Brentwood City Council
February 10, 2026

JANUARY 27, 2026, 7:00 PM

CITY COUNCIL/SUCCESSOR AGENCY AGENDA
CITY COUNCIL CHAMBERS, 150 CITY PARK WAY
*IMPORTANT NOTICE ABOUT PUBLIC COMMENTS AND MEETING PARTICIPATION* City Council Members will be participating from the Council Chamber. Members of the public are invited to attend and participate at: the Council Chambers, 150 City Park Way, Brentwood CA As a courtesy and technology permitting, members of the public may provide remote public comment during public hearings and on business items via the City’s Zoom Platform. However, the City cannot guarantee that the public’s access to teleconferencing technology will be uninterrupted, and technical difficulties may occur from time to time. In those instances, so long as the public may still attend the meeting in person, the meeting will continue. In addition, the Zoom participation option is provided to the public as a courtesy in order to facilitate participation. If Zoom participation is not enabled, the meeting will continue with public attendance in person only. Members of the public desiring to provide comments as a part of the meeting are encouraged to either submit written comments by 3:00 p.m. prior to the meeting or to attend the meeting in person.

HOW TO PARTICIPATE
The public is invited to participate in the City Council meeting using any of the following methods:

1. IN PERSON:
a. Members of the public can provide in-person comments in the Council Chambers.

Members of the public are encouraged, but not required, to fill out a speaker card. The Council Chambers will have seating available for members of the public to attend in person up to full seating capacity.

2. REMOTE:
a. Zoom: www.brentwoodca.gov/vcc or Zoom Webinar ID: 760 1397 0037 b. Zoom Phone Numbers. Dial Toll Free: (833) 548-0276 or (833) 548-0282 or (877) 853-5247.
c. During the meeting, each period for public comment will be announced, and participants may use the “Raise Hand” feature on Zoom to request to speak. (If you need instructions on how to use this feature, please contact the City Clerk by noon of the meeting date at [email protected] or 925.516.5182.)

3. E-MAIL:
a. Public comments can also be submitted via e-mail to [email protected]. Any public comments received up until 3:00 p.m. of the meeting date will be:

1. distributed to the Council via email before the meeting,

2. posted online for public inspection at www.brentwoodca.gov/meetings and

3. later summarized in the meeting minutes.
b. As e-mails containing public meeting comments are part of the official record, note that personal contact information may be published if it is included with your e-mail.

4. TO WATCH OR LISTEN ONLY:
a. The public may view the meeting via one-way video feed by selecting the video option at the City Council Agendas’ link on the City webpage at www.brentwoodca.gov or via the City’s YouTube Channel: https://www.youtube.com/c/cityofbrentwoodca

CITY COUNCIL/SUCCESSOR AGENCY AGENDA

Zoom Webinar ID: 760 1397 0037

February 10, 2026, 7:00 p.m.

City Council Chambers
150 City Park Way
Brentwood, CA 94513
City Council Zoom Link
A. CALL TO ORDER & ROLL CALL
B. PLEDGE OF ALLEGIANCE
C. PRESENTATIONS
C.1 DoorDash Delivery Robots
D. PUBLIC COMMENTS
Pursuant to Council/Administrative Policy, Meeting Rules and Procedures section 5.2 (Decorum Generally – Public), comments by members of the public are generally limited to five minutes, or less time if a large number of speakers is anticipated, or if approved by the Mayor. Speakers desiring answers to questions should direct them to the Council/Successor Agency and, if relevant, they may direct them to the appropriate staff member. Speakers can also follow up directly with staff during regular City business hours.

Please file a speaker’s card with the City Clerk on the form provided on the counter at the back of the Chambers.

During this portion of the meeting those present in the Council Chambers are permitted to speak on items that are listed under Presentations; Informational Reports; Consent Calendar; Requests for Future Agenda Items- New Items; or items not on the agenda during this portion of the meeting. Public comments for scheduled agenda items should wait until that time.

In order to ensure that all speakers feel welcome to share their views, members of the audience are kindly requested to refrain from applauding or speaking to the Council from the audience without being called upon first.

E. INFORMATIONAL REPORTS FROM COUNCIL MEMBERS, COMMITTEES, LIAISONS, AND STAFF This portion of the agenda is to provide an opportunity for Council Members to report on attendance at events, subcommittee meetings, and entities on which the Council Member has been appointed as a liaison and for staff to provide brief updates and/or information to the City Council.

F. CONSENT CALENDAR
All matters listed on the consent calendar are considered routine in nature and will be enacted by one motion. If discussion is required, that particular item will be removed from the consent calendar and will be considered separately.

F.1 Meeting Minutes of the City Council
Special City Council Meeting Minutes of January 27, 2026 City Council / Successor Agency Meeting Minutes of January 27, 2026 G. PUBLIC HEARINGS
Persons addressing the City Council using Zoom are asked to raise their hands using the Zoom feature. Those attending in person and wishing to address the Council may do so from the podium. The Council may adopt reasonable regulations at the onset of the public hearing to facilitate public testimony. These regulations may include time limits. In the absence of such regulations, the public hearing shall follow the protocol for Public Comments.

H. BUSINESS ITEMS
Persons addressing the City Council using Zoom are asked to raise their hands using the Zoom feature. Those attending in person and wishing to address the Council may do so from the podium. The Council may adopt reasonable regulations at the onset of each business item to facilitate public testimony. These regulations may include time limits. In the absence of such regulations, the item shall follow the protocol for Public Comments. Public comment on each of the following items is limited to what is described in the specific agenda item.

H.1 Award of contract to Mountain Cascade Inc. for the Municipal Services Center Pavement Rehab
Title/Recommendation
Adopt a Resolution approving the contract documents, awarding the bid, and authorizing the City Manager or designee to execute a contract and necessary documents for the Municipal Services Center Pavement Rehab (“Project”) with Mountain Cascade Inc. as the lowest responsible and responsive bidder in the amount of $341,860.00, plus funding authorization for a 15% contingency of $51,279.00, for a total funding authorization notto-exceed amount of $393,139.00.

Per 14 CCR § 15062, a CEQA Notice of Exemption was filed with the Contra Costa County Clerk Recorder on January 15, 2026.

H.2 Informational Report on the East County Service Center Initial Study/Mitigated Negative Declaration and City Processes
Title/Recommendation
Receive informational report on the release of the Initial Study/Mitigated Negative Declaration (IS/MND) for the East County Service Center project and City processes related to the project.

I. REQUEST FOR FUTURE AGENDA ITEMS - NEW REQUEST(S)
Council Members wishing to have an agenda item placed on a future agenda shall make a request under this section of the agenda. These items will be included on the agenda for the next Council meeting
J. REQUESTED FUTURE AGENDA ITEM(S)
J.1 Consider a request from Mayor Meyer and Council Member Mendoza regarding content standards for the City’s website and the Better in Brentwood website pages, and the use of press releases
Title/Recommendation
That the City Council consider and discuss Mayor Meyer and Council Member Mendoza’s request that the City’s website and associated social media pages be limited to City business and official City activity; that business and retail promotions be posted only on the Better in Brentwood website and associated social media pages; and that a standard be set related to information released through press releases.

K. ADJOURNMENT
Any disclosable public records related to an agenda item for the open session of this meeting distributed to all or a majority of the City Council less than 72 hours before this meeting are available for inspection at City Hall, located at 150 City Park Way, during normal business hours.

These writings will also be available for review at the City Council meeting in the public access binder in the entrance of the City Council Chambers.

Public comments received after 3:00 p.m. of the meeting date, but prior to the start of the meeting, will be emailed to the City Council, posted online at www.brentwoodca.gov/councilmeetingonline within one day following the meeting, and will be summarized in the meeting minutes.

The Closed Captioning provided via Zoom is auto generated. It is not the official record and is

provided as a convenience.

If you challenge the any of the matters listed under 'Public Hearings' in court, you may be limited to raising only those issues you or someone else raised at the public hearing described in this notice, or in written correspondence delivered to the Brentwood City Council at, or prior to, the public hearing
NOTICE
In compliance with the Americans with Disabilities Act, the meeting room is wheelchair accessible and disabled parking is available at the City Hall parking lot. If you are a person with a disability and you need disability-related modifications or accommodations to participate in this meeting, please contact the City Clerk's Office at (925) 516-5440 or fax (925) 516-5441. Notification 48 hours prior to the meeting will enable the City to make reasonable arrangements to ensure accessibility to this meeting. {28 CFR 35.102-35, 104 ADA Title II}

POSTING STATEMENT
On February 6, 2026, a true and correct copy of this agenda was posted on the City Hall Bulletin Board, outside City Hall, 150 City Park Way, Brentwood, CA 94513 and at our website www.brentwoodca.gov
A complete packet of information is available for public review at City Hall or on our website at www.brentwoodca.gov

1 SPECIAL CITY COUNCIL MINUTES
January 27, 2026, 6:00 p.m.

A. CALL TO ORDER & ROLL CALL
Mayor Meyer called the meeting to order at 6:01 p.m.

Roll Call found the following members present: Maloney, Pierson, Mendoza, Oerlemans, and Mayor Meyer.

Vice Mayor Pierson participated remotely via Zoom under the just cause provision of Government Code § 54953.8.3.(c)(3).

B. PLEDGE OF ALLEGIANCE
Mayor Meyer led the Pledge of Allegiance.

C. PUBLIC COMMENTS
Mayor Meyer opened public comments.

Danny Dohrmann provided comments regarding the Brentwood Police Department's interaction with Yolanda Ramirez on September 26, 2025.

There being no additional speakers, Mayor Meyer closed public comments.

D. RECESS TO CLOSED SESSION
Moved by: Faye Maloney, Council Member
Seconded by: Tony Oerlemans, Council Member
The Council, by motion, recessed to Closed Session at 6:07 p.m.

Roll Call Vote:

Ayes (5): Jovita Mendoza, Council Member, Susannah Meyer, Mayor, Pa'tanisha Pierson, Vice Mayor, Tony Oerlemans, Council Member, and Faye Maloney, Council Member
Motion Approved (5 to 0)
E. BUSINESS ITEMS
E.1 CONFERENCE WITH LABOR NEGOTIATORS
E.2 PUBLIC EMPLOYEE PERFORMANCE EVALUATION
E.3 CONFERENCE WITH LEGAL COUNSEL - ANTICIPATED LITIGATION

2 F. ADJOURNMENT
The Council reconvened from Closed Session at 7:37 p.m.

Mayor Meyer stated there was nothing to report out from Closed Session.

Moved by: Jovita Mendoza, Council Member
Seconded by: Faye Maloney, Council Member
The Council, by motion, moved to adjourn at 7:37 p.m.

Roll Call Vote:

Ayes (4): Jovita Mendoza, Council Member, Susannah Meyer, Mayor, Tony Oerlemans, Council Member, and Faye Maloney, Council Member Absent (1): Pa'tanisha Pierson, Vice Mayor
Motion Approved (4 to 0)

1 CITY COUNCIL/SUCCESSOR AGENCY MINUTES
January 27, 2026, 7:00 p.m.

A. CALL TO ORDER & ROLL CALL
Mayor Meyer called the meeting to order at 7:38 p.m.

Roll Call found the following members present: Maloney, Mendoza, Oerlemans, and Mayor Meyer with Vice Mayor Pierson found absent.

Vice Mayor Pierson joined via Zoom at 7:40 p.m. and participated remotely under the just cause provision of Government Code § 54953.8.3.(c)(3).

B. PLEDGE OF ALLEGIANCE
Mayor Meyer led the Pledge of Allegiance.

C. PUBLIC COMMENTS
Mayor Meyer opened public comments.

Youth Commissioner, Sahil Narula provided updates on the Youth Commission recent accomplishments and upcoming events.

Melissa van Ruiten provided comments urging Council members to support Assembly Bill AB1633.

Ree Satti provided updates from the Brentwood Library.

Oxsana provided comments requesting that the Council pass policy addressing hate speech.

Sinziana Todor provided comments regarding District 2 Council representation.

Danny Dohrmann provided comments requesting clarity on the City's garbage / organics waste pickup services.

Tracy Kasamoto and Ron P. provided comments regarding the East County Service Center.

There being no additional speakers, Mayor Meyer closed public comments.

D. PRESENTATIONS
D.1 East County Service Center Update
Eric Angstadt, Chief Assistant County Administrator presented on the East County Service Center.

2 E. INFORMATIONAL REPORTS FROM COUNCIL MEMBERS, COMMITTEES,

LIAISONS, AND STAFF
Vice Mayor Pierson reported on attendance at the Martin Luther King Prayer Breakfast; Rock Church's nine-year anniversary celebration and dedication of their new building; and the Downtown Brentwood Coalition's Crab Feed fundraiser. Vice Mayor Pierson stated that the electric pole at Big Basin Drive and O'Hara Avenue will possibly be moved this summer; City staff will investigate the lights going half on near O'Hara Avenue and Sand Creek Road, as well as the greenery intended at the same intersection around the Public Art and Design Academy's art installation.

Council Member Mendoza reported on attendance at League of California Cities roundtable regarding Economic Development; met with local Rabbi; Contra Costa County's District 5 Supervisor, Shanelle Scales-Preston's Crab Feed fundraiser; The Lounge's three-year anniversary; Downtown Brentwood Coalition member's meeting; League of California Cities roundtable regarding e-bike regulations; League of California Cities Academy; Brentwood Police Department's Employee Recognition Dinner; Downtown Brentwood Coalition's Crab Feed fundraiser; VRNexGEN's Grand Opening; Contra Costa Rapid Response training; Urban League of the Greater Bay Area's State of the Black Base Survey and Gubernatorial Forum; and a Fire Severity Zone meeting at Trilogy.

Council Member Oerlemans reported on attendance at Tri-Delta Transit Agenda Review; