Brentwood City Council
February 10, 2026

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-55 February 2026 disposal of contaminated environmental media (including affected media identified in prior environmental investigations conducted within the project site) that is above applicable ESLs.

The SMP shall be implemented throughout all ground-disturbing work.

The SMP shall also establish protocols and measures for addressing the discovery of presently unknown environmental conditions or subsurface structures such as underground storage tanks or sumps. If unknown environmental conditions or subsurface structures are uncovered, as directed by an oversight agency, additional site investigation and characterization may be required prior to construction to ensure that potential impacts do not exceed applicable regulatory thresholds. If additional site investigation and characterization are required prior to construction, the County or its contractor(s) shall implement said studies (and their respective recommendations, if necessary) prior to construction.
c) Would the project emit hazardous emissions or involve handling hazardous or acutely hazardous materials, substances, or waste within 0.25 mile of an existing or proposed school? The project would be located directly across from the Goddard School of Brentwood on Technology Way, a pre-school. However, as mentioned under Impact a, the routine transport, use, or disposal of hazardous materials would result in less-than-significant impacts with adherence to all applicable regulations and implementation of a SWPPP as part of Construction General Permit requirements.

Long-term use of hazardous materials would involve materials that are typically used in maintenance activities. Such materials are considered common. They are unlikely to be stored or used in large quantities or travel far, reducing the potential of a significant impact.

As mentioned under Impact b, portions of on-site soils are classified as California hazardous (or non‐ RCRA hazardous) waste. Implementation of Mitigation Measure HAZ-1 (refer to Impact b) would reduce the potential exposure impacts for construction personnel and the surrounding environment (including nearby schools) to a negligible level. Therefore, the project would have a less-thansignificant impact with mitigation incorporated.

Mitigation Measure HAZ-1: Soil Management Plan
Refer to Impact b, above.
d) Would the project be located on a site that is included on a list of hazardous materials sites compiled pursuant to Government Code Section 65962.5 and, as a result, create a significant hazard to the public or the environment?
The 2025 Phase I ESA did not identify any hazardous material release sites within the southern site.

In addition, an environmental database search conducted in July 2025 by ICF (using SWRCB’s GeoTracker, Department of Toxic Substances Control’s [DTSC’s] EnviroStor, and California Environmental Protection Agency’s [CalEPA’s] Cortese List Data Resources) did not identify any hazardous materials sites that would qualify as a Cortese List12 site within the southern portion of 12 U.S.C. Section 65962.5 (Cortese List) includes DTSC-listed hazardous waste facilities and sites, Department of Health Services lists of contaminated drinking water wells, sites listed by SWRCB as having underground storage tank leaks or a discharge of hazardous wastes or materials into the water or groundwater, and lists from local regulatory agencies of sites with a known migration of hazardous waste/material. Specifically, the following resources provide information regarding facilities meeting “Cortese List” requirements:
• List of hazardous waste and substances sites from DTSC’s EnviroStor database.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-56 February 2026 the project site evaluated in the 2025 Phase I ESA or the northern portion of the project site.

Therefore, the project would have no impact.
e) For a project located within an airport land use plan or, where such a plan has not been adopted, within 2 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? The project site is not located within an airport land use plan or within 2 miles of a public airport or public use airport. The closest airports to the project site are Funny Farm Airport, a privately owned airport approximately 2.7 miles east of the project site in the city of Brentwood, and Byron Airport, a public airport approximately 8.2 miles southeast of the project site in Byron. Therefore, the project would have no impact.
f) Would the project impair implementation of or physically interfere with an adopted emergency response plan or emergency evacuation plan?
As discussed in Section 2.17, Transportation, operation of the proposed project would not have substantial traffic impacts. The proposed access points to the project site would be designed and constructed to comply with City of Brentwood and Contra Costa County standards regarding geometric design to provide users with adequate sight distance visibility and would meet all emergency access standards and compliance would be verified by both agencies prior to and after construction. Furthermore, the proposed project would not alter the existing surrounding street grid during operation. There are no other attributes of the proposed project that would have the potential to interfere with implementation of any emergency response plan prepared by the City or emergency response procedures adopted by any local service providers. The County has not adopted an emergency response plan for the Brentwood area, and thus the project would not impair implementation of or physically interfere with such a plan. The Emergency Alert System and Emergency Digital Information Service are the primary systems used to inform the public of emergencies and threats to health, safety, and welfare. These systems are electronic and are operated by government agencies in conjunction with televisions and radios. In the event of an emergency, these systems are used to broadcast emergency information, such as evacuation alerts, across all radio and television stations in the affected area. Due to the electronic nature of these systems, there is no possibility they would be impacted by the project. Based on the above, the proposed project would not impair implementation of or interfere with an adopted emergency response plan or emergency evacuation plan. Therefore, the project would have a less-thansignificant impact. g) Would the project expose people or structures, either directly or indirectly, to a significant risk of loss, injury or death involving wildland fires?
The project site is in a developed area of Brentwood with no wildlands intermixed. Land uses surrounding the project site include commercial (east and north) and residential (west and south). A vacant lot is located between residential uses to the south and the project site. According to the California Department of Forestry and Fire Protection’s (CAL FIRE’s) State Responsibility Area Fire • List of leaking underground storage tank sites from SWRCB’s GeoTracker database. • List of solid waste disposal sites identified by SWRCB with waste constituents above hazardous levels. • List of “active” cease-and-desist orders and cleanup and abatement orders from SWRCB. • List of hazardous waste facilities subject to corrective action pursuant to Section 25187.5 of the Health and Safety Code, as identified by DTSC.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-57 February 2026 Hazard Severity Zones, Contra Costa County Map (California Department of Forestry and Fire Protection [CAL FIRE] 2023), the project site is not within a Very High, High, or Moderate Fire Hazard Severity Zone. The closest high fire area is approximately 2.75 miles west of the project site, beyond SR 4. Thus, the project would not exacerbate wildfire risks of any nature. It is not located in or near a Fire Hazard Severity Zone. Therefore, the project would have no impact.

2.9.2 Sources of Information
Baseline Environmental Consulting, Inc. 2024. Soil Investigation Report, Proposed East County Service Center, Contra Costa County Project # WH429A, Brentwood, California. Final. 24201‐01.

Brentwood, CA [Prepared for
Environmental Services Division Contra Costa County Public Works Department, Martinez, CA]. ———.2025a. Phase I Environmental Site Assessment, Proposed East County Service Center (Southern Site), Contra Costa County Project # WH429A, Brentwood, California. Final. 24201‐01. Brentwood, CA [Prepared for the Contra Costa County Public Works Department, Martinez, CA]. ———. 2025b. Phase II Environmental Site Assessment, Proposed East County Service Center Southern Property, Assessor’s Parcel Number 0.16-120-024, Contra Costa County Project # WH429A, Brentwood, California. Final. 24201‐01. Brentwood, CA [Prepared for Environmental Services Division Contra Costa County Public Works Department, Martinez, CA]. ———. 2025c. Peer Review of ACC Letter Regarding Management of Pesticide-Containing Soils, Planned East County Service Center, Brentwood, California. 24201‐01.

California Department of Forestry and Fire Protection. 2023. State Responsibility Area Fire Hazard Severity Zones. Available: hhttps://calfire.app.box.com/s/viyymvmweaaciuhwfb2bdxqdok3zo0ke/ file/1483768131659. Accessed: September 16, 2025.

State Water Resources Control Board. 2025. Welcome to the Construction Stormwater Program.

Available: https://www.waterboards.ca.gov/water_issues/programs/stormwater/ construction.html. Accessed: July 10, 2025.

2.10 Hydrology and Water Quality
Potentially
Significant
Impact
Less than
Significant with
Mitigation
Incorporated
Less-thanSignificant
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 groundwater supplies or interfere substantially with groundwater recharge such that the project may impede sustainable groundwater management of the
basin?
c) Substantially alter the existing drainage pattern of the site or area, including through the alteration of the course of a stream or river or through the addition of impervious surfaces, in a manner that would:
i) Result in substantial erosion or siltation on- or off-site, □
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Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-58 February 2026 Potentially
Significant
Impact
Less than
Significant with
Mitigation
Incorporated
Less-thanSignificant
Impact No Impact
Would the project:
ii) Substantially increase the rate or amount of surface runoff in a manner that would result in flooding on- or off-site; iii) Create or contribute runoff water that would exceed the capacity of existing or planned stormwater drainage
systems or provide substantial additional sources of
polluted runoff; or
iv) Impede or redirect floodflows?
d) In flood hazard, tsunami, or seiche zones, risk release of pollutants due to project inundation?
e) Conflict with or obstruct implementation of a water quality control plan or sustainable groundwater management plan?

2.10.1 Discussion
a) Would the project violate any water quality standards or waste discharge requirements or otherwise substantially degrade surface or groundwater quality?
Construction activities associated with the proposed project include ground-disturbing activities such as trenching, backfilling, and grading. Ground-disturbing activities and runoff from work areas could cause soil erosion and sedimentation, reducing water quality. Marsh Creek is less than 0.2 mile northwest of the project site. The potential impacts on water quality are related to sediment and sediment-bound pollutants that may be mobilized into drainage structures or other water bodies. In addition, common hazardous materials (e.g., gasoline, oils, grease, lubricants) from construction equipment could be accidentally released during construction. Accidental discharge of hazardous materials to surface waters during construction could temporarily adversely affect water quality or result in a violation of water quality standards. Contaminants from construction vehicles and equipment and sediment from soil erosion could increase the pollutant load in runoff being transported to receiving waters.

The project would include preparation and implementation of a SWPPP that would be consistent with the Statewide Construction General Permit (Order No. 2022-0057-DWQ). The SWPPP would detail the construction-phase erosion and sediment control BMPs and the housekeeping measures for control of contaminants other than sediment. Erosion control BMPs include source control measures, such as wetting dry and dusty surfaces to prevent fugitive dust emissions and installing an effective soil cover (e.g., geotextiles, straw mulch) or hydroseeding, for inactive areas to prevent sediments from being dislodged by wind, rain, or flowing water. Sediment control BMPs would include measures such as the installation of fiber rolls and sediment basins to capture and remove particles that have already been dislodged. The SWPPP would establish good housekeeping measures such as construction vehicle storage and maintenance, handling procedures for hazardous materials, and waste management BMPs, which would include procedural and structural measures to prevent the release of wastes generated and materials used at the site. The SWPPP also would detail spill prevention and control measures to identify the proper storage and handling techniques for fuels and lubricants and the procedures to follow in the event of a spill. □
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Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-59 February 2026 The project would introduce impervious surfaces that could transport sediment and hazardous substances into area storm drain inlets that drain into waterways. Because of the addition of new impervious surfaces, concentrated polluted flows would increase. Provision C.3 of the San Francisco Bay Region Municipal Regional Stormwater National Pollutant Discharge Elimination System Permit (MRP) requires all projects creating and/or redeveloping at least 5,000 square feet of impervious surface to incorporate stormwater management treatment facilities. The project would create approximately 213,897 square feet (4.91 acres) of impervious surface cover, totaling 62 percent of the project site. However, the project would also include the installation of stormwater treatment basins, permeable pavers, and landscaping. These features would decrease the rate and volume of stormwater runoff, treat runoff, and allow runoff to infiltrate prior to discharge. In accordance with Provision C.3, a Stormwater Control Plan (SWCP) would be prepared and submitted for review and approval by the Contra Costa County Public Works Department, in compliance with the Stormwater Management and Discharge Control Ordinance (Section 1014) and the MRP.

All project activities would be subject to existing regulatory requirements. During operation, the proposed project would be required to meet all applicable water quality objectives for surface waters and groundwater contained in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins (Basin Plan), would be operated and maintained in accordance with related regulatory agency guidelines, and would meet the goals and objectives of the County General Plan. Furthermore, the discharge of pollutants from urban runoff would be minimized with implementation of practices required by the County Clean Water Program and other County, federal, and state requirements. Therefore, construction and operation would not violate water quality standards or waste discharge requirements. Therefore, the project would have a less-thansignificant impact. b) Would the project substantially decrease groundwater supplies or interfere substantially with groundwater recharge such that the project may impede sustainable groundwater management of the basin?
The project site is within the San Joaquin Valley Groundwater Basin – East Contra Costa Subbasin.

Because the East Contra Costa Subbasin is considered a medium-priority basin, a groundwater sustainability plan (GSP) is required. On May 9, 2017, eight agencies entered a memorandum of understanding for development and implementation of the East Contra Costa Subbasin GSP.

Implementation of the project would increase the impervious area within the project site. However, the project site would be developed with stormwater treatment basins, permeable pavers, and landscaping. These features would decrease the volume of stormwater runoff, treat runoff, and allow runoff to infiltrate prior to discharge into the municipal storm drain. Recharge in the area would continue to occur through infiltration of precipitation. Groundwater pumping or dewatering may be required during project construction because the geotechnical report indicated that groundwater is deeper than 20 feet, which is above the maximum depth of project excavation for the geothermal borings. However, groundwater supplies would not be used during project operation.

Therefore, the project would have a less-than-significant impact.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-60 February 2026 c) Would the project substantially alter the existing drainage pattern of the site or area, including through the alteration of the course of a stream or river or through the addition of impervious surfaces, in a manner that would:
i) Result in substantial erosion or siltation on- or off-site, During construction, existing drainage patterns could temporarily be altered through minor grading, potentially resulting in temporarily increased erosion. BMPs would be implemented to manage runoff and potential erosion, as described in the SWPPP, in compliance with the Construction General Permit. Good housekeeping practices identified in the SWPPP would prevent runoff and contain any associated sediment.

Implementation of the project would result in the addition of impervious surface cover. However, the project site would include stormwater treatment basins and landscaping, which would decrease stormwater runoff and any mobilization of sediment. As a result, excess soil disturbance would be minimized, and associated soil erosion and siltation impacts would also be reduced. Therefore, the project would have a less-than-significant impact.
ii) Substantially increase the rate or amount of surface runoff in a manner that would result in flooding on- or off-site;
During construction, existing drainage patterns could temporarily be altered, potentially resulting in increased runoff or flooding. BMPs identified in the SWPPP, in compliance with the Construction General Permit, would be implemented to minimize runoff or flooding. The project would result in an increase in impervious surface area compared to existing conditions. An increase in impervious cover could result in increased surface runoff rates and volumes. However, the project site would include stormwater treatment basins, permeable pavers, and landscaping.

These features would decrease the rate and volume of stormwater runoff and allow runoff to infiltrate prior to discharge into the municipal storm drain. Because the project would create more than 1 acre of impervious surface area, an SWCP would also be required. Runoff would be managed according to the approved SWCP to ensure that site drainage features are appropriately sized and connected to drainage infrastructure off-site. Therefore, the project would have a lessthan-significant impact. iii) Create or contribute runoff water that would exceed the capacity of existing or planned stormwater drainage systems or provide substantial additional sources of polluted runoff; or The project site is currently an undeveloped lot with no stormwater infrastructure serving the site. New stormwater infrastructure is proposed that would connect to the existing municipal drainage facilities. Because the project would create more than 1 acre of impervious surface area, an SWCP will be required. Runoff would be managed according to the approved SWCP to ensure that site drainage features would be appropriately sized and connected to drainage infrastructure off-site. In addition, the project site would include stormwater treatment basins, permeable pavers, and landscaping. These features would decrease the rate and volume of stormwater runoff and treat runoff prior to discharge. The project would not create or contribute runoff water that would exceed the capacity of existing or planned stormwater drainage systems or provide substantial additional sources of polluted runoff. Therefore, the project would have a less-thansignificant impact.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-61 February 2026 iv) impede or redirect floodflows?
During construction, the drainage pattern of the site may be temporarily altered. However, the project site is within FEMA Zone X, outside of the 100-year floodplain (FEMA 2017). The project would manage runoff flows through implementation of the approved SWCP as well through design features, including stormwater treatment basins. The project would not impede or redirect floodflows. Therefore, the project would have no impact. d) Would the project, in flood hazard, tsunami, or seiche zones, risk release of pollutants due to project inundation?
The project site is within Federal Emergency Management Agency (FEMA) Zone X, an area of minimal flood hazard, outside of the 100-year floodplain (FEMA 2017). The project site is approximately 24 miles southeast of the Carquinez Strait and not within a mapped tsunami inundation zone (State of California 2021). There are no reservoirs adjacent to the project site; therefore, the project would not be prone to inundation by seiche. The project would not release pollutants due to project inundation. Therefore, the project would have no impact. e) Would the project conflict with or obstruct implementation of a water quality control plan or sustainable groundwater management plan?
The proposed project would comply with the applicable water quality objectives for the region. As part of compliance with permit requirements during ground-disturbing or construction activities, implementation of water quality control measures and BMPs would ensure that water quality standards would be achieved, including the water quality objectives that protect designated beneficial uses of surface and groundwater, as defined in the Basin Plan. The National Pollutant Discharge Elimination System (NPDES) Construction General Permit also requires stormwater discharges not to contain pollutants that cause or contribute to an exceedance of any applicable water quality objectives or water quality standards, including designated beneficial uses. In addition, implementing the appropriate County General Plan policies would require the protection of groundwater recharge areas and groundwater resources, as required by the East Contra Costa Subbasin GSP. Therefore, the project would have no impact.

2.10.2 Sources of Information
Federal Emergency Management Agency. 2017. National Flood Hazard Layer Viewer. Map #06013C0354G, dated March 21, 2017. Available: https://hazards-fema.maps.arcgis.com/apps/ webappviewer/index.html?id=8b0adb51996444d4879338b5529aa9cd. Accessed: July 2, 2025.

State of California. 2021. Tsunami Hazard Area Map, Contra Costa County (displayed at multiple scales). Produced by the California Geological Survey and the Governor’s Office of Emergency Services.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-62 February 2026

2.11 Land Use and Planning
Potentially
Significant
Impact
Less than
Significant with
Mitigation
Incorporated
Less-thanSignificant
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?

2.11.1 Discussion
a) Would the project physically divide an established community? The project site is a flat, undeveloped lot bordered by residential uses to the west, commercial uses to the north and east across Brentwood Boulevard, and a grassy undeveloped area to the south. The proposed project does not include features, such as new roads or barriers, that would divide an existing community. Therefore, the project would have no impact. b) Would the project 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? County General Plan policies apply to the proposed improvements within the project site because the site is owned by the County. There is no County General Plan designation for the project site because the site is in the city of Brentwood (County 2024). However, the proposed project would be generally consistent with County General Plan goals and policies adopted for the purpose of avoiding or mitigating an environmental effect because it would be consistent with maximum development projections (Policy LU-P1.1), contain development within the urban limit line (Policy LU-P2.1), and encourage infill development (Policy LU-P2.5). In addition, the proposed project would be required to implement the additional construction measures identified in the Air District’s CEQA Guidelines to reduce construction air pollutant emissions (Policy HS-P1.9), prohibit nonessential diesel engine idling Countywide as well as nonessential idling of all vehicles within 100 feet of sensitive receptors (Policy HS-P1.10), and prioritize implementation of the Contra Costa County Climate Action and Adaptation Plan to reduce GHG emissions (Policy HS-P3.1). The proposed project would also adhere to the County General Plan policies related to noise and vibration, such as Policy HS-P14.1, which requires a noise analysis; Policy HS-P14.3, which requires an interior noise level analysis; and Policy HS-P14.5, which requires noise mitigation for noise impacts. Any proposed improvements within the public right-of-way or outside of the project site would be subject to City requirements.

Because the project site is owned by the County, neither the County land use/zoning designations nor the City land use/zoning designations apply to the project site. Any proposed improvements within the public right-of-way or outside of the project site would be subject to the requirements of the City. The proposed project is not required to comply with City General Plan designations or City zoning designations for the project site. The project’s consistency with the designations are provided below for informational purposes only. In the City General Plan, the project site is within an area designated for BP uses and subject to the Planned Development (PD-42) and BBSP zoning designation. The Planned Development (PD) designation identifies areas where a master planned □
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Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-63 February 2026 project has been approved and entitled and site-specific zoning has been established. The PD land use designation defaults to the zoning that is in place for the subject parcel (City of Brentwood 2014). In addition, the project site is partially located within the boundaries of the BBSP. The Business Park designation provides for integrated business and research parks, large individual corporate establishments, professional and administrative office centers, and light industrial complexes (City of Brentwood 2014). The proposed project is a centralized service center that would be consistent with the intent and assumptions of the Business Park and specific plan designations (City of Brentwood 2015).

Given the above, the project would not conflict with any applicable land use plan, policy, or regulation adopted for the purpose of avoiding or mitigating an environmental effect. The project would have no impact.

2.11.2 Sources of Information
City of Brentwood. 2014. General Plan. Adopted July 22, 2014. _______. 2015. Brentwood Boulevard Specific Plan. Adopted: March 27, 2012. Amended: October 27, 2015.

Contra Costa County. 2024. Contra Costa County 2045 General Plan. Adopted: November 5, 2024.

Available: https://www.contracosta.ca.gov/DocumentCenter/View/84957/Contra-CostaCounty-2045-General-Plan-PDF---Large-file-782-MB.

2.12 Mineral Resources
Potentially
Significant
Impact
Less than
Significant with
Mitigation
Incorporated
Less-thanSignificant
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 availability of a locally important mineral resource recovery site delineated on a local general plan, specific plan, or other land use plan?

2.12.1 Discussion
a) Would the project 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?
There are no mineral resources near or within the city of Brentwood, according to Figure COS-13, Mineral Resource Areas, of the County General Plan (County 2024). Therefore, the project would have no impact.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-64 February 2026 b) Would the project result in the loss of availability of a locally important mineral resource recovery site delineated on a local general plan, specific plan, or other land use plan? There are no mapped mineral resource areas at the project site. Therefore, the project would have no impact.

2.12.2 Sources of Information
Contra Costa County. 2024. Contra Costa County 2045 General Plan. Mineral Resources. Available:
https://www.contracosta.ca.gov/DocumentCenter/View/84957/Contra-Costa-County-2045- General-Plan-PDF---Large-file-782-MB.

2.13 Noise
Potentially
Significant
Impact
Less than
Significant with
Mitigation
Incorporated
Less-thanSignificant
Impact No Impact
Would the project:
a) Generate a substantial temporary or permanent increase in ambient noise levels in the vicinity of the project in excess of standards established in the local general plan or noise ordinance or applicable standards of other agencies?
b) Generate excessive groundborne vibration or groundborne noise levels?
c) For a project located within the vicinity of a private airstrip or an airport land use plan or, where such a plan has not been adopted, within 2 miles of a public airport or public use airport, expose people residing or working in the project area to excessive noise levels?

2.13.1 Discussion
Noise can be described as any loud, unexpected, or annoying sound. The loudness of the noise source and obstructions or atmospheric factors affecting the propagation path to the receptor determine the sound level and characteristics of the noise perceived by the receptor. The standard unit of measurement of the loudness of sound is the decibel (dB). Because the human ear is not equally sensitive to sound at all frequencies, the A-weighted decibel scale (dBA) was devised to relate noise to human sensitivity because it gives greater weight to the frequencies of sound to which the human ear is most sensitive. The human ear can detect changes in sound levels of approximately 3 dBA under normal conditions. A change of 5 dBA is noticeable to most people in an exterior environment.

Different metrics are used to evaluate the effects of noise on a community. The equivalent sound level (Leq) represents an average of the sound energy occurring over a specified period, typically 1 hour. The maximum sound level (Lmax) refers to the root-mean-square (rms) sound level corresponding to the loudest 1-second interval occurring during the measurement. The day/night level (Ldn, or DNL) is an average of all noise levels recorded over a 24-hour period, with a 10 dBA penalty added to noise levels occurring during nighttime hours between 10:00 p.m. and 7:00 a.m. □
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Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-65 February 2026 Existing Noise Environment in the Project Area
The primary source of existing noise in the project area is traffic on local roads, including Sand Creek Road, Brentwood Boulevard, Technology Way, and Business Circle Drive. Other noise sources include periodic aircraft overflights and general residential sources (e.g., air conditioners and landscaping equipment). The closest airports to the project site are Funny Farm Airport, a privately owned airport approximately 2.7 miles east of the project site in the city of Brentwood, and Byron Airport, a public airport approximately 8.2 miles southeast of the project site in Byron, California, a census-designated place in Contra Costa County.

To establish the existing noise environment, long-term noise monitoring was conducted at three locations from April 15 to 17, 2025. Figure 4 identifies the locations of the long-term measurement sites. The purpose of long-term noise measurements was to establish the existing day/night level in the project area and characterize the daily trend in noise levels throughout a 48-hour period.

Monitoring was conducted using Piccolo SLM-P3 Type 2 sound-level meters manufactured by Soft dB. These are considered general-purpose grade for field use. The sound-level meters were calibrated prior to the measurement to ensure accuracy using a Larson Davis CAL200 acoustical calibrator. The calibration was also re-checked at the conclusion of each measurement. The noise levels collected during monitoring are summarized in Table 2-11.

Table 2-11. Summary of Noise Measurements
Site Description
Averagea
24-Hour
Noise
Level
(dBA Ldn)
Average
Daytimeb
Noise Level
(dBA, 1-hour
Leq)
Average
Nighttimec
Noise Level
(dBA, 1-hour
Leq)
LT-1 West of project site at southern terminus of
Business Center Drive

62.4–63.6 62.1 54.4
LT-2 Northwest of the intersection of Technology
Way and Business Center Drive

63.4–63.6 61.9 55.4
LT-3 Hampton Inn Brentwood parking lot 62.2–63.0 60.6 54.7 Notes:
a. Ambient measurement data were collected from 11:00 a.m. on April 15, 2025, to 11:00 a.m. on April 17, 2025. b. Daytime is considered to be the hours between 7:00 a.m. and 10:00 p.m. c. Nighttime is considered to be the hours between 10:00 p.m. and 7:00 a.m. dBA = A-weighted decibel level (a logarithmic measurement scale that approximates the frequency response of the human ear); Ldn = day/night sound level (Ldn describes the average acoustical energy content of noise for a 24-hour period. Nighttime hours between 10:00 p.m. and 7:00 a.m. are assigned a 10 dB penalty to account for human sensitivity to noise at night); Leq = equivalent sound level (Leq describes the average acoustical energy content of noise for an identified period of time, commonly 1 hour)

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East Sand Creek Road
Scott Creek Way
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Curtis Drive
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Technology Way
Marsh Creek
Woodfield Lane
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Basemap Source: © Google 2025.

Google Earth Pro, Version 7.3.6. Mountain View, CA.

Image date: March 16, 2024. Accessed: May 14, 2025.
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Graphics … 104857 Co Contra Costa East County (12-8 -2025) Figure 4
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A

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-67 February 2026 Sensitive Receptors
Sensitive receptors are defined as locations that are sensitive to noise and vibration, such as residences, schools, hotels, and hospitals. As shown in Figure 4, the project site is surrounded by Technology Way to the north, Brentwood Boulevard and a Jack in the Box restaurant to the east, an undeveloped field to the south, and Business Center Drive and the Silvergate Apartments recreational facility to the west. Surrounding land uses and the closest noise-sensitive receptors include residential uses, the Goddard School of Brentwood, and Hampton Inn Brentwood. Multifamily residential complexes are approximately 60 feet west of the project site boundary. Singlefamily residential uses are about 180 feet southwest of the project boundary. The Goddard School of Brentwood is approximately 130 feet north of the project boundary. Lastly, Hampton Inn Brentwood is approximately 330 feet northeast of the project site boundary.

Federal Regulations
The Federal Transit Administration (FTA) has developed methods for evaluating construction noise levels, including guidelines for noise limits at sensitive land uses, to describe levels that may result in a negative community reaction. These are discussed in Chapter 7 of the Transit Noise and Vibration Impact Assessment Manual (FTA Manual) (2018). The methods and guidance in the FTA Manual are used to set noise limits if criteria specific to construction are not specified in a local ordinance or standard. Based on FTA’s general assessment methodology for residences, the guideline is 90 dBA, 1-hour Leq, during daytime hours (7:00 a.m. to 10:00 p.m.) and 80 dBA, 1-hour Leq, during nighttime hours (10:00 p.m. to 7:00 a.m.).

Vibration impact thresholds are discussed in Chapter 7 of the FTA Manual. The structures adjacent to the project site, the Jack in the Box restaurant and Silvergate Apartments recreational facility, are assumed to be a mix of reinforced concrete, steel, or timber (no plaster) for purposes of the vibration analysis prepared for the project. Building damage could result from a vibration level with a peak particle velocity [PPV] of 0.5 inch per second (102 vibration velocity decibels [VdB]). In addition, nearby residences (i.e., single- and multi-family residences) are assumed to be nonengineered timber and masonry buildings. For such structures, damage could result from a vibration level with a PPV of 0.2 inch per second (94 VdB). A construction-related vibration annoyance impact would occur if vibration levels from equipment were readily perceptible at a sensitive receiving land use (i.e., 86 VdB, which is the annoyance impact criterion for “occasional events”).

Local Regulations
Envision Contra Costa County 2045 General Plan
The County General Plan, adopted in November 2024, is the County’s primary policy framework for guiding physical development in unincorporated areas (Contra Costa County 2024). The County General Plan has a Health and Safety Element with goals, policies, and actions that promote a safe and comfortable noise environment throughout the county. Figure 5 is the land use compatibility matrix from the County General Plan.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-68 February 2026 Figure 5. Maximum Allowable Noise Exposure by Use
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Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-69 February 2026 For projects that are required by CEQA to analyze noise impacts, Policy HS-P14.5 states the following:

Protect noise-sensitive land uses listed in Table HS-3 [Figure 5, above] from adverse noise impacts by requiring mitigation to the degree feasible for projects that would increase long-term noise in excess of the following thresholds, when measured at the sensitive use’s property line:
• Greater than 1.5 dBA DNL increase for ambient noise environments of 65 dBA DNL and higher.
• Greater than 3 dBA DNL increase for ambient noise environments of 60 to 64 DNL. • Greater than 5 dBA DNL increase for ambient noise environments of less than 60 dBA DNL.

