so as to provide Tribal input with regards to significance and treatment. Should the find be deemed significant, as defined by CEQA (as amended, 2015), a Cultural Resources Monitoring and Treatment Plan shall be created by the qualified archaeologist, in coordination with relevant Tribes, and all subsequent finds shall be subject to this Plan. In the event of a significant find, the Plan shall allow for coordination of Native American monitoring by the YSMN and the Gabrieleño Band of Mission Indians – Kizh Nation.

TCR-2 Document Coordination. As requested, the City of Pomona shall provide archaeological/cultural documents created as a part of the project (isolate records, site records, survey reports, testing reports, etc.) to Tribes identified by the NAHC. The City of Pomona shall, in good faith, consult with interested Tribes identified by the NAHC throughout the life of the project.

TCR-3 Retain a Native American Monitor Prior to Commencement of Ground- Disturbing Activities
.

A. The City of Pomona shall retain a Native American Monitor from or approved by the Gabrieleño Band of Mission Indians – Kizh Nation. The monitor shall be retained prior to the commencement of any “ground-disturbing activity” for the subject project at all project locations (i.e., both on-site and any off-site locations that are included in the project description/definition and/or required in connection with the project, such as public improvement work). “Ground-disturbing activity” shall include, but is not limited to, demolition, pavement removal, potholing, auguring, grubbing, tree removal, boring, grading, excavation, drilling, and trenching.

B. A copy of the executed monitoring agreement shall be submitted to the City of Pomona prior to the earlier of the commencement of any ground-disturbing activity, or the issuance of any permit necessary to commence a ground-disturbing activity.

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C. The monitor will complete daily monitoring logs that will provide descriptions of the relevant ground-disturbing activities, the type of construction activities performed, locations of ground-disturbing activities, soil types, cultural-related materials, and any other facts, conditions, materials, or discoveries of significance to the Tribe. Monitor logs will identify and describe any discovered TCRs, including but not limited to, Native American cultural and historical artifacts, remains, places of significance, etc., (collectively, tribal cultural resources, or “TCR”), as well as any discovered Native American (ancestral) human remains and burial goods. Copies of monitor logs will be provided to the City of Pomona upon written request to the Tribe.

D. On-site tribal monitoring shall conclude upon the latter of the following (1) written confirmation to the Kizh from a designated point of contact for the City of Pomona that all ground-disturbing activities and phases that may involve ground-disturbing activities on the project site or in connection with the project are complete; or (2) a determination and written notification by the Kizh to the City of Pomona that no future, planned construction activity and/or development/construction phase at the project site possesses the potential to impact Kizh TCRs.

E. Upon discovery of any TCRs, all construction activities in the immediate vicinity of the discovery shall cease (i.e., not less than the surrounding 60 feet) and shall not resume until the discovered TCR has been fully assessed by the Kizh monitor and/or Kizh archaeologist.

The Kizh will recover and retain all discovered TCRs in the form and/or manner the Tribe deems appropriate, in the Tribe’s sole discretion, and for any purpose the Tribe deems appropriate, including for educational, cultural and/or historic purposes.

TCR-4 Unanticipated Discovery of Human Remains and Associated Funerary Objects.

A. Native American human remains are defined in PRC 5097.98 (d)(1) as an inhumation or cremation, and in any state of decomposition or skeletal completeness. Funerary objects, called associated grave goods in Public Resources Code Section 5097.98, are also to be treated according to this statute.

B. If Native American human remains and/or grave goods are discovered or recognized on the project site, then all construction activities shall immediately cease. Health and Safety Code Section 7050.5 dictates that any discoveries of human skeletal material shall be immediately reported to the County Coroner and all ground-disturbing activities shall immediately halt and shall remain halted until the coroner has determined the nature of the remains. If the coroner recognizes the human remains to be those of a Native American or has reason to believe they are Native American, he or she shall contact, by telephone within 24 hours, the Native American Heritage Commission, and Public Resources Code Section 5097.98 shall be followed.

C. Human remains and grave/burial goods shall be treated alike per California Public Resources Code section 5097.98(d)(1) and (2).

D. Construction activities may resume in other parts of the project site at a minimum of 200 feet away from discovered human remains and/or burial goods, if the Kizh determines in its Section 2 – Environmental Analysis

February 2023 Initial Study
sole discretion that resuming construction activities at that distance is acceptable and provides the project manager express consent of that determination (along with any other feasible mitigation measures the Kizh monitor and/or archaeologist deems necessary). (CEQA Guidelines Section 15064.5(f).)

E. Preservation in place (i.e., avoidance) is the preferred manner of treatment for discovered human remains and/or burial goods. Any historic archaeological material that is not Native American in origin (non-TCR) shall be curated at a public, non-profit institution with a research interest in the materials, such as the Natural History Museum of Los Angeles County or the Fowler Museum, if such an institution agrees to accept the material. If no institution accepts the archaeological material, it shall be offered to a local school or historical society in the area for educational purposes.

F. Any discovery of human remains/burial goods shall be kept confidential to prevent further disturbance.

TCR-5 Procedures for Burials and Funerary Remains.

A. As the Most Likely Descendant (“MLD”), the Koo-nas-gna Burial Policy shall be implemented. To the Tribe, the term “human remains” encompasses more than human bones.

In ancient as well as historic times, Tribal Traditions included, but were not limited to, the preparation of the soil for burial, the burial of funerary objects with the deceased, and the ceremonial burning of human remains.

B. If the discovery of human remains includes four or more burials, the discovery location shall be treated as a cemetery and a separate treatment plan shall be created.

C. The prepared soil and cremation soils are to be treated in the same manner as bone fragments that remain intact. Associated funerary objects are objects that, as part of the death rite or ceremony of a culture, are reasonably believed to have been placed with individual human remains either at the time of death or later; other items made exclusively for burial purposes or to contain human remains can also be considered as associated funerary objects.

Cremations will either be removed in bulk or by means as necessary to ensure complete recovery of all sacred materials.

D. In the case where discovered human remains cannot be fully documented and recovered on the same day, the remains will be covered with muslin cloth and a steel plate that can be moved by heavy equipment placed over the excavation opening to protect the remains. If this type of steel plate is not available, a 24-hour guard should be posted outside of working hours. The Tribe will make every effort to recommend diverting the project and keeping the remains in situ and protected. If the project cannot be diverted, it may be determined that burials will be removed.

E. In the event preservation in place is not possible despite good faith efforts by the City of Pomona, before ground-disturbing activities may resume on the project site, the City of Pomona shall arrange a designated site location within the footprint of the project property for the respectful reburial of the human remains and/or ceremonial objects.

Section 2 – Environmental Analysis
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Initial Study February 2023
F. Each occurrence of human remains and associated funerary objects will be stored using opaque cloth bags. All human remains, funerary objects, sacred objects and objects of cultural patrimony will be removed to a secure container on site if possible. These items should be retained and reburied within six months of recovery. The site of reburial/repatriation shall be on the project property but at a location agreed upon between the Tribe and the City of Pomona at a site to be protected in perpetuity. There shall be no publicity regarding any cultural materials recovered.

G. The Tribe will work closely with the project’s qualified archaeologist to ensure that the excavation is treated carefully, ethically, and respectfully. If data recovery is approved by the Tribe, documentation shall be prepared and shall include (at a minimum) detailed descriptive notes and sketches. All data recovery-related forms of documentation shall be approved in advance by the Tribe. If any data recovery is performed, once complete, a final report shall be submitted to the Tribe and the NAHC. The Tribe does NOT authorize any scientific study or the utilization of any invasive and/or destructive diagnostics on human remains.

Section 2 – Environmental Analysis

February 2023 Initial Study

2.3.19 Utilities and Service Systems
Issues and Supporting Information Sources
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporated
Less Than
Significant
Impact
No
Impact
Would the project:
a) Require or result in the relocation or construction of new or expanded water, wastewater treatment or storm water
drainage, electrical power, natural gas, or
telecommunications facilities, the construction or
relocation of which could cause significant environmental effects?

b) Have sufficient water supplies available to serve the project and reasonably foreseeable future development
during normal, dry and multiple dry years?

c) Result in a determination by the wastewater treatment provider which serves or may serve the project that it has adequate capacity to serve the project’s projected
demand in addition to the provider’s existing
commitments?

d) Generate solid waste in excess of State or local
standards, or in excess of the capacity of local
infrastructure, or otherwise impair the attainment of solid waste reduction goals?

e) Comply with federal, state, and local management and reduction statues and regulations related to solid waste?

Discussion: The proposed storm drain improvements would be installed in Mills Avenue. Existing utilities present near the junction structure and proposed vault include water mains, water laterals, sewer mains, sewer laterals, and communication lines.

a) Less than Significant Impact with Mitigation Incorporated. The objective of the project is to capture, treat and recharge storm water to im prove the reliability of the local potable water supply. As noted in this Initial Study, potentially significant project-related impacts have been mitigated to below levels of significance.

b) Less than Significant Impact. The project would increase the volume of water recharged to the Six Basins groundwater basins, a beneficial impact on water supplies. The project does not include residential, commercia l, or industrial development which would create additional water demand. Therefore, project-related imp acts on water supplies would be less than significant.

c) Less than Significant Impact . Habitable structures are not present on the project site and none are proposed as part of the project. The limited num ber of construction workers (approximately 10) required to implement the pr oject would not create the need for new or expanded wastewater service. Wastewater generated during cons truction by temporary workers and for basin operations would be treated locally in compliance with the requirements Section 2 – Environmental Analysis
Pedley Spreading Grounds Pond Enhancements Page 2-73
Initial Study February 2023
of the Los Angeles Regional Water Quality Control Board. The project would have a less than significant impact on wastewater treatment facilities.

d) and e) Less Than Significant Impact with Mitigation Incorporated. Construction of the proposed project is not anticipated to gene rate substantial excess soil requiring disposal – cut and fill will be balanced to the extent feasible. Construction debr is will result from installation of the storm drain improvements. The approximately 20 CY of asphalt debris would be transported to a CDI processing faci lity or permitted landfill. Project maintenance activities would result in addi tional debris requiring offsite disposal; annual volumes would vary based on the number, frequency, and seve rity of storms. With implementation of mitigation measure UTIL-1, anticipated wastes would be proce ssed and disposed at properly permitted local facilities and impacts related to solid waste disposal would be less than significant.

Mitigation Measure

The following mitigation measure would reduce project-related impacts on solid waste to less than significant levels.

UTIL-1 Implementation of a Construc tion and Demolition Disposal Plan. Prior to commencement of construction, the construction contractor shall prepare a Construction and Demolition (C&D) disposal plan for review and approval by the City of Claremont. Per California Green Building Standards C ode Section 45.408.1.1, Construction Waste Management Plan, the C&D Disposal Plan shall:
 Identify the construction and demolition waste materials to be divert ed from disposal by efficient usage, recycling, reuse on the project or salvage for future use or sale.  Determine if construction a nd demolition waste materials wi ll be sorted on-site (source- separated) or bulk mixed (single stream).
 Identify diversion facilities where construc tion and demolition wast e material collected will be taken.
 Specify that the amount of construction and de molition waste materials diverted shall be calculated by weight or volume, but not by both.

Section 2 – Environmental Analysis

February 2023 Initial Study

2.3.20 Wildfire
Issues and Supporting Information Sources
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporated
Less Than
Significant
Impact
No
Impact
If located in or near state responsibility areas or lands classified as very high fire hazard severity zones, would the project:
a) Substantially impair an adopted emergency
response plan or emergency evacuation plan?

b) Due to slope, prevailing winds, or other factors,
exacerbate wildfire risks, and thereby expose project
occupants to, pollutant concentrations from a wildfire
or the uncontrolled spread of a wildfire?

c) 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 ongoing impacts to the
environment?

d) 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?

Discussion: The wilderness areas in the northern part of Claremont (over 1 mile north of the PSG) are designated as within a very high fire hazard severity zone (CalFire, 2011). However, the project sites are not mapped within a fire hazard severity zone.

a) Less than Significant Impact. In the event of a disaster, specific evacuation routes in the City of Claremont are determined by the Claremont law enforcement agencies (Claremont, 2009).

Temporary lane closures duri ng storm drain improvements coul d impact the movement of emergency vehicles. To protect public safety, flag workers will be placed at intersections near lane closures to direct traffic. Local em ergency response agencies (Claremont Police Department and Claremont Fire Department) would be notifi ed of the timing and duration of planned lane closures. Since the project site is not designated as an emergency staging area, and since notifications to emergency providers would be conducted as part of the project, the project would have a less than significant impact on emergency access and evacuation plans.

b) Less than Significant Impact. Once installed, the proposed storm drain improvements would be buried and the road surface restored; there would be no impacts on wildfire hazards. As part of operations and maintenance, vegetation at PSG would be removed and managed. The on- going reduction in vegetation would have a beneficial impact on reducing fire risk at the site, as would the greater volumes of water present in the basins. New habitable structures are not proposed as part of the project and none are present on the project site. Therefore, the project would not expose project occupa nts to pollutant concentrati ons from a wildfire or the uncontrolled spread of wildfire. Overall, impac ts on wildfire risks would be less than significant. Since the PSG and locations for the storm drain improve ments are not mapped Section 2 – Environmental Analysis
Pedley Spreading Grounds Pond Enhancements Page 2-75
Initial Study February 2023
within a fire hazard severity zone, the Stra tegic Plan PEIR mitigat ion measures HAZ-5 and HAZ-6 would not be applicable to the proposed project.

c) Less Than Significant Impact. Construction for the proposed project includes installation of buried storm drain features, grad ing of existing recharge basi ns, and maintenance of project facilities. No new roads, fuel breaks, emergency water sources, power lines or utilities other than the storm drain improvements are proposed. Since the buried storm drain facilities would not increase fire risk and basin maintenance would manage vegetation thus reducing fuel for fires, the impact from new infrastructure on fire risk would be less than significant.

d) No Impact. Habitable structures are not present on the project sites and none are proposed as part of the project. Landslide and post-fire slope instability ar e not hazards identified for the project area, and the storm drain features for the project would be buried. Therefore, the project would not expose people or structures to significant wildfire risks.

Section 2 – Environmental Analysis

February 2023 Initial Study

2.3.21 Mandatory Findi ngs of Significance
Issues and Supporting Information Sources
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporated
Less Than
Significant
Impact
No
Impact
a) Does the project have t he potential to substantially degrade the quality of the environment, substantially
reduce the habitat of a fish or wildlife species, cause a fish or wildlife population to drop below self-sustaining levels, threaten to eliminate a plant or animal community, substantially reduce the number or restrict the range of a rare or endangered plant or animal, or eliminate
important examples of the major periods of California
history or prehistory?

b) Does the project have t he potential to achieve short- term, to the disadvantage of long-term, environmental
goals?

c) Does the project have im pacts that are individually limited, but cumulatively considerable (“cumulatively
considerable” means that the incremental effects of a
project are considerable when viewed in connection with the effects of past projects, effects of other current
projects, and the effects of probable future projects.)?

d) Does the project have environmental effects which will cause substantial adverse effects on human beings,
either directly or indirectly?

Discussion:
a) Less than Significant Impact with Mitigation Incorporated. Most of the sensitive plants and wildlife known from the region have low or no potential to occur on the project site due to the low quality and small size the vegetation communities on the site, and the lack of surrounding native vegetation. A preconstructi on survey for sensitive species will be conducted prior to the start of construction a nd mitigation shall be implemented to avoid significant impacts if a sensitive species occu rs on the project site. If project construction occurs during the avian nesting season, mitigati on will be implemented to avoid significant impacts to protected nesting bird species. Additional mitigation will be implemented to reduce impacts to riparian habitat (mulefat thickets). As mitigated, the construction and operation of the proposed project would not substantially degrade biological resources and impacts would be less than significant.

Cultural resources are not known for the project sites and mitig ation measures have been identified to protect resources in the unlikel y event they are discove red during construction.

Therefore, the project would not eliminate important exampl es of the major periods of California history or prehistory.

b) and c) Less than Significant Impact. The proposed project is one element of the Six Basins Strategic Plan. The Strategic Plan would improve management of the Six Basins groundwater basins by implementation of improvements to existing facilities as well as development of new facilities. Cumulatively, the projects included in the Strategic Plan would increase recharge Section 2 – Environmental Analysis
Pedley Spreading Grounds Pond Enhancements Page 2-77
Initial Study February 2023
and storage, and improve water quality. Achievement of the Strategic Plan goals would result in the long-term sustainability of the local water supply for residential, commercial, and industrial water users into th e future. Overall, the propose d project would increase the reliability of groundwater resources in the Pomona service area, a beneficial long-term goal.

d) Less than Significant Impact with Mitigation Incorporated. Implementation of the project would improve the management of stormwat er runoff and supplemen t local groundwater resources. The project would increase the sustainability of the local water supply and improve water quality, beneficial impacts on human be ings. Temporary impacts on human beings during construction (e.g., air pollutant emissions, traffic, and noise) would be mitigated to less than significant levels.

Pedley Spreading Grounds Pond Enhancements Page 3-1
Initial Study February 2023
Section 3
References, Abbreviations, and
Report Preparation

3.1 REFERENCES AND BIBLIOGRAPHY
American Society of Civil Engineers. 2017. Minimum Design Loads and Associated Criteria for Buildings and Other Structures (7-16). 800 pp. 2 volume set.

California Air Resources Board (CARB). 2019. 2019 Edition, California Greenhouse Gas Emission Inventory: 2000 – 2017. Available:
https://ww3.arb.ca.gov/cc/inventory/pubs/reports/2000_2017/ghg_inventory_trends_00-17.pdf

-----. 2017. California’s 2017 Climate Change Scoping Plan: The Strategy for Achieving California’s 2030 GHG target. Adopted November 2017. Available:
https://ww3.arb.ca.gov/cc/scopingplan/scoping_plan_2017.pdf -----. 2008. Climate Change Scoping Plan. Adopted December 12, 2008.

California Department of Conservation. 2022. Division of Land Resource Protection Farmland Mapping and Monitoring Program. California Important Farmland Finder. Available:
https://maps.conservation.ca.gov/DLRP/CIFF/

-----. 2015. California Geological Survey. California Geologic Map of California. Available:
https://maps.conservation.ca.gov/cgs/gmc/

California Department of Fi sh and Wildlife (CDFW). 20 22a. RAREFIND database ed.3.1.1.

Electronic database managed by th e California Natural Diversity Data Base, Wildlife Data and Habitat Analysis Branch, Califor nia Department of Fi sh and Wildlife. Sacramento, California.

CNDDB Maps and Data (ca.gov). Accessed July 2022.

-----. 2022b. State and Federally Listed Endangered and Threatened Plants of California. State and Federally Listed Endangered, Threatened, and Rare Plants of California. Accessed July 2022.
-----. 2022c. Special Animals List. CNDDB_Special_Animals_List (3).pdf. Accessed July 2022.

-----. 2022d. California’s Wildlife – Life History and Range. Available online:
https://wildlife.ca.gov/Data/CWHR/Life-History-and-Range. Accessed July 2022.

-----. 2022e. California Sensitive Natural Communities. https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=153609&inline. Accessed July 2022.

Section 3 – References, Abbreviations, and Report Preparation

February 2023 Initial Study
California Department of Forestry and Fire Protection (CalFire). 2011. Very High Fire Hazards Severity Zones in LRA. Claremont Map. Available:
https://osfm.fire.ca.gov/media/5811/claremont.pdf

California Department of Toxic Substances Control (DTSC). 2022. Envirostor. Available:
https://www.envirostor.dtsc.ca.gov/public/.

California Department of Transportation. 2018. California State Scenic Highway System Map.

Available:
https://caltrans.maps.arcgis.com/apps/webappviewer/index.html?id=465dfd3d807c46cc8e80571 16f1aacaa

California Environmental Protection Agency (CalEPA). 2022. Cortese List Data Sources. Available:
https://calepa.ca.gov/sitecleanup/corteselist/

California Native Plant Society (CNPS). 2022. Inventory of ra re and endangered plants. http://www.rareplants.cnps.org/. Accessed July 2022.

California Regional Water Quality Control Board, Los Angeles Region (RWQCB). 2014.

Water Quality Control Plan: Los Angeles Region Basin Plan for the Coastal Watersheds of Los Angeles and Ventura Counties. Amended through 2020. Available:
https://www.waterboards.ca.gov/losangeles/water_issues/programs/basin_plan/basin_plan_docu mentation.html

California, State of. 1998. Superior Court of California for the County of Los Angeles (Case No.

KC029152) Stipulated Judgement. Southern Californi a Water Company vs. City of La Verne, et al.

California State Water Resources Control Board (SWRCB). 2022. GeoTracker. Available:
http://geotracker.waterboards.ca.gov/.

-----. 2021. State Policy for Water Quality Control: State Wetland Definition and Procedures for Discharges of Dredged or Fill Material to Waters of the State. April 6.

Claremont, City of. 2020. City of Claremont Draft Transportation Study Guidelines for Vehicle Miles Traveled and Level of Service Assessment. August. Available:
https://www.ci.claremont.ca.us/home/showpublisheddocument/15846/637468392143100000

-----. 2014a. Land Use Plan Claremont General Plan. February 11. Available:
https://www.ci.claremont.ca.us/home/showpublisheddocument/1524/635883852763000000

-----. 2014b. City of Claremont Zoning Map. February 25. Available:
https://www.ci.claremont.ca.us/home/showpublisheddocument/1526/635883852966700000

Section 3 – References, Abbreviations, and Report Preparation Pedley Spreading Grounds Pond Enhancements Page 3-3
Initial Study February 2023
-----. 2009. General Plan. Adopted November 14, 2006. Revised October 13, 2009. CC Resolution #2009-72. Available: https://www.ci.claremont.ca.us/government/departments- divisions/planning-division/general-plan

Converse Consultants. 2022. Geotechnical Investigation Report. Pedley Spreading Grounds Pond Enhancements. Prepared for Stantec Consulting Services Inc. June 6. Project No. 21-31- 201-01.

Critelli, S. P. Rumelhart, and R. Ingersoll. 1995. Petrofacies and provenance of the Puente Formation (middle to upper Miocene), Los Angeles Basin, southern California: implications for rapid uplift and accumulation rates. Journal of Sedimentary Research A65: 656-667.

Harden, D. 2004. California Geology, 2nd edition. Pearson Prentice Hall, 552 p.

Ingersoll, R. V. and P. E. Rumelhart. 1999. Three-stage basin evolution of the Los Angeles basin, southern California. Geology 27: 593-596.

International Conference of Building Official (ICBO). 1994. Uniform Building Code.

Murphey, P., G. Knauss, L. Fisk, T. Demere, and R. Reynolds. 2019. Best practices in mitigation paleontology. Proceedings of the San Diego Society of Natural History 47: 43 pp.

Norris, Robert M. and Robert W. Webb. 1990. Geology of California. John Wiley & Sons Inc.

Pomona, City of. 2022. Preliminary Design Report. Pedley Spreading Grounds – Pond Enhancements. Prepared by Stantec Consulting Services Inc. Project Number: 184031542.

-----. 2011. Integrated Water Supply Plan. Available:
https://www.pomonaca.gov/home/showpublisheddocument/544/637457871401200000

Sawyer, J.O., T. Keeler-Wolf and J.M. Evens. 2009. Manual of California Vegetation, Second Edition. California Native Plant Society, Sacramento, California.

Six Basins Watermaster. 2020. Reconnaissance-Level Recharge Study in the Six Basins.

Prepared by Stantec and West Yost Associates. Final February 2020. Available:
https://westyost-
my.sharepoint.com/personal/aponcelet_westyost_com/_layouts/15/onedrive.aspx?id=%2Fperson al%2Faponcelet%5Fwestyost%5Fcom%2FDocuments%2F6BWM%20Documents%2F2020021 8%5FRecharge%20Basin%20Study%5Freport%2Epdf&parent=%2Fpersonal%2Faponcelet%5F westyost%5Fcom%2FDocuments%2F6BWM%20Documents&ga=1

Society of Vertebrate Paleontology (SVP). 2010. Standard Procedures for the assessment and Mitigation of adverse impacts to paleontological resources. Available: https://vertpaleo.org/wp- content/uploads/2021/01/SVP_Impact_Mitigation_Guidelines.pdf; Accessed on November 9, 2022.

Section 3 – References, Abbreviations, and Report Preparation

February 2023 Initial Study
Society of Vertebrate Paleontology (SVP) Conformable Impact Mitigation Guidelines Committee. 1996. Conditions of Receivership for Paleontologic Salvage Collections. Society of Vertebrate Paleontology News Bulletin, Vol. 166, pp. 31-32.

-----. 1995. Assessment and Mitigation of Adverse Impacts to Nonrenewable Paleontologic Resources – Standard Guidelines. Society of Vertebrate Paleontology News Bulletin, Vol. 163, pp. 22-27.

South Coast Air Quality Management District (SCAQMD). 2022. Air Quality Management Plan (AQMP). Available: http://www.aqmd.gov/home/air-quality/clean-air-plans/air-quality-mgt-plan

-----. 2018. National Ambient Air Quality Standards (NAAQS) and California Ambient Air Quality Standards (CAAQS) Attainment Status for South Coast Air Basin). Available:
https://www.aqmd.gov/docs/default-source/clean-air-plans/air-quality-management-plans/naaqs- caaqs-feb2016.pdf?sfvrsn=14

-----. 2016. Air Quality Management Plan. Available: http://www.aqmd.gov/home/air- quality/clean-air-plans/air-quality-mgt-plan/final-2016- aqmp#:~:text=The%202016%20AQMP%20includes%20the%20integrated%20strategies%20and ,as%20the%20latest%2024-hr%20and%20annual%20PM2.5%20standards.

Southern California Association of Governments (SCAG). 2016. The 2016-2040 Regional Transportation Plan / Sustainable Communities Strategy. April. Available:
https://scag.ca.gov/sites/main/files/file-attachments/f2016rtpscs.pdf?1606005557

Three Valley Municipal Water District (TVMWD). 2021. Six Basins Strategic Plan Draft Program Environmental Impact Report. Available:
https://www.threevalleys.com/uploads/files/Projects/Six%20Basins%20Strategic%20Plan/Six%2 0Basins%20Draft%20PEIR%20-%20Volume%201.pdf

United States Department of the Interior Bureau of Reclamation. 2013. Technical Memorandum No. 2 Greenhouse Gas Emissions Calculator for the Water Sector. August.

Available:
https://usbr.gov/lc/socal/basinstudies/OWOWReferences/FinalReport/TM%202%20GHGE%20 Calculator.pdf

United States Department of Transportation Federal Highway Administration (FHA). 2017.

Construction Noise Handbook. August 24, 2017. Available:
https://www.fhwa.dot.gov/environment/noise/construction_noise/handbook/handbook09.cfm

United States Department of Transportation Federal Transit Administration (FTA). 2006.

Transit Noise and Vibration Impact Assessment. FTA-VA-90-1003-06. May 2006. Authors:

Carl E. Hanson, David A. Towers, and Lance D. Meister. Available:
https://www.transit.dot.gov/sites/fta.dot.gov/files/docs/FTA_Noise_and_Vibration_Manual.pdf

Section 3 – References, Abbreviations, and Report Preparation Pedley Spreading Grounds Pond Enhancements Page 3-5
Initial Study February 2023
United States Fish and Wildlife Service (USFWS). 2022a. Environmental Conservation Online System. Critical Habitat for Threatened & Endangered Species. Available online:
https://fws.maps.arcgis.com/home/webmap/viewer.html?webmap=9d8de5e265ad4fe09893cf75b 8dbfb77. Accessed July 2022.

-----. 2022b. Information for Planning and Consultation. Online: https://ecos.fws.gov/ipac/.

Accessed July 2022.

USNVC (U. S. National Vegetation Classification) Database 2.04. 2022. Federal Geographic Data Committee, Vegetation Subcommittee. Washington D.C. The U.S. National Vegetation Classification – Your guide to the nations vegetation (usnvc.org). Accessed July 2022.

Upland, City of. 2015. Cable Airport Land Use Compatibility Plan. Adopted by Upland City Council September 14, 2015. Available:
https://www.uplandca.gov/uploads/ftp/city_departments/development_services/planning/cable_a irport_land_use_comp_plan/pdfs/CCB.Front%20Body.2015-11-09.pdf

Yerkes, R. F., T. H. McCulloh, J. E. Schollhamer, and J. G. Vedder. 1965. Geology of the Los Angeles Basin – an introduction. United States Geological Survey Professional Paper 420-A.

Section 3 – References, Abbreviations, and Report Preparation

February 2023 Initial Study

3.2 ACRONYMS AND ABBREVIATIONS

AAQS
AB
Ambient air quality standards
Assembly Bill
ac
ac-ft
acre
acre-feet
af
afd
afy
acre-feet
acre-feet per day
acre-feet per year
amsl above mean sea level
AQMP Air Quality Management Plan
ASCE American Society of Civil Engineers
BACM
BERD
BMP
Best available control measure
Built Environment Resource Directory
best management practice
BRTR Biological Resources Technical Report
BSA Biological Study Area
CalEEMod
CalEPA
California Emissions Estimator Model
California Environmental Protection Agency
Caltrans California Department of Transportation
CARB California Air Resources Board
C&D
CDFW
CDI
Construction and demolition
California Department of Fish and Wildlife
Construction, Demolition, and Inert Debris
CEQA California Environmental Quality Act
CH
4 CNEL
CNPS
Methane
Community Noise Equivalent Level
California Native Plant Society
CO
CO
2 carbon monoxide
carbon dioxide
CO2e
Cr-6
carbon dioxide equivalent
hexavalent chromium
Section 3 – References, Abbreviations, and Report Preparation Pedley Spreading Grounds Pond Enhancements Page 3-7
Initial Study February 2023
CRHR
CY
dBA
California Register of Historic Resources
cubic yards
A-weighted decibels
DCE
DPM
DTSC
1,1-dichloroethene
diesel particulate matter
Department of Toxic Substances Control
EIR Environmental Impact Report

ESGVWMG
Farmland
FE
East San Gabriel Valley Watershed Management Group
Prime Farmland, Unique Farmland, or Farmland of Statewide Importance Federally Endangered
FEMA
FHA
Federal Emergency Management Agency
Federal Highway Administration
FMMP Farmland Mapping and Monitoring Program
FTA
GHG
Federal Transit Administration
greenhouse gas
HDPE high-density polyethylene
HRA
ICBO
in/hr
IS
ITE
lbs
Health Risk Assessment
International Conference of Building Officials
inches per hour
Initial Study
Institute of Traffic Engineers
pounds
Lmax maximum sound level during a measurement period or a noise event LST
LUST
Local Significance Thresholds
Leaking Underground Storage Tank
Ma
MBTA
mgd
MLD
Million years ago
Migratory Bird Treaty Act
million gallons per day
Most Likely Descendant
MMT
MPA
MRZ-2
million metric tons
microscopic particulate analysis
Mineral Zone 2
Section 3 – References, Abbreviations, and Report Preparation

February 2023 Initial Study
MS4
N2O
NAHC
Municipal Separate Storm Sewer System
nitrous oxide
Native American Heritage Commission
NOI
NPDES
NOx
Notice of Intent
National Pollutant Discharge Elimination System
Nitrogen oxide
O
3 O&M
ozone
Operations and Maintenance
Pb
PCC
lead
Portland Cement Concrete
PCE
PCE
PDR
PEIR
PFP
PM
PM

2.5 Passenger car equivalent
tetrachloroethene
Preliminary Design Report
Program Environmental Impact Report
Pedley Filtration Plant
particulate matter
particulate matter 2.5 microns or less in diameter
PM
10 PMMP
PPV
P/RC
PSG
RCP

RTP/SCS
RWQCB
particulate matter 10 microns or less in diameter
Paleontological Monitoring and Mitigation Plan
peak particle velocity
Park/Resource Conservation
Pedley Spreading Grounds
Reinforced Concrete Pipe
Regional Transportation Plan/Sustainable Communities Strategies Regional Water Quality Control Board
SCAB
SCAG
SCAQMD
South Coast Air Basin
Southern California Associations of Governments
South Coast Air Quality Management District
SCCIC
SE
SGMA

SGVMVCD
South Central Coastal Information Center
State Endangered
Sustainable Groundwater Management Act
San Gabriel Valley Mosquito and Vector Control District Section 3 – References, Abbreviations, and Report Preparation Pedley Spreading Grounds Pond Enhancements Page 3-9
Initial Study February 2023
SLF Sacred Lands File
SMARA
SO2
Surface Mining and Reclamation Act
sulfur dioxide
SR State Route
SRA
SSC
Stantec
SVP
SWPPP
site receptor area
species of special concern
Stantec Consulting Services Inc.

Society of Vertebrate Paleontology
Stormwater Pollution Prevention Plan
SWRCB
TAC
TCE
TCP
TCR
TDS
TVMWD
UCMP
State Water Resources Control Board
Toxic air contaminant
trichloroethene
trichloropropane
Tribal Cultural Resources
total dissolved solids
Three Valleys Municipal Water District
University of California Museum of Paleontology
USACE
USEPA
United States Army Corps of Engineers
United States Environmental Protection Agency
USFWS United States Fish and Wildlife Service
USGS
USNVC
United States Geological Survey
United States National Vegetation Classification
VOC
WDID
WDR
WMP
YSMN
Volatile Organic Compound
Waste Discharge Identification
Waste Discharge Requirements
Watershed Management Plan
Yuhaaviatam of San Manuel Nation

Section 3 – References, Abbreviations, and Report Preparation

February 2023 Initial Study

3.3 PREPARERS OF THE INITIAL STUDY
City of Pomona
Jorge D. Anaya, Senior Water Resources Engineer

TECHNICAL ASSISTANCE PROVIDED BY:

Stantec Consulting Services Inc.

Jon Abelson, PE, PMP, ENV SP, Project Manager
Alexis Holmdal, PE, PMP, ENV SP, Project Engineer
Sarah Garber, PMP, CPP, Environmental Lead
Jared Varonin, Biological Resources Manager
Ashleigh Townsend, Biologist
Melissa Tu, Biologist
Shannon Loftus, RPA, Cultural Resources Manager
Colleen Hulbert, Archaeologist
Kaitlyn Heck, Air Quality
Danny Law, GIS
CEQA Initial Study

Appendix A

Air Quality Modeling Output

Pedley Spreading Grounds Pond Enhancements

CALEEMOD OUTPUT FILES - CONSTRUCTION
Pedley Spreading Basins
South Coast Air Basin, Annual
Project Characteristics -
Land Use - Size of basins, spreading area, and maximum area of pipeline to be improved; 2 ksf concrete emergency spillway Construction Phase -
Off-road Equipment -
Trips and VMT -
On-road Fugitive Dust -
Grading - 12,316 CY of Cut and 12,045 of fill - 271 CY hauled off site; 128 CY of slope armor imported Construction Off-road Equipment Mitigation -
Fleet Mix -

1.1 Land Usage
Land Uses
Size
Metric
Lot Acreage
Floor Surface Area
Population
Other Asphalt Surfaces

2.00 1000sqft

0.05 2,000.00
0 Other Non-Asphalt Surfaces

20.40 Acre

20.40 888,624.00
0 1.2 Other Project Characteristics
Urbanization
Climate Zone
Urban
9 Wind Speed (m/s)
Precipitation Freq (Days)

2.2 31

1.3 User Entered Comments & Non-Default Data

1.0 Project Characteristics
Utility Company
Southern California Edison
2024
Operational Year
CO2 Intensity
(lb/MWhr)
390.98

0.033
CH4 Intensity
(lb/MWhr)

0.004
N2O Intensity
(lb/MWhr)
CalEEMod Version: CalEEMod.2020.4.0
Date: 11/8/2022 11:58 AM

Pedley Spreading Basins - South Coast Air Basin, Annual EMFAC Off-Model Adjustment Factors for Gasoline Light Duty Vehicle to Account for the SAFE Vehicle Rule Not Applied

2.0 Emissions Summary
Table Name
Column Name
Default Value
New Value
tblAreaCoating
Area_Parking
53437
52272
tblConstDustMitigation
WaterUnpavedRoadVehicleSpeed
0 15
tblGrading
MaterialExported

0.00 271.00
tblGrading
MaterialImported

0.00 128.00
CalEEMod Version: CalEEMod.2020.4.0
Date: 11/8/2022 11:58 AM

Pedley Spreading Basins - South Coast Air Basin, Annual EMFAC Off-Model Adjustment Factors for Gasoline Light Duty Vehicle to Account for the SAFE Vehicle Rule Not Applied

2.1 Overall Construction
ROG
NOx
CO
SO2
Fugitive
PM10
Exhaust
PM10
PM10
Total
Fugitive
PM2.5
Exhaust
PM2.5
PM2.5
Total
Bio- CO2
NBio- CO2
Total CO2
CH4
N2O
CO2e
Year
tons/yr
MT/yr
2023

0.1429

1.4531

1.2504

2.6900e-
003

0.4312

0.0614

0.4926

0.1813

0.0565

0.2377

0.0000
237.1351
237.1351

0.0739

4.4000e-
004
239.1131
Maximum

0.1429

1.4531

1.2504

2.6900e-
003

0.4312

0.0614

0.4926

0.1813

0.0565

0.2377

0.0000
237.1351
237.1351

0.0739

4.4000e-
004
239.1131
Unmitigated Construction
ROG
NOx
CO
SO2
Fugitive
PM10
Exhaust
PM10
PM10
Total
Fugitive
PM2.5
Exhaust
PM2.5
PM2.5
Total
Bio- CO2
NBio- CO2
Total CO2
CH4
N2O
CO2e
Year
tons/yr
MT/yr
2023

0.1429

1.4531

1.2504

2.6900e-
003

0.1999

0.0614

0.2613

0.0831

0.0565

0.1396

0.0000
237.1349
237.1349

0.0739

4.4000e-
004
239.1128
Maximum

0.1429

1.4531

1.2504

2.6900e-
003

0.1999

0.0614

0.2613

0.0831

0.0565

0.1396

0.0000
237.1349
237.1349

0.0739

4.4000e-
004
239.1128
Mitigated Construction
ROG
NOx
CO
SO2
Fugitive
PM10
Exhaust
PM10
PM10
Total
Fugitive
PM2.5
Exhaust
PM2.5
PM2.5
Total
Bio- CO2
NBio-CO2
Total CO2
CH4
N20
CO2e
Percent
Reduction

0.00 0.00

0.00 0.00

53.63 0.00

46.95 54.13

0.00 41.28

0.00 0.00

0.00 0.00

0.00 0.00
CalEEMod Version: CalEEMod.2020.4.0
Date: 11/8/2022 11:58 AM

Pedley Spreading Basins - South Coast Air Basin, Annual EMFAC Off-Model Adjustment Factors for Gasoline Light Duty Vehicle to Account for the SAFE Vehicle Rule Not Applied

Quarter
Start Date
End Date
Maximum Unmitigated ROG + NOX (tons/quarter)
Maximum Mitigated ROG + NOX (tons/quarter)
1 1-2-2023
4-1-2023

1.1903

1.1903
2 4-2-2023
7-1-2023

0.3841

0.3841
Highest

1.1903

1.1903

2.2 Overall Operational
ROG
NOx
CO
SO2
Fugitive
PM10
Exhaust
PM10
PM10
Total
Fugitive
PM2.5
Exhaust
PM2.5
PM2.5
Total
Bio- CO2
NBio- CO2
Total CO2
CH4
N2O
CO2e
Category
tons/yr
MT/yr
Area

0.0697

0.0000

2.9000e-
004

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

5.6000e-
004

5.6000e-
004

0.0000

0.0000

5.9000e-
004
Energy

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Mobile

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Waste

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Water

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Total

0.0697

0.0000

2.9000e-
004

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

5.6000e-
004

5.6000e-
004

0.0000

0.0000

5.9000e-
004
Unmitigated Operational
CalEEMod Version: CalEEMod.2020.4.0
Date: 11/8/2022 11:58 AM

Pedley Spreading Basins - South Coast Air Basin, Annual EMFAC Off-Model Adjustment Factors for Gasoline Light Duty Vehicle to Account for the SAFE Vehicle Rule Not Applied

2.2 Overall Operational
ROG
NOx
CO
SO2
Fugitive
PM10
Exhaust
PM10
PM10
Total
Fugitive
PM2.5
Exhaust
PM2.5
PM2.5
Total
Bio- CO2
NBio- CO2
Total CO2
CH4
N2O
CO2e
Category
tons/yr
MT/yr
Area

0.0697

0.0000

2.9000e-
004

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

5.6000e-
004

5.6000e-
004

0.0000

0.0000

5.9000e-
004
Energy

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Mobile

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Waste

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Water

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Total

0.0697

0.0000

2.9000e-
004

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

5.6000e-
004

5.6000e-
004

0.0000

0.0000

5.9000e-
004
Mitigated Operational

3.0 Construction Detail
Construction Phase
Phase
Number
Phase Name
Phase Type
Start Date
End Date
Num Days
Week
Num Days
Phase Description
1 Site Preparation
Site Preparation
1/2/2023
1/13/2023
5 10
2 Grading
Grading
1/14/2023
3/3/2023
5 35
3 Utilities
Grading
3/4/2023
4/21/2023
5 35
ROG
NOx
CO
SO2
Fugitive
PM10
Exhaust
PM10
PM10
Total
Fugitive
PM2.5
Exhaust
PM2.5
PM2.5
Total
Bio- CO2
NBio-CO2
Total CO2
CH4
N20
CO2e
Percent
Reduction

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00
CalEEMod Version: CalEEMod.2020.4.0
Date: 11/8/2022 11:58 AM

Pedley Spreading Basins - South Coast Air Basin, Annual EMFAC Off-Model Adjustment Factors for Gasoline Light Duty Vehicle to Account for the SAFE Vehicle Rule Not Applied

4 Paving
Paving
4/22/2023
5/19/2023
5 20
OffRoad Equipment
Phase Name
Offroad Equipment Type
Amount
Usage Hours
Horse Power
Load Factor
Site Preparation
Rubber Tired Dozers
3 8.00
247

0.40 Site Preparation
Tractors/Loaders/Backhoes
4 8.00
97 0.37
Grading
Excavators
2 8.00
158

0.38 Grading
Graders
1 8.00
187

0.41 Grading
Rubber Tired Dozers
1 8.00
247

0.40 Grading
Scrapers
2 8.00
367

0.48 Grading
Tractors/Loaders/Backhoes
2 8.00
97 0.37
Utilities
Excavators
2 8.00
158

0.38 Utilities
Graders
1 8.00
187

0.41 Utilities
Rubber Tired Dozers
1 8.00
247

0.40 Utilities
Scrapers
2 8.00
367

0.48 Utilities
Tractors/Loaders/Backhoes
2 8.00
97 0.37
Paving
Pavers
2 8.00
130

0.42 Paving
Paving Equipment
2 8.00
132

0.36 Paving
Rollers
2 8.00
80 0.38
Trips and VMT
Residential Indoor: 0; Residential Outdoor: 0; Non-Residential Indoor: 0; Non-Residential Outdoor: 0; Striped Parking Area: 0 (Architectural Coating
–
sqft)
Acres of Grading (Site Preparation Phase): 15
Acres of Grading (Grading Phase): 105
Acres of Paving: 20.45
CalEEMod Version: CalEEMod.2020.4.0
Date: 11/8/2022 11:58 AM

Pedley Spreading Basins - South Coast Air Basin, Annual EMFAC Off-Model Adjustment Factors for Gasoline Light Duty Vehicle to Account for the SAFE Vehicle Rule Not Applied

3.2 Site Preparation - 2023
ROG
NOx
CO
SO2
Fugitive
PM10
Exhaust
PM10
PM10
Total
Fugitive
PM2.5
Exhaust
PM2.5
PM2.5
Total
Bio- CO2
NBio- CO2
Total CO2
CH4
N2O
CO2e
Category
tons/yr
MT/yr
Fugitive Dust

0.0983

0.0000

0.0983

0.0505

0.0000

0.0505

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Off-Road

0.0133

0.1376

0.0912

1.9000e-
004

6.3300e-
003

6.3300e-
003

5.8200e-
003

5.8200e-
003

0.0000

16.7254

16.7254

5.4100e-
003

0.0000

16.8606
Total

0.0133

0.1376

0.0912

1.9000e-
004

0.0983

6.3300e-
003

0.1046

0.0505

5.8200e-
003

0.0563

0.0000

16.7254

16.7254

5.4100e-
003

0.0000

16.8606
Unmitigated Construction On-Site

3.1 Mitigation Measures Construction
Water Exposed Area
Reduce Vehicle Speed on Unpaved Roads
Phase Name
Offroad Equipment
Count
Worker Trip
Number
Vendor Trip
Number
Hauling Trip
Number
Worker Trip
Length
Vendor Trip
Length
Hauling Trip
Length
Worker Vehicle
Class
Vendor
Vehicle Class
Hauling
Vehicle Class
Site Preparation
7 18.00

0.00 0.00

14.70 6.90

20.00 LD_Mix
HDT_Mix
HHDT
Grading
8 20.00

0.00 50.00

14.70 6.90

20.00 LD_Mix
HDT_Mix
HHDT
Utilities
8 20.00

0.00 0.00

14.70 6.90

20.00 LD_Mix
HDT_Mix
HHDT
Paving
6 15.00

0.00 0.00

14.70 6.90

20.00 LD_Mix
HDT_Mix
HHDT
CalEEMod Version: CalEEMod.2020.4.0
Date: 11/8/2022 11:58 AM

Pedley Spreading Basins - South Coast Air Basin, Annual EMFAC Off-Model Adjustment Factors for Gasoline Light Duty Vehicle to Account for the SAFE Vehicle Rule Not Applied

3.2 Site Preparation - 2023
ROG
NOx
CO
SO2
Fugitive
PM10
Exhaust
PM10
PM10
Total
Fugitive
PM2.5
Exhaust
PM2.5
PM2.5
Total
Bio- CO2
NBio- CO2
Total CO2
CH4
N2O
CO2e
Category
tons/yr
MT/yr
Hauling

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Vendor

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Worker

2.8000e-
004

2.2000e-
004

2.9300e-
003

1.0000e-
005

9.9000e-
004

1.0000e-
005

9.9000e-
004

2.6000e-
004

1.0000e-
005

2.7000e-
004

0.0000

0.7727

0.7727

2.0000e-
005

2.0000e-
005

0.7791
Total

2.8000e-
004

2.2000e-
004

2.9300e-
003

1.0000e-
005

9.9000e-
004

1.0000e-
005

9.9000e-
004

2.6000e-
004

1.0000e-
005

2.7000e-
004

0.0000

0.7727

0.7727

2.0000e-
005

2.0000e-
005

0.7791
Unmitigated Construction Off-Site
ROG
NOx
CO
SO2
Fugitive
PM10
Exhaust
PM10
PM10
Total
Fugitive
PM2.5
Exhaust
PM2.5
PM2.5
Total
Bio- CO2
NBio- CO2
Total CO2
CH4
N2O
CO2e
Category
tons/yr
MT/yr
Fugitive Dust

0.0442

0.0000

0.0442

0.0227

0.0000

0.0227

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Off-Road

0.0133

0.1376

0.0912

1.9000e-
004

6.3300e-
003

6.3300e-
003

5.8200e-
003

5.8200e-
003

0.0000

16.7253

16.7253

5.4100e-
003

0.0000

16.8606
Total

0.0133

0.1376

0.0912

1.9000e-
004

0.0442

6.3300e-
003

0.0506

0.0227

5.8200e-
003

0.0286

0.0000

16.7253

16.7253

5.4100e-
003

0.0000

16.8606
Mitigated Construction On-Site
CalEEMod Version: CalEEMod.2020.4.0
Date: 11/8/2022 11:58 AM

Pedley Spreading Basins - South Coast Air Basin, Annual EMFAC Off-Model Adjustment Factors for Gasoline Light Duty Vehicle to Account for the SAFE Vehicle Rule Not Applied

3.2 Site Preparation - 2023
ROG
NOx
CO
SO2
Fugitive
PM10
Exhaust
PM10
PM10
Total
Fugitive
PM2.5
Exhaust
PM2.5
PM2.5
Total
Bio- CO2
NBio- CO2
Total CO2
CH4
N2O
CO2e
Category
tons/yr
MT/yr
Hauling

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Vendor

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Worker

2.8000e-
004

2.2000e-
004

2.9300e-
003

1.0000e-
005

9.9000e-
004

1.0000e-
005

9.9000e-
004

2.6000e-
004

1.0000e-
005

2.7000e-
004

0.0000

0.7727

0.7727

2.0000e-
005

2.0000e-
005

0.7791
Total

2.8000e-
004

2.2000e-
004

2.9300e-
003

1.0000e-
005

9.9000e-
004

1.0000e-
005

9.9000e-
004

2.6000e-
004

1.0000e-
005

2.7000e-
004

0.0000

0.7727

0.7727

2.0000e-
005

2.0000e-
005

0.7791
Mitigated Construction Off-Site

3.3 Grading - 2023
ROG
NOx
CO
SO2
Fugitive
PM10
Exhaust
PM10
PM10
Total
Fugitive
PM2.5
Exhaust
PM2.5
PM2.5
Total
Bio- CO2
NBio- CO2
Total CO2
CH4
N2O
CO2e
Category
tons/yr
MT/yr
Fugitive Dust

0.1611

0.0000

0.1611

0.0639

0.0000

0.0639

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Off-Road

0.0581

0.6040

0.4909

1.0900e-
003

0.0249

0.0249

0.0229

0.0229

0.0000

95.4366

95.4366

0.0309

0.0000

96.2083
Total

0.0581

0.6040

0.4909

1.0900e-
003

0.1611

0.0249

0.1860

0.0639

0.0229

0.0869

0.0000

95.4366

95.4366

0.0309

0.0000

96.2083
Unmitigated Construction On-Site
CalEEMod Version: CalEEMod.2020.4.0
Date: 11/8/2022 11:58 AM

Pedley Spreading Basins - South Coast Air Basin, Annual EMFAC Off-Model Adjustment Factors for Gasoline Light Duty Vehicle to Account for the SAFE Vehicle Rule Not Applied

3.3 Grading - 2023
ROG
NOx
CO
SO2
Fugitive
PM10
Exhaust
PM10
PM10
Total
Fugitive
PM2.5
Exhaust
PM2.5
PM2.5
Total
Bio- CO2
NBio- CO2
Total CO2
CH4
N2O
CO2e
Category
tons/yr
MT/yr
Hauling

5.0000e-
005

3.2400e-
003

8.6000e-
004

1.0000e-
005

4.3000e-
004

2.0000e-
005

4.5000e-
004

1.2000e-
004

2.0000e-
005

1.4000e-
004

0.0000

1.4395

1.4395

9.0000e-
005

2.3000e-
004

1.5099
Vendor

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Worker

1.0900e-
003

8.4000e-
004

0.0114

3.0000e-
005

3.8400e-
003

2.0000e-
005

3.8600e-
003

1.0200e-
003

2.0000e-
005

1.0400e-
003

0.0000

3.0049

3.0049

8.0000e-
005

8.0000e-
005

3.0298
Total

1.1400e-
003

4.0800e-
003

0.0123

4.0000e-
005

4.2700e-
003

4.0000e-
005

4.3100e-
003

1.1400e-
003

4.0000e-
005

1.1800e-
003

0.0000

4.4444

4.4444

1.7000e-
004

3.1000e-
004

4.5398
Unmitigated Construction Off-Site
ROG
NOx
CO
SO2
Fugitive
PM10
Exhaust
PM10
PM10
Total
Fugitive
PM2.5
Exhaust
PM2.5
PM2.5
Total
Bio- CO2
NBio- CO2
Total CO2
CH4
N2O
CO2e
Category
tons/yr
MT/yr
Fugitive Dust

0.0725

0.0000

0.0725

0.0288

0.0000

0.0288

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Off-Road

0.0581

0.6040

0.4909

1.0900e-
003

0.0249

0.0249

0.0229

0.0229

0.0000

95.4365

95.4365

0.0309

0.0000

96.2082
Total

0.0581

0.6040

0.4909

1.0900e-
003

0.0725

0.0249

0.0974

0.0288

0.0229

0.0517

0.0000

95.4365

95.4365

0.0309

0.0000

96.2082
Mitigated Construction On-Site
CalEEMod Version: CalEEMod.2020.4.0
Date: 11/8/2022 11:58 AM

Pedley Spreading Basins - South Coast Air Basin, Annual EMFAC Off-Model Adjustment Factors for Gasoline Light Duty Vehicle to Account for the SAFE Vehicle Rule Not Applied

3.3 Grading - 2023
ROG
NOx
CO
SO2
Fugitive
PM10
Exhaust
PM10
PM10
Total
Fugitive
PM2.5
Exhaust
PM2.5
PM2.5
Total
Bio- CO2
NBio- CO2
Total CO2
CH4
N2O
CO2e
Category
tons/yr
MT/yr
Hauling

5.0000e-
005

3.2400e-
003

8.6000e-
004

1.0000e-
005

4.3000e-
004

2.0000e-
005

4.5000e-
004

1.2000e-
004

2.0000e-
005

1.4000e-
004

0.0000

1.4395

1.4395

9.0000e-
005

2.3000e-
004

1.5099
Vendor

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Worker

1.0900e-
003

8.4000e-
004

0.0114

3.0000e-
005

3.8400e-
003

2.0000e-
005

3.8600e-
003

1.0200e-
003

2.0000e-
005

1.0400e-
003

0.0000

3.0049

3.0049

8.0000e-
005

8.0000e-
005

3.0298
Total

1.1400e-
003

4.0800e-
003

0.0123

4.0000e-
005

4.2700e-
003

4.0000e-
005

4.3100e-
003

1.1400e-
003

4.0000e-
005

1.1800e-
003

0.0000

4.4444

4.4444

1.7000e-
004

3.1000e-
004

4.5398
Mitigated Construction Off-Site

3.4 Utilities - 2023
ROG
NOx
CO
SO2
Fugitive
PM10
Exhaust
PM10
PM10
Total
Fugitive
PM2.5
Exhaust
PM2.5
PM2.5
Total
Bio- CO2
NBio- CO2
Total CO2
CH4
N2O
CO2e
Category
tons/yr
MT/yr
Fugitive Dust

0.1611

0.0000

0.1611

0.0639

0.0000

0.0639

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Off-Road

0.0581

0.6040

0.4909

1.0900e-
003

0.0249

0.0249

0.0229

0.0229

0.0000

95.4366

95.4366

0.0309

0.0000

96.2083
Total

0.0581

0.6040

0.4909

1.0900e-
003

0.1611

0.0249

0.1860

0.0639

0.0229

0.0869

0.0000

95.4366

95.4366

0.0309

0.0000

96.2083
Unmitigated Construction On-Site
CalEEMod Version: CalEEMod.2020.4.0
Date: 11/8/2022 11:58 AM

Pedley Spreading Basins - South Coast Air Basin, Annual EMFAC Off-Model Adjustment Factors for Gasoline Light Duty Vehicle to Account for the SAFE Vehicle Rule Not Applied

3.4 Utilities - 2023
ROG
NOx
CO
SO2
Fugitive
PM10
Exhaust
PM10
PM10
Total
Fugitive
PM2.5
Exhaust
PM2.5
PM2.5
Total
Bio- CO2
NBio- CO2
Total CO2
CH4
N2O
CO2e
Category
tons/yr
MT/yr
Hauling

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Vendor

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Worker

1.0900e-
003

8.4000e-
004

0.0114

3.0000e-
005

3.8400e-
003

2.0000e-
005

3.8600e-
003

1.0200e-
003

2.0000e-
005

1.0400e-
003

0.0000

3.0049

3.0049

8.0000e-
005

8.0000e-
005

3.0298
Total

1.0900e-
003

8.4000e-
004

0.0114

3.0000e-
005

3.8400e-
003

2.0000e-
005

3.8600e-
003

1.0200e-
003

2.0000e-
005

1.0400e-
003

0.0000

3.0049

3.0049

8.0000e-
005

8.0000e-
005

3.0298
Unmitigated Construction Off-Site
ROG
NOx
CO
SO2
Fugitive
PM10
Exhaust
PM10
PM10
Total
Fugitive
PM2.5
Exhaust
PM2.5
PM2.5
Total
Bio- CO2
NBio- CO2
Total CO2
CH4
N2O
CO2e
Category
tons/yr
MT/yr
Fugitive Dust

0.0725

0.0000

0.0725

0.0288

0.0000

0.0288

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Off-Road

0.0581

0.6040

0.4909

1.0900e-
003

0.0249

0.0249

0.0229

0.0229

0.0000

95.4365

95.4365

0.0309

0.0000

96.2082
Total

0.0581

0.6040

0.4909

1.0900e-
003

0.0725

0.0249

0.0974

0.0288

0.0229

0.0517

0.0000

95.4365

95.4365

0.0309

0.0000

96.2082
Mitigated Construction On-Site
CalEEMod Version: CalEEMod.2020.4.0
Date: 11/8/2022 11:58 AM

Pedley Spreading Basins - South Coast Air Basin, Annual EMFAC Off-Model Adjustment Factors for Gasoline Light Duty Vehicle to Account for the SAFE Vehicle Rule Not Applied

3.4 Utilities - 2023
ROG
NOx
CO
SO2
Fugitive
PM10
Exhaust
PM10
PM10
Total
Fugitive
PM2.5
Exhaust
PM2.5
PM2.5
Total
Bio- CO2
NBio- CO2
Total CO2
CH4
N2O
CO2e
Category
tons/yr
MT/yr
Hauling

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Vendor

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Worker

1.0900e-
003

8.4000e-
004

0.0114

3.0000e-
005

3.8400e-
003

2.0000e-
005

3.8600e-
003

1.0200e-
003

2.0000e-
005

1.0400e-
003

0.0000

3.0049

3.0049

8.0000e-
005

8.0000e-
005

3.0298
Total

1.0900e-
003

8.4000e-
004

0.0114

3.0000e-
005

3.8400e-
003

2.0000e-
005

3.8600e-
003

1.0200e-
003

2.0000e-
005

1.0400e-
003

0.0000

3.0049

3.0049

8.0000e-
005

8.0000e-
005

3.0298
Mitigated Construction Off-Site

3.5 Paving - 2023
ROG
NOx
CO
SO2
Fugitive
PM10
Exhaust
PM10
PM10
Total
Fugitive
PM2.5
Exhaust
PM2.5
PM2.5
Total
Bio- CO2
NBio- CO2
Total CO2
CH4
N2O
CO2e
Category
tons/yr
MT/yr
Off-Road

0.0103

0.1019

0.1458

2.3000e-
004

5.1000e-
003

5.1000e-
003

4.6900e-
003

4.6900e-
003

0.0000

20.0269

20.0269

6.4800e-
003

0.0000

20.1888
Paving

7.0000e-
005

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Total

0.0104

0.1019

0.1458

2.3000e-
004

5.1000e-
003

5.1000e-
003

4.6900e-
003

4.6900e-
003

0.0000

20.0269

20.0269

6.4800e-
003

0.0000

20.1888
Unmitigated Construction On-Site
CalEEMod Version: CalEEMod.2020.4.0
Date: 11/8/2022 11:58 AM

Pedley Spreading Basins - South Coast Air Basin, Annual EMFAC Off-Model Adjustment Factors for Gasoline Light Duty Vehicle to Account for the SAFE Vehicle Rule Not Applied

3.5 Paving - 2023
ROG
NOx
CO
SO2
Fugitive
PM10
Exhaust
PM10
PM10
Total
Fugitive
PM2.5
Exhaust
PM2.5
PM2.5
Total
Bio- CO2
NBio- CO2
Total CO2
CH4
N2O
CO2e
Category
tons/yr
MT/yr
Hauling

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Vendor

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Worker

4.7000e-
004

3.6000e-
004

4.8900e-
003

1.0000e-
005

1.6500e-
003

1.0000e-
005

1.6600e-
003

4.4000e-
004

1.0000e-
005

4.5000e-
004

0.0000

1.2878

1.2878

3.0000e-
005

3.0000e-
005

1.2985
Total

4.7000e-
004

3.6000e-
004

4.8900e-
003

1.0000e-
005

1.6500e-
003

1.0000e-
005

1.6600e-
003

4.4000e-
004

1.0000e-
005

4.5000e-
004

0.0000

1.2878

1.2878

3.0000e-
005

3.0000e-
005

1.2985
Unmitigated Construction Off-Site
ROG
NOx
CO
SO2
Fugitive
PM10
Exhaust
PM10
PM10
Total
Fugitive
PM2.5
Exhaust
PM2.5
PM2.5
Total
Bio- CO2
NBio- CO2
Total CO2
CH4
N2O
CO2e
Category
tons/yr
MT/yr
Off-Road

0.0103

0.1019

0.1458

2.3000e-
004

5.1000e-
003

5.1000e-
003

4.6900e-
003

4.6900e-
003

0.0000

20.0268

20.0268

6.4800e-
003

0.0000

20.1888
Paving

7.0000e-
005

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Total

0.0104

0.1019

0.1458

2.3000e-
004

5.1000e-
003

5.1000e-
003

4.6900e-
003

4.6900e-
003

0.0000

20.0268

20.0268

6.4800e-
003

0.0000

20.1888
Mitigated Construction On-Site
CalEEMod Version: CalEEMod.2020.4.0
Date: 11/8/2022 11:58 AM

Pedley Spreading Basins - South Coast Air Basin, Annual EMFAC Off-Model Adjustment Factors for Gasoline Light Duty Vehicle to Account for the SAFE Vehicle Rule Not Applied

3.5 Paving - 2023
ROG
NOx
CO
SO2
Fugitive
PM10
Exhaust
PM10
PM10
Total
Fugitive
PM2.5
Exhaust
PM2.5
PM2.5
Total
Bio- CO2
NBio- CO2
Total CO2
CH4
N2O
CO2e
Category
tons/yr
MT/yr
Hauling

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Vendor

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Worker

4.7000e-
004

3.6000e-
004

4.8900e-
003

1.0000e-
005

1.6500e-
003

1.0000e-
005

1.6600e-
003

4.4000e-
004

1.0000e-
005

4.5000e-
004

0.0000

1.2878

1.2878

3.0000e-
005

3.0000e-
005

1.2985
Total

4.7000e-
004

3.6000e-
004

4.8900e-
003

1.0000e-
005

1.6500e-
003

1.0000e-
005

1.6600e-
003

4.4000e-
004

1.0000e-
005

4.5000e-
004

0.0000

1.2878

1.2878

3.0000e-
005

3.0000e-
005

1.2985
Mitigated Construction Off-Site

4.0 Operational Detail - Mobile

4.1 Mitigation Measures Mobile
CalEEMod Version: CalEEMod.2020.4.0
Date: 11/8/2022 11:58 AM

Pedley Spreading Basins - South Coast Air Basin, Annual EMFAC Off-Model Adjustment Factors for Gasoline Light Duty Vehicle to Account for the SAFE Vehicle Rule Not Applied

ROG
NOx
CO
SO2
Fugitive
PM10
Exhaust
PM10
PM10
Total
Fugitive
PM2.5
Exhaust
PM2.5
PM2.5
Total
Bio- CO2
NBio- CO2
Total CO2
CH4
N2O
CO2e
Category
tons/yr
MT/yr
Mitigated

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Unmitigated

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

4.2 Trip Summary Information

4.3 Trip Type Information
Average Daily Trip Rate
Unmitigated
Mitigated
Land Use
Weekday
Saturday
Sunday
Annual VMT
Annual VMT
Other Asphalt Surfaces

0.00 0.00

0.00 Other Non-Asphalt Surfaces

0.00 0.00

0.00 Total

0.00 0.00

0.00 Miles
Trip %
Trip Purpose %
Land Use
H-W or C-W
H-S or C-C
H-O or C-NW
H-W or C-W
H-S or C-C
H-O or C-NW
Primary
Diverted
Pass-by
Other Asphalt Surfaces

16.60 8.40

6.90 0.00

0.00 0.00
0 0
0 Other Non-Asphalt Surfaces

16.60 8.40

6.90 0.00

0.00 0.00
0 0
0 4.4 Fleet Mix
Land Use
LDA
LDT1
LDT2
MDV
LHD1
LHD2
MHD
HHD
OBUS
UBUS
MCY
SBUS
MH
Other Asphalt Surfaces

0.543401

0.061496

0.184986

0.128935

0.023820

0.006437

0.011961

0.008652

0.000812

0.000508

0.024540

0.000745

0.003706
Other Non-Asphalt Surfaces

0.543401

0.061496

0.184986

0.128935

0.023820

0.006437

0.011961

0.008652

0.000812

0.000508

0.024540

0.000745

0.003706

5.0 Energy Detail
CalEEMod Version: CalEEMod.2020.4.0
Date: 11/8/2022 11:58 AM

Pedley Spreading Basins - South Coast Air Basin, Annual EMFAC Off-Model Adjustment Factors for Gasoline Light Duty Vehicle to Account for the SAFE Vehicle Rule Not Applied

ROG
NOx
CO
SO2
Fugitive
PM10
Exhaust
PM10
PM10
Total
Fugitive
PM2.5
Exhaust
PM2.5
PM2.5
Total
Bio- CO2
NBio- CO2
Total CO2
CH4
N2O
CO2e
Category
tons/yr
MT/yr
Electricity
Mitigated

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
Electricity
Unmitigated

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
NaturalGas
Mitigated

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000
NaturalGas
Unmitigated

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

5.1 Mitigation Measures Energy
Historical Energy Use: N
CalEEMod Version: CalEEMod.2020.4.0
Date: 11/8/2022 11:58 AM