In addition, Policy HS-P14.6 states that County projects should be designed to minimize long-term noise impacts on existing residents and follow best practices to minimize short-term impacts from construction noise. With respect to short-term construction noise, Policy HS-P14.7 identifies condition entitlements to limit noise-generating construction activities to the following:
• Weekdays and non-holidays, unless site-specific conditions warrant exceptions. • Within 1,000 feet of noise-sensitive uses: 7:30 a.m. to 5:00 p.m. • More than 1,000 feet from noise-sensitive uses: 7:00 a.m. to 6:00 p.m.

The County Code of Ordinances does not provide specific thresholds or exterior noise standards for construction noise or noise from stationary equipment. Therefore, the EIR prepared for the County General Plan used substitute thresholds to assess noise impacts. With respect to construction noise, the EIR prepared for the County General Plan identified the FTA construction noise criterion of 80 dBA Leq (8 hours) as a suitable threshold to be used in assessing construction noise impacts at sensitive receptors. For assessing stationary equipment noise, the EIR prepared for the County General Plan considered the maximum allowable exterior noise levels for special events, which are included in Chapter 82-44.410(b) of the County Code of Ordinances. For purposes of EIR analysis, the standards are used to determine significant stationary noise impacts, with revised hours to include both daytime and nighttime periods. During daytime hours (7:00 a.m. to 7:00 p.m.) the allowable exterior noise level is 60 dBA L50. During nighttime hours (7:00 p.m. to 7:00 a.m.), the allowable exterior noise level is 55 dBA L50 (Contra Costa County 2024).13 Refer to Table 5.13-8 of the EIR prepared for the County General Plan for more details.

The City General Plan Noise Element contains goals, policies, and actions to promote a safe and comfortable noise environment throughout the city (City of Brentwood 2014). Figure 6 is the City land use compatibility matrix.
13 The noise metric L50 represents the noise level exceeded 50 percent of the time in a measurement period. An equivalent noise level (Leq) is the average noise level measured over a specific measurement period (typically 1 hour). For a conservative analysis of equipment noise levels, the equipment is assumed to run at full capacity for 1 hour. In doing this, L50 is conservatively assumed to be equivalent to Leq.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-70 February 2026 Figure 6. City General Plan Land Use Compatibility Matrix for Community Noise Environment For projects that are required by CEQA to analyze noise impacts, Policy N1-7 states the following:

Stationary and Non-Transportation Noise Sources
• A significant impact will occur if the project results in an exceedance of the noise level standards contained in this element or the project will result in an increase in ambient noise levels by more than 3 dB, whichever is greater.

Transportation Noise Sources
• Where existing traffic noise levels are less than 60 dB Ldn at the outdoor activity areas of noise-sensitive uses, a +5 dB Ldn increase in roadway noise levels will be considered significant;
• Where existing traffic noise levels range between 60 and 65 dB Ldn at the outdoor activity areas of noise-sensitive uses, a +3 dB Ldn increase in roadway noise levels will be considered significant; and
• Where existing traffic noise levels are greater than 65 dB Ldn at the outdoor activity areas of noise-sensitive uses, a +1.5 dB Ldn increase in roadway noise levels will be considered significant.

Multi-Family Residential, Hotels, and Motels
Outdoor Sports and Recreation, Neighborhood
Parks and Playgrounds
Schools, Libraries, Museums, Hospitals,
Personal Care, Meeting Halls, Churches
Office Buildings, Business
Commercial, and Professional
Industrial

NORMALLY ACCEPTABLE
Specified land use is satisfactory, based upon the assumption that any buildings involved are of normal conventional construction, without any special insulation requirements

CONDITIONALLY ACCEPTABLE
Specified land use may be permitted only a~er detailed analysis of the noise reduction requirements and needed noise insulation features included in the design

UNACCEPTABLE
New construction or development should generally not be undertaken because mitigation is usually not feasible to comply with noise element policies

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-71 February 2026 Policy N1-13 also provides the exterior noise-level standards for non-transportation-related noise when the receiving land use is residential. During daytime hours, 7:00 a.m. to 10:00 p.m., noise is limited to 55 dBA Leq and 70 dBA Lmax. During nighttime hours, 10:00 p.m. to 7:00 a.m., noise is limited to 45 dBA Leq and 65 dBA Lmax.

Lastly, Policy N1-15 requires construction activities to comply with standard best practices in Action N 1e, as outlined below.

Action N 1e: During the environmental review process, determine if proposed construction will constitute a significant impact on nearby residents and, if necessary, require mitigation measures in addition to the standard best practice controls. Suggested best practices for control of construction noise include:
• Noise-generating construction activities, including truck traffic coming to and from the construction site for any purpose, shall be limited to between the hours of 7:30 a.m. and 5:00 p.m. on weekdays. No construction shall occur on weekends or holidays; • All equipment driven by internal-combustion engines shall be equipped with mufflers that are in good condition and appropriate for the equipment; • The construction contractor shall utilize “quiet” models of air compressors and other stationary noise sources where technology exists;
• At all times during project grading and construction, stationary noise-generating equipment shall be located as far as practicable from sensitive receptors and placed so that emitted noise is directed away from residences;
• Unnecessary idling of internal-combustion engines shall be prohibited; • Construction staging areas shall be established at locations that will create the greatest distance between the construction-related noise sources and noise-sensitive receptors nearest the project site during all project construction activities, to the extent feasible; • The required construction-related noise mitigation plan shall also specify that haul-truck deliveries shall be subject to the same hours specified for construction equipment; • Neighbors located adjacent to the construction site shall be notified of the construction schedule in writing; and
• The construction contractor shall designate a “noise disturbance coordinator” who will be responsible for responding to any local complaints about construction noise. The disturbance coordinator shall be responsible for determining the cause of the noise complaint (e.g., starting too early, poor muffler) and instituting reasonable measures, as warranted, to correct the problem. A telephone number for the disturbance coordinator shall be conspicuously posted at the construction site.

Chapter 9.32, Noise Regulations, of the Brentwood Municipal Code contains the City’s standards and thresholds related to noise, which are intended to promote the health, comfort, safety, and welfare of residents. To accomplish this goal, Section 9.32.030(B) contains exterior noise-level standards for residential, commercial, and industrial land use zones. For the noise-sensitive land uses considered in this report, the applicable exterior noise limits are summarized in Table 2-12.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-72 February 2026 Table 2-12. Applicable City of Brentwood Exterior Noise Standards Noise Level that May Not Be
Exceeded for More than…
Noise
Metric
Descriptor
Residential
Daytime
(7:00 a.m. to 10:00
p.m.)
Nighttime
(10:00 p.m. to 7:00
a.m.)
30 minutes in any hour L50 60 dBA 45 dBA
15 minutes in any hour L25 65 dBA 50 dBA
5 minutes in any hour L8.33 70 dBA 55 dBA
1 minute in any hour L1.67 75 dBA 60 dBA
Anytime (i.e., maximum noise level) Lmax 80 dBA 65 dBA
Note: If the measured ambient noise level exceeds the permissible level within any of the first four noise-limit categories, the allowable noise exposure standard shall be increased in 5 decibel increments in each category, as appropriate, to encompass the ambient noise level. In the event the ambient noise level exceeds the fifth noise-limit category, the maximum allowable noise level under said category shall be increased to reflect the maximum ambient noise level.
dBA = A-weighted decibel; Lmax = maximum noise level; LXX = noise level exceeded for a percentage of the time Chapter 9.32 indicates allowable hours for heavy construction activities in Subsection 9.32.050(A) and outdoor carpentry construction in Subsection 9.32.050(B).

Subsection 9.32.050(A) states that:

All operation of power construction equipment or any other construction device that creates noise in excess of the noise level limits of this article, and all performance of any outside construction work, including, but not limited to, grading and trenching, that creates noise in excess of the noise level limits of this article shall be limited to the following hours:
• Monday Through Friday: 7:00 a.m. to 5:30 p.m.
• Saturdays: 8:00 a.m. to 5:00 p.m. with the express written approval of the City engineer or designee.
• Sunday and city holidays: Prohibited.

Subsection 9.32.050(B) states that:

No person in a residential zone shall operate or permit the operation of any mechanically powered saw, sander, drill, grinder, or similar tool that would create noise above the noise level limits of this article, except during the following hours:
• Monday through Friday from 7:00 a.m. until 7:00 p.m.
• Saturday from 9:00 a.m. to 5:00 p.m.

No work described in Subsection B may performed on Sunday or any City holiday or on Monday through Saturday outside of the hours specified above, unless all such work is conducted within a completely enclosed structure.

Section 9.32.070 describes noise sources that are exempt from the provisions found in Chapter 9.32.

Applicable exemptions include:
• The emission of sound for the purpose of alerting persons to the existence of an actual emergency; the emission of sound in the performance of emergency work shall not be subject to the provisions of this article.
• Warning devices necessary for the protection of public safety; for example, police, fire, and ambulance sirens, including the testing of such devices, shall not be subject to the provisions of this chapter.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-73 February 2026 • Activities conducted on public playgrounds and public or private school grounds, including, but not limited to, school athletic and entertainment events, are exempt from the provisions of this article.
• Sounds emanating from regularly scheduled athletic events at city parks. • Construction activity or garbage collection performed by an agency of government, provided that all equipment is operated in accordance with manufacturer's specifications and equipped with all noise-reducing equipment in proper condition. a) Would the project generate a substantial temporary or permanent increase in ambient noise levels in the vicinity of the project in excess of standards established in the local general plan or noise ordinance or applicable standards of other agencies?
Construction
Below are discussions of the equipment and haul- truck noise anticipated to occur during project construction. A summary of the construction schedule and construction activities is provided in Chapter 1,sCEQA Environmental Checklist Form.

Construction Equipment
The analysis of construction noise relies on the equipment noise emission levels developed by FTA (2018). Construction of the project would involve primarily the use of dozers, tractors, and graders.

The construction-period noise level at a given receptor location would depend on the type of construction activity as well as the distance and shielding between the activity and the noisesensitive receptor. Potential noise levels resulting from construction of the project were evaluated by combining the noise levels of the two loudest pieces of equipment that could operate at the same time to characterize a worst-case operating condition. The worst-case operating condition would include simultaneous use of a grader (81 dBA Leq) and a tractor (80 dBA Leq), the two loudest pieces of equipment that could be operated simultaneously during the grading and paving phases of the project. This could result in a combined noise level of 84 dBA Leq at a distance of 50 feet (assuming no intervening topography or structures). The lower end of noise generation would be 74 dBA Leq at a reference distance of 50 feet.

Based on FTA's general assessment methodology for residences, impacts would occur if equipment noise levels were to exceed 90 dBA, 1-hour Leq, during daytime hours (7:00 a.m. to 10:00 p.m.) or 80 dBA, 1-hour Leq, during nighttime hours (10:00 p.m. to 7:00 a.m.). At the nearest receptors, the multi-family residences at the Coppergate Apartments, located 60 feet from the project site, construction noise levels could be up to 82 dBA, 1-hour Leq. As such, construction noise is not expected to exceed the FTA daytime standard of 90 dBA, 1-hour Leq, at any sensitive receptors surrounding the site. However, when the construction noise level is compared to the measured ambient noise levels shown in Table 2-11, construction noise is anticipated to exceed the measured Leq noise levels by up to 21 dBA. However, noise from construction of the project would be temporary and intermittent and would cease once construction is complete.

Regarding construction noise levels at the Goddard School of Brentwood, construction would most likely coincide with school hours. Construction noise levels could be up to 75 dBA, 1-hour Leq, at this location. Noise during construction would be up to 14 dBA above ambient levels at the front façade of the school under worst-case conditions. Although construction noise may be intermittently noticeable outside of the school building, worst-case conditions would generally be limited to the grading and paving phases of the project. The school building would attenuate noise within interior

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-74 February 2026 spaces; therefore, construction noise would not interfere with classroom activities. However, construction noise may be more noticeable in some situations (e.g., when windows are open).

Project construction would occur within the allowable hours outlined in Policy HS-P14.7 of the County General Plan (i.e., between 7:30 a.m. to 5:00 p.m. Monday through Friday). Nighttime work is not anticipated. Construction would result in an increase in noise levels of up to 21 dBA above ambient noise levels; however, noise from construction would be temporary and intermittent and would cease once construction is complete. Best practices for noise control during construction, such as the examples listed in Action N 1e of the City General Plan, would be implemented to minimize noise levels in the community during construction. Therefore, the project would have a less-than-significant impact.

Construction Haul Trucks
Haul and vendor trucks would be used for mobilization and demobilization of construction equipment and materials. The trucks would access northbound and southbound SR 4 via Sand Creek Road. On a worst-case day, project construction would require up to 12 one-way truck trips (e.g., during grading).

Modeling was conducted using the traffic noise levels found in the data tables developed from the Federal Highway Administration (FHWA) Traffic Noise Model (TNM), version 2.5, to estimate average-daily-traffic (ADT) noise levels from haul trucks. A comparison of noise between measured ambient noise levels and combined ambient levels with haul trucks was used to determine if haul-truck noise would exceed the criteria outlined in both County General Plan Policy HS-P14.5 and City General Plan Policy N1-7, as shown in Table 2-13. Refer to Attachment D for complete haul-truck noise modeling inputs and outputs.

Table 2-13. Comparison of Ambient and Ambient-with-Haul-Truck Noise Levels Roadway
Truck Trips
on Segment
(per day)
Modeled
Distance
Measured
Ambient (dBA
Ldn)
Combined
Ambient with
Modeled Haul
Trucks (dBA Ldn)
Change in
dBA Ldn
Sand Creek Road 12 50 63.4a 63.6 0.2
Brentwood Boulevard 12 50 62.2b 62.7 0.5
Business Center Drive 12 50 63.4a 63.6 0.2
Technology Way 12 50 63.4a 63.6 0.2
a. Measurement location LT-2 is representative of this roadway segment. b. Measurement location LT-3 is representative of this roadway segment.

According to modeling, the increase in noise levels due to haul-truck activity is not anticipated to exceed the City standard of 3 dB along roadways adjacent to the project site. The greatest increase in noise from hauling activity was estimated to be 0.5 dB. Project haul-truck activity would result in less than a 3 dB increase in traffic noise. Therefore, the project would have a less-than-significant impact.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-75 February 2026 Operational
Operational Equipment Noise
The proposed building would include a hybrid geothermal heating, ventilation, and air-conditioning (HVAC) system, which would produce noise. This equipment would be located on the rooftop and on the ground level. On the rooftop, the proposed project would include one air-source heat pump. At ground level, there would be a ground-source heat pump and a new electrical transformer. This analysis conservatively assumes that the equipment would run continuously for 1 full hour, effectively making L50 and Leq comparable.

At a distance of 50 feet, a heat pump could produce a sound level of 77 dBA (FTA 2018). Although the precise placement of the rooftop equipment is not known at this time, this analysis conservatively assumes that the project would locate it at the nearest position to a sensitive receptor. With respect to ground-level equipment, the heat pump and transformer would be located west of the proposed building. As previously noted, a heat pump could produce a noise level of 77 dBA at a distance of 50 feet. Noise levels from an electrical transformer were measured at the Streamview Substation in San Diego, California, on November 22, 2019, over 1 minute at a distance of 17 feet. At that distance, measured transformer noise was approximately 66 dBA Leq (or 56 dBA at a normalized distance of 50 feet). Due to the proximity of the equipment, a combined noise level for both pieces of equipment was calculated. The ground-level pump would be located inside a pumphouse structure, which is assumed to result in at least 10 dB of noise reduction (Hoover & Keith 2000). At a distance of 50 feet, combined noise from ground-level equipment is anticipated to be approximately 68 dBA. Tables 2-14 and 2-15 show equipment noise levels from rooftop and ground-level equipment at the nearest receptors, respectively.

Table 2-14 shows that predicted rooftop equipment noise levels would be approximately 1 dB louder than measured daytime noise levels and approximately 8 dB louder than measured nighttime noise levels at the nearest receptors. With respect to ground-level equipment noise, Table 2-15 shows that predicted noise levels are anticipated to be below measured ambient noise levels during daytime and nighttime hours. The results in Tables 2-14 and 2-15 show that existing ambient noise levels in some locations exceed the applicable thresholds. Tables 2-14 and 2-15 also show that rooftop and combined ground-level equipment noise levels are predicted to exceed applicable County and City noise standards at the nearest sensitive receptors.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-76 February 2026 Table 2-14. Predicted Rooftop Equipment Noise Levels at the Nearest Sensitive Receptors Rooftop Equipmenta
Noise level at 50 feet – 77 dBA Leq
Increase
over
Daytime
(Nighttime)
Ambient
Exceed
County
Daytime
Standard?b
Exceed
County
Nighttime
Standard?c
Exceed City
Daytime
Standard?d
Exceed City
Nighttime
Standard?e
Sensitive
Receptor
Distance to
Receptor
Predicted
Noise Level
at Receptor
dBA Leq
Average
Daytime
Ambient
Noise Level
dBA Leq
Average
Nighttime
Ambient
Noise Level
dBA Leq
Goddard
School of
Brentwood
240 63 61.9f 55.4f 1.1
(7.6) Yes N/Ai Yes N/Ai
Silvergate
Apartments
and
Coppergate
Apartments
310 61 61.9f 54.4g -0.9
(6.6) Yes Yes Yes Yes
SingleFamily
Residents to
South
400 59 62.1g 54.4g -3.1
(4.6) No Yes Yes Yes
Hampton
Inn
Brentwood
480 57 60.6h 54.7h -3.6
(2.3) No Yes Yes Yes
Notes: This analysis conservatively assumes that equipment would operate continuously, effectively making L50 and Leq comparable. Therefore, Leq noise levels are shown in this table and considered acceptable for comparing to the County L50 threshold. In addition, distance noise attenuation assumes hard ground conditions, or 6 dB per doubling of distance.
a. Rooftop equipment includes an air-source heat pump
b. The Contra Costa County daytime noise standard used in assessing stationary equipment noise for this analysis is 60 dBA L50. c. The Contra Costa County nighttime noise standard used in assessing stationary equipment noise for this analysis is 55 dBA L50. d. The City of Brentwood noise standard used in assessing stationary equipment noise for this analysis is 55 dBA Leq. e. The City of Brentwood nighttime noise standard used in assessing stationary equipment noise for this analysis is 45 dBA Leq. f. Average daytime and nighttime noise levels are based on the closest and most conservative (lowest) measured ambient noise levels. In this case, LT-2 was used. g. Average daytime and nighttime noise levels are based on the closest and most conservative (lowest) measured ambient noise levels. In this case, LT-1 was used. h. Average daytime and nighttime noise levels are based on the closest and most conservative (lowest) measured ambient noise levels. In this case, LT-3 was used. i. Nighttime noise standards do not apply to the Goddard School of Brentwood because the school would not be open during nighttime hours.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-77 February 2026 Table 2-15. Predicted Ground-Level Equipment Noise Levels at the Nearest Sensitive Receptors Ground-Level Equipmenta
Noise level at 50 feet – 68 dBA Leq
Increase
over
Daytime
(Nighttime)
Ambient
Exceed
County
Daytime
Standard?b
Exceed
County
Nighttime
Standard?c
Exceed City
Daytime
Standard?d
Exceed City
Nighttime
Standard?e
Sensitive
Receptor
Distance to
Receptor
Noise Level
at Receptor
dBA Leq
Average
Daytime
Ambient
Noise Level
dBA Leq
Average
Nighttime
Ambient
Noise Level
dBA Leq
Goddard
School of
Brentwood
270 53 61.9f 55.4f -8.9
(-2.4) No N/Ai No N/Ai
Silvergate
Apartments
and
Coppergate
Apartments
270 53 61.9f 54.4g -8.9
(-2.4) No No No Yes
SingleFamily
Residents to
South
380 50 62.1g 54.4g -12.1
(-4.4) No No No Yes
Hampton
Inn
Brentwood
765 44 60.6h 54.7h -16.6
(-10.7) No No No No
Notes: This analysis conservatively assumes that equipment would operate continuously, effectively making L50 and Leq comparable. Therefore, Leq noise levels are shown in this table and considered acceptable for comparing to the County L50 threshold. In addition, distance noise attenuation assumes hard ground conditions, or 6 dB per doubling of distance.
a. Ground-level equipment includes a ground-source heat pump and an electrical transformer in proximity to one another. b. The Contra Costa County daytime noise standard used in assessing stationary equipment noise for this analysis is 60 dBA L50. c. The Contra Costa County nighttime noise standard used in assessing stationary equipment noise for this analysis is 55 dBA L50. d. The City of Brentwood noise standard used in assessing stationary equipment noise for this analysis is 55 dBA Leq. e. The City of Brentwood nighttime noise standard used in assessing stationary equipment noise for this analysis is 45 dBA Leq. f. Average daytime and nighttime noise levels are based on the closest and most conservative (lowest) measured ambient noise levels. In this case, LT-2 was used. g. Average daytime and nighttime noise levels are based on the closest and most conservative (lowest) measured ambient noise levels. In this case, LT-1 was used. h. Average daytime and nighttime noise levels are based on the closest and most conservative (lowest) measured ambient noise levels. In this case, LT-3 was used.

I. Nighttime noise standards do not apply to the Goddard School of Brentwood because the school would not be open during nighttime hours.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-78 February 2026 In addition to HVAC equipment, the project would also include a battery back-up system, which would be located in the vehicle parking area south of the proposed building, along the southern perimeter of the project site. The dominant noise source associated with each battery back-up system would be the climate control system, with an estimated noise level of approximately 55 dBA at a distance of 50 feet, based on reference data for an industrial air conditioner that would be compatible with a modular battery back-up system enclosure (Marvair 2011). The closest sensitive receivers to the battery back-up system are the single-family homes south of the project site, approximately 475 feet away. At that distance, battery back-up system noise levels would be reduced to approximately 35 dBA. This is below the County daytime and nighttime exterior noise standards of 65 and 55 dBA L50, respectively. In addition, this would be below the exterior noise standards outlined in Policy N1-13 of the City General Plan. Compared to existing ambient noise, noise from the battery back-up system is anticipated to be at least 26 dB below existing daytime ambient noise levels and 20 dBA below existing ambient nighttime noise levels.

Operation of HVAC equipment could exceed exterior noise standards identified in the County Code of Ordinances and Policy N1-13 of the City General Plan, resulting in a potentially significant impact.

Mitigation Measure NOI-1, below, requires building equipment and enclosures to meet County and City noise standards. Therefore, the project would have a less-than-significant impact with mitigation incorporated.

Mitigation Measure NOI-1 Design Building Equipment and Enclosures to Meet County and City Noise Standards
Prior to issuance of building permits for a proposed project building that would include mechanical equipment, the County will retain a qualified acoustical consultant to prepare an acoustical report and address mechanical equipment noise issues, based on the selected equipment models and design features. The final report, including the analysis results and any recommended noise control measures, will be provided to and approved by the County at the time of construction permit application for the building. The recommendations of the report will be incorporated into the applicable project plans (e.g., site, architectural, civil, mechanical, as needed) and implemented during project construction. The acoustical report will satisfy the following requirements:
 The analysis will evaluate the design and provide recommendations, as necessary, to ensure that combined noise levels from mechanical equipment at the project building, including the recommended noise-control measures incorporated into the project design, will not exceed the following noise exposure levels:
 County noise exposure limits (i.e., 60 dBA L50 during daytime hours of 7:00 a.m. to 7:00 p.m. and 55 dBA L50 during nighttime hours of 7:00 p.m. to 7:00 a.m.) for the nearby residential uses; and
 City noise exposure limits (i.e., 55 dBA Leq during daytime hours of 7:00 a.m. to 10:00 p.m. and 45 dBA Leq during nighttime hours of 10:00 p.m. to 7:00 a.m.) for the nearby residential uses.
 The analysis will consider all noise-generating equipment, including the anticipated worstcase combination(s) of equipment that could run simultaneously. Noise-generating equipment may include, but is not limited to, ground-source heat pumps, air-source heat pumps, transformers, and battery back-up system units.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-79 February 2026  Noise-control recommendations may include, but are not limited to, the following:
 Changing equipment locations, including locating equipment inside buildings, as feasible,
 Selecting quieter equipment models,
 Providing equipment sound power limits in procurement specifications,  Shielding equipment with rooftop parapet walls, louvers, screens, or enclosures,  Using acoustic absorption materials, and
 Installing intake or exhaust silencers.

Traffic Noise
Project-specific traffic data, including ADT volumes, roadway speeds, and vehicle mix percentages (i.e., the proportion of automobiles, trucks, buses, and other vehicles), were provided by TJKM. ADT noise levels were modeled using the FHWA TNM under four scenarios: 2018 no project (NP), 2018 with project (WP), 2040 NP, and 2040 WP.14 Refer to Attachment D for complete traffic noise modeling inputs and outputs.

Based on the measured ambient noise levels shown in Table 2-11 and the criteria outlined in Policy HS-P14.5 of the County General Plan and Policy N1-7 of the City General Plan, a significant impact would occur should traffic noise increases between 2018 NP and 2018 WP exceed 3 dB. Traffic noise levels under 2018 NP and 2018 WP conditions are shown in Table 2-16.

Table 2-16. 2018 No-Project and 2018 with-Project Noise Levels Roadway
Modeled
Distance
Modeled 2018 NP Noise
Level (dBA Ldn)
Modeled 2018 WP
Noise Level (dBA Ldn)
Change in
dBA Ldn
Sand Creek Road 50 62.6a 63.8 1.2
Brentwood Boulevard 50 69 69.8 0.8
Business Center Drive 50 62.6a 62.8 0.2
Technology Way 50 62.6a 62.8 0.2
Notes:
2018 NP = 2018 no project; 2018 WP = 2018 with project
a. Measured ambient noise levels (LT-3) were conservatively used to represent this modeling condition.

The results in Table 2-16 indicate that traffic noise due to operation of the proposed project would not result in an increase greater than 3 dB along any of the analyzed roadways. The greatest increase in noise was modeled to be 1.2 dB. Operational traffic noise would not result in an increase of more than 3 dB compared with existing conditions. Therefore, the project would have a less-than-significant impact.

Play-Area Noise
A play area is proposed on the east side of the project building. Noise measurements collected at Linda Vista Elementary School in San Diego were used to estimate noise levels from play areas. At that site, an average level of 64 dBA Leq was measured at 120 feet. Adjusting for distance, the noise 14 As discussed in the traffic impact study prepared for the project (refer to Attachment E), baseline conditions from 2018 were used in the latest Contra Costa Transportation Authority Travel Demand Model.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-80 February 2026 level from the play area at the nearest sensitive receptor would be 50 dBA Leq. This would be below the daytime noise threshold of significance identified in Policy N1-13 of the City General Plan (55 dBA Leq) and below the County exterior noise standard for stationary sources (60 dBA L50). During daytime hours, play-area noise would be occasionally noticeable but below ambient noise levels. Therefore, the project would have a less-than-significant impact. b) Would the project generate excessive groundborne vibration or groundborne noise levels? Construction Vibration
The use of heavy equipment could result in perceptible levels of groundborne vibration in a very localized area around the construction equipment used at the site. Construction of the project would not require the use of high-impact equipment such as a pile driver. A vibratory roller (PPV of 0.210 inch per second, or 94 VdB, at 25 feet) (FTA 2018) was identified as the piece of equipment that could produce the highest vibration levels during project construction. Refer to Attachment D for complete construction vibration modeling inputs and outputs.

The nearest off-site structures that could be exposed to construction-related vibration damage are the Jack in the Box restaurant and the Silvergate Apartments recreational clubhouse. Jack in the Box is approximately 20 feet north of the “Future Development Opportunity” area identified in Figure 2 and conservatively assumed to be reinforced concrete, steel, or timber (no plaster), which has an FTA damage criterion of 102 VdB (FTA 2018). Note that the “Future Development Opportunity” area is not a part of the proposed project. Development would not occur in that area.

However, this analysis conservatively assumes that equipment, including a vibratory roller, could be as close as 20 feet from the Jack in the Box structure. At 20 feet, a vibratory roller is estimated to produce a vibration level of 97 VdB. The use of a vibratory roller within 20 feet of the restaurant would not exceed the FTA damage criterion for reinforced-concrete, steel, or timber (no plaster) structures.

The Silvergate Apartments recreational facility is approximately 45 feet west of the project site.

This structure would be considered a non-engineered timber and masonry building, which has a damage threshold of 94 VdB. At a distance of 45 feet, vibration levels from a vibratory roller are estimated to be 86 VdB. Estimated vibration levels at the structure would be below the damage threshold for the type of building. It is anticipated that structures located farther away, such as the Coppergate Apartments, which are about 60 feet from the project site, would be exposed to vibration levels that would be even lower.

With respect to vibration-related annoyance, the nearest residential sensitive receptor, the Coppergate Apartments, is approximately 60 feet to the west. At a distance of 60 feet, vibration levels from a vibratory roller are estimated to be 83 VdB. At a distance of 130 feet, vibration from a vibratory roller is estimated to be 73 VdB. At both the Coppergate Apartments and the Goddard School of Brentwood, worst-case vibration levels would be below the FTA vibration threshold for “readily perceptible” vibration. At greater distances, vibration levels would be reduced and would remain below the FTA threshold for “readily perceptible” vibration.

Given the analysis described above, vibration-intensive construction equipment is not anticipated to cause structural damage at the nearest off-site structures. In addition, groundborne vibration during construction is not expected to result in a negative community reaction. Therefore, the project would have a less-than-significant impact.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-81 February 2026 Operational Vibration
Operation of the project would not involve sources that would generate a noticeable level of vibration. Therefore, the project would have a less-than-significant impact. 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 2 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? The closest airports to the project site are Funny Farm Airport, a privately owned airport approximately 2.7 miles east of the project site in the city of Brentwood, and Byron Airport, a public airport approximately 8.2 miles southeast of the project site in Byron. Because the project site is more than 2 miles from the nearest airfields, an exposure to excessive aircraft noise at the project site would not occur. Furthermore, the proposed project would not introduce any new aircraft noise sources and would not result in changes to flight operations at any existing airports, airfields, airstrips, or heliports in the region. Therefore, the project would have no impact.

2.13.2 Sources of Information
City of Brentwood. 2014. City of Brentwood General Plan. July. Available:
https://www.brentwoodca.gov/home/showpublisheddocument/2900/6383010446565000

00. Accessed: May 1, 2025.

Contra Costa County. 2024. Envision Contra Costa County 2045 General Plan. November.

Available: https://www.contracosta.ca.gov/DocumentCenter/View/84957/Contra-CostaCounty-2045-General-Plan-PDF---Large-file-782-MB. Accessed: December 26, 2025.

Federal Transit Administration. 2018. Transit Noise and Vibration Impact Assessment Manual.

FTA Report No. 0123. Available:
https://www.transit.dot.gov/sites/fta.dot.gov/files/docs/researchinnovation/118131/transit-noise-and-vibration-impact-assessment-manual-fta-report-no0123_0.pdf. Accessed: May 6, 2025.

Hoover & Keith. 2000. Noise Control for Buildings, Manufacturing Plants, Equipment, and Products.

Houston, TX.

Marvair. 2011. AVPA – Outdoor Sound Data. March.

2.14 Population and Housing
Potentially
Significant
Impact
Less than
Significant with
Mitigation
Incorporated
Less-thanSignificant
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)?
ISi

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-82 February 2026 Potentially
Significant
Impact
Less than
Significant with
Mitigation
Incorporated
Less-thanSignificant
Impact No Impact
Would the project:
b) Displace substantial numbers of existing people or housing, necessitating the construction of replacement housing
elsewhere?

2.14.1 Discussion
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)?
The project would not include new homes or businesses that could directly induce population growth. It is anticipated that visitors to the proposed service center would be existing residents in the project area; they would not move to the region due to the proposed project. However, the proposed project would result in approximately 441 County employees working at the project site, including approximately 150 relocated employees from other County facilities. The increase in employment compared to existing employment conditions could result in new demand for additional housing within commuting distance. According to the environmental impact report (EIR) prepared for the City General Plan, buildout of non-residential uses within the city may increase employment opportunities and require approximately 21,232 employees (City of Brentwood 2014).

Therefore, the 291 employees generated by the proposed project (i.e., those who would not relocate from other County facilities) would equal approximately 1 percent of anticipated employment growth in the city. The number of employees generated by the proposed project would not exceed the City’s projections. Furthermore, no infrastructure is proposed that could indirectly induce population growth. Therefore, the project would have a less-than-significant impact. b) Displace substantial numbers of existing people or housing, necessitating the construction of replacement housing elsewhere?
The project site is currently vacant. The project would not displace any existing housing; as such, replacement housing would not be necessary. Therefore, the project would have no impact.

2.14.2 Sources of Information
City of Brentwood. 2014. Brentwood General Plan Environmental Impact Report. April. Available:
https://www.brentwoodca.gov/home/showpublisheddocument/2832/637794835332370000.

Accessed: August 1, 2025.
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Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-83 February 2026

2.15 Public Services
Potentially
Significant
Impact
Less than
Significant with
Mitigation
Incorporated
Less-thanSignificant
Impact No Impact
Would the project:
a) Result in substantial adverse physical impacts associated with the provision of new or physically altered governmental facilities or the 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 following public
services:

Fire protection?
Police protection?
Schools?
Parks?
Other public facilities?

2.15.1 Discussion
The following analysis addresses the proposed project’s potential impacts related to fire protection, police protection, schools, parks, and other public services. Impacts related to public services would occur if the proposed project were to increase demand for services and require new or expanded facilities that cause environmental impacts.
a) Would the project result in substantial adverse physical impacts associated with the provision of new or physically altered governmental facilities or the 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 following public services:

Fire protection?
Fire protection services for the project site are provided by the Contra Costa County Fire Protection District. The fire station closest to the project site is Fire Station No. 92 at 201 John Muir Parkway in the city. The proposed project would not include any residential uses. However, it would result in approximately 441 County employees working at the project site, including approximately 150 relocated employees from other County facilities. In addition, there would be visitors at the proposed service center. Thus, the proposed project would substantially increase the daytime population on the project site compared to existing conditions, which could result in increased demand for fire services. However, the Contra Costa County Fire Protection District would continue to provide services to the project site. Because the proposed project would be located in an urbanized area of the city, it is not anticipated that additional firefighters would be required to serve the proposed project. Therefore, construction of a new or expanded fire station would not be required. In addition, the proposed project would be required to comply with all applicable codes regarding fire safety and emergency access. Given the above, the proposed project would not result in a significant impact on the physical environment due to the incremental increase in demand for fire protection. Therefore, the project would have a less-than-significant impact.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-84 February 2026 Police protection?
Police protection services for the project site are provided by the Brentwood Police Department. The police station closest to the project site is at 9100 Brentwood Boulevard in the city. As noted in the discussion above regarding fire protection, the employees and visitors generated by the project would substantially increase the daytime population on the project site compared to existing conditions; this could result in increased demand for police protection. However, the Brentwood Police Department would continue to provide services to the project site. Because the proposed project would be located in an urbanized area of the city, and because it would not be expected to attract crime or be a source of crime, it is not anticipated that additional sworn officers would be required to serve the proposed project. The construction of a new or expanded police station would not be required. In addition, an approximately 8-foot-tall fence would be installed around the perimeter of the staff and fleet vehicle parking areas as well as at the north and east ends of the building, which would further deter crime.

Given the above, the proposed project would not result in a significant impact on the physical environment due to the incremental increase in demand for police protection. Therefore, the project would have a less-than-significant impact.

Schools?
The Brentwood Union School District (K–5 elementary schools and 6–8 middle schools) and Liberty Union High School District (9–12 high schools) serve the project site. The proposed project would not include any residential uses and would not directly generate any school-age children. However, the proposed project would result in approximately 441 County employees working at the project site, including approximately 150 relocated employees from other County facilities. The increase in employment compared to existing employment conditions could indirectly generate school-age children. It is not anticipated that construction of a new or expanded school as a result of the proposed project would be required to accommodate the school-age children generated by project employees.

Given the above, the proposed project would not result in a significant impact on the physical environment due to the incremental increase in the number of school-age children. Therefore, the project would have a less-than-significant impact.

Parks?
According to the EIR prepared for the City General Plan, the city has approximately 207 acres of developed parkland, 61 parks and facilities, and 16 miles of multi-use trails (City of Brentwood 2014).

The parks closest to the project site are Sparrow Park, to the north, and Sycamore Park, to the east, both of which are 0.6 mile from the project site. As noted in the discussion above regarding fire protection, the employees and visitors generated by the project would substantially increase the daytime population on the project site compared to existing conditions; this could result in increased use of nearby parks. However, the increase in park usage would be minor. The construction of a new or expanded parks would not be required. In addition, the proposed project would include a secure play area on-site for children, which could offset the minor increase in demand for park services. Given the above, the proposed project would not result in a significant impact on the physical environment due to the incremental increase in demand for parks. Therefore, the project would have a less-thansignificant impact.

Other Public Facilities?
Library services for the project site are provided by the Brentwood Library, which is part of the Contra Costa County Library System. The Brentwood Library, at 104 Oak Street, is the only public library in the

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-85 February 2026 city. As noted in the discussion above regarding fire protection, the employees and visitors generated by the project would substantially increase the daytime population on the project site compared to existing conditions; this could result in increased demand for library services. However, the increase in library usage would be minor. The Brentwood Library would continue to provide services for the project site.

The construction of a new or expanded library would not be required. Given the above, the proposed project would not result in a significant impact on the physical environment due to the incremental increase in demand for libraries. Therefore, the project would have a less-than-significant impact.

2.15.2 Sources of Information
City of Brentwood. 2014. Brentwood General Plan Environmental Impact Report. April. Available:
https://www.brentwoodca.gov/home/showpublisheddocument/2832/637794835332370000.

Accessed: August 1, 2025.

2.16 Recreation
Potentially
Significant
Impact
Less than
Significant with
Mitigation
Incorporated
Less-thanSignificant
Impact No Impact
Would the project:
a) Increase the use of existing neighborhood and regional parks or other recreational facilities such that substantial physical deterioration of the facilities would occur or be accelerated? b) Include recreational facilities or require the construction or expansion of recreational facilities, which might have an adverse physical effect on the environment?

2.16.1 Discussion
a) Would the project increase the use of existing neighborhood and regional parks or other recreational facilities such that substantial physical deterioration of the facilities would occur or be accelerated? Refer to Section 2.15, Public Services, for a discussion of the parks and recreational facilities in the city and the potential impacts of project related to park facilities. The minor increase in park usage due to the project employees and visitors is not anticipated to result in the deterioration of parks and recreational facilities in the vicinity of the site, including Sparrow Park and Sycamore Park. In addition, there is a sufficient number and variety of open space and recreational opportunities within the project area to accommodate the project employees and visitors. Therefore, the project would have a lessthan-significant impact. b) Would the project include recreational facilities or require the construction or expansion of recreational facilities, which might have an adverse physical effect on the environment? The proposed project would include an on-site secure child play area and a trellis or gazebo for outdoor functions. The physical effects of these proposed recreational facilities are evaluated under the applicable resource topics in this initial study, such as in Section 2.3, Air Quality; Section 2.8, Greenhouse Gas Emissions; and Section 2.13, Noise. The proposed project has the potential to incrementally increase the use of nearby parks and recreational facilities, particularly Sparrow Park and Sycamore Park. However, the minor increase in use generated by the proposed project is not

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-86 February 2026 anticipated to require the construction or expansion of recreational facilities. Therefore, the project would have a less-than-significant impact.

2.17 Transportation
Potentially
Significant
Impact
Less than
Significant with
Mitigation
Incorporated
Less-thanSignificant
Impact No Impact
Would the project:
a) Conflict with a program plan, ordinance, or policy addressing the circulation system, including transit, roadways, bicycle, and pedestrian facilities?
b) Conflict with or be inconsistent with State 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?

2.17.1 Discussion
A traffic impact study for the project was prepared by TJKM (TJKM 2025) (refer to Attachment E). a) Would the project conflict with a program, plan, ordinance, or policy addressing the circulation system, including transit, roadway, bicycle, and pedestrian facilities? The project site is owned by the County and is in the city of Brentwood. The following policies from the County General Plan apply to the proposed project (County 2024):
• Policy GM-P2.3: Apply CCTA’s [Contra Costa Transportation Authority’s] travel demand forecasting model and technical procedures to the analysis of general plan amendments affecting land use or circulation and development projects that generate more than 100 peakhour trips to determine their effects on the regional transportation system and compliance with the applicable Action Plan Multimodal Transportation Service Objectives/Regional Transportation Objectives.
• Policy GM-P2.4: Circulate traffic impact analyses to affected jurisdictions and the RTPCs [regional transportation planning councils] for review and comment and cooperate in assessment and mitigation of traffic impacts in neighboring jurisdictions resulting from County actions.

Operation of the proposed project would have the potential to generate 100 or more morning (AM) or evening (PM) peak-hour trips. The traffic impact study prepared for the proposed project was prepared in accordance with the applicable County General Plan policies identified above.

Circulation System Performance (Level of Service/Queuing) To evaluate impacts on the transportation system due to the addition of traffic from the proposed project, the traffic impact study evaluated four study intersections and four access points during the weekday AM peak hour and weekday PM peak hour under four study scenarios (existing, existing- □
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Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-87 February 2026 plus-project, background, and background-plus-project conditions).15 The project’s average daily traffic would be approximately 3,285 during a typical weekday, with 538 AM peak-hour trips (403 in/135 out) and 401 PM peak-hour trips (172 in/229 out). All intersections would operate at an acceptable level of service under all scenarios during both peak hours.

An intersection queueing analysis was conducted for the same four scenarios referenced above.

Under the comparison of existing and existing-plus-project conditions, three of the 95th percentile queueing results exceeded available storage capacities. The observed spillbacks ranged from less than one to two vehicle lengths; spillbacks would be resolved through the following project features:
• Brentwood Boulevard at Technology Way – Northbound Left-Turn Movement (NB-L): The existing raised median would be modified to allow the extension of the turn pocket and increase the storage capacity.
• Brentwood Boulevard at Sand Creek Road – Eastbound Right-Turn Movement (EB-R): Modify roadway painting to use the existing available spacing between the turn pocket’s western terminus and the eastern limit of an existing driveway 30 feet west of the western terminus of the turn pocket.
• Business Center Drive at Sand Creek Road – Eastbound Left-Turn Movement (EB-L): Modify the existing raised median to allow the extension of the turn pocket and increase the storage capacity.

Modifications (e.g., modifications to access points or the circulation system) within the public rightof-way would be constructed to comply with City standards. Given the above, the proposed project would not change operations at the intersections in the vicinity of the project site or impede access to and from the site. Therefore, the project would have a less-than-significant impact.

Internal Circulation
Internal vehicle circulation within the site would be separated into three areas, consisting of one area for public parking, one area for County staff-only parking, and one drop-off zone. Internal circulation would be provided by two-way vehicle pathways that would connect public parking areas on the north side of the project site to those on the east side of the project site. Internal circulation for staff-only parking areas would be provided by two-way vehicle pathways running from the west side of the project site to the south side of the project site. Pedestrian and bicycle circulation throughout the site would be facilitated by a series of new pedestrian pathways, connecting pedestrians walking to and from planned project buildings and parking areas to the existing sidewalks fronting the project site (along Brentwood Boulevard, Technology Way, and Business Center Drive). By using Technology Way for two of the access points, the project would minimize roadway disturbance along Brentwood Boulevard and Business Center Drive. The internal circulation pattern of the project would not conflict with any applicable program, plan, ordinance, or policy related to roadways. Therefore, the project would have a less-than-significant impact. 15 TJKM used the published trip generation rates from the Institute of Transportation Engineers (ITE) Trip Generation Manual, 11th edition, consistent with the methodology published in ITE’s Trip Generation Handbook, third edition. For a conservative approach, the land use intensity selected had the higher average trip generation rate of the two intensities considered, resulting in a higher trip generation estimate. Table 5 in the traffic impact study provides the project’s trip generation estimate.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-88 February 2026 Transit
The project site is in an area with several bus stops that connect users to various bus routes serviced by Tri Delta Transit. Three bus routes have been identified that provide service to four bus stops within a 0.25-mile walk from the project site. The existing transit facilities within the project vicinity have weekday service, with headways between 20 and 60 minutes; on weekends, headways are approximately 60 minutes. It is anticipated that most employees would drive to the project site.

Therefore, local transit vehicle capacities are not expected to be exceeded. It is unlikely that the project would generate a large demand for the transit services and facilities that serve the area. The project is not expected to conflict with existing or planned transit facilities. Therefore, the project would have a less-than-significant impact.

Bicycle
The project site is in an area with ample bicycle infrastructure, including Class I bike paths (e.g., Marsh Creek Trail and Barrington Trail) and Class II bike lanes. In addition, the project would include bicycle infrastructure on-site, including bicycle parking areas for County staff members and the public, that would support and promote the use of bicycles. Therefore, the project would have a less-than-significant impact.

Pedestrian
The project site is in an area with ample pedestrian infrastructure and connectivity to off-site locations along the studied roadways. Identified pedestrian infrastructure includes marked pedestrian crosswalks, pedestrian push buttons at signalized locations, pedestrian countdown heads, and truncated domes. The project would include internal pathways that would connect pedestrians to the existing public pedestrian infrastructure along the streets fronting the project site. Therefore, the project would have a less-than-significant impact.

Parking
The project would provide 424 vehicle parking spaces in surface-level parking areas. Bicycle parking would also be provided, with capacity for approximately 58 bicycles (22 long-term spaces and 36 short-term spaces). As a development project involving a new government building, consistent with the findings referenced from the ITE Parking Generation Manual, sixth edition (October 2023), the project’s parking supply would be above minimum parking demand requirements. Therefore, the project would have no impact.

Conclusion
Based on the above, the project would not conflict with a program, plan, ordinance, or policy addressing the circulation system. Therefore, the project would have a less-than-significant impact. b) Would the project conflict with or be inconsistent with State CEQA Guidelines Section 15064.3, subdivision (b)?
State CEQA Guidelines Section 15064.3 refers to an assessment of VMT. The traffic impact study prepared for the proposed project includes a full VMT analysis that follows the Contra Costa Transportation Authority (CCTA) Growth Management Program Implementation Guidelines, Appendix

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-89 February 2026 F, adopted in February 2021 (VMT Guidelines).16 The VMT analysis considered “base year 2018” and “cumulative year 2040” to determine if the project, located in Travel Analysis Zone (TAZ) #30325, would exceed the CCTA VMT threshold. Under the 2018 base-year run, the threshold is identified as

13.50, while total VMT per worker with the project is 7.43. Under the 2040 cumulative-year run, the threshold is 13.41, and the resultant total VMT per worker with the project is 7.51. Because projectgenerated VMT per worker is below the applicable 85 percent threshold of the Bay Area regional average for both run years, the project would be consistent with State CEQA Guidelines Section 15064.3(b). Therefore, the project would have a less-than-significant impact. c) Would the project substantially increase hazards due to a geometric design feature (e g., sharp curves or dangerous intersections) or incompatible uses (e.g., farm equipment)? The proposed access points to the project site would be designed and constructed in compliance with City of Brentwood and Contra Costa County standards regarding geometric design to provide users with adequate sight distance. Project access points would not be obscured by landscaping at corners that would limit sight lines. In addition, the new access points to the project site would not require changes to the existing roadways in the project area. The project would not increase hazards due to a geometric design feature. Therefore, the project would have a less-than-significant impact. d) Would the project result in inadequate emergency access? The project would be designed to meet current City of Brentwood and Contra Costa County requirements for emergency vehicle access and operations. Included would be the provision of adequate emergency vehicle access points and internal circulation spacing as well as pathways to facilitate emergency vehicle operations within the project site. Therefore, the ability of emergency vehicles to access and exit the project site would not be impeded by the project. Therefore, the project would have no impact.

2.17.2 Sources of Information
Contra Costa County. 2024. Contra Costa County 2045 General Plan. Adopted: November 5, 2024.

Available: https://www.contracosta.ca.gov/DocumentCenter/View/84957/Contra-Costa-County2045-General-Plan-PDF---Large-file-782-MB.

TKJM. 2025. Traffic Impact Study, East County Service Center. July 14. Prepared for Contra Costa County. 16 Appendix E to the traffic impact study (refer to Attachment E) includes the full technical memorandum prepared by TJKM describing the project’s VMT analysis.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-90 February 2026

2.18 Tribal Cultural Resources
Potentially
Significant
Impact
Less than
Significant with
Mitigation
Incorporated
Less-thanSignificant
Impact No Impact
Would the project:
a) 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:
i) listed in 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
ii) 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.

2.18.1 Discussion
CEQA states that “[a] project with an effect that may cause a substantial adverse change in the significance of a tribal cultural resource is a project that may have a significant effect on the environment” (Public Resources Code Section 21084.2). In order to be considered a “tribal cultural resource,” a resource must be either:

1. Listed or eligible for listing in the California Register of Historical Resources, or in the local register of historical resources as defined in Public Resources Code Section 5020.1(K) (see Section 2.5.1 for additional information), or

2. 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.

To help determine whether a project may have such an effect, the lead agency must consult with any California Native American tribe that requests consultation and is traditionally and culturally affiliated with the geographic area of a proposed project. If a lead agency determines that a project may cause a substantial adverse change to tribal cultural resources, the lead agency must consider measures to mitigate that impact.

A cultural resources assessment report for the project was prepared by Cogstone (Cogstone Resource Management 2025).

Costa Contra County conducted the tribal consultation for the proposed project. Tribes that previously requested to be notified of projects within Contra Costa County under AB 52 include Wilton Rancheria and Confederated Villages of Lisjan Nation (CVLN). The County conducted □ □ □

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-91 February 2026 outreach to initiate consultation on February 24, 2025. CVLN did not provide information about resources or request consultation but did provide recommendations on avoidance, mitigation, and monitoring measures. Wilton Rancheria requested consultation on February 24, 2025. The County consulted with Wilton Rancheria regarding the methods of resource investigation identification as well as avoidance, mitigation, and monitoring measures. Measures were agreed upon, and consultation was concluded on September 10, 2025.
a) 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:
i) Listed in 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 ii) 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.

Tribal cultural resources were identified during tribal consultation. Due to the proximity of the project to the highly culturally sensitive Marsh Creek, the potential exists for resources that could be considered tribal cultural resources to be uncovered during project construction and subjected to damage, removal, or other such impacts. This would be a potentially significant impact.

Implementation of Mitigation Measures CUL-1 through CUL-5 (refer to Impacts a, b, and c in Section 2.5, Cultural Resources) as well as Mitigation Measures TCR-1 and TCR-2, below, would ensure procedures are followed in the case of a discovery, including working with the Tribes to determine the appropriate course of action. Therefore, the project would have a less-thansignificant impact with mitigation incorporated.

Mitigation Measure CUL-1: Environmentally Sensitive Area and Tribal Monitoring Mitigation Measure CUL-2: Cultural Awareness Training
Mitigation Measure CUL-3: Procedures for Inadvertent Discovery of Unanticipated Historic Resources or Tribal Cultural Resources
Mitigation Measure CUL-4: Communication Protocols for Tribal Monitoring Refer to Impacts a and b in Section 2.5, Cultural Resources.

Mitigation Measure CUL-5: Stop Work and Notification Procedures for Human Remains Refer to Impact c in Section 2.5, Cultural Resources.

Mitigation Measure TCR-1: Collaboration with Local Native American Tribes to Honor the indigenous Community
The project proponents shall work in collaboration with the Wilton Rancheria to determine how to best honor the indigenous community that lived in the area prior to colonization and the proposed California Indian District. This could be expressed through installation of an

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-92 February 2026 information panel or plaque that describes the importance of the area, and incorporation of indigenous art and design elements and native plants into the design for the project, to honor and acknowledge tribal history and ancestry.

Mitigation Measure TCR-2: Support for Tribal Ceremonies to Preserve the Sacred Nature of the Project Site
If requested by Wilton Rancheria, the project proponents shall accommodate ceremonial practices at the project site, to help preserve and restore the sacredness of the significant Tribal cultural resources that will be affected by construction. The nature and the frequency of the ceremonies will be determined by the Wilton Rancheria, but the project proponents understand that such ceremonies will not unnecessarily impede the project. The County shall negotiate the level of reimbursement to the Wilton Rancheria for the cost of the materials necessary for conducting the on-site ceremonies to be held before the start of project construction.

NON-INTENTIONAL DISTURBANCES
Unless authorized by Wilton Rancheria THPO, contractors, subcontractors, or consultants shall not purposely (1) search for, (2) disturb, (3) photograph/draw or (4) excavate Burials, Burial Objects, Burial Soil, Cemeteries, Sacred Objects, or Sacred Sites and Structures beyond the requirements of the project activity. Any unapproved deliberate search, disturbance or excavation shall be considered to be a violation of this agreement and potentially a violation of the California State Public Resources Code as outlined under heading 5.

Such areas or objects may be unintentionally encountered during the course of ground disturbance. If this occurs, work must be stopped in the Work Area for 100 feet in all directions from the disturbance. Work may not resume in this area until it has been authorized by the Wilton Rancheria THPO or his appointee. Such authorization shall not be unreasonably withheld by Wilton Rancheria, and Wilton Rancheria shall provide a plan for work to resume within two business days of unintentional disturbance.

CONFIDENTIALITY
California Public Records Act, California Government Code §§ 6254.10, 6254(r). Records of Native American graves, cemeteries, and sacred places and records of Native American places, features, and objects described in Sections 5097.9 and 5097.993 of the Public Resources Code maintained by, or in the possession of, the Native American Heritage Commission, another state agency, or a local agency.

Nothing in this chapter requires disclosure of records that relate to archaeological site information and reports maintained by, or in the possession of, the Department of Parks and Recreation, the State Historical Resources Commission, the State Lands Commission, the Native American Heritage Commission, another state agency, or a local agency, including the records that the agency obtains through a consultation process between a California Native American tribe and a state or local agency.

The National Historic Preservation Act (NHPA, 54 U.S.C. § 307103), which provides limited authority for withholding disclosure of information about the “location, character and ownership” of historic resources to the public.

The Archaeological Resources Protection Act (ARPA, 16 U.S.C. § 470hh), which provides authority to limit information on the “nature and location” of archaeological resources.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-93 February 2026

2.18.2 Sources of Information
Cogstone Resource Management. 2025. Cultural Resources Assessment Report for the East County Service Center Project. Contra Costa County Project No. WH429A. Prepared for Contra Costa County, City of Brentwood, CA.

2.19 Utilities and Service Systems
Potentially
Significant
Impact
Less than
Significant with
Mitigation
Incorporated
Less-thanSignificant
Impact No Impact
Would the project:
a) Require or result in the relocation or construction of new or expanded water, wastewater treatment (for stormwater
drainage), electric 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 official dry and multiple dry years?
c) Result in a determination by the wastewater treatment provider that 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 statutes and regulations related to solid waste?

2.19.1 Discussion
a) Would the project require or result in the relocation or construction of new or expanded water, wastewater treatment (for stormwater drainage), electric power, natural gas, or telecommunications facilities, the construction or relocation of which could cause significant environmental effects? The project site is within the Contra Costa Water District (CCWD), Delta Diablo, and Pacific Gas & Electric Company (PG&E) service areas. The proposed project would require the construction of new utility services to the project site because the project site is currently undeveloped. The physical effects of the construction of these proposed utility connections, which would require excavation, trenching, soil movement, and other activities typical of construction of development projects in the city, are included in the analysis of the project as a whole under the applicable resource topics in this initial study (e.g., Section 2.3, Air Quality; Section 2.13, Noise; and Section 2.17, Transportation). In addition, modifications (e.g., utility connections, etc.) within the public right-of-way would be constructed in compliance with City standards.

Water
The City owns and operates a water supply and distribution system that supplies potable water to residences and business within the city; the potable water comes from a combination of surface and

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-94 February 2026 groundwater sources (City of Brentwood 2014). The project site is currently vacant and does not generate any demand for water. The proposed project would result in an increase in water demand at the project site compared to existing conditions, which would result in an incremental increase in the water demand within the city. However, the project would be expected to achieve, at a minimum, LEED Silver certification by incorporating water-efficient features (e.g., water efficient plumbing fixtures), which would reduce the project’s water demand. The project site is undeveloped and the proposed project would require the construction of connections to existing water facilities in the vicinity of the project site. As discussed above, the physical effects of the construction of these proposed utility connections are included in the analysis of the project as a whole under the applicable resource topics in this Initial Study (e.g., Section 2.3, Air Quality; Section 2.13, Noise; and Section 2.17, Transportation). Based on the above, it is not anticipated that the proposed project would require the construction or expansion of water treatment facilities. Therefore, the project would have a less-than-significant impact.

Wastewater Treatment
The City of Brentwood Wastewater Treatment Plant is used for the treatment and disposal, or reuse, of wastewater generated within the City’s service area. The project site is currently vacant and does not generate any wastewater. The proposed project would result in an increase in wastewater generation at the project site compared to existing conditions, which would result in an incremental increase in the average daily flow to the City of Brentwood Wastewater Treatment Plant. However, the project would be expected to achieve, at a minimum, LEED Silver certification by incorporating water-efficient features (e.g., water efficient plumbing fixtures), which would reduce the project’s wastewater generation. The project site is undeveloped and the proposed project would require the construction of connections to existing wastewater facilities in the vicinity of the project site. As discussed above, the physical effects of the construction of these proposed utility connections are included in the analysis of the project as a whole under the applicable resource topics in this Initial Study (e.g., Section 2.3, Air Quality; Section 2.13, Noise; and Section 2.17, Transportation). Based on the above, it is not anticipated that the proposed project would require the construction or expansion of wastewater treatment facilities. Therefore, the project would have a less-thansignificant impact.

Stormwater Drainage
As discussed under Impact c in Section 2.10, Hydrology and Water Quality, minor grading would temporarily alter existing drainage patterns during construction. The project site is undeveloped and the proposed project would require the construction of connections to existing stormwater facilities in the vicinity of the project site. As discussed above, the physical effects of the construction of these proposed utility connections are included in the analysis of the project as a whole under the applicable resource topics in this initial study (e.g., Section 2.3, Air Quality; Section 2.13, Noise; and Section 2.17, Transportation). In addition, implementation of the project would result in the addition of impervious surface cover. However, the project would include stormwater treatment basins and landscaping, which would decrease the rate and volume of stormwater runoff prior to discharge into the municipal storm drain. Therefore, the project would have a less-than-significant impact.

Electricity
The project site is within the PG&E service area. PG&E will supply and distribute electric power to the proposed project. The project site is undeveloped and the proposed project would require the

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-95 February 2026 construction of connections to existing electric facilities in the vicinity of the project site. As discussed above, the physical effects of the construction of these proposed utility connections are included in the analysis of the project as a whole under the applicable resource topics in this initial study (e.g., Section 2.3, Air Quality; Section 2.13, Noise; and Section 2.17, Transportation). Therefore, the project would have a less-than-significant impact.

Telecommunications
It is anticipated that telecommunications would be provided by AT&T and potentially Comcast. The project site is undeveloped and the proposed project would require the construction of connections to existing telecommunications facilities in the vicinity of the project site. As discussed above, the physical effects of the construction of these proposed utility connections are included in the analysis of the project as a whole under the applicable resource topics in this initial study (e.g., Section 2.3, Air Quality; Section 2.13, Noise; and Section 2.17, Transportation). Therefore, the project would have a less-than-significant impact.
b) Would the project have sufficient water supplies available to serve the project and reasonably foreseeable future development during official dry and multiple dry years? The City owns and operates a water supply and distribution system that supplies potable water to residences and business within the city; the potable water comes from a combination of surface and groundwater sources (City of Brentwood 2014). The project site is currently vacant and does not generate any demand for water. The proposed project would result in an increase in water demand at the project site compared to existing conditions, which would result in an incremental increase in the water demand within the city. However, the project would be expected to achieve, at a minimum, LEED Silver certification by incorporating water-efficient features (e.g., water efficient plumbing fixtures), which would reduce the project’s water demand. The City of Brentwood 2020 Urban Water Management Plan (UWMP) addresses the City’s water system and includes a description of the service area, water use, water supply sources and reliability, water shortage contingency planning, and water conservation activities (City of Brentwood 2021). The Contra Costa Water District 2020 UWMP addresses the district’s supply and demand forecasts, conservation programs, water demand management measures, and recycled water opportunities through 2045 (Contra Costa Water District 2021). The City expects no reductions in the normal‐year supply during single or multiple dry years and thus does not project water supply shortages in the future. In addition, the CCWD does not anticipate any supply deficits in normal years or single dry years throughout the planning horizon; supply shortfalls of up to 15 percent of demand may occur in future years under multiple dry-year conditions. Any potential supply shortfalls experienced during dry-year conditions will be met through a combination of a short-term conservation program and/or shortterm water purchases, consistent with the CCWD’s future water supply study. Given the above, the proposed project would not require the relocation or construction of new or expanded off-site water facilities (other than the proposed connection to the City’s existing infrastructure in the vicinity of the project site), the construction of which could cause significant environmental effects, and sufficient water supplies would be available to serve the proposed project and reasonably foreseeable development during normal, dry, and multiple dry years. Therefore, the project would have a less-than-significant impact.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-96 February 2026 c) Would the project result in a determination by the wastewater treatment provider that 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?
The City of Brentwood Wastewater Treatment Plant is used for the treatment and disposal, or reuse, of wastewater generated within the City’s service area. The project site is currently vacant and does not generate any wastewater. The proposed project would result in an increase in wastewater generation at the project site compared to existing conditions, which would result in an incremental increase in the average daily flow to the City of Brentwood Wastewater Treatment Plant. However, the proposed project would comply with City General Plan Policy IF 1-2, which requires development, infrastructure, and long-term planning projects to be consistent with all applicable City infrastructure plans, including the Water Master Plan, the Wastewater Master Plan, and the Capital Improvement Program. In addition, the proposed project would comply with City General Plan Policy IF 1-3, which requires all development projects to mitigate their infrastructure service impacts or demonstrate that the City’s infrastructure, public services, and utilities can accommodate the increased demand for services and that service levels for existing users will not be degraded or impaired. Further, the project would be consistent with County General Plan Policy PFS-P4.6, which requires new development to demonstrate the availability of a safe, sanitary, and environmentally sound wastewater treatment system with adequate capacity. The appropriate wastewater treatment approvals/permits would be obtained from the City prior to construction. Therefore, the project would have a less-than-significant impact.
d) Would the project 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? The County would provide garbage, yard waste, and recycling collection services to the project site.

Solid waste would be taken to the Brentwood Solid Waste Transfer Station and then to Keller Canyon Landfill. According to the EIR prepared for the City General Plan, the Solid Waste Transfer Station has a permitted daily capacity of 400 tons and in 2012, it averaged approximately 155 tons per day (City of Brentwood 2014). The Keller Canyon Landfill handles approximately 2,500 tons of waste per day and the permit allows up to 3,500 tons of waste per day. The Keller Canyon Landfill has approximately 63.4 million cubic yards of remaining capacity and the estimated closure date is 2050 (California Department of Resources Recycling and Recovery 2025). The project site is currently vacant and does not generate any solid waste. The proposed project would result in an increase in solid waste generation at the project site compared to existing conditions, which would result in an incremental increase in the amount of solid waste that would be taken to the City’s Solid Waste Transfer Station and then to Keller Canyon Landfill. However, the proposed project would comply with Division 4.4, Material Conservation and Resource Efficiency, of CALGreen, which requires at least 65 percent of nonhazardous construction and demolition waste from nonresidential construction operations to be recycled and/or salvaged for reuse. The project would also comply with the City’s Construction and Demolition Debris Recycling Ordinance, which requires applicable projects to recycle at least 50 percent of their waste stream. In addition, as discussed under Impact e, below, the proposed project would be required to comply with federal, state, and local waste reduction and recycling regulations. Based on the above, the proposed project would be served by a landfill with adequate capacity to serve the proposed project’s solid waste disposal needs. Therefore, the project would have a less-than-significant impact.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-97 February 2026 e) Would the project comply with federal, state, and local management and reduction statutes and regulations related to solid waste?
The proposed project would be required to comply with federal, state, and local waste reduction and recycling regulations, particularly those contained in the California Integrated Waste Management Act (Assembly Bill 939); Division 4.4, Material Conservation and Resource Efficiency, of CALGreen; and the City’s Construction and Demolition Debris Recycling Ordinance. In addition, the amount of solid waste generated by the proposed project would not exceed the permitted capacity of the City’s Solid Waste Transfer Station or Keller Canyon Landfill. Therefore, the project would have a lessthan-significant impact.

2.19.2 Sources of Information
California Department of Resources Recycling and Recovery. 2025. SWIS Facility/Site Activity Details, Keller Canyon Landfill (07-AA-0032). Available: https://www2.calrecycle.ca.gov/ SolidWaste/SiteActivity/Details/4407?siteID=228. Accessed: August 1, 2025.

City of Brentwood. 2014. Brentwood General Plan Environmental Impact Report. April. Available:
https://www.brentwoodca.gov/home/showpublisheddocument/2832/637794835332370000.

Accessed: August 1, 2025.
———. 2021. 2020 Urban Water Management Plan. Final. Revised: December 2021. Available:
https://www.brentwoodca.gov/home/showpublisheddocument/3314/637805280436500000.

Contra Costa Water District. 2021. 2020 Urban Water Management Plan. June 2021. Available:
https://www.ccwater.com/DocumentCenter/View/9851/2020-Urban-Water-ManagementPlan-PDF. Accessed: December 9, 2025.

2.20 Wildfire
Potentially
Significant
Impact
Less than
Significant with
Mitigation
Incorporated
Less-thanSignificant
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, and 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? □
□
□
□
□
□
□
□
□
□
□
□
IZI
IZI

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-98 February 2026

2.20.1 Discussion
The project site is located in an urbanized area. According to CAL FIRE’s State Responsibility Area Fire Hazard Severity Zones, Contra Costa County Map (CAL FIRE 2023), the project site is not within a Very High, High, or Moderate Fire Hazard Severity Zone. a) Would the project substantially impair an adopted emergency response plan or emergency evacuation plan?
As discussed above, the project site is not within a Very High, High, or Moderate Fire Hazard Severity Zone. As discussed under Impact f in Section 2.9, Hazards and Hazardous Materials, the proposed project would not impair implementation of or interfere with an adopted emergency response plan or emergency evacuation plan. Therefore, the project would have no impact. b) Would the project due to slope, prevailing winds, and other factors, exacerbate wildfire risks, and thereby expose project occupants to, pollutant concentrations from a wildfire or the uncontrolled spread of a wildfire?
As noted above, the project site is located in a flat area within an urbanized area; it is not located within a designated fire hazard severity zone. There are no areas of dense vegetation that would be susceptible to wildfire. The project involves the construction of a service center that would serve the County. As such, the project would not exacerbate wildfire risk and thereby expose project occupants to pollutant concentrations from a wildfire or the uncontrolled spread of a wildfire.

Therefore, the project would have no impact.
c) Would the project require the installation or maintenance of associated infrastructure (such as roads, fuel breaks, emergency water sources, power lines or other utilities) that may exacerbate fire risk or that may result in temporary or ongoing impacts to the environment? The project involves the construction of a service center and would require the installation of new water, power, and other utility connections. However, the installation of these connections will not exacerbate fire risk since the project is not located in a fire hazard severity zone, is located in an urbanized area and will be constructed to comply with applicable state and local building, engineering, and environmental standards and regulations. Therefore, the project would have no impact.
d) Would the project expose people or structures to significant risks, including downslope or downstream flooding or landslides, as a result of runoff, post-fire slope instability, or drainage changes? The project is limited to the construction of a new service center on relatively flat ground where minor amounts of grading will occur and as such, would not expose people or structures to significant risks, including downslope or downstream flooding or landslides resulting from runoff, post-fire slope instability, or drainage changes. Therefore, the project would have no impact.

2.20.2 Sources of Information
California Department of Forestry and Fire Protection. 2023. Fire Hazard Severity Zones: Find Your Fire Hazard Severity Zone. Available: https://osfm.fire.ca.gov/what-we-do/community-wildfirepreparedness-and-mitigation/fire-hazard-severity-zones.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-99 February 2026

2.21 Mandatory Findings of Significance
Potentially
Significant
Impact
Less than
Significant with
Mitigation
Incorporated
Less-thanSignificant
Impact No Impact
Would the project:
a) Does the project have the 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 impacts 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, the effects of other current projects, and the effects of probable future projects)?
c) Does the project have environmental effects which will cause substantial adverse effects on human beings, either directly or indirectly?

2.21.1 Discussion
a) Does the project have the 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? As discussed under the applicable resource topics in this Initial Study, the proposed facility would house multiple County departments and provide a centralized service center on an undeveloped.

Development of the proposed project could result in potentially significant impacts related to aesthetics, air quality, biological resources, cultural resources, geology and soils (specifically paleontological resources), hazards and hazardous materials, noise, and tribal cultural resources.

However, these impacts would be reduced to a less-than-significant level through implementation of the mitigation measures identified in those respective sections of this Initial Study. Therefore, with the incorporation of mitigation measures, development of the proposed project would not 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, 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 impacts 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, the effects of other current projects, and the effects of probable future projects)?
Four projects in the city of Brentwood are within 0.5 mile of the project site, including the following three residential projects and one commercial project (City of Brentwood 2025a, 2025b):
□ □ □
□ □ □
□ □ □

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-100 February 2026 • 536 Saddle Creek Court: one manufactured home, under review • Emblem Brentwood: 312 apartments and 156 duplex condominiums, under review • Orchard Grove (formerly Adams Lane): 51 single-family homes, under construction • 131 Technology Way: commercial/light industrial shell building, approved There are no County-sponsored projects within 0.5 mile of the project site.

As described throughout Sections 2.1 through 2.20, construction and/or operation of the proposed project would result in individual-level environmental impacts associated with aesthetics, air quality, biological resources, cultural resources, geology and soils (specifically paleontological resources), hazards and hazardous materials, noise, and tribal cultural resources that would be potentially significant without mitigation. Thus, the proposed project could result in cumulativelevel impacts in the project area if impacts are unmitigated and coupled with potential impacts related to development of related projects in the broader geographic area, such as the Emblem Brentwood, Orchard Grove, or 131 Technology Way projects. However, all environmental impacts that could occur as a result of the proposed project would be reduced to a less-than-significant level through the implementation of the mitigation measures identified in those respective sections of this Initial Study. In addition, most of the potential impacts associated with the proposed project would be related to construction-period activities, and would be temporary in nature. Thus, the proposed project would not contribute to regional cumulative impacts in the project area. With respect to cumulative traffic noise, an impact is anticipated along a given roadway if a 3 dB increase in noise would occur in areas where existing ambient and modeled Year 2018 NP noise levels are above the applicable land use compatibility standard or if a 5 dB increase in noise would occur in areas where baseline and resulting noise levels are below the applicable land use compatibility standard. Table 2-16 shows the comparison of noise levels for the Year 2018 NP and Year 2040 WP conditions. As shown in Table 2-17, noise increases due to haul truck activity would not be expected to result in an increase in traffic noise greater than 3 dB along any of the analyzed roadways. The greatest increase in noise from hauling activity was modeled to be 1.5 dB. Because both direct and cumulative traffic noise would not result in an increase of more than 3 dB over existing conditions, cumulative traffic noise impacts would be considered less than significant.

Table 2-17. 2018 No Project and 2040 With Project Traffic Noise Levels Roadway
Modeled
Distance
Modeled 2018 NP Noise
Level (dBA Ldn)
Modeled 2040 WP
Noise Level (dBA Ldn)
Delta dBA
Ldn
Sand Creek Road 50 62.6a 62.9 0.3
Brentwood Boulevard 50 69 70.5 1.5
Business Center Drive 50 62.6a 62.8 0.2
Technology Way 50 62.6a 62.8 0.2
Notes:
a. Measured ambient noise levels (LT-3) are conservatively used to represent this modeling condition.

Based on the analysis presented above for noise and throughout this Initial Study, the proposed project would have a less-than-considerable contribution to cumulative impacts.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-101 February 2026 c) Does the project have environmental effects which will cause substantial adverse effects on human beings, either directly or indirectly?
Construction of the proposed project could expose human beings to adverse effects with respect to air quality and hazardous materials impacts. As described in Section 2.3, Air Quality, implementation of Mitigation Measure AQ-1 would ensure construction-related fugitive dust emissions would be less than significant. As described in Section 2.9, Hazards and Hazardous Materials, ground disturbance during construction could expose construction workers to hazardous materials. Implementation of Mitigation Measure HAZ-1 would require preparation and implementation of a SMP during all ground disturbance (as recommended in the 2024 soil investigation and the 2025 Phase II ESA).

With implementation of the identified mitigation measures in this Initial Study, the proposed project would not have environmental effects that would cause substantial adverse effects on human beings, either directly or indirectly. All identified mitigation measures will be included in the conditions of approval for this project, and the project sponsor will be responsible for implementation of the measures. As a result, there would not be any environmental effects that would cause substantial adverse effects on human beings, either directly or indirectly. Therefore, the project would have a less-than-significant impact with mitigation incorporated.

2.21.2 Sources of Information
City of Brentwood. 2025a. Development Projects (Residential). Available:
https://www.brentwoodca.gov/residents/development-projects-residential. Accessed December 12, 2025.

City of Brentwood. 2025b. Development Projects (Commercial). Available:
https://www.brentwoodca.gov/residents/development-projects-commercial. Accessed December 12, 2025.

East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 3-1 February 2026 Chapter 3
List of Preparers

3.1 Contra Costa County Department of Conservation
and Development (Lead Agency)
• Syd Sotoodeh – Senior Planner

3.2 Contra Costa County Public Works Department
(Project Sponsor)
• Laura Cremin—Environmental Services Division
• Shravan Sundaram—Environmental Services Division

3.3 ICF (Environmental Consultant)
• Heidi Mekkelson—Project Director
• Jessica Viramontes—Project Manager
• Kristi Black—Senior Reviewer
• Jennifer Andersen—Senior Reviewer
• Mario Barrera—Hazards and Hazardous Materials
• Mabel Chan— Aesthetics, Agriculture and Forestry Resources, Energy, Geology/Soils, Land Use/Planning, Mineral Resources, Population/Housing, Public Services, Recreation, Utilities/Services Systems, Wildfire
• Peter Hardie—Noise
• Kelsey Hartfelder—Air Quality and Greenhouse Gas Emissions • Cory Matsui—Air Quality and Greenhouse Gas Emissions
• Jennifer Ostner—Transportation
• Danika Tsao—Biological Resources
• Noah Schumaker—Noise
• Katrina Sukola—Hydrology and Water Quality
• Jason Volk—Noise
• Teresa Giffen—Graphics
• Brent Read—GIS
• John Mathias—Editor

Contra Costa County Public Works Department List of Preparers East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 3-2 February 2026 • Anthony Ha—Document Production

3.4 Cogstone (Cultural and Tribal Cultural Resources)
• John Gust—Principal Investigator
• Sandy Duarte—Author

Attachment A
Air Quality Modeling Data

CalEEMod Inputs

Land Uses for Air Quality Model
Land Use Footprint (Acres) Building Area (SF) Parking Spaces Landscaped Area (SF) Government Office Building 0.96 120,077 - 28,187
Parking Lot 3.58 - 424 -Other Non-Asphalt Surfaces 2.61 - - -

Construction Schedule
Activity Phase Start Date (day/month/year) End Date (day/month/year) Days (Actual) NoteSite Prep: Rough Grading Demolition 9/14/2026 10/14/2026 23 1 monthSite Prep: Trenching & Installation of Underground Utilities Site Preparation 10/15/2026 12/15/2026 44 2 monthsSite Prep: Final Grading Grading 12/16/2026 2/16/2027 45 2 months Construction Building Construction 2/17/2027 10/17/2027 173 8 monthsPaving Paving 10/18/2027 12/18/2027 45 2 monthsArchitectural Coatings Architectural 8/18/2027 12/18/2027 88 4 months

Demo & Earthmoving
Phase Demo (total square feet) Demo (tons) Cut (CY) Fill (CY) Export (CY) Import (CY) Pave (total acres)Demolition 339,535 8,677 - - - - -Grading - - 2,222 3,773 2,222 - - Paving - - - - - - 6.19Note:Tons of demolition calculated using "Asphalt/paving, crushed" conversion factor from CalRecycle Diversion Study Guide, Appendix I Conversion Factors: Construction and Demolition. Assumes depth of 1 foot.

Equipment List
Phase Equipment Type Number/day Hours/day Horsepower
Demolition Rubber Tired Dozers 2 8 367
Demolition Concrete/Industrial Saws 1 8 33Demolition Excavators 3 8 36Site Preparation Rubber Tired Dozers 3 8 367 Site Preparation Tractors/Loaders/Backhoes 4 8 84Grading Graders 1 8 148 Grading Excavators 1 8 36
Grading Tractors/Loaders/Backhoes 3 8 84Grading Rubber Tired Dozers 1 8 367Building Construction Cranes 1 7 367 Building Construction Forklifts 3 8 82Building Construction Generator Sets 1 8 14 Building Construction Welders 1 8 46
Building Construction Tractors/Loaders/Backhoes 3 7 84Paving Pavers 2 8 81 Paving Paving Equipment 2 8 89
Paving Rollers 2 8 36
Architectural Coating Air Compressors 1 6 37
Source: Default

Trips & VMT
Parameter Demolition Site Preparation Grading Building Construction Paving Architectural SourceWorker # 15.0 17.5 15.0 38.4 15.0 7.7 DefaultVendor # 0.0 0.0 0.0 19.7 0.0 0.0 DefaultHauling # 94.3 0.0 16.7 0.0 0.0 0.0 DefaultOnsite truck # 15.0 17.5 15.0 58.1 15.0 7.7 Each truck trip assumed to travel to the centerpoint and return.Worker Length 11.7 11.7 11.7 11.7 11.7 11.7 Default Vendor Length 8.4 8.4 8.4 8.4 8.4 8.4 Default
Hauling Length 20.0 20.0 20.0 20.0 20.0 20.0 DefaultOnsite truck Length 0.2 0.2 0.2 0.2 0.2 0.2 Estimated in Google Earth

East County Service Center
Construction Electricity Use per Year (kWh/year) 393,165Total Construction Electricity Use (kWh) 495,587Average Construction Electricity Use per SF (kWh/SF) 4

MOBILE
Land Use Units Trips Trip RateGovernment (Civic Center) 120 3,285 27.3750Parking Lot 424 - -ENERGYLand Use Units Electricity Use (Default) Natural Gas Use (Default) Additional Electricity Use* Electricity Use (Adjusted) Natural Gas Use (Adjusted)Government (Civic Center) 120 2,541,866 2,851,864 1,109,872 3,651,738 0Parking Lot 424 136,608 0 - 136,608 0Notes:*Electricity rates calculated by summing default electricity consumption with electricity consumption per end use using rates from Table E-15.2 in CAPCOA 2021 (https://www.caleemod.com/documents/handbook/full_handbook.pdf)CEC demand forecast zone: 1Electricity use provided in kWh/year; natural gas use provided in kBTU/year.WATERDefaultWASTEDefaultSTATIONARYEquipment Fuel Type Kilowatt Horsepower # Per Day Hours Per Day Hours Per YearEmergency Generator Diesel 250 335 1 0.5 108Emission FactorsSource Units CO NOx PM10 PM2.5 ROG TOGBAAQMD TBACT (300-600HP) g/bhp-hr 2.6 0.29 0.015 0.015 0.15 0.15https://www.baaqmd.gov/~/media/files/engineering/bact-tbact-workshop/combustion/96-1-3.pdf?rev=210312454f084efe9dba8846cda4d372https://www.baaqmd.gov/~/media/files/engineering/workshops/diesel-bact-102124/bact-tbact-webinar-presentation-21oct2024-pdf.pdf?rev=8984ea91fb1c48088b3232dd04820e55&sc_lang=enhttps://19january2017snapshot.epa.gov/www3/otaq/models/nonrdmdl/nonrdmdl2005/420r05015.pdf#page=5

CalEEMod Files

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East County Service Center Detailed Report
Table of Contents

1. Basic Project Information

1.1. Basic Project Information

1.2. Land Use Types

1.3. User-Selected Emission Reduction Measures by Emissions Sector

2. Emissions Summary

2.1. Construction Emissions Compared Against Thresholds

2.2. Construction Emissions by Year, Unmitigated

2.4. Operations Emissions Compared Against Thresholds

2.5. Operations Emissions by Sector, Unmitigated

3. Construction Emissions Details

3.1. Demolition (2026) - Unmitigated

3.3. Site Preparation (2026) - Unmitigated

3.5. Grading (2026) - Unmitigated

3.7. Grading (2027) - Unmitigated

3.9. Building Construction (2027) - Unmitigated

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3.11. Paving (2027) - Unmitigated

3.13. Architectural Coating (2027) - Unmitigated

4. Operations Emissions Details

4.1. Mobile Emissions by Land Use

4.1.1. Unmitigated

4.2. Energy

4.2.1. Electricity Emissions By Land Use - Unmitigated

4.2.3. Natural Gas Emissions By Land Use - Unmitigated

4.3. Area Emissions by Source

4.3.1. Unmitigated

4.4. Water Emissions by Land Use

4.4.1. Unmitigated

4.5. Waste Emissions by Land Use

4.5.1. Unmitigated

4.6. Refrigerant Emissions by Land Use

4.6.1. Unmitigated

4.7. Offroad Emissions By Equipment Type

4.7.1. Unmitigated

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4.8. Stationary Emissions By Equipment Type

4.8.1. Unmitigated

4.9. User Defined Emissions By Equipment Type

4.9.1. Unmitigated

4.10. Soil Carbon Accumulation By Vegetation Type

4.10.1. Soil Carbon Accumulation By Vegetation Type - Unmitigated

4.10.2. Above and Belowground Carbon Accumulation by Land Use Type - Unmitigated

4.10.3. Avoided and Sequestered Emissions by Species - Unmitigated

5. Activity Data

5.1. Construction Schedule

5.2. Off-Road Equipment

5.2.1. Unmitigated

5.3. Construction Vehicles

5.3.1. Unmitigated

5.4. Vehicles

5.4.1. Construction Vehicle Control Strategies

5.5. Architectural Coatings

5.6. Dust Mitigation

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5.6.1. Construction Earthmoving Activities

5.6.2. Construction Earthmoving Control Strategies

5.7. Construction Paving

5.8. Construction Electricity Consumption and Emissions Factors

5.9. Operational Mobile Sources

5.9.1. Unmitigated

5.10. Operational Area Sources

5.10.1. Hearths

5.10.1.1. Unmitigated

5.10.2. Architectural Coatings

5.10.3. Landscape Equipment

5.11. Operational Energy Consumption

5.11.1. Unmitigated

5.12. Operational Water and Wastewater Consumption

5.12.1. Unmitigated

5.13. Operational Waste Generation

5.13.1. Unmitigated

5.14. Operational Refrigeration and Air Conditioning Equipment

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5.14.1. Unmitigated

5.15. Operational Off-Road Equipment

5.15.1. Unmitigated

5.16. Stationary Sources

5.16.1. Emergency Generators and Fire Pumps

5.16.2. Process Boilers

5.17. User Defined

5.18. Vegetation

5.18.1. Land Use Change

5.18.1.1. Unmitigated

5.18.1. Biomass Cover Type

5.18.1.1. Unmitigated

5.18.2. Sequestration

5.18.2.1. Unmitigated

6. Climate Risk Detailed Report

6.1. Climate Risk Summary

6.2. Initial Climate Risk Scores

6.3. Adjusted Climate Risk Scores

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6.4. Climate Risk Reduction Measures

7. Health and Equity Details

7.1. CalEnviroScreen 4.0 Scores

7.2. Healthy Places Index Scores

7.3. Overall Health & Equity Scores

7.4. Health & Equity Measures

7.5. Evaluation Scorecard

7.6. Health & Equity Custom Measures

8. User Changes to Default Data

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1. Basic Project Information

1.1. Basic Project Information
Data Field Value
Project Name East County Service Center
Construction Start Date 3/15/2027
Operational Year 2029
Lead Agency —
Land Use Scale Project/site
Analysis Level for Defaults County
Windspeed (m/s) 3.00
Precipitation (days) 20.6
Location Technology Way, Brentwood, CA 94513, USA
County Contra Costa
City Brentwood
Air District Bay Area AQMD
Air Basin San Francisco Bay Area
TAZ 1363
EDFZ 1
Electric Utility Pacific Gas & Electric Company
Gas Utility Pacific Gas & Electric
App Version 2022.1.1.29

1.2. Land Use Types
Land Use Subtype Size Unit Lot Acreage Building Area (sq ft) Landscape Area (sq ft)
Special Landscape
Area (sq ft)
Population Description
Government (Civic
Center)
120 1000sqft 0.87 120,077 28,187 — — —

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Parking Lot 424 Space 3.58 0.00 0.00 — — —
Other Non-Asphalt
Surfaces

2.61 Acre 2.61 0.00 0.00 — — —

1.3. User-Selected Emission Reduction Measures by Emissions Sector No measures selected

2. Emissions Summary

2.1. Construction Emissions Compared Against Thresholds Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Un/Mit. TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Unmit. 16.7 16.4 29.2 23.8 0.08 0.97 12.4 13.4 0.86 2.51 3.37 — 11,233 11,233 0.84 1.12 14.3 11,603 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Unmit. 16.7 16.4 29.6 29.6 0.08 1.24 12.4 13.4 1.14 4.17 5.31 — 11,225 11,225 0.84 1.12 0.37 11,581 Average
Daily
(Max)
— — — — — — — — — — — — — — — — — —
Unmit. 4.71 4.51 7.81 10.5 0.02 0.26 2.77 3.03 0.24 0.71 0.93 — 2,452 2,452 0.15 0.09 0.62 2,483 Annual
(Max)
— — — — — — — — — — — — — — — — — —
Unmit. 0.86 0.82 1.42 1.91 < 0.005 0.05 0.50 0.55 0.04 0.13 0.17 — 406 406 0.02 0.01 0.10 411

2.2. Construction Emissions by Year, Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Year TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e -------------------
------------------- Page 179 of 1860
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Daily -
Summer
(Max)
— — — — — — — — — — — — — — — — — —
2026 3.47 2.49 29.2 23.8 0.08 0.97 12.4 13.4 0.86 2.51 3.37 — 11,233 11,233 0.84 1.12 14.3 11,603 2027 16.7 16.4 11.9 16.8 0.03 0.36 5.06 5.43 0.34 0.81 1.15 — 3,819 3,819 0.22 0.14 2.53 3,869 Daily -
Winter
(Max)
— — — — — — — — — — — — — — — — — —
2026 3.82 3.21 29.6 29.6 0.08 1.24 12.4 13.4 1.14 4.17 5.31 — 11,225 11,225 0.84 1.12 0.37 11,581 2027 16.7 16.4 16.0 18.6 0.04 0.61 5.06 5.61 0.56 1.80 2.36 — 4,491 4,491 0.26 0.22 0.07 4,563 Average
Daily
— — — — — — — — — — — — — — — — — —
2026 0.75 0.60 5.93 5.64 0.01 0.23 2.01 2.25 0.21 0.71 0.93 — 1,657 1,657 0.11 0.09 0.46 1,687 2027 4.71 4.51 7.81 10.5 0.02 0.26 2.77 3.03 0.24 0.54 0.78 — 2,452 2,452 0.15 0.09 0.62 2,483 Annual — — — — — — — — — — — — — — — — — —
2026 0.14 0.11 1.08 1.03 < 0.005 0.04 0.37 0.41 0.04 0.13 0.17 — 274 274 0.02 0.01 0.08 279 2027 0.86 0.82 1.42 1.91 < 0.005 0.05 0.50 0.55 0.04 0.10 0.14 — 406 406 0.02 0.01 0.10 411

2.4. Operations Emissions Compared Against Thresholds
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Un/Mit. TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Unmit. 14.3 13.7 5.32 62.4 0.13 0.10 12.1 12.2 0.09 3.07 3.16 414 15,464 15,879 42.5 0.73 34.2 17,193 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Unmit. 12.9 12.2 6.21 56.9 0.12 0.09 12.1 12.2 0.08 3.07 3.15 414 14,573 14,987 42.7 0.79 1.17 16,291 Average
Daily
(Max)
— — — — — — — — — — — — — — — — — —
-------------------

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Unmit. 10.4 9.95 4.16 40.9 0.09 0.07 8.53 8.60 0.06 2.16 2.22 414 11,103 11,517 42.4 0.59 10.7 12,764 Annual
(Max)
— — — — — — — — — — — — — — — — — —
Unmit. 1.90 1.82 0.76 7.46 0.02 0.01 1.56 1.57 0.01 0.39 0.41 68.6 1,838 1,907 7.02 0.10 1.78 2,113

2.5. Operations Emissions by Sector, Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Sector TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Mobile 10.4 9.86 5.20 56.5 0.13 0.08 12.1 12.2 0.08 3.07 3.15 — 13,098 13,098 0.65 0.57 33.9 13,319 Area 3.88 3.81 0.04 5.22 < 0.005 0.01 — 0.01 0.01 — 0.01 — 21.5 21.5 < 0.005 < 0.005 — 21.6 Energy 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 — 0.00 — 2,117 2,117 0.34 0.04 — 2,138 Water — — — — — — — — — — — 45.7 87.2 133 4.70 0.11 — 284 Waste — — — — — — — — — — — 369 0.00 369 36.8 0.00 — 1,290 Refrig. — — — — — — — — — — — — — — — — 0.29 0.29
Stationa
ry

0.04 0.04 0.08 0.70 < 0.005 < 0.005 0.00 < 0.005 < 0.005 0.00 < 0.005 0.00 141 141 0.01 < 0.005 0.00 141 Total 14.3 13.7 5.32 62.4 0.13 0.10 12.1 12.2 0.09 3.07 3.16 414 15,464 15,879 42.5 0.73 34.2 17,193 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Mobile 9.86 9.25 6.13 56.2 0.12 0.08 12.1 12.2 0.08 3.07 3.15 — 12,228 12,228 0.77 0.64 0.88 12,438 Area 2.95 2.95 — — — — — — — — — — — — — — — —
Energy 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 — 0.00 — 2,117 2,117 0.34 0.04 — 2,138 Water — — — — — — — — — — — 45.7 87.2 133 4.70 0.11 — 284 Waste — — — — — — — — — — — 369 0.00 369 36.8 0.00 — 1,290 Refrig. — — — — — — — — — — — — — — — — 0.29 0.29
Stationa
ry

0.04 0.04 0.08 0.70 < 0.005 < 0.005 0.00 < 0.005 < 0.005 0.00 < 0.005 0.00 141 141 0.01 < 0.005 0.00 141 -------------------

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Total 12.9 12.2 6.21 56.9 0.12 0.09 12.1 12.2 0.08 3.07 3.15 414 14,573 14,987 42.7 0.79 1.17 16,291 Average
Daily
— — — — — — — — — — — — — — — — — —
Mobile 6.97 6.55 4.10 37.9 0.09 0.06 8.53 8.59 0.06 2.16 2.22 — 8,805 8,805 0.51 0.44 10.5 8,958 Area 3.41 3.38 0.02 2.58 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 10.6 10.6 < 0.005 < 0.005 — 10.6 Energy 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 — 0.00 — 2,117 2,117 0.34 0.04 — 2,138 Water — — — — — — — — — — — 45.7 87.2 133 4.70 0.11 — 284 Waste — — — — — — — — — — — 369 0.00 369 36.8 0.00 — 1,290 Refrig. — — — — — — — — — — — — — — — — 0.29 0.29
Stationa
ry

0.02 0.02 0.05 0.41 < 0.005 < 0.005 0.00 < 0.005 < 0.005 0.00 < 0.005 0.00 83.2 83.2 < 0.005 < 0.005 0.00 83.5 Total 10.4 9.95 4.16 40.9 0.09 0.07 8.53 8.60 0.06 2.16 2.22 414 11,103 11,517 42.4 0.59 10.7 12,764 Annual — — — — — — — — — — — — — — — — — —
Mobile 1.27 1.20 0.75 6.92 0.02 0.01 1.56 1.57 0.01 0.39 0.40 — 1,458 1,458 0.08 0.07 1.73 1,483 Area 0.62 0.62 < 0.005 0.47 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 1.75 1.75 < 0.005 < 0.005 — 1.76 Energy 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 — 0.00 — 351 351 0.06 0.01 — 354 Water — — — — — — — — — — — 7.56 14.4 22.0 0.78 0.02 — 47.0 Waste — — — — — — — — — — — 61.0 0.00 61.0 6.10 0.00 — 214 Refrig. — — — — — — — — — — — — — — — — 0.05 0.05
Stationa
ry
< 0.005 < 0.005 0.01 0.08 < 0.005 < 0.005 0.00 < 0.005 < 0.005 0.00 < 0.005 0.00 13.8 13.8 < 0.005 < 0.005 0.00 13.8 Total 1.90 1.82 0.76 7.46 0.02 0.01 1.56 1.57 0.01 0.39 0.41 68.6 1,838 1,907 7.02 0.10 1.78 2,113

3. Construction Emissions Details

3.1. Demolition (2026) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e -------------------
Onsite — — — — — — — — — — — — — — — — — —

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Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

2.72 2.29 20.7 19.0 0.03 0.84 — 0.84 0.78 — 0.78 — 3,427 3,427 0.14 0.03 — 3,438 Demoliti
on
— — — — — — 5.30 5.30 — 0.80 0.80 — — — — — — —
Onsite
truck

0.02 0.01 0.22 0.16 < 0.005 < 0.005 0.68 0.68 < 0.005 0.07 0.07 — 34.8 34.8 0.01 0.01 0.02 36.7 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

2.72 2.29 20.7 19.0 0.03 0.84 — 0.84 0.78 — 0.78 — 3,427 3,427 0.14 0.03 — 3,438 Demoliti
on
— — — — — — 5.30 5.30 — 0.80 0.80 — — — — — — —
Onsite
truck

0.02 0.01 0.23 0.16 < 0.005 < 0.005 0.68 0.68 < 0.005 0.07 0.07 — 35.2 35.2 0.01 0.01 < 0.005 37.1 Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.17 0.14 1.30 1.20 < 0.005 0.05 — 0.05 0.05 — 0.05 — 216 216 0.01 < 0.005 — 217 Demoliti
on
— — — — — — 0.33 0.33 — 0.05 0.05 — — — — — — —
Onsite
truck
< 0.005 < 0.005 0.01 0.01 < 0.005 < 0.005 0.04 0.04 < 0.005 < 0.005 < 0.005 — 2.20 2.20 < 0.005 < 0.005 < 0.005 2.32 Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.03 0.03 0.24 0.22 < 0.005 0.01 — 0.01 0.01 — 0.01 — 35.7 35.7 < 0.005 < 0.005 — 35.9

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Demoliti — — — — — — 0.06 0.06 — 0.01 0.01 — — — — — — — Onsite
truck
< 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 0.01 0.01 < 0.005 < 0.005 < 0.005 — 0.36 0.36 < 0.005 < 0.005 < 0.005 0.38 Offsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.05 0.05 0.03 0.59 0.00 0.00 0.51 0.51 0.00 0.13 0.13 — 130 130 < 0.005 < 0.005 0.48 132 Vendor 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 0.00 Hauling 0.67 0.14 8.27 4.00 0.04 0.12 5.91 6.03 0.08 1.52 1.60 — 6,620 6,620 0.52 1.06 13.8 6,964 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.05 0.04 0.04 0.50 0.00 0.00 0.51 0.51 0.00 0.13 0.13 — 119 119 < 0.005 0.01 0.01 120 Vendor 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 0.00 Hauling 0.66 0.14 8.67 4.03 0.04 0.12 5.91 6.03 0.08 1.52 1.60 — 6,622 6,622 0.52 1.06 0.36 6,953 Average
Daily
— — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.03 0.00 0.00 0.03 0.03 0.00 0.01 0.01 — 7.56 7.56 < 0.005 < 0.005 0.01 7.67 Vendor 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 0.00 Hauling 0.04 0.01 0.54 0.25 < 0.005 0.01 0.37 0.38 0.01 0.09 0.10 — 417 417 0.03 0.07 0.37 438 Annual — — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.01 0.00 0.00 0.01 0.01 0.00 < 0.005 < 0.005 — 1.25 1.25 < 0.005 < 0.005 < 0.005 1.27 Vendor 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 0.00 Hauling 0.01 < 0.005 0.10 0.05 < 0.005 < 0.005 0.07 0.07 < 0.005 0.02 0.02 — 69.1 69.1 0.01 0.01 0.06 72.6

3.3. Site Preparation (2026) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e -------------------
Onsite — — — — — — — — — — — — — — — — — —

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Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

3.74 3.14 29.2 28.8 0.05 1.24 — 1.24 1.14 — 1.14 — 5,298 5,298 0.21 0.04 — 5,316 Dust
From
Material
Movement
— — — — — — 7.67 7.67 — 3.94 3.94 — — — — — — —
Onsite
truck

0.02 0.01 0.27 0.19 < 0.005 < 0.005 0.80 0.80 < 0.005 0.08 0.08 — 41.0 41.0 0.01 0.01 < 0.005 43.3 Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.45 0.38 3.52 3.47 0.01 0.15 — 0.15 0.14 — 0.14 — 639 639 0.03 0.01 — 641 Dust
From
Material
Movement
— — — — — — 0.92 0.92 — 0.47 0.47 — — — — — — —
Onsite
truck
< 0.005 < 0.005 0.03 0.02 < 0.005 < 0.005 0.09 0.09 < 0.005 0.01 0.01 — 4.91 4.91 < 0.005 < 0.005 < 0.005 5.19 Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.08 0.07 0.64 0.63 < 0.005 0.03 — 0.03 0.03 — 0.03 — 106 106 < 0.005 < 0.005 — 106 Dust
From
Material
Movement
— — — — — — 0.17 0.17 — 0.09 0.09 — — — — — — —

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Onsite < 0.005 < 0.005 0.01 < 0.005 < 0.005 < 0.005 0.02 0.02 < 0.005 < 0.005 < 0.005 — 0.81 0.81 < 0.005 < 0.005 < 0.005 0.86 truck
Offsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.06 0.05 0.05 0.58 0.00 0.00 0.60 0.60 0.00 0.15 0.15 — 138 138 < 0.005 0.01 0.01 140 Vendor 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 0.00 Hauling 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 0.00 Average
Daily
— — — — — — — — — — — — — — — — — —
Worker 0.01 0.01 0.01 0.07 0.00 0.00 0.07 0.07 0.00 0.02 0.02 — 16.9 16.9 < 0.005 < 0.005 0.03 17.1 Vendor 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 0.00 Hauling 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 0.00 Annual — — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.01 0.00 0.00 0.01 0.01 0.00 < 0.005 < 0.005 — 2.79 2.79 < 0.005 < 0.005 < 0.005 2.83 Vendor 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 0.00 Hauling 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 0.00

3.5. Grading (2026) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Onsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
-------------------

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Off-Roa
Equipment

1.96 1.65 15.0 17.4 0.03 0.65 — 0.65 0.59 — 0.59 — 2,960 2,960 0.12 0.02 — 2,970 Dust
From
Material
Movement
— — — — — — 2.77 2.77 — 1.34 1.34 — — — — — — —
Onsite
truck

0.02 0.01 0.23 0.16 < 0.005 < 0.005 0.68 0.68 < 0.005 0.07 0.07 — 35.2 35.2 0.01 0.01 < 0.005 37.1 Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.06 0.05 0.47 0.55 < 0.005 0.02 — 0.02 0.02 — 0.02 — 92.7 92.7 < 0.005 < 0.005 — 93.0 Dust
From
Material
Movement
— — — — — — 0.09 0.09 — 0.04 0.04 — — — — — — —
Onsite
truck
< 0.005 < 0.005 0.01 0.01 < 0.005 < 0.005 0.02 0.02 < 0.005 < 0.005 < 0.005 — 1.09 1.09 < 0.005 < 0.005 < 0.005 1.16 Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.01 0.01 0.09 0.10 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 15.3 15.3 < 0.005 < 0.005 — 15.4 Dust
From
Material
Movement
— — — — — — 0.02 0.02 — 0.01 0.01 — — — — — — —
Onsite
truck
< 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 — 0.18 0.18 < 0.005 < 0.005 < 0.005 0.19 Offsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —

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Daily, — — — — — — — — — — — — — — — — — —
Winter
(Max)
Worker 0.05 0.04 0.04 0.50 0.00 0.00 0.51 0.51 0.00 0.13 0.13 — 119 119 < 0.005 0.01 0.01 120 Vendor 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 0.00 Hauling 0.12 0.02 1.53 0.71 0.01 0.02 1.04 1.07 0.01 0.27 0.28 — 1,170 1,170 0.09 0.19 0.06 1,228 Average
Daily
— — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.02 0.00 0.00 0.02 0.02 0.00 < 0.005 < 0.005 — 3.75 3.75 < 0.005 < 0.005 0.01 3.81 Vendor 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 0.00 Hauling < 0.005 < 0.005 0.05 0.02 < 0.005 < 0.005 0.03 0.03 < 0.005 0.01 0.01 — 36.6 36.6 < 0.005 0.01 0.03 38.5 Annual — — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 < 0.005 0.00 0.00 < 0.005 < 0.005 0.00 < 0.005 < 0.005 — 0.62 0.62 < 0.005 < 0.005 < 0.005 0.63 Vendor 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 0.00 Hauling < 0.005 < 0.005 0.01 < 0.005 < 0.005 < 0.005 0.01 0.01 < 0.005 < 0.005 < 0.005 — 6.06 6.06 < 0.005 < 0.005 0.01 6.37

3.7. Grading (2027) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Onsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

1.89 1.59 14.2 17.3 0.03 0.60 — 0.60 0.55 — 0.55 — 2,960 2,960 0.12 0.02 — 2,970 -------------------

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Dust — — — — — — 2.77 2.77 — 1.34 1.34 — — — — — — —
From
Material
Movement
Onsite
truck

0.02 0.01 0.23 0.16 < 0.005 < 0.005 0.68 0.68 < 0.005 0.07 0.07 — 34.6 34.6 0.01 0.01 < 0.005 36.5 Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.17 0.15 1.31 1.59 < 0.005 0.05 — 0.05 0.05 — 0.05 — 272 272 0.01 < 0.005 — 273 Dust
From
Material
Movement
— — — — — — 0.25 0.25 — 0.12 0.12 — — — — — — —
Onsite
truck
< 0.005 < 0.005 0.02 0.01 < 0.005 < 0.005 0.06 0.06 < 0.005 0.01 0.01 — 3.16 3.16 < 0.005 < 0.005 < 0.005 3.34 Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.03 0.03 0.24 0.29 < 0.005 0.01 — 0.01 0.01 — 0.01 — 45.1 45.1 < 0.005 < 0.005 — 45.2 Dust
From
Material
Movement
— — — — — — 0.05 0.05 — 0.02 0.02 — — — — — — —
Onsite
truck
< 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 0.01 0.01 < 0.005 < 0.005 < 0.005 — 0.52 0.52 < 0.005 < 0.005 < 0.005 0.55 Offsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.05 0.04 0.04 0.47 0.00 0.00 0.51 0.51 0.00 0.13 0.13 — 116 116 < 0.005 0.01 0.01 118 Page 189 of 1860 East County Service Center Detailed Report, 7/8/2025
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Vendor 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 0.00 Hauling 0.11 0.02 1.48 0.70 0.01 0.01 1.04 1.06 0.01 0.27 0.28 — 1,144 1,144 0.08 0.18 0.06 1,200 Average
Daily
— — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.04 0.00 0.00 0.05 0.05 0.00 0.01 0.01 — 10.8 10.8 < 0.005 < 0.005 0.02 11.0 Vendor 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 0.00 Hauling 0.01 < 0.005 0.13 0.06 < 0.005 < 0.005 0.09 0.10 < 0.005 0.02 0.03 — 105 105 0.01 0.02 0.09 110 Annual — — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.01 0.00 0.00 0.01 0.01 0.00 < 0.005 < 0.005 — 1.79 1.79 < 0.005 < 0.005 < 0.005 1.82 Vendor 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 0.00 Hauling < 0.005 < 0.005 0.02 0.01 < 0.005 < 0.005 0.02 0.02 < 0.005 < 0.005 < 0.005 — 17.4 17.4 < 0.005 < 0.005 0.01 18.3

3.9. Building Construction (2027) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Onsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

1.23 1.03 9.39 12.9 0.02 0.34 — 0.34 0.31 — 0.31 — 2,397 2,397 0.10 0.02 — 2,405 Onsite
truck

0.08 0.04 0.85 0.61 < 0.005 < 0.005 2.64 2.64 < 0.005 0.26 0.26 — 132 132 0.04 0.02 0.08 140 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

1.23 1.03 9.39 12.9 0.02 0.34 — 0.34 0.31 — 0.31 — 2,397 2,397 0.10 0.02 — 2,405 -------------------

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Onsite
truck

0.08 0.03 0.89 0.63 < 0.005 < 0.005 2.64 2.64 < 0.005 0.26 0.26 — 134 134 0.04 0.02 < 0.005 141 Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.58 0.49 4.45 6.13 0.01 0.16 — 0.16 0.15 — 0.15 — 1,136 1,136 0.05 0.01 — 1,140 Onsite
truck

0.04 0.02 0.41 0.29 < 0.005 < 0.005 1.18 1.18 < 0.005 0.12 0.12 — 63.0 63.0 0.02 0.01 0.02 66.6 Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.11 0.09 0.81 1.12 < 0.005 0.03 — 0.03 0.03 — 0.03 — 188 188 0.01 < 0.005 — 189 Onsite
truck

0.01 < 0.005 0.08 0.05 < 0.005 < 0.005 0.22 0.22 < 0.005 0.02 0.02 — 10.4 10.4 < 0.005 < 0.005 < 0.005 11.0 Offsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.13 0.12 0.08 1.41 0.00 0.00 1.31 1.31 0.00 0.32 0.32 — 326 326 0.01 0.01 1.11 331 Vendor 0.05 0.02 0.64 0.31 < 0.005 0.01 0.50 0.51 0.01 0.13 0.14 — 511 511 0.03 0.08 1.11 536 Hauling 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 0.00 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.12 0.11 0.10 1.19 0.00 0.00 1.31 1.31 0.00 0.32 0.32 — 298 298 0.01 0.01 0.03 302 Vendor 0.04 0.02 0.67 0.32 < 0.005 0.01 0.50 0.51 0.01 0.13 0.14 — 512 512 0.03 0.08 0.03 535 Hauling 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 0.00 Average
Daily
— — — — — — — — — — — — — — — — — —
Worker 0.06 0.05 0.04 0.55 0.00 0.00 0.61 0.61 0.00 0.15 0.15 — 143 143 < 0.005 0.01 0.23 145 Vendor 0.02 0.01 0.31 0.15 < 0.005 < 0.005 0.24 0.24 < 0.005 0.06 0.06 — 242 242 0.01 0.04 0.23 254

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Hauling 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 0.00 Annual — — — — — — — — — — — — — — — — — —
Worker 0.01 0.01 0.01 0.10 0.00 0.00 0.11 0.11 0.00 0.03 0.03 — 23.7 23.7 < 0.005 < 0.005 0.04 24.0 Vendor < 0.005 < 0.005 0.06 0.03 < 0.005 < 0.005 0.04 0.04 < 0.005 0.01 0.01 — 40.1 40.1 < 0.005 0.01 0.04 42.0 Hauling 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 0.00

3.11. Paving (2027) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Onsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.88 0.74 6.94 9.95 0.01 0.30 — 0.30 0.27 — 0.27 — 1,511 1,511 0.06 0.01 — 1,516 Paving 0.21 0.21 — — — — — — — — — — — — — — — —
Onsite
truck

0.02 0.01 0.23 0.16 < 0.005 < 0.005 0.68 0.68 < 0.005 0.07 0.07 — 34.6 34.6 0.01 0.01 < 0.005 36.5 Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.11 0.09 0.86 1.23 < 0.005 0.04 — 0.04 0.03 — 0.03 — 186 186 0.01 < 0.005 — 187 Paving 0.03 0.03 — — — — — — — — — — — — — — — —
Onsite
truck
< 0.005 < 0.005 0.03 0.02 < 0.005 < 0.005 0.08 0.08 < 0.005 0.01 0.01 — 4.23 4.23 < 0.005 < 0.005 < 0.005 4.47 Annual — — — — — — — — — — — — — — — — — —
-------------------

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Off-Roa
Equipment

0.02 0.02 0.16 0.22 < 0.005 0.01 — 0.01 0.01 — 0.01 — 30.8 30.8 < 0.005 < 0.005 — 31.0 Paving < 0.005 < 0.005 — — — — — — — — — — — — — — — —
Onsite
truck
< 0.005 < 0.005 0.01 < 0.005 < 0.005 < 0.005 0.01 0.01 < 0.005 < 0.005 < 0.005 — 0.70 0.70 < 0.005 < 0.005 < 0.005 0.74 Offsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.05 0.04 0.04 0.47 0.00 0.00 0.51 0.51 0.00 0.13 0.13 — 116 116 < 0.005 0.01 0.01 118 Vendor 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 0.00 Hauling 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 0.00 Average
Daily
— — — — — — — — — — — — — — — — — —
Worker 0.01 0.01 < 0.005 0.06 0.00 0.00 0.06 0.06 0.00 0.02 0.02 — 14.5 14.5 < 0.005 < 0.005 0.02 14.7 Vendor 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 0.00 Hauling 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 0.00 Annual — — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.01 0.00 0.00 0.01 0.01 0.00 < 0.005 < 0.005 — 2.40 2.40 < 0.005 < 0.005 < 0.005 2.44 Vendor 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 0.00 Hauling 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 0.00

3.13. Architectural Coating (2027) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e -------------------
Onsite — — — — — — — — — — — — — — — — — —

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Daily, — — — — — — — — — — — — — — — — — —
Summer
(Max)
Off-Roa
d
Equipm
ent

0.14 0.11 0.83 1.13 < 0.005 0.02 — 0.02 0.02 — 0.02 — 134 134 0.01 < 0.005 — 134 Architect
ural
Coating
s

15.1 15.1 — — — — — — — — — — — — — — — —
Onsite
truck

0.01 < 0.005 0.11 0.08 < 0.005 < 0.005 0.35 0.35 < 0.005 0.03 0.04 — 17.5 17.5 0.01 < 0.005 0.01 18.5 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.14 0.11 0.83 1.13 < 0.005 0.02 — 0.02 0.02 — 0.02 — 134 134 0.01 < 0.005 — 134 Architect
ural
Coating
s

15.1 15.1 — — — — — — — — — — — — — — — —
Onsite
truck

0.01 < 0.005 0.12 0.08 < 0.005 < 0.005 0.35 0.35 < 0.005 0.03 0.04 — 17.8 17.8 0.01 < 0.005 < 0.005 18.7 Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.03 0.03 0.20 0.27 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 32.2 32.2 < 0.005 < 0.005 — 32.3 Architect
ural
Coating
s

3.64 3.64 — — — — — — — — — — — — — — — —
Onsite
truck
< 0.005 < 0.005 0.03 0.02 < 0.005 < 0.005 0.08 0.08 < 0.005 0.01 0.01 — 4.25 4.25 < 0.005 < 0.005 < 0.005 4.49

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Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.01 < 0.005 0.04 0.05 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 5.33 5.33 < 0.005 < 0.005 — 5.35 Architect
ural
Coating
s

0.66 0.66 — — — — — — — — — — — — — — — —
Onsite
truck
< 0.005 < 0.005 0.01 < 0.005 < 0.005 < 0.005 0.01 0.01 < 0.005 < 0.005 < 0.005 — 0.70 0.70 < 0.005 < 0.005 < 0.005 0.74 Offsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.03 0.02 0.02 0.28 0.00 0.00 0.26 0.26 0.00 0.06 0.06 — 65.2 65.2 < 0.005 < 0.005 0.22 66.2 Vendor 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 0.00 Hauling 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 0.00 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.02 0.02 0.02 0.24 0.00 0.00 0.26 0.26 0.00 0.06 0.06 — 59.6 59.6 < 0.005 < 0.005 0.01 60.5 Vendor 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 0.00 Hauling 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 0.00 Average
Daily
— — — — — — — — — — — — — — — — — —
Worker 0.01 0.01 < 0.005 0.06 0.00 0.00 0.06 0.06 0.00 0.02 0.02 — 14.5 14.5 < 0.005 < 0.005 0.02 14.7 Vendor 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 0.00 Hauling 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 0.00 Annual — — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.01 0.00 0.00 0.01 0.01 0.00 < 0.005 < 0.005 — 2.41 2.41 < 0.005 < 0.005 < 0.005 2.44 Vendor 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 0.00 Hauling 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 0.00 Page 195 of 1860 East County Service Center Detailed Report, 7/8/2025
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4. Operations Emissions Details

4.1. Mobile Emissions by Land Use

4.1.1. Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Land
Use
TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Govern
ment
(Civic
Center)

10.4 9.86 5.20 56.5 0.13 0.08 12.1 12.2 0.08 3.07 3.15 — 13,098 13,098 0.65 0.57 33.9 13,319 Parking
Lot

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 0.00 Other
Non-Asphalt
Surfaces

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 0.00 Total 10.4 9.86 5.20 56.5 0.13 0.08 12.1 12.2 0.08 3.07 3.15 — 13,098 13,098 0.65 0.57 33.9 13,319 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Govern
ment
(Civic
Center)

9.86 9.25 6.13 56.2 0.12 0.08 12.1 12.2 0.08 3.07 3.15 — 12,228 12,228 0.77 0.64 0.88 12,438 Parking
Lot

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 0.00 Other
Non-Asphalt
Surfaces

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 0.00 Total 9.86 9.25 6.13 56.2 0.12 0.08 12.1 12.2 0.08 3.07 3.15 — 12,228 12,228 0.77 0.64 0.88 12,438

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Annual — — — — — — — — — — — — — — — — — —
Govern
ment
(Civic
Center)

1.27 1.20 0.75 6.92 0.02 0.01 1.56 1.57 0.01 0.39 0.40 — 1,458 1,458 0.08 0.07 1.73 1,483 Parking
Lot

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 0.00 Other
Non-Asphalt
Surfaces

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 0.00 Total 1.27 1.20 0.75 6.92 0.02 0.01 1.56 1.57 0.01 0.39 0.40 — 1,458 1,458 0.08 0.07 1.73 1,483

4.2. Energy

4.2.1. Electricity Emissions By Land Use - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Land
Use
TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Govern
ment
(Civic
Center)
— — — — — — — — — — — — 2,041 2,041 0.33 0.04 — 2,061
Parking
Lot
— — — — — — — — — — — — 76.3 76.3 0.01 < 0.005 — 77.1
Other
Non-Asphalt
Surfaces
— — — — — — — — — — — — 0.00 0.00 0.00 0.00 — 0.00
Total — — — — — — — — — — — — 2,117 2,117 0.34 0.04 — 2,138 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —

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Govern — — — — — — — — — — — — 2,041 2,041 0.33 0.04 — 2,061 ment
Parking
Lot
— — — — — — — — — — — — 76.3 76.3 0.01 < 0.005 — 77.1
Other
Non-Asphalt
Surfaces
— — — — — — — — — — — — 0.00 0.00 0.00 0.00 — 0.00
Total — — — — — — — — — — — — 2,117 2,117 0.34 0.04 — 2,138 Annual — — — — — — — — — — — — — — — — — —
Govern
ment
(Civic
Center)
— — — — — — — — — — — — 338 338 0.05 0.01 — 341
Parking
Lot
— — — — — — — — — — — — 12.6 12.6 < 0.005 < 0.005 — 12.8 Other
Non-Asphalt
Surfaces
— — — — — — — — — — — — 0.00 0.00 0.00 0.00 — 0.00
Total — — — — — — — — — — — — 351 351 0.06 0.01 — 354

4.2.3. Natural Gas Emissions By Land Use - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Land
Use
TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Govern
ment
(Civic
Center)

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 Parking
Lot

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

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Other 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 Non-Asphalt
Surfaces
Total 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 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Govern
ment
(Civic
Center)

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 Parking
Lot

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 Other
Non-Asphalt
Surfaces

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 Total 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 Annual — — — — — — — — — — — — — — — — — —
Govern
ment
(Civic
Center)

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 Parking
Lot

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 Other
Non-Asphalt
Surfaces

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 Total 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

4.3. Area Emissions by Source

4.3.1. Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Source TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e ------------------- Page 199 of 1860
East County Service Center Detailed Report, 7/8/2025
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Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Consum
er
Product
s

2.59 2.59 — — — — — — — — — — — — — — — —
Architect
ural
Coating
s

0.36 0.36 — — — — — — — — — — — — — — — —
Landsca
pe
Equipm
ent

0.93 0.86 0.04 5.22 < 0.005 0.01 — 0.01 0.01 — 0.01 — 21.5 21.5 < 0.005 < 0.005 — 21.6 Total 3.88 3.81 0.04 5.22 < 0.005 0.01 — 0.01 0.01 — 0.01 — 21.5 21.5 < 0.005 < 0.005 — 21.6 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Consum
er
Product
s

2.59 2.59 — — — — — — — — — — — — — — — —
Architect
ural
Coating
s

0.36 0.36 — — — — — — — — — — — — — — — —
Total 2.95 2.95 — — — — — — — — — — — — — — — —
Annual — — — — — — — — — — — — — — — — — —
Consum
er
Product
s

0.47 0.47 — — — — — — — — — — — — — — — —
Architect
ural
Coating
s

0.07 0.07 — — — — — — — — — — — — — — — —

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Landsca 0.08 0.08 < 0.005 0.47 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 1.75 1.75 < 0.005 < 0.005 — 1.76 pe
Total 0.62 0.62 < 0.005 0.47 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 1.75 1.75 < 0.005 < 0.005 — 1.76

4.4. Water Emissions by Land Use

4.4.1. Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Land
Use
TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Govern
ment
(Civic
Center)
— — — — — — — — — — — 45.7 87.2 133 4.70 0.11 — 284
Parking
Lot
— — — — — — — — — — — 0.00 0.00 0.00 0.00 0.00 — 0.00
Other
Non-Asphalt
Surfaces
— — — — — — — — — — — 0.00 0.00 0.00 0.00 0.00 — 0.00
Total — — — — — — — — — — — 45.7 87.2 133 4.70 0.11 — 284 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Govern
ment
(Civic
Center)
— — — — — — — — — — — 45.7 87.2 133 4.70 0.11 — 284
Parking
Lot
— — — — — — — — — — — 0.00 0.00 0.00 0.00 0.00 — 0.00
Other
Non-Asphalt
Surfaces
— — — — — — — — — — — 0.00 0.00 0.00 0.00 0.00 — 0.00

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Total — — — — — — — — — — — 45.7 87.2 133 4.70 0.11 — 284 Annual — — — — — — — — — — — — — — — — — —
Govern
ment
(Civic
Center)
— — — — — — — — — — — 7.56 14.4 22.0 0.78 0.02 — 47.0
Parking
Lot
— — — — — — — — — — — 0.00 0.00 0.00 0.00 0.00 — 0.00
Other
Non-Asphalt
Surfaces
— — — — — — — — — — — 0.00 0.00 0.00 0.00 0.00 — 0.00
Total — — — — — — — — — — — 7.56 14.4 22.0 0.78 0.02 — 47.0

4.5. Waste Emissions by Land Use

4.5.1. Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Land
Use
TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Govern
ment
(Civic
Center)
— — — — — — — — — — — 369 0.00 369 36.8 0.00 — 1,290
Parking
Lot
— — — — — — — — — — — 0.00 0.00 0.00 0.00 0.00 — 0.00
Other
Non-Asphalt
Surfaces
— — — — — — — — — — — 0.00 0.00 0.00 0.00 0.00 — 0.00
Total — — — — — — — — — — — 369 0.00 369 36.8 0.00 — 1,290 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —

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Govern
(Civic
Center)
— — — — — — — — — — — 369 0.00 369 36.8 0.00 — 1,290
Parking
Lot
— — — — — — — — — — — 0.00 0.00 0.00 0.00 0.00 — 0.00
Other
Non-Asphalt
Surfaces
— — — — — — — — — — — 0.00 0.00 0.00 0.00 0.00 — 0.00
Total — — — — — — — — — — — 369 0.00 369 36.8 0.00 — 1,290 Annual — — — — — — — — — — — — — — — — — —
Govern
ment
(Civic
Center)
— — — — — — — — — — — 61.0 0.00 61.0 6.10 0.00 — 214
Parking
Lot
— — — — — — — — — — — 0.00 0.00 0.00 0.00 0.00 — 0.00
Other
Non-Asphalt
Surfaces
— — — — — — — — — — — 0.00 0.00 0.00 0.00 0.00 — 0.00
Total — — — — — — — — — — — 61.0 0.00 61.0 6.10 0.00 — 214

4.6. Refrigerant Emissions by Land Use

4.6.1. Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Land
Use
TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Govern
ment
(Civic
Center)
— — — — — — — — — — — — — — — — 0.29 0.29
Total — — — — — — — — — — — — — — — — 0.29 0.29 Page 203 of 1860 East County Service Center Detailed Report, 7/8/2025
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Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Govern
ment
(Civic
Center)
— — — — — — — — — — — — — — — — 0.29 0.29
Total — — — — — — — — — — — — — — — — 0.29 0.29
Annual — — — — — — — — — — — — — — — — — —
Govern
ment
(Civic
Center)
— — — — — — — — — — — — — — — — 0.05 0.05
Total — — — — — — — — — — — — — — — — 0.05 0.05

4.7. Offroad Emissions By Equipment Type

4.7.1. Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Equipm
ent
Type
TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Total — — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Total — — — — — — — — — — — — — — — — — —
Annual — — — — — — — — — — — — — — — — — —
Total — — — — — — — — — — — — — — — — — —

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4.8. Stationary Emissions By Equipment Type

4.8.1. Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Equipm
ent
Type
TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Emerge
ncy
Generat
or

0.04 0.04 0.08 0.70 < 0.005 < 0.005 0.00 < 0.005 < 0.005 0.00 < 0.005 0.00 141 141 0.01 < 0.005 0.00 141 Total 0.04 0.04 0.08 0.70 < 0.005 < 0.005 0.00 < 0.005 < 0.005 0.00 < 0.005 0.00 141 141 0.01 < 0.005 0.00 141 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Emerge
ncy
Generat
or

0.04 0.04 0.08 0.70 < 0.005 < 0.005 0.00 < 0.005 < 0.005 0.00 < 0.005 0.00 141 141 0.01 < 0.005 0.00 141 Total 0.04 0.04 0.08 0.70 < 0.005 < 0.005 0.00 < 0.005 < 0.005 0.00 < 0.005 0.00 141 141 0.01 < 0.005 0.00 141 Annual — — — — — — — — — — — — — — — — — —
Emerge
ncy
Generat
or
< 0.005 < 0.005 0.01 0.08 < 0.005 < 0.005 0.00 < 0.005 < 0.005 0.00 < 0.005 0.00 13.8 13.8 < 0.005 < 0.005 0.00 13.8 Total < 0.005 < 0.005 0.01 0.08 < 0.005 < 0.005 0.00 < 0.005 < 0.005 0.00 < 0.005 0.00 13.8 13.8 < 0.005 < 0.005 0.00 13.8

4.9. User Defined Emissions By Equipment Type

4.9.1. Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Page 205 of 1860 East County Service Center Detailed Report, 7/8/2025
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Equipm
Type
TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Total — — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Total — — — — — — — — — — — — — — — — — —
Annual — — — — — — — — — — — — — — — — — —
Total — — — — — — — — — — — — — — — — — —

4.10. Soil Carbon Accumulation By Vegetation Type

4.10.1. Soil Carbon Accumulation By Vegetation Type - Unmitigated Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Vegetati
on
TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Total — — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Total — — — — — — — — — — — — — — — — — —
Annual — — — — — — — — — — — — — — — — — —
Total — — — — — — — — — — — — — — — — — —

4.10.2. Above and Belowground Carbon Accumulation by Land Use Type - Unmitigated Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Page 206 of 1860 East County Service Center Detailed Report, 7/8/2025
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Land
Use
TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Total — — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Total — — — — — — — — — — — — — — — — — —
Annual — — — — — — — — — — — — — — — — — —
Total — — — — — — — — — — — — — — — — — —

4.10.3. Avoided and Sequestered Emissions by Species - Unmitigated Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Species TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Avoided — — — — — — — — — — — — — — — — — —
Subtotal — — — — — — — — — — — — — — — — — —
Sequest
ered
— — — — — — — — — — — — — — — — — —
Subtotal — — — — — — — — — — — — — — — — — —
Remove
d
— — — — — — — — — — — — — — — — — —
Subtotal — — — — — — — — — — — — — — — — — —
— — — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Avoided — — — — — — — — — — — — — — — — — —
-------------------

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Subtotal — — — — — — — — — — — — — — — — — —
Sequest
ered
— — — — — — — — — — — — — — — — — —
Subtotal — — — — — — — — — — — — — — — — — —
Remove
d
— — — — — — — — — — — — — — — — — —
Subtotal — — — — — — — — — — — — — — — — — —
— — — — — — — — — — — — — — — — — — —
Annual — — — — — — — — — — — — — — — — — —
Avoided — — — — — — — — — — — — — — — — — —
Subtotal — — — — — — — — — — — — — — — — — —
Sequest
ered
— — — — — — — — — — — — — — — — — —
Subtotal — — — — — — — — — — — — — — — — — —
Remove
d
— — — — — — — — — — — — — — — — — —
Subtotal — — — — — — — — — — — — — — — — — —
— — — — — — — — — — — — — — — — — — —

5. Activity Data

5.1. Construction Schedule
Phase Name Phase Type Start Date End Date Days Per Week Work Days per Phase Phase Description Demolition Demolition 9/14/2026 10/14/2026 5.00 23.0 —
Site Preparation Site Preparation 10/15/2026 12/15/2026 5.00 44.0 — Grading Grading 12/16/2026 2/16/2027 5.00 45.0 —
Building Construction Building Construction 2/17/2027 10/17/2027 5.00 173 — Paving Paving 10/18/2027 12/18/2027 5.00 45.0 —
Architectural Coating Architectural Coating 8/18/2027 12/18/2027 5.00 88.0 —

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5.2. Off-Road Equipment

5.2.1. Unmitigated
Phase Name Equipment Type Fuel Type Engine Tier Number per Day Hours Per Day Horsepower Load Factor Demolition Rubber Tired Dozers Diesel Average 2.00 8.00 367 0.40 Demolition Concrete/Industrial
Saws
Diesel Average 1.00 8.00 33.0 0.73
Demolition Excavators Diesel Average 3.00 8.00 36.0 0.38 Site Preparation Rubber Tired Dozers Diesel Average 3.00 8.00 367 0.40 Site Preparation Tractors/Loaders/Back
hoes
Diesel Average 4.00 8.00 84.0 0.37
Grading Graders Diesel Average 1.00 8.00 148 0.41
Grading Excavators Diesel Average 1.00 8.00 36.0 0.38
Grading Tractors/Loaders/Back
hoes
Diesel Average 3.00 8.00 84.0 0.37
Grading Rubber Tired Dozers Diesel Average 1.00 8.00 367 0.40 Building Construction Cranes Diesel Average 1.00 7.00 367 0.29 Building Construction Forklifts Diesel Average 3.00 8.00 82.0 0.20 Building Construction Generator Sets Diesel Average 1.00 8.00 14.0 0.74 Building Construction Welders Diesel Average 1.00 8.00 46.0 0.45 Building Construction Tractors/Loaders/Back
hoes
Diesel Average 3.00 7.00 84.0 0.37
Paving Pavers Diesel Average 2.00 8.00 81.0 0.42
Paving Paving Equipment Diesel Average 2.00 8.00 89.0 0.36 Paving Rollers Diesel Average 2.00 8.00 36.0 0.38
Architectural Coating Air Compressors Diesel Average 1.00 6.00 37.0 0.48

5.3. Construction Vehicles

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5.3.1. Unmitigated
Phase Name Trip Type One-Way Trips per Day Miles per Trip Vehicle Mix Demolition — — — —
Demolition Worker 15.0 11.7 LDA,LDT1,LDT2
Demolition Vendor — 8.40 HHDT,MHDT
Demolition Hauling 94.3 20.0 HHDT
Demolition Onsite truck 15.0 0.20 HHDT
Site Preparation — — — —
Site Preparation Worker 17.5 11.7 LDA,LDT1,LDT2
Site Preparation Vendor — 8.40 HHDT,MHDT
Site Preparation Hauling 0.00 20.0 HHDT
Site Preparation Onsite truck 17.5 0.20 HHDT
Grading — — — —
Grading Worker 15.0 11.7 LDA,LDT1,LDT2
Grading Vendor — 8.40 HHDT,MHDT
Grading Hauling 16.7 20.0 HHDT
Grading Onsite truck 15.0 0.20 HHDT
Building Construction — — — —
Building Construction Worker 38.4 11.7 LDA,LDT1,LDT2
Building Construction Vendor 19.7 8.40 HHDT,MHDT
Building Construction Hauling 0.00 20.0 HHDT
Building Construction Onsite truck 58.1 0.20 HHDT
Paving — — — —
Paving Worker 15.0 11.7 LDA,LDT1,LDT2
Paving Vendor — 8.40 HHDT,MHDT
Paving Hauling 0.00 20.0 HHDT
Paving Onsite truck 15.0 0.20 HHDT
Architectural Coating — — — — Page 210 of 1860
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Architectural Coating Worker 7.68 11.7 LDA,LDT1,LDT2
Architectural Coating Vendor — 8.40 HHDT,MHDT
Architectural Coating Hauling 0.00 20.0 HHDT
Architectural Coating Onsite truck 7.70 0.20 HHDT

5.4. Vehicles

5.4.1. Construction Vehicle Control Strategies
Control Strategies Applied PM10 Reduction PM2.5 Reduction Water unpaved roads twice daily 55% 55%
Limit vehicle speeds on unpaved roads to 25 mph 44% 44% Sweep paved roads once per month 9% 9%

5.5. Architectural Coatings
Phase Name Residential Interior Area
Coated (sq ft)
Residential Exterior Area
Coated (sq ft)
Non-Residential Interior Area
Coated (sq ft)
Non-Residential Exterior Area
Coated (sq ft)
Parking Area Coated (sq ft)
Architectural Coating 0.00 0.00 180,116 60,039 16,178

5.6. Dust Mitigation

5.6.1. Construction Earthmoving Activities
Phase Name Material Imported (cy) Material Exported (cy) Acres Graded (acres) Material Demolished (Ton of Debris)
Acres Paved (acres)
Demolition 0.00 0.00 0.00 8,677 —
Site Preparation — — 66.0 0.00 —
Grading 3,773 2,222 8.00 0.00 —
Paving 0.00 0.00 0.00 0.00 6.19

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5.6.2. Construction Earthmoving Control Strategies
Control Strategies Applied Frequency (per day) PM10 Reduction PM2.5 Reduction Water Exposed Area 2 61% 61%
Water Demolished Area 2 36% 36%

5.7. Construction Paving
Land Use Area Paved (acres) % Asphalt
Government (Civic Center) 0.00 0%
Parking Lot 3.58 100%
Other Non-Asphalt Surfaces 2.61 0%

5.8. Construction Electricity Consumption and Emissions Factors kWh per Year and Emission Factor (lb/MWh)
Year kWh per Year CO2 CH4 N2O
2027 393,165 204 0.03 < 0.005
2026 393,165 204 0.03 < 0.005

5.9. Operational Mobile Sources

5.9.1. Unmitigated
Land Use Type Trips/Weekday Trips/Saturday Trips/Sunday Trips/Year VMT/Weekday VMT/Saturday VMT/Sunday VMT/Year Government (Civic
Center)
3,285 0.00 0.00 856,446 17,147 0.00 0.00 4,470,526
Parking Lot 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
Other Non-Asphalt
Surfaces

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

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5.10. Operational Area Sources

5.10.1. Hearths

5.10.1.1. Unmitigated

5.10.2. Architectural Coatings
Residential Interior Area Coated (sq
ft)
Residential Exterior Area Coated (sq
ft)
Non-Residential Interior Area Coated
(sq ft)
Non-Residential Exterior Area
Coated (sq ft)
Parking Area Coated (sq ft)
0 0.00 180,116 60,039 16,178

5.10.3. Landscape Equipment
Season Unit Value
Snow Days day/yr 0.00
Summer Days day/yr 180

5.11. Operational Energy Consumption

5.11.1. Unmitigated
Electricity (kWh/yr) and CO2 and CH4 and N2O and Natural Gas (kBTU/yr) Land Use Electricity (kWh/yr) CO2 CH4 N2O Natural Gas (kBTU/yr) Government (Civic Center) 3,651,738 204 0.0330 0.0040 0.00 Parking Lot 136,608 204 0.0330 0.0040 0.00
Other Non-Asphalt Surfaces 0.00 204 0.0330 0.0040 0.00

5.12. Operational Water and Wastewater Consumption

5.12.1. Unmitigated
Land Use Indoor Water (gal/year) Outdoor Water (gal/year) Page 213 of 1860 East County Service Center Detailed Report, 7/8/2025
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Government (Civic Center) 23,839,162 336,416
Parking Lot 0.00 0.00
Other Non-Asphalt Surfaces 0.00 0.00

5.13. Operational Waste Generation

5.13.1. Unmitigated
Land Use Waste (ton/year) Cogeneration (kWh/year)
Government (Civic Center) 684 —
Parking Lot 0.00 —
Other Non-Asphalt Surfaces 0.00 —

5.14. Operational Refrigeration and Air Conditioning Equipment

5.14.1. Unmitigated
Land Use Type Equipment Type Refrigerant GWP Quantity (kg) Operations Leak Rate Service Leak Rate Times Serviced Government (Civic
Center)
Household
refrigerators and/or
freezers
R-134a 1,430 0.02 0.60 0.00 1.00
Government (Civic
Center)
Other commercial A/C
and heat pumps
R-410A 2,088 < 0.005 4.00 4.00 18.0

5.15. Operational Off-Road Equipment

5.15.1. Unmitigated
Equipment Type Fuel Type Engine Tier Number per Day Hours Per Day Horsepower Load Factor

5.16. Stationary Sources

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5.16.1. Emergency Generators and Fire Pumps
Equipment Type Fuel Type Number per Day Hours per Day Hours per Year Horsepower Load Factor Emergency Generator Diesel 1.00 0.50 108 335 0.73

5.16.2. Process Boilers
Equipment Type Fuel Type Number Boiler Rating (MMBtu/hr) Daily Heat Input (MMBtu/day) Annual Heat Input (MMBtu/yr)

5.17. User Defined
Equipment Type Fuel Type

5.18. Vegetation

5.18.1. Land Use Change

5.18.1.1. Unmitigated
Vegetation Land Use Type Vegetation Soil Type Initial Acres Final Acres

5.18.1. Biomass Cover Type

5.18.1.1. Unmitigated
Biomass Cover Type Initial Acres Final Acres

5.18.2. Sequestration

5.18.2.1. Unmitigated
Tree Type Number Electricity Saved (kWh/year) Natural Gas Saved (btu/year)

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6. Climate Risk Detailed Report

6.1. Climate Risk Summary
Cal-Adapt midcentury 2040–2059 average projections for four hazards are reported below for your project location. These are under Representation Concentration Pathway (RCP) 8.5 which assumes GHG emissions will continue to rise strongly through 2050 and then plateau around 2100.

Climate Hazard Result for Project Location Unit
Temperature and Extreme Heat 19.3 annual days of extreme heat Extreme Precipitation 2.10 annual days with precipitation above 20 mm Sea Level Rise — meters of inundation depth
Wildfire 8.54 annual hectares burned
Temperature and Extreme Heat data are for grid cell in which your project are located. The projection is based on the 98th historical percentile of daily maximum/minimum temperatures from observed historical data (32 climate model ensemble from Cal-Adapt, 2040–2059 average under RCP 8.5). Each grid cell is 6 kilometers (km) by 6 km, or 3.7 miles (mi) by 3.7 mi.

Extreme Precipitation data are for the grid cell in which your project are located. The threshold of 20 mm is equivalent to about ¾ an inch of rain, which would be light to moderate rainfall if received over a full day or heavy rain if received over a period of 2 to 4 hours. Each grid cell is 6 kilometers (km) by 6 km, or 3.7 miles (mi) by 3.7 mi.

Sea Level Rise data are for the grid cell in which your project are located. The projections are from Radke et al. (2017), as reported in Cal-Adapt (Radke et al., 2017, CEC-500-2017-008), and consider inundation location and depth for the San Francisco Bay, the Sacramento-San Joaquin River Delta and California coast resulting different increments of sea level rise coupled with extreme storm events. Users may select from four scenarios to view the range in potential inundation depth for the grid cell. The four scenarios are: No rise, 0.5 meter, 1.0 meter, 1.41 meters Wildfire data are for the grid cell in which your project are located. The projections are from UC Davis, as reported in Cal-Adapt (2040–2059 average under RCP 8.5), and consider historical data of climate, vegetation, population density, and large (> 400 ha) fire history. Users may select from four model simulations to view the range in potential wildfire probabilities for the grid cell. The four simulations make different assumptions about expected rainfall and temperature are: Warmer/drier (HadGEM2-ES), Cooler/wetter (CNRM-CM5), Average conditions (CanESM2), Range of different rainfall and temperature possibilities (MIROC5). Each grid cell is 6 kilometers (km) by 6 km, or 3.7 miles (mi) by 3.7 mi.

6.2. Initial Climate Risk Scores
Climate Hazard Exposure Score Sensitivity Score Adaptive Capacity Score Vulnerability Score Temperature and Extreme Heat N/A N/A N/A N/A
Extreme Precipitation 1 0 0 N/A
Sea Level Rise 1 0 0 N/A
Wildfire 1 0 0 N/A
Flooding N/A N/A N/A N/A
Drought N/A N/A N/A N/A
Snowpack Reduction N/A N/A N/A N/A
Air Quality Degradation 0 0 0 N/A Page 216 of 1860
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The sensitivity score reflects the extent to which a project would be adversely affected by exposure to a climate hazard. Exposure is rated on a scale of 1 to 5, with a score of 5 representing the greatest exposure.

The adaptive capacity of a project refers to its ability to manage and reduce vulnerabilities from projected climate hazards. Adaptive capacity is rated on a scale of 1 to 5, with a score of 5 representing the greatest ability to adapt.

The overall vulnerability scores are calculated based on the potential impacts and adaptive capacity assessments for each hazard. Scores do not include implementation of climate risk reduction measures.

6.3. Adjusted Climate Risk Scores
Climate Hazard Exposure Score Sensitivity Score Adaptive Capacity Score Vulnerability Score Temperature and Extreme Heat N/A N/A N/A N/A
Extreme Precipitation 1 1 1 2
Sea Level Rise 1 1 1 2
Wildfire 1 1 1 2
Flooding N/A N/A N/A N/A
Drought N/A N/A N/A N/A
Snowpack Reduction N/A N/A N/A N/A
Air Quality Degradation 1 1 1 2
The sensitivity score reflects the extent to which a project would be adversely affected by exposure to a climate hazard. Exposure is rated on a scale of 1 to 5, with a score of 5 representing the greatest exposure.

The adaptive capacity of a project refers to its ability to manage and reduce vulnerabilities from projected climate hazards. Adaptive capacity is rated on a scale of 1 to 5, with a score of 5 representing the greatest ability to adapt.

The overall vulnerability scores are calculated based on the potential impacts and adaptive capacity assessments for each hazard. Scores include implementation of climate risk reduction measures.

6.4. Climate Risk Reduction Measures

7. Health and Equity Details

7.1. CalEnviroScreen 4.0 Scores
The maximum CalEnviroScreen score is 100. A high score (i.e., greater than 50) reflects a higher pollution burden compared to other census tracts in the state.

Indicator Result for Project Census Tract
Exposure Indicators —
AQ-Ozone 37.6

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AQ-PM 29.3
AQ-DPM 56.3
Drinking Water 57.6
Lead Risk Housing 24.5
Pesticides 42.9
Toxic Releases 29.1
Traffic 17.0
Effect Indicators —
CleanUp Sites 88.5
Groundwater 40.8
Haz Waste Facilities/Generators 44.7
Impaired Water Bodies 77.3
Solid Waste 22.1
Sensitive Population —
Asthma 62.3
Cardio-vascular 64.2
Low Birth Weights 42.8
Socioeconomic Factor Indicators —
Education 41.9
Housing 29.7
Linguistic —
Poverty 35.4
Unemployment 53.9

7.2. Healthy Places Index Scores
The maximum Health Places Index score is 100. A high score (i.e., greater than 50) reflects healthier community conditions compared to other census tracts in the state.

Indicator Result for Project Census Tract
Economic —

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Above Poverty 62.79994867
Employed 78.07006288
Median HI 87.29629154
Education —
Bachelor's or higher 53.83036058
High school enrollment 19.62017195
Preschool enrollment 39.0606955
Transportation —
Auto Access 96.70216861
Active commuting 41.72975747
Social —
2-parent households 82.75375337
Voting 61.17028102
Neighborhood —
Alcohol availability 58.88617991
Park access 49.22366226
Retail density 25.47157706
Supermarket access 33.37610676
Tree canopy 68.71551392
Housing —
Homeownership 75.52932119
Housing habitability 63.98049532
Low-inc homeowner severe housing cost burden 41.3832927 Low-inc renter severe housing cost burden 55.34453997
Uncrowded housing 33.53009111
Health Outcomes —
Insured adults 70.40934172
Arthritis 0.0

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Asthma ER Admissions 32.0
High Blood Pressure 0.0
Cancer (excluding skin) 0.0
Asthma 0.0
Coronary Heart Disease 0.0
Chronic Obstructive Pulmonary Disease 0.0
Diagnosed Diabetes 0.0
Life Expectancy at Birth 32.3
Cognitively Disabled 46.5
Physically Disabled 65.4
Heart Attack ER Admissions 14.9
Mental Health Not Good 0.0
Chronic Kidney Disease 0.0
Obesity 0.0
Pedestrian Injuries 43.8
Physical Health Not Good 0.0
Stroke 0.0
Health Risk Behaviors—
Binge Drinking 0.0
Current Smoker 0.0
No Leisure Time for Physical Activity 0.0
Climate Change Exposures—
Wildfire Risk 0.0
SLR Inundation Area 0.0
Children 14.1
Elderly 70.0
English Speaking 85.7
Foreign-born 51.0

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Outdoor Workers 23.6
Climate Change Adaptive Capacity —
Impervious Surface Cover 58.1
Traffic Density 27.0
Traffic Access 52.6
Other Indices —
Hardship 43.9
Other Decision Support —
2016 Voting 51.7

7.3. Overall Health & Equity Scores
Metric Result for Project Census Tract
CalEnviroScreen 4.0 Score for Project Location (a) 51.0 Healthy Places Index Score for Project Location (b) 74.0 Project Located in a Designated Disadvantaged Community (Senate Bill 535) No Project Located in a Low-Income Community (Assembly Bill 1550) No Project Located in a Community Air Protection Program Community (Assembly Bill 617) No a: The maximum CalEnviroScreen score is 100. A high score (i.e., greater than 50) reflects a higher pollution burden compared to other census tracts in the state. b: The maximum Health Places Index score is 100. A high score (i.e., greater than 50) reflects healthier community conditions compared to other census tracts in the state.

7.4. Health & Equity Measures
No Health & Equity Measures selected.

7.5. Evaluation Scorecard
Health & Equity Evaluation Scorecard not completed.

7.6. Health & Equity Custom Measures
No Health & Equity Custom Measures created.

8. User Changes to Default Data

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Screen Justification
Land Use Consistent with Project Description.

Construction: Construction Phases Consistent with Project Description.

Construction: Dust From Material Movement Provided by project sponsor.

Construction: Paving Consistent with site plans/concept estimate.

Construction: On-Road Fugitive Dust Updated mean vehicle speed per BAAQMD guidance.

Operations: Energy Use Updated to account for all-electric end uses.

Operations: Emergency Generators and Fire Pumps Emergency generator parameters consistent with BAAQMD guidance.

Construction: Demolition Added demo for site prep.

Construction: Electricity Estimated electricity use.

Construction: Off-Road Equipment fd
Operations: Vehicle Data Consistent with TIS.

Operations: Generators + Pumps EF Updated emission factors to account for BAAQMD TBACT.

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East County Service Center - MIT Detailed Report
Table of Contents

1. Basic Project Information

1.1. Basic Project Information

1.2. Land Use Types

1.3. User-Selected Emission Reduction Measures by Emissions Sector

2. Emissions Summary

2.1. Construction Emissions Compared Against Thresholds

2.2. Construction Emissions by Year, Unmitigated

2.3. Construction Emissions by Year, Mitigated

2.4. Operations Emissions Compared Against Thresholds

2.5. Operations Emissions by Sector, Unmitigated

2.6. Operations Emissions by Sector, Mitigated

3. Construction Emissions Details

3.1. Demolition (2026) - Unmitigated

3.2. Demolition (2026) - Mitigated

3.3. Site Preparation (2026) - Unmitigated

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3.4. Site Preparation (2026) - Mitigated

3.5. Grading (2026) - Unmitigated

3.6. Grading (2026) - Mitigated

3.7. Grading (2027) - Unmitigated

3.8. Grading (2027) - Mitigated

3.9. Building Construction (2027) - Unmitigated

3.10. Building Construction (2027) - Mitigated

3.11. Paving (2027) - Unmitigated

3.12. Paving (2027) - Mitigated

3.13. Architectural Coating (2027) - Unmitigated

3.14. Architectural Coating (2027) - Mitigated

4. Operations Emissions Details

4.1. Mobile Emissions by Land Use

4.1.1. Unmitigated

4.1.2. Mitigated

4.2. Energy

4.2.1. Electricity Emissions By Land Use - Unmitigated

4.2.2. Electricity Emissions By Land Use - Mitigated

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4.2.3. Natural Gas Emissions By Land Use - Unmitigated

4.2.4. Natural Gas Emissions By Land Use - Mitigated

4.3. Area Emissions by Source

4.3.1. Unmitigated

4.3.2. Mitigated

4.4. Water Emissions by Land Use

4.4.1. Unmitigated

4.4.2. Mitigated

4.5. Waste Emissions by Land Use

4.5.1. Unmitigated

4.5.2. Mitigated

4.6. Refrigerant Emissions by Land Use

4.6.1. Unmitigated

4.6.2. Mitigated

4.7. Offroad Emissions By Equipment Type

4.7.1. Unmitigated

4.7.2. Mitigated

4.8. Stationary Emissions By Equipment Type

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4.8.1. Unmitigated

4.8.2. Mitigated

4.9. User Defined Emissions By Equipment Type

4.9.1. Unmitigated

4.9.2. Mitigated

4.10. Soil Carbon Accumulation By Vegetation Type

4.10.1. Soil Carbon Accumulation By Vegetation Type - Unmitigated

4.10.2. Above and Belowground Carbon Accumulation by Land Use Type - Unmitigated

4.10.3. Avoided and Sequestered Emissions by Species - Unmitigated

4.10.4. Soil Carbon Accumulation By Vegetation Type - Mitigated

4.10.5. Above and Belowground Carbon Accumulation by Land Use Type - Mitigated

4.10.6. Avoided and Sequestered Emissions by Species - Mitigated

5. Activity Data

5.1. Construction Schedule

5.2. Off-Road Equipment

5.2.1. Unmitigated

5.2.2. Mitigated

5.3. Construction Vehicles

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5.3.1. Unmitigated

5.3.2. Mitigated

5.4. Vehicles

5.4.1. Construction Vehicle Control Strategies

5.5. Architectural Coatings

5.6. Dust Mitigation

5.6.1. Construction Earthmoving Activities

5.6.2. Construction Earthmoving Control Strategies

5.7. Construction Paving

5.8. Construction Electricity Consumption and Emissions Factors

5.9. Operational Mobile Sources

5.9.1. Unmitigated

5.9.2. Mitigated

5.10. Operational Area Sources

5.10.1. Hearths

5.10.1.1. Unmitigated

5.10.1.2. Mitigated

5.10.2. Architectural Coatings

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5.10.3. Landscape Equipment

5.10.4. Landscape Equipment - Mitigated

5.11. Operational Energy Consumption

5.11.1. Unmitigated

5.11.2. Mitigated

5.12. Operational Water and Wastewater Consumption

5.12.1. Unmitigated

5.12.2. Mitigated

5.13. Operational Waste Generation

5.13.1. Unmitigated

5.13.2. Mitigated

5.14. Operational Refrigeration and Air Conditioning Equipment

5.14.1. Unmitigated

5.14.2. Mitigated

5.15. Operational Off-Road Equipment

5.15.1. Unmitigated

5.15.2. Mitigated

5.16. Stationary Sources

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5.16.1. Emergency Generators and Fire Pumps

5.16.2. Process Boilers

5.17. User Defined

5.18. Vegetation

5.18.1. Land Use Change

5.18.1.1. Unmitigated

5.18.1.2. Mitigated

5.18.1. Biomass Cover Type

5.18.1.1. Unmitigated

5.18.1.2. Mitigated

5.18.2. Sequestration

5.18.2.1. Unmitigated

5.18.2.2. Mitigated

6. Climate Risk Detailed Report

6.1. Climate Risk Summary

6.2. Initial Climate Risk Scores

6.3. Adjusted Climate Risk Scores

6.4. Climate Risk Reduction Measures

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7. Health and Equity Details

7.1. CalEnviroScreen 4.0 Scores

7.2. Healthy Places Index Scores

7.3. Overall Health & Equity Scores

7.4. Health & Equity Measures

7.5. Evaluation Scorecard

7.6. Health & Equity Custom Measures

8. User Changes to Default Data

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1. Basic Project Information

1.1. Basic Project Information
Data Field Value
Project Name East County Service Center - MIT
Construction Start Date 3/15/2027
Operational Year 2029
Lead Agency —
Land Use Scale Project/site
Analysis Level for Defaults County
Windspeed (m/s) 3.00
Precipitation (days) 20.6
Location Technology Way, Brentwood, CA 94513, USA
County Contra Costa
City Brentwood
Air District Bay Area AQMD
Air Basin San Francisco Bay Area
TAZ 1363
EDFZ 1
Electric Utility Pacific Gas & Electric Company
Gas Utility Pacific Gas & Electric
App Version 2022.1.1.29

1.2. Land Use Types
Land Use Subtype Size Unit Lot Acreage Building Area (sq ft) Landscape Area (sq ft)
Special Landscape
Area (sq ft)
Population Description
Government (Civic
Center)
120 1000sqft 0.87 120,077 28,187 — — —

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Parking Lot 424 Space 3.58 0.00 0.00 — — —
Other Non-Asphalt
Surfaces

2.61 Acre 2.61 0.00 0.00 — — —

1.3. User-Selected Emission Reduction Measures by Emissions Sector Sector # Measure Title
Construction C-5 Use Advanced Engine Tiers

2. Emissions Summary

2.1. Construction Emissions Compared Against Thresholds Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Un/Mit. TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Unmit. 16.7 16.4 29.2 23.8 0.08 0.97 12.4 13.4 0.86 2.51 3.37 — 11,233 11,233 0.84 1.12 14.3 11,603 Mit. 15.8 15.6 13.0 22.9 0.08 0.19 12.4 12.6 0.15 2.51 2.66 — 11,233 11,233 0.84 1.12 14.3 11,603 %
Reduced
6% 5% 55% 4% — 81% — 6% 83% — 21% — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Unmit. 16.7 16.4 29.6 29.6 0.08 1.24 12.4 13.4 1.14 2.85 4.00 — 11,225 11,225 0.84 1.12 0.37 11,581 Mit. 15.7 15.6 13.4 29.1 0.08 0.19 12.4 12.6 0.15 2.85 2.95 — 11,225 11,225 0.84 1.12 0.37 11,581 %
Reduced
6% 5% 55% 2% — 85% — 6% 87% — 26% — — — — — — —
Average
Daily
(Max)
— — — — — — — — — — — — — — — — — —
Unmit. 4.71 4.51 7.81 10.5 0.02 0.26 2.68 2.94 0.24 0.54 0.75 — 2,452 2,452 0.15 0.09 0.62 2,483 -------------------

East County Service Center - MIT Detailed Report, 7/8/2025 11 / 85
Mit. 4.03 3.97 2.91 11.5 0.02 0.05 2.68 2.73 0.05 0.54 0.57 — 2,452 2,452 0.15 0.09 0.62 2,483 %
Reduced
14% 12% 63% -9% — 81% — 7% 80% — 25% — — — — — — —
Annual
(Max)
— — — — — — — — — — — — — — — — — —
Unmit. 0.86 0.82 1.42 1.91 < 0.005 0.05 0.49 0.54 0.04 0.10 0.14 — 406 406 0.02 0.01 0.10 411 Mit. 0.74 0.72 0.53 2.09 < 0.005 0.01 0.49 0.50 0.01 0.10 0.10 — 406 406 0.02 0.01 0.10 411 %
Reduced
14% 12% 63% -9% — 81% — 7% 80% — 25% — — — — — — —

2.2. Construction Emissions by Year, Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Year TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily -
Summer
(Max)
— — — — — — — — — — — — — — — — — —
2026 3.47 2.49 29.2 23.8 0.08 0.97 12.4 13.4 0.86 2.51 3.37 — 11,233 11,233 0.84 1.12 14.3 11,603 2027 16.7 16.4 11.9 16.8 0.03 0.36 5.06 5.43 0.34 0.81 1.15 — 3,819 3,819 0.22 0.14 2.53 3,869 Daily -
Winter
(Max)
— — — — — — — — — — — — — — — — — —
2026 3.82 3.21 29.6 29.6 0.08 1.24 12.4 13.4 1.14 2.85 4.00 — 11,225 11,225 0.84 1.12 0.37 11,581 2027 16.7 16.4 16.0 18.6 0.04 0.61 5.06 5.43 0.56 1.35 1.92 — 4,491 4,491 0.26 0.22 0.07 4,563 Average
Daily
— — — — — — — — — — — — — — — — — —
2026 0.75 0.60 5.93 5.64 0.01 0.23 1.68 1.91 0.21 0.54 0.75 — 1,657 1,657 0.11 0.09 0.46 1,687 2027 4.71 4.51 7.81 10.5 0.02 0.26 2.68 2.94 0.24 0.50 0.74 — 2,452 2,452 0.15 0.09 0.62 2,483 Annual — — — — — — — — — — — — — — — — — —
2026 0.14 0.11 1.08 1.03 < 0.005 0.04 0.31 0.35 0.04 0.10 0.14 — 274 274 0.02 0.01 0.08 279 2027 0.86 0.82 1.42 1.91 < 0.005 0.05 0.49 0.54 0.04 0.09 0.13 — 406 406 0.02 0.01 0.10 411 -------------------

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2.3. Construction Emissions by Year, Mitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Year TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily -
Summer
(Max)
— — — — — — — — — — — — — — — — — —
2026 1.11 0.57 13.0 22.9 0.08 0.19 12.4 12.6 0.15 2.51 2.66 — 11,233 11,233 0.84 1.12 14.3 11,603 2027 15.8 15.6 5.16 18.5 0.03 0.08 5.06 5.15 0.08 0.81 0.90 — 3,819 3,819 0.22 0.14 2.53 3,869 Daily -
Winter
(Max)
— — — — — — — — — — — — — — — — — —
2026 1.10 0.56 13.4 29.1 0.08 0.19 12.4 12.6 0.15 2.85 2.95 — 11,225 11,225 0.84 1.12 0.37 11,581 2027 15.7 15.6 5.26 19.1 0.04 0.08 5.06 5.15 0.08 1.35 1.42 — 4,491 4,491 0.26 0.22 0.07 4,563 Average
Daily
— — — — — — — — — — — — — — — — — —
2026 0.15 0.11 1.31 5.54 0.01 0.03 1.68 1.70 0.02 0.54 0.57 — 1,657 1,657 0.11 0.09 0.46 1,687 2027 4.03 3.97 2.91 11.5 0.02 0.05 2.68 2.73 0.05 0.50 0.55 — 2,452 2,452 0.15 0.09 0.62 2,483 Annual — — — — — — — — — — — — — — — — — —
2026 0.03 0.02 0.24 1.01 < 0.005 < 0.005 0.31 0.31 < 0.005 0.10 0.10 — 274 274 0.02 0.01 0.08 279 2027 0.74 0.72 0.53 2.09 < 0.005 0.01 0.49 0.50 0.01 0.09 0.10 — 406 406 0.02 0.01 0.10 411

2.4. Operations Emissions Compared Against Thresholds
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Un/Mit. TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Unmit. 14.3 13.7 5.32 62.4 0.13 0.10 12.1 12.2 0.09 3.07 3.16 414 15,464 15,879 42.5 0.73 34.2 17,193 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
-------------------
-------------------

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Unmit. 12.9 12.2 6.21 56.9 0.12 0.09 12.1 12.2 0.08 3.07 3.15 414 14,573 14,987 42.7 0.79 1.17 16,291 Average
Daily
(Max)
— — — — — — — — — — — — — — — — — —
Unmit. 10.4 9.95 4.16 40.9 0.09 0.07 8.53 8.60 0.06 2.16 2.22 414 11,103 11,517 42.4 0.59 10.7 12,764 Annual
(Max)
— — — — — — — — — — — — — — — — — —
Unmit. 1.90 1.82 0.76 7.46 0.02 0.01 1.56 1.57 0.01 0.39 0.41 68.6 1,838 1,907 7.02 0.10 1.78 2,113

2.5. Operations Emissions by Sector, Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Sector TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Mobile 10.4 9.86 5.20 56.5 0.13 0.08 12.1 12.2 0.08 3.07 3.15 — 13,098 13,098 0.65 0.57 33.9 13,319 Area 3.88 3.81 0.04 5.22 < 0.005 0.01 — 0.01 0.01 — 0.01 — 21.5 21.5 < 0.005 < 0.005 — 21.6 Energy 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 — 0.00 — 2,117 2,117 0.34 0.04 — 2,138 Water — — — — — — — — — — — 45.7 87.2 133 4.70 0.11 — 284 Waste — — — — — — — — — — — 369 0.00 369 36.8 0.00 — 1,290 Refrig. — — — — — — — — — — — — — — — — 0.29 0.29
Stationa
ry

0.04 0.04 0.08 0.70 < 0.005 < 0.005 0.00 < 0.005 < 0.005 0.00 < 0.005 0.00 141 141 0.01 < 0.005 0.00 141 Total 14.3 13.7 5.32 62.4 0.13 0.10 12.1 12.2 0.09 3.07 3.16 414 15,464 15,879 42.5 0.73 34.2 17,193 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Mobile 9.86 9.25 6.13 56.2 0.12 0.08 12.1 12.2 0.08 3.07 3.15 — 12,228 12,228 0.77 0.64 0.88 12,438 Area 2.95 2.95 — — — — — — — — — — — — — — — —
Energy 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 — 0.00 — 2,117 2,117 0.34 0.04 — 2,138 Water — — — — — — — — — — — 45.7 87.2 133 4.70 0.11 — 284 -------------------

East County Service Center - MIT Detailed Report, 7/8/2025 14 / 85
Waste — — — — — — — — — — — 369 0.00 369 36.8 0.00 — 1,290 Refrig. — — — — — — — — — — — — — — — — 0.29 0.29
Stationa
ry

0.04 0.04 0.08 0.70 < 0.005 < 0.005 0.00 < 0.005 < 0.005 0.00 < 0.005 0.00 141 141 0.01 < 0.005 0.00 141 Total 12.9 12.2 6.21 56.9 0.12 0.09 12.1 12.2 0.08 3.07 3.15 414 14,573 14,987 42.7 0.79 1.17 16,291 Average
Daily
— — — — — — — — — — — — — — — — — —
Mobile 6.97 6.55 4.10 37.9 0.09 0.06 8.53 8.59 0.06 2.16 2.22 — 8,805 8,805 0.51 0.44 10.5 8,958 Area 3.41 3.38 0.02 2.58 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 10.6 10.6 < 0.005 < 0.005 — 10.6 Energy 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 — 0.00 — 2,117 2,117 0.34 0.04 — 2,138 Water — — — — — — — — — — — 45.7 87.2 133 4.70 0.11 — 284 Waste — — — — — — — — — — — 369 0.00 369 36.8 0.00 — 1,290 Refrig. — — — — — — — — — — — — — — — — 0.29 0.29
Stationa
ry

0.02 0.02 0.05 0.41 < 0.005 < 0.005 0.00 < 0.005 < 0.005 0.00 < 0.005 0.00 83.2 83.2 < 0.005 < 0.005 0.00 83.5 Total 10.4 9.95 4.16 40.9 0.09 0.07 8.53 8.60 0.06 2.16 2.22 414 11,103 11,517 42.4 0.59 10.7 12,764 Annual — — — — — — — — — — — — — — — — — —
Mobile 1.27 1.20 0.75 6.92 0.02 0.01 1.56 1.57 0.01 0.39 0.40 — 1,458 1,458 0.08 0.07 1.73 1,483 Area 0.62 0.62 < 0.005 0.47 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 1.75 1.75 < 0.005 < 0.005 — 1.76 Energy 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 — 0.00 — 351 351 0.06 0.01 — 354 Water — — — — — — — — — — — 7.56 14.4 22.0 0.78 0.02 — 47.0 Waste — — — — — — — — — — — 61.0 0.00 61.0 6.10 0.00 — 214 Refrig. — — — — — — — — — — — — — — — — 0.05 0.05
Stationa
ry
< 0.005 < 0.005 0.01 0.08 < 0.005 < 0.005 0.00 < 0.005 < 0.005 0.00 < 0.005 0.00 13.8 13.8 < 0.005 < 0.005 0.00 13.8 Total 1.90 1.82 0.76 7.46 0.02 0.01 1.56 1.57 0.01 0.39 0.41 68.6 1,838 1,907 7.02 0.10 1.78 2,113

2.6. Operations Emissions by Sector, Mitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual)

East County Service Center - MIT Detailed Report, 7/8/2025 15 / 85
Sector TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Mobile 10.4 9.86 5.20 56.5 0.13 0.08 12.1 12.2 0.08 3.07 3.15 — 13,098 13,098 0.65 0.57 33.9 13,319 Area 3.88 3.81 0.04 5.22 < 0.005 0.01 — 0.01 0.01 — 0.01 — 21.5 21.5 < 0.005 < 0.005 — 21.6 Energy 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 — 0.00 — 2,117 2,117 0.34 0.04 — 2,138 Water — — — — — — — — — — — 45.7 87.2 133 4.70 0.11 — 284 Waste — — — — — — — — — — — 369 0.00 369 36.8 0.00 — 1,290 Refrig. — — — — — — — — — — — — — — — — 0.29 0.29
Stationa
ry

0.04 0.04 0.08 0.70 < 0.005 < 0.005 0.00 < 0.005 < 0.005 0.00 < 0.005 0.00 141 141 0.01 < 0.005 0.00 141 Total 14.3 13.7 5.32 62.4 0.13 0.10 12.1 12.2 0.09 3.07 3.16 414 15,464 15,879 42.5 0.73 34.2 17,193 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Mobile 9.86 9.25 6.13 56.2 0.12 0.08 12.1 12.2 0.08 3.07 3.15 — 12,228 12,228 0.77 0.64 0.88 12,438 Area 2.95 2.95 — — — — — — — — — — — — — — — —
Energy 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 — 0.00 — 2,117 2,117 0.34 0.04 — 2,138 Water — — — — — — — — — — — 45.7 87.2 133 4.70 0.11 — 284 Waste — — — — — — — — — — — 369 0.00 369 36.8 0.00 — 1,290 Refrig. — — — — — — — — — — — — — — — — 0.29 0.29
Stationa
ry

0.04 0.04 0.08 0.70 < 0.005 < 0.005 0.00 < 0.005 < 0.005 0.00 < 0.005 0.00 141 141 0.01 < 0.005 0.00 141 Total 12.9 12.2 6.21 56.9 0.12 0.09 12.1 12.2 0.08 3.07 3.15 414 14,573 14,987 42.7 0.79 1.17 16,291 Average
Daily
— — — — — — — — — — — — — — — — — —
Mobile 6.97 6.55 4.10 37.9 0.09 0.06 8.53 8.59 0.06 2.16 2.22 — 8,805 8,805 0.51 0.44 10.5 8,958 Area 3.41 3.38 0.02 2.58 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 10.6 10.6 < 0.005 < 0.005 — 10.6 Energy 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 — 0.00 — 2,117 2,117 0.34 0.04 — 2,138 Water — — — — — — — — — — — 45.7 87.2 133 4.70 0.11 — 284 -------------------

East County Service Center - MIT Detailed Report, 7/8/2025 16 / 85
Waste — — — — — — — — — — — 369 0.00 369 36.8 0.00 — 1,290 Refrig. — — — — — — — — — — — — — — — — 0.29 0.29
Stationa
ry

0.02 0.02 0.05 0.41 < 0.005 < 0.005 0.00 < 0.005 < 0.005 0.00 < 0.005 0.00 83.2 83.2 < 0.005 < 0.005 0.00 83.5 Total 10.4 9.95 4.16 40.9 0.09 0.07 8.53 8.60 0.06 2.16 2.22 414 11,103 11,517 42.4 0.59 10.7 12,764 Annual — — — — — — — — — — — — — — — — — —
Mobile 1.27 1.20 0.75 6.92 0.02 0.01 1.56 1.57 0.01 0.39 0.40 — 1,458 1,458 0.08 0.07 1.73 1,483 Area 0.62 0.62 < 0.005 0.47 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 1.75 1.75 < 0.005 < 0.005 — 1.76 Energy 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 — 0.00 — 351 351 0.06 0.01 — 354 Water — — — — — — — — — — — 7.56 14.4 22.0 0.78 0.02 — 47.0 Waste — — — — — — — — — — — 61.0 0.00 61.0 6.10 0.00 — 214 Refrig. — — — — — — — — — — — — — — — — 0.05 0.05
Stationa
ry
< 0.005 < 0.005 0.01 0.08 < 0.005 < 0.005 0.00 < 0.005 < 0.005 0.00 < 0.005 0.00 13.8 13.8 < 0.005 < 0.005 0.00 13.8 Total 1.90 1.82 0.76 7.46 0.02 0.01 1.56 1.57 0.01 0.39 0.41 68.6 1,838 1,907 7.02 0.10 1.78 2,113

3. Construction Emissions Details

3.1. Demolition (2026) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Onsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

2.72 2.29 20.7 19.0 0.03 0.84 — 0.84 0.78 — 0.78 — 3,427 3,427 0.14 0.03 — 3,438 Demoliti
on
— — — — — — 5.30 5.30 — 0.80 0.80 — — — — — — —
-------------------

East County Service Center - MIT Detailed Report, 7/8/2025 17 / 85
Onsite
truck

0.02 0.01 0.22 0.16 < 0.005 < 0.005 0.68 0.68 < 0.005 0.07 0.07 — 34.8 34.8 0.01 0.01 0.02 36.7 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

2.72 2.29 20.7 19.0 0.03 0.84 — 0.84 0.78 — 0.78 — 3,427 3,427 0.14 0.03 — 3,438 Demoliti
on
— — — — — — 5.30 5.30 — 0.80 0.80 — — — — — — —
Onsite
truck

0.02 0.01 0.23 0.16 < 0.005 < 0.005 0.68 0.68 < 0.005 0.07 0.07 — 35.2 35.2 0.01 0.01 < 0.005 37.1 Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.17 0.14 1.30 1.20 < 0.005 0.05 — 0.05 0.05 — 0.05 — 216 216 0.01 < 0.005 — 217 Demoliti
on
— — — — — — 0.33 0.33 — 0.05 0.05 — — — — — — —
Onsite
truck
< 0.005 < 0.005 0.01 0.01 < 0.005 < 0.005 0.04 0.04 < 0.005 < 0.005 < 0.005 — 2.20 2.20 < 0.005 < 0.005 < 0.005 2.32 Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.03 0.03 0.24 0.22 < 0.005 0.01 — 0.01 0.01 — 0.01 — 35.7 35.7 < 0.005 < 0.005 — 35.9 Demoliti
on
— — — — — — 0.06 0.06 — 0.01 0.01 — — — — — — —
Onsite
truck
< 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 0.01 0.01 < 0.005 < 0.005 < 0.005 — 0.36 0.36 < 0.005 < 0.005 < 0.005 0.38 Offsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —

East County Service Center - MIT Detailed Report, 7/8/2025 18 / 85
Worker 0.05 0.05 0.03 0.59 0.00 0.00 0.51 0.51 0.00 0.13 0.13 — 130 130 < 0.005 < 0.005 0.48 132 Vendor 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 0.00 Hauling 0.67 0.14 8.27 4.00 0.04 0.12 5.91 6.03 0.08 1.52 1.60 — 6,620 6,620 0.52 1.06 13.8 6,964 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.05 0.04 0.04 0.50 0.00 0.00 0.51 0.51 0.00 0.13 0.13 — 119 119 < 0.005 0.01 0.01 120 Vendor 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 0.00 Hauling 0.66 0.14 8.67 4.03 0.04 0.12 5.91 6.03 0.08 1.52 1.60 — 6,622 6,622 0.52 1.06 0.36 6,953 Average
Daily
— — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.03 0.00 0.00 0.03 0.03 0.00 0.01 0.01 — 7.56 7.56 < 0.005 < 0.005 0.01 7.67 Vendor 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 0.00 Hauling 0.04 0.01 0.54 0.25 < 0.005 0.01 0.37 0.38 0.01 0.09 0.10 — 417 417 0.03 0.07 0.37 438 Annual — — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.01 0.00 0.00 0.01 0.01 0.00 < 0.005 < 0.005 — 1.25 1.25 < 0.005 < 0.005 < 0.005 1.27 Vendor 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 0.00 Hauling 0.01 < 0.005 0.10 0.05 < 0.005 < 0.005 0.07 0.07 < 0.005 0.02 0.02 — 69.1 69.1 0.01 0.01 0.06 72.6

3.2. Demolition (2026) - Mitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Onsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.36 0.36 4.51 18.2 0.03 0.06 — 0.06 0.06 — 0.06 — 3,427 3,427 0.14 0.03 — 3,438 -------------------

East County Service Center - MIT Detailed Report, 7/8/2025 19 / 85
Demoliti — — — — — — 5.30 5.30 — 0.80 0.80 — — — — — — — on
Onsite
truck

0.02 0.01 0.22 0.16 < 0.005 < 0.005 0.68 0.68 < 0.005 0.07 0.07 — 34.8 34.8 0.01 0.01 0.02 36.7 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.36 0.36 4.51 18.2 0.03 0.06 — 0.06 0.06 — 0.06 — 3,427 3,427 0.14 0.03 — 3,438 Demoliti
on
— — — — — — 5.30 5.30 — 0.80 0.80 — — — — — — —
Onsite
truck

0.02 0.01 0.23 0.16 < 0.005 < 0.005 0.68 0.68 < 0.005 0.07 0.07 — 35.2 35.2 0.01 0.01 < 0.005 37.1 Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.02 0.02 0.28 1.15 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 216 216 0.01 < 0.005 — 217 Demoliti
on
— — — — — — 0.33 0.33 — 0.05 0.05 — — — — — — —
Onsite
truck
< 0.005 < 0.005 0.01 0.01 < 0.005 < 0.005 0.04 0.04 < 0.005 < 0.005 < 0.005 — 2.20 2.20 < 0.005 < 0.005 < 0.005 2.32 Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
< 0.005 < 0.005 0.05 0.21 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 35.7 35.7 < 0.005 < 0.005 — 35.9 Demoliti
on
— — — — — — 0.06 0.06 — 0.01 0.01 — — — — — — —
Onsite
truck
< 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 0.01 0.01 < 0.005 < 0.005 < 0.005 — 0.36 0.36 < 0.005 < 0.005 < 0.005 0.38 Offsite — — — — — — — — — — — — — — — — — —

East County Service Center - MIT Detailed Report, 7/8/2025 20 / 85
Daily, — — — — — — — — — — — — — — — — — —
Summer
(Max)
Worker 0.05 0.05 0.03 0.59 0.00 0.00 0.51 0.51 0.00 0.13 0.13 — 130 130 < 0.005 < 0.005 0.48 132 Vendor 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 0.00 Hauling 0.67 0.14 8.27 4.00 0.04 0.12 5.91 6.03 0.08 1.52 1.60 — 6,620 6,620 0.52 1.06 13.8 6,964 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.05 0.04 0.04 0.50 0.00 0.00 0.51 0.51 0.00 0.13 0.13 — 119 119 < 0.005 0.01 0.01 120 Vendor 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 0.00 Hauling 0.66 0.14 8.67 4.03 0.04 0.12 5.91 6.03 0.08 1.52 1.60 — 6,622 6,622 0.52 1.06 0.36 6,953 Average
Daily
— — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.03 0.00 0.00 0.03 0.03 0.00 0.01 0.01 — 7.56 7.56 < 0.005 < 0.005 0.01 7.67 Vendor 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 0.00 Hauling 0.04 0.01 0.54 0.25 < 0.005 0.01 0.37 0.38 0.01 0.09 0.10 — 417 417 0.03 0.07 0.37 438 Annual — — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.01 0.00 0.00 0.01 0.01 0.00 < 0.005 < 0.005 — 1.25 1.25 < 0.005 < 0.005 < 0.005 1.27 Vendor 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 0.00 Hauling 0.01 < 0.005 0.10 0.05 < 0.005 < 0.005 0.07 0.07 < 0.005 0.02 0.02 — 69.1 69.1 0.01 0.01 0.06 72.6

3.3. Site Preparation (2026) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Onsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
------------------- — — — — — — — — — — — — — — — — — —

East County Service Center - MIT Detailed Report, 7/8/2025 21 / 85
Daily, — — — — — — — — — — — — — — — — — —
Winter
(Max)
Off-Roa
d
Equipm
ent

3.74 3.14 29.2 28.8 0.05 1.24 — 1.24 1.14 — 1.14 — 5,298 5,298 0.21 0.04 — 5,316 Dust
From
Material
Movement
— — — — — — 5.11 5.11 — 2.63 2.63 — — — — — — —
Onsite
truck

0.02 0.01 0.27 0.19 < 0.005 < 0.005 0.80 0.80 < 0.005 0.08 0.08 — 41.0 41.0 0.01 0.01 < 0.005 43.3 Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.45 0.38 3.52 3.47 0.01 0.15 — 0.15 0.14 — 0.14 — 639 639 0.03 0.01 — 641 Dust
From
Material
Movement
— — — — — — 0.62 0.62 — 0.32 0.32 — — — — — — —
Onsite
truck
< 0.005 < 0.005 0.03 0.02 < 0.005 < 0.005 0.09 0.09 < 0.005 0.01 0.01 — 4.91 4.91 < 0.005 < 0.005 < 0.005 5.19 Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.08 0.07 0.64 0.63 < 0.005 0.03 — 0.03 0.03 — 0.03 — 106 106 < 0.005 < 0.005 — 106 Dust
From
Material
Movement
— — — — — — 0.11 0.11 — 0.06 0.06 — — — — — — —
Onsite
truck
< 0.005 < 0.005 0.01 < 0.005 < 0.005 < 0.005 0.02 0.02 < 0.005 < 0.005 < 0.005 — 0.81 0.81 < 0.005 < 0.005 < 0.005 0.86 Offsite — — — — — — — — — — — — — — — — — —

East County Service Center - MIT Detailed Report, 7/8/2025 22 / 85
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.06 0.05 0.05 0.58 0.00 0.00 0.60 0.60 0.00 0.15 0.15 — 138 138 < 0.005 0.01 0.01 140 Vendor 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 0.00 Hauling 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 0.00 Average
Daily
— — — — — — — — — — — — — — — — — —
Worker 0.01 0.01 0.01 0.07 0.00 0.00 0.07 0.07 0.00 0.02 0.02 — 16.9 16.9 < 0.005 < 0.005 0.03 17.1 Vendor 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 0.00 Hauling 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 0.00 Annual — — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.01 0.00 0.00 0.01 0.01 0.00 < 0.005 < 0.005 — 2.79 2.79 < 0.005 < 0.005 < 0.005 2.83 Vendor 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 0.00 Hauling 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 0.00

3.4. Site Preparation (2026) - Mitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Onsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
-------------------

East County Service Center - MIT Detailed Report, 7/8/2025 23 / 85
Off-Roa 0.50 0.50 2.59 28.3 0.05 0.10 — 0.10 0.10 — 0.10 — 5,298 5,298 0.21 0.04 — 5,316 d
Equipm
ent
Dust
From
Material
Movement
— — — — — — 5.11 5.11 — 2.63 2.63 — — — — — — —
Onsite
truck

0.02 0.01 0.27 0.19 < 0.005 < 0.005 0.80 0.80 < 0.005 0.08 0.08 — 41.0 41.0 0.01 0.01 < 0.005 43.3 Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.06 0.06 0.31 3.41 0.01 0.01 — 0.01 0.01 — 0.01 — 639 639 0.03 0.01 — 641 Dust
From
Material
Movement
— — — — — — 0.62 0.62 — 0.32 0.32 — — — — — — —
Onsite
truck
< 0.005 < 0.005 0.03 0.02 < 0.005 < 0.005 0.09 0.09 < 0.005 0.01 0.01 — 4.91 4.91 < 0.005 < 0.005 < 0.005 5.19 Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.01 0.01 0.06 0.62 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 106 106 < 0.005 < 0.005 — 106 Dust
From
Material
Movement
— — — — — — 0.11 0.11 — 0.06 0.06 — — — — — — —
Onsite
truck
< 0.005 < 0.005 0.01 < 0.005 < 0.005 < 0.005 0.02 0.02 < 0.005 < 0.005 < 0.005 — 0.81 0.81 < 0.005 < 0.005 < 0.005 0.86 Offsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —

East County Service Center - MIT Detailed Report, 7/8/2025 24 / 85
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.06 0.05 0.05 0.58 0.00 0.00 0.60 0.60 0.00 0.15 0.15 — 138 138 < 0.005 0.01 0.01 140 Vendor 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 0.00 Hauling 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 0.00 Average
Daily
— — — — — — — — — — — — — — — — — —
Worker 0.01 0.01 0.01 0.07 0.00 0.00 0.07 0.07 0.00 0.02 0.02 — 16.9 16.9 < 0.005 < 0.005 0.03 17.1 Vendor 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 0.00 Hauling 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 0.00 Annual — — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.01 0.00 0.00 0.01 0.01 0.00 < 0.005 < 0.005 — 2.79 2.79 < 0.005 < 0.005 < 0.005 2.83 Vendor 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 0.00 Hauling 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 0.00

3.5. Grading (2026) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Onsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

1.96 1.65 15.0 17.4 0.03 0.65 — 0.65 0.59 — 0.59 — 2,960 2,960 0.12 0.02 — 2,970 -------------------

East County Service Center - MIT Detailed Report, 7/8/2025 25 / 85
Dust — — — — — — 1.84 1.84 — 0.89 0.89 — — — — — — —
From
Material
Movement
Onsite
truck

0.02 0.01 0.23 0.16 < 0.005 < 0.005 0.68 0.68 < 0.005 0.07 0.07 — 35.2 35.2 0.01 0.01 < 0.005 37.1 Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.06 0.05 0.47 0.55 < 0.005 0.02 — 0.02 0.02 — 0.02 — 92.7 92.7 < 0.005 < 0.005 — 93.0 Dust
From
Material
Movement
— — — — — — 0.06 0.06 — 0.03 0.03 — — — — — — —
Onsite
truck
< 0.005 < 0.005 0.01 0.01 < 0.005 < 0.005 0.02 0.02 < 0.005 < 0.005 < 0.005 — 1.09 1.09 < 0.005 < 0.005 < 0.005 1.16 Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.01 0.01 0.09 0.10 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 15.3 15.3 < 0.005 < 0.005 — 15.4 Dust
From
Material
Movement
— — — — — — 0.01 0.01 — 0.01 0.01 — — — — — — —
Onsite
truck
< 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 — 0.18 0.18 < 0.005 < 0.005 < 0.005 0.19 Offsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.05 0.04 0.04 0.50 0.00 0.00 0.51 0.51 0.00 0.13 0.13 — 119 119 < 0.005 0.01 0.01 120 Page 247 of 1860 East County Service Center - MIT Detailed Report, 7/8/2025 26 / 85
Vendor 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 0.00 Hauling 0.12 0.02 1.53 0.71 0.01 0.02 1.04 1.07 0.01 0.27 0.28 — 1,170 1,170 0.09 0.19 0.06 1,228 Average
Daily
— — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.02 0.00 0.00 0.02 0.02 0.00 < 0.005 < 0.005 — 3.75 3.75 < 0.005 < 0.005 0.01 3.81 Vendor 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 0.00 Hauling < 0.005 < 0.005 0.05 0.02 < 0.005 < 0.005 0.03 0.03 < 0.005 0.01 0.01 — 36.6 36.6 < 0.005 0.01 0.03 38.5 Annual — — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 < 0.005 0.00 0.00 < 0.005 < 0.005 0.00 < 0.005 < 0.005 — 0.62 0.62 < 0.005 < 0.005 < 0.005 0.63 Vendor 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 0.00 Hauling < 0.005 < 0.005 0.01 < 0.005 < 0.005 < 0.005 0.01 0.01 < 0.005 < 0.005 < 0.005 — 6.06 6.06 < 0.005 < 0.005 0.01 6.37

3.6. Grading (2026) - Mitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Onsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.29 0.29 2.04 17.8 0.03 0.06 — 0.06 0.06 — 0.06 — 2,960 2,960 0.12 0.02 — 2,970 Dust
From
Material
Movement
— — — — — — 1.84 1.84 — 0.89 0.89 — — — — — — —
Onsite
truck

0.02 0.01 0.23 0.16 < 0.005 < 0.005 0.68 0.68 < 0.005 0.07 0.07 — 35.2 35.2 0.01 0.01 < 0.005 37.1 -------------------

East County Service Center - MIT Detailed Report, 7/8/2025 27 / 85
Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.01 0.01 0.06 0.56 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 92.7 92.7 < 0.005 < 0.005 — 93.0 Dust
From
Material
Movement
— — — — — — 0.06 0.06 — 0.03 0.03 — — — — — — —
Onsite
truck
< 0.005 < 0.005 0.01 0.01 < 0.005 < 0.005 0.02 0.02 < 0.005 < 0.005 < 0.005 — 1.09 1.09 < 0.005 < 0.005 < 0.005 1.16 Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
< 0.005 < 0.005 0.01 0.10 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 15.3 15.3 < 0.005 < 0.005 — 15.4 Dust
From
Material
Movement
— — — — — — 0.01 0.01 — 0.01 0.01 — — — — — — —
Onsite
truck
< 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 — 0.18 0.18 < 0.005 < 0.005 < 0.005 0.19 Offsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.05 0.04 0.04 0.50 0.00 0.00 0.51 0.51 0.00 0.13 0.13 — 119 119 < 0.005 0.01 0.01 120 Vendor 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 0.00 Hauling 0.12 0.02 1.53 0.71 0.01 0.02 1.04 1.07 0.01 0.27 0.28 — 1,170 1,170 0.09 0.19 0.06 1,228 Average
Daily
— — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.02 0.00 0.00 0.02 0.02 0.00 < 0.005 < 0.005 — 3.75 3.75 < 0.005 < 0.005 0.01 3.81 Page 249 of 1860 East County Service Center - MIT Detailed Report, 7/8/2025 28 / 85
Vendor 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 0.00 Hauling < 0.005 < 0.005 0.05 0.02 < 0.005 < 0.005 0.03 0.03 < 0.005 0.01 0.01 — 36.6 36.6 < 0.005 0.01 0.03 38.5 Annual — — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 < 0.005 0.00 0.00 < 0.005 < 0.005 0.00 < 0.005 < 0.005 — 0.62 0.62 < 0.005 < 0.005 < 0.005 0.63 Vendor 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 0.00 Hauling < 0.005 < 0.005 0.01 < 0.005 < 0.005 < 0.005 0.01 0.01 < 0.005 < 0.005 < 0.005 — 6.06 6.06 < 0.005 < 0.005 0.01 6.37

3.7. Grading (2027) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Onsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

1.89 1.59 14.2 17.3 0.03 0.60 — 0.60 0.55 — 0.55 — 2,960 2,960 0.12 0.02 — 2,970 Dust
From
Material
Movement
— — — — — — 1.84 1.84 — 0.89 0.89 — — — — — — —
Onsite
truck

0.02 0.01 0.23 0.16 < 0.005 < 0.005 0.68 0.68 < 0.005 0.07 0.07 — 34.6 34.6 0.01 0.01 < 0.005 36.5 Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.17 0.15 1.31 1.59 < 0.005 0.05 — 0.05 0.05 — 0.05 — 272 272 0.01 < 0.005 — 273 -------------------

East County Service Center - MIT Detailed Report, 7/8/2025 29 / 85
Dust — — — — — — 0.17 0.17 — 0.08 0.08 — — — — — — —
From
Material
Movement
Onsite
truck
< 0.005 < 0.005 0.02 0.01 < 0.005 < 0.005 0.06 0.06 < 0.005 0.01 0.01 — 3.16 3.16 < 0.005 < 0.005 < 0.005 3.34 Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.03 0.03 0.24 0.29 < 0.005 0.01 — 0.01 0.01 — 0.01 — 45.1 45.1 < 0.005 < 0.005 — 45.2 Dust
From
Material
Movement
— — — — — — 0.03 0.03 — 0.01 0.01 — — — — — — —
Onsite
truck
< 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 0.01 0.01 < 0.005 < 0.005 < 0.005 — 0.52 0.52 < 0.005 < 0.005 < 0.005 0.55 Offsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.05 0.04 0.04 0.47 0.00 0.00 0.51 0.51 0.00 0.13 0.13 — 116 116 < 0.005 0.01 0.01 118 Vendor 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 0.00 Hauling 0.11 0.02 1.48 0.70 0.01 0.01 1.04 1.06 0.01 0.27 0.28 — 1,144 1,144 0.08 0.18 0.06 1,200 Average
Daily
— — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.04 0.00 0.00 0.05 0.05 0.00 0.01 0.01 — 10.8 10.8 < 0.005 < 0.005 0.02 11.0 Vendor 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 0.00 Hauling 0.01 < 0.005 0.13 0.06 < 0.005 < 0.005 0.09 0.10 < 0.005 0.02 0.03 — 105 105 0.01 0.02 0.09 110 Annual — — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.01 0.00 0.00 0.01 0.01 0.00 < 0.005 < 0.005 — 1.79 1.79 < 0.005 < 0.005 < 0.005 1.82

East County Service Center - MIT Detailed Report, 7/8/2025 30 / 85
Vendor 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 0.00 Hauling < 0.005 < 0.005 0.02 0.01 < 0.005 < 0.005 0.02 0.02 < 0.005 < 0.005 < 0.005 — 17.4 17.4 < 0.005 < 0.005 0.01 18.3

3.8. Grading (2027) - Mitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Onsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.29 0.29 2.04 17.8 0.03 0.06 — 0.06 0.06 — 0.06 — 2,960 2,960 0.12 0.02 — 2,970 Dust
From
Material
Movement
— — — — — — 1.84 1.84 — 0.89 0.89 — — — — — — —
Onsite
truck

0.02 0.01 0.23 0.16 < 0.005 < 0.005 0.68 0.68 < 0.005 0.07 0.07 — 34.6 34.6 0.01 0.01 < 0.005 36.5 Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.03 0.03 0.19 1.63 < 0.005 0.01 — 0.01 0.01 — 0.01 — 272 272 0.01 < 0.005 — 273 Dust
From
Material
Movement
— — — — — — 0.17 0.17 — 0.08 0.08 — — — — — — —
Onsite
truck
< 0.005 < 0.005 0.02 0.01 < 0.005 < 0.005 0.06 0.06 < 0.005 0.01 0.01 — 3.16 3.16 < 0.005 < 0.005 < 0.005 3.34 -------------------

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Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
< 0.005 < 0.005 0.03 0.30 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 45.1 45.1 < 0.005 < 0.005 — 45.2 Dust
From
Material
Movement
— — — — — — 0.03 0.03 — 0.01 0.01 — — — — — — —
Onsite
truck
< 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 0.01 0.01 < 0.005 < 0.005 < 0.005 — 0.52 0.52 < 0.005 < 0.005 < 0.005 0.55 Offsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.05 0.04 0.04 0.47 0.00 0.00 0.51 0.51 0.00 0.13 0.13 — 116 116 < 0.005 0.01 0.01 118 Vendor 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 0.00 Hauling 0.11 0.02 1.48 0.70 0.01 0.01 1.04 1.06 0.01 0.27 0.28 — 1,144 1,144 0.08 0.18 0.06 1,200 Average
Daily
— — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.04 0.00 0.00 0.05 0.05 0.00 0.01 0.01 — 10.8 10.8 < 0.005 < 0.005 0.02 11.0 Vendor 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 0.00 Hauling 0.01 < 0.005 0.13 0.06 < 0.005 < 0.005 0.09 0.10 < 0.005 0.02 0.03 — 105 105 0.01 0.02 0.09 110 Annual — — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.01 0.00 0.00 0.01 0.01 0.00 < 0.005 < 0.005 — 1.79 1.79 < 0.005 < 0.005 < 0.005 1.82 Vendor 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 0.00 Hauling < 0.005 < 0.005 0.02 0.01 < 0.005 < 0.005 0.02 0.02 < 0.005 < 0.005 < 0.005 — 17.4 17.4 < 0.005 < 0.005 0.01 18.3

3.9. Building Construction (2027) - Unmitigated

East County Service Center - MIT Detailed Report, 7/8/2025 32 / 85
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Onsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

1.23 1.03 9.39 12.9 0.02 0.34 — 0.34 0.31 — 0.31 — 2,397 2,397 0.10 0.02 — 2,405 Onsite
truck

0.08 0.04 0.85 0.61 < 0.005 < 0.005 2.64 2.64 < 0.005 0.26 0.26 — 132 132 0.04 0.02 0.08 140 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

1.23 1.03 9.39 12.9 0.02 0.34 — 0.34 0.31 — 0.31 — 2,397 2,397 0.10 0.02 — 2,405 Onsite
truck

0.08 0.03 0.89 0.63 < 0.005 < 0.005 2.64 2.64 < 0.005 0.26 0.26 — 134 134 0.04 0.02 < 0.005 141 Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.58 0.49 4.45 6.13 0.01 0.16 — 0.16 0.15 — 0.15 — 1,136 1,136 0.05 0.01 — 1,140 Onsite
truck

0.04 0.02 0.41 0.29 < 0.005 < 0.005 1.18 1.18 < 0.005 0.12 0.12 — 63.0 63.0 0.02 0.01 0.02 66.6 Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.11 0.09 0.81 1.12 < 0.005 0.03 — 0.03 0.03 — 0.03 — 188 188 0.01 < 0.005 — 189 Onsite
truck

0.01 < 0.005 0.08 0.05 < 0.005 < 0.005 0.22 0.22 < 0.005 0.02 0.02 — 10.4 10.4 < 0.005 < 0.005 < 0.005 11.0 -------------------

East County Service Center - MIT Detailed Report, 7/8/2025 33 / 85
Offsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.13 0.12 0.08 1.41 0.00 0.00 1.31 1.31 0.00 0.32 0.32 — 326 326 0.01 0.01 1.11 331 Vendor 0.05 0.02 0.64 0.31 < 0.005 0.01 0.50 0.51 0.01 0.13 0.14 — 511 511 0.03 0.08 1.11 536 Hauling 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 0.00 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.12 0.11 0.10 1.19 0.00 0.00 1.31 1.31 0.00 0.32 0.32 — 298 298 0.01 0.01 0.03 302 Vendor 0.04 0.02 0.67 0.32 < 0.005 0.01 0.50 0.51 0.01 0.13 0.14 — 512 512 0.03 0.08 0.03 535 Hauling 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 0.00 Average
Daily
— — — — — — — — — — — — — — — — — —
Worker 0.06 0.05 0.04 0.55 0.00 0.00 0.61 0.61 0.00 0.15 0.15 — 143 143 < 0.005 0.01 0.23 145 Vendor 0.02 0.01 0.31 0.15 < 0.005 < 0.005 0.24 0.24 < 0.005 0.06 0.06 — 242 242 0.01 0.04 0.23 254 Hauling 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 0.00 Annual — — — — — — — — — — — — — — — — — —
Worker 0.01 0.01 0.01 0.10 0.00 0.00 0.11 0.11 0.00 0.03 0.03 — 23.7 23.7 < 0.005 < 0.005 0.04 24.0 Vendor < 0.005 < 0.005 0.06 0.03 < 0.005 < 0.005 0.04 0.04 < 0.005 0.01 0.01 — 40.1 40.1 < 0.005 0.01 0.04 42.0 Hauling 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 0.00

3.10. Building Construction (2027) - Mitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Onsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
------------------- — — — — — — — — — — — — — — — — — —

East County Service Center - MIT Detailed Report, 7/8/2025 34 / 85
Off-Roa 0.35 0.33 2.82 14.8 0.02 0.07 — 0.07 0.07 — 0.07 — 2,397 2,397 0.10 0.02 — 2,405 d
Onsite
truck

0.08 0.04 0.85 0.61 < 0.005 < 0.005 2.64 2.64 < 0.005 0.26 0.26 — 132 132 0.04 0.02 0.08 140 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.35 0.33 2.82 14.8 0.02 0.07 — 0.07 0.07 — 0.07 — 2,397 2,397 0.10 0.02 — 2,405 Onsite
truck

0.08 0.03 0.89 0.63 < 0.005 < 0.005 2.64 2.64 < 0.005 0.26 0.26 — 134 134 0.04 0.02 < 0.005 141 Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.17 0.16 1.34 7.03 0.01 0.04 — 0.04 0.03 — 0.03 — 1,136 1,136 0.05 0.01 — 1,140 Onsite
truck

0.04 0.02 0.41 0.29 < 0.005 < 0.005 1.18 1.18 < 0.005 0.12 0.12 — 63.0 63.0 0.02 0.01 0.02 66.6 Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.03 0.03 0.24 1.28 < 0.005 0.01 — 0.01 0.01 — 0.01 — 188 188 0.01 < 0.005 — 189 Onsite
truck

0.01 < 0.005 0.08 0.05 < 0.005 < 0.005 0.22 0.22 < 0.005 0.02 0.02 — 10.4 10.4 < 0.005 < 0.005 < 0.005 11.0 Offsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.13 0.12 0.08 1.41 0.00 0.00 1.31 1.31 0.00 0.32 0.32 — 326 326 0.01 0.01 1.11 331 Vendor 0.05 0.02 0.64 0.31 < 0.005 0.01 0.50 0.51 0.01 0.13 0.14 — 511 511 0.03 0.08 1.11 536 Hauling 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 0.00

East County Service Center - MIT Detailed Report, 7/8/2025 35 / 85
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.12 0.11 0.10 1.19 0.00 0.00 1.31 1.31 0.00 0.32 0.32 — 298 298 0.01 0.01 0.03 302 Vendor 0.04 0.02 0.67 0.32 < 0.005 0.01 0.50 0.51 0.01 0.13 0.14 — 512 512 0.03 0.08 0.03 535 Hauling 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 0.00 Average
Daily
— — — — — — — — — — — — — — — — — —
Worker 0.06 0.05 0.04 0.55 0.00 0.00 0.61 0.61 0.00 0.15 0.15 — 143 143 < 0.005 0.01 0.23 145 Vendor 0.02 0.01 0.31 0.15 < 0.005 < 0.005 0.24 0.24 < 0.005 0.06 0.06 — 242 242 0.01 0.04 0.23 254 Hauling 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 0.00 Annual — — — — — — — — — — — — — — — — — —
Worker 0.01 0.01 0.01 0.10 0.00 0.00 0.11 0.11 0.00 0.03 0.03 — 23.7 23.7 < 0.005 < 0.005 0.04 24.0 Vendor < 0.005 < 0.005 0.06 0.03 < 0.005 < 0.005 0.04 0.04 < 0.005 0.01 0.01 — 40.1 40.1 < 0.005 0.01 0.04 42.0 Hauling 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 0.00

3.11. Paving (2027) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Onsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.88 0.74 6.94 9.95 0.01 0.30 — 0.30 0.27 — 0.27 — 1,511 1,511 0.06 0.01 — 1,516 Paving 0.21 0.21 — — — — — — — — — — — — — — — —
-------------------

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Onsite 0.02 0.01 0.23 0.16 < 0.005 < 0.005 0.68 0.68 < 0.005 0.07 0.07 — 34.6 34.6 0.01 0.01 < 0.005 36.5 truck
Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.11 0.09 0.86 1.23 < 0.005 0.04 — 0.04 0.03 — 0.03 — 186 186 0.01 < 0.005 — 187 Paving 0.03 0.03 — — — — — — — — — — — — — — — —
Onsite
truck
< 0.005 < 0.005 0.03 0.02 < 0.005 < 0.005 0.08 0.08 < 0.005 0.01 0.01 — 4.23 4.23 < 0.005 < 0.005 < 0.005 4.47 Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.02 0.02 0.16 0.22 < 0.005 0.01 — 0.01 0.01 — 0.01 — 30.8 30.8 < 0.005 < 0.005 — 31.0 Paving < 0.005 < 0.005 — — — — — — — — — — — — — — — —
Onsite
truck
< 0.005 < 0.005 0.01 < 0.005 < 0.005 < 0.005 0.01 0.01 < 0.005 < 0.005 < 0.005 — 0.70 0.70 < 0.005 < 0.005 < 0.005 0.74 Offsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.05 0.04 0.04 0.47 0.00 0.00 0.51 0.51 0.00 0.13 0.13 — 116 116 < 0.005 0.01 0.01 118 Vendor 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 0.00 Hauling 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 0.00 Average
Daily
— — — — — — — — — — — — — — — — — —
Worker 0.01 0.01 < 0.005 0.06 0.00 0.00 0.06 0.06 0.00 0.02 0.02 — 14.5 14.5 < 0.005 < 0.005 0.02 14.7 Vendor 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 0.00 Hauling 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 0.00

East County Service Center - MIT Detailed Report, 7/8/2025 37 / 85
Annual — — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.01 0.00 0.00 0.01 0.01 0.00 < 0.005 < 0.005 — 2.40 2.40 < 0.005 < 0.005 < 0.005 2.44 Vendor 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 0.00 Hauling 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 0.00

3.12. Paving (2027) - Mitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Onsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.16 0.16 1.93 10.6 0.01 0.03 — 0.03 0.03 — 0.03 — 1,511 1,511 0.06 0.01 — 1,516 Paving 0.21 0.21 — — — — — — — — — — — — — — — —
Onsite
truck

0.02 0.01 0.23 0.16 < 0.005 < 0.005 0.68 0.68 < 0.005 0.07 0.07 — 34.6 34.6 0.01 0.01 < 0.005 36.5 Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.02 0.02 0.24 1.31 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 186 186 0.01 < 0.005 — 187 Paving 0.03 0.03 — — — — — — — — — — — — — — — —
Onsite
truck
< 0.005 < 0.005 0.03 0.02 < 0.005 < 0.005 0.08 0.08 < 0.005 0.01 0.01 — 4.23 4.23 < 0.005 < 0.005 < 0.005 4.47 Annual — — — — — — — — — — — — — — — — — —
-------------------

East County Service Center - MIT Detailed Report, 7/8/2025 38 / 85
Off-Roa < 0.005 < 0.005 0.04 0.24 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 30.8 30.8 < 0.005 < 0.005 — 31.0 d
Paving < 0.005 < 0.005 — — — — — — — — — — — — — — — —
Onsite
truck
< 0.005 < 0.005 0.01 < 0.005 < 0.005 < 0.005 0.01 0.01 < 0.005 < 0.005 < 0.005 — 0.70 0.70 < 0.005 < 0.005 < 0.005 0.74 Offsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.05 0.04 0.04 0.47 0.00 0.00 0.51 0.51 0.00 0.13 0.13 — 116 116 < 0.005 0.01 0.01 118 Vendor 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 0.00 Hauling 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 0.00 Average
Daily
— — — — — — — — — — — — — — — — — —
Worker 0.01 0.01 < 0.005 0.06 0.00 0.00 0.06 0.06 0.00 0.02 0.02 — 14.5 14.5 < 0.005 < 0.005 0.02 14.7 Vendor 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 0.00 Hauling 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 0.00 Annual — — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.01 0.00 0.00 0.01 0.01 0.00 < 0.005 < 0.005 — 2.40 2.40 < 0.005 < 0.005 < 0.005 2.44 Vendor 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 0.00 Hauling 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 0.00

3.13. Architectural Coating (2027) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e -------------------
Onsite — — — — — — — — — — — — — — — — — —

East County Service Center - MIT Detailed Report, 7/8/2025 39 / 85
Daily, — — — — — — — — — — — — — — — — — —
Summer
(Max)
Off-Roa
d
Equipm
ent

0.14 0.11 0.83 1.13 < 0.005 0.02 — 0.02 0.02 — 0.02 — 134 134 0.01 < 0.005 — 134 Architect
ural
Coating
s

15.1 15.1 — — — — — — — — — — — — — — — —
Onsite
truck

0.01 < 0.005 0.11 0.08 < 0.005 < 0.005 0.35 0.35 < 0.005 0.03 0.04 — 17.5 17.5 0.01 < 0.005 0.01 18.5 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.14 0.11 0.83 1.13 < 0.005 0.02 — 0.02 0.02 — 0.02 — 134 134 0.01 < 0.005 — 134 Architect
ural
Coating
s

15.1 15.1 — — — — — — — — — — — — — — — —
Onsite
truck

0.01 < 0.005 0.12 0.08 < 0.005 < 0.005 0.35 0.35 < 0.005 0.03 0.04 — 17.8 17.8 0.01 < 0.005 < 0.005 18.7 Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.03 0.03 0.20 0.27 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 32.2 32.2 < 0.005 < 0.005 — 32.3 Architect
ural
Coating
s

3.64 3.64 — — — — — — — — — — — — — — — —
Onsite
truck
< 0.005 < 0.005 0.03 0.02 < 0.005 < 0.005 0.08 0.08 < 0.005 0.01 0.01 — 4.25 4.25 < 0.005 < 0.005 < 0.005 4.49

East County Service Center - MIT Detailed Report, 7/8/2025 40 / 85
Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.01 < 0.005 0.04 0.05 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 5.33 5.33 < 0.005 < 0.005 — 5.35 Architect
ural
Coating
s

0.66 0.66 — — — — — — — — — — — — — — — —
Onsite
truck
< 0.005 < 0.005 0.01 < 0.005 < 0.005 < 0.005 0.01 0.01 < 0.005 < 0.005 < 0.005 — 0.70 0.70 < 0.005 < 0.005 < 0.005 0.74 Offsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.03 0.02 0.02 0.28 0.00 0.00 0.26 0.26 0.00 0.06 0.06 — 65.2 65.2 < 0.005 < 0.005 0.22 66.2 Vendor 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 0.00 Hauling 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 0.00 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.02 0.02 0.02 0.24 0.00 0.00 0.26 0.26 0.00 0.06 0.06 — 59.6 59.6 < 0.005 < 0.005 0.01 60.5 Vendor 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 0.00 Hauling 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 0.00 Average
Daily
— — — — — — — — — — — — — — — — — —
Worker 0.01 0.01 < 0.005 0.06 0.00 0.00 0.06 0.06 0.00 0.02 0.02 — 14.5 14.5 < 0.005 < 0.005 0.02 14.7 Vendor 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 0.00 Hauling 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 0.00 Annual — — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.01 0.00 0.00 0.01 0.01 0.00 < 0.005 < 0.005 — 2.41 2.41 < 0.005 < 0.005 < 0.005 2.44 Vendor 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 0.00 Hauling 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 0.00 Page 262 of 1860 East County Service Center - MIT Detailed Report, 7/8/2025 41 / 85

3.14. Architectural Coating (2027) - Mitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Onsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.02 0.02 0.65 0.96 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 134 134 0.01 < 0.005 — 134 Architect
ural
Coating
s

15.1 15.1 — — — — — — — — — — — — — — — —
Onsite
truck

0.01 < 0.005 0.11 0.08 < 0.005 < 0.005 0.35 0.35 < 0.005 0.03 0.04 — 17.5 17.5 0.01 < 0.005 0.01 18.5 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.02 0.02 0.65 0.96 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 134 134 0.01 < 0.005 — 134 Architect
ural
Coating
s

15.1 15.1 — — — — — — — — — — — — — — — —
Onsite
truck

0.01 < 0.005 0.12 0.08 < 0.005 < 0.005 0.35 0.35 < 0.005 0.03 0.04 — 17.8 17.8 0.01 < 0.005 < 0.005 18.7 Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent

0.01 0.01 0.16 0.23 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 32.2 32.2 < 0.005 < 0.005 — 32.3 -------------------

East County Service Center - MIT Detailed Report, 7/8/2025 42 / 85
Architect
Coatings

3.64 3.64 — — — — — — — — — — — — — — — —
Onsite
truck
< 0.005 < 0.005 0.03 0.02 < 0.005 < 0.005 0.08 0.08 < 0.005 0.01 0.01 — 4.25 4.25 < 0.005 < 0.005 < 0.005 4.49 Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
< 0.005 < 0.005 0.03 0.04 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 5.33 5.33 < 0.005 < 0.005 — 5.35 Architect
ural
Coating
s

0.66 0.66 — — — — — — — — — — — — — — — —
Onsite
truck
< 0.005 < 0.005 0.01 < 0.005 < 0.005 < 0.005 0.01 0.01 < 0.005 < 0.005 < 0.005 — 0.70 0.70 < 0.005 < 0.005 < 0.005 0.74 Offsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.03 0.02 0.02 0.28 0.00 0.00 0.26 0.26 0.00 0.06 0.06 — 65.2 65.2 < 0.005 < 0.005 0.22 66.2 Vendor 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 0.00 Hauling 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 0.00 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.02 0.02 0.02 0.24 0.00 0.00 0.26 0.26 0.00 0.06 0.06 — 59.6 59.6 < 0.005 < 0.005 0.01 60.5 Vendor 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 0.00 Hauling 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 0.00 Average
Daily
— — — — — — — — — — — — — — — — — —
Worker 0.01 0.01 < 0.005 0.06 0.00 0.00 0.06 0.06 0.00 0.02 0.02 — 14.5 14.5 < 0.005 < 0.005 0.02 14.7 Vendor 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 0.00 Hauling 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 0.00 Annual — — — — — — — — — — — — — — — — — — Page 264 of 1860 East County Service Center - MIT Detailed Report, 7/8/2025 43 / 85
Worker < 0.005 < 0.005 < 0.005 0.01 0.00 0.00 0.01 0.01 0.00 < 0.005 < 0.005 — 2.41 2.41 < 0.005 < 0.005 < 0.005 2.44 Vendor 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 0.00 Hauling 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 0.00

4. Operations Emissions Details

4.1. Mobile Emissions by Land Use

4.1.1. Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual) Land
Use
TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Govern
ment
(Civic
Center)

10.4 9.86 5.20 56.5 0.13 0.08 12.1 12.2 0.08 3.07 3.15 — 13,098 13,098 0.65 0.57 33.9 13,319 Parking
Lot

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 0.00 Other
Non-Asphalt
Surfaces

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 0.00 Total 10.4 9.86 5.20 56.5 0.13 0.08 12.1 12.2 0.08 3.07 3.15 — 13,098 13,098 0.65 0.57 33.9 13,319 Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Govern
ment
(Civic
Center)

9.86 9.25 6.13 56.2 0.12 0.08 12.1 12.2 0.08 3.07 3.15 — 12,228 12,228 0.77 0.64 0.88 12,438 Parking
Lot

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 0.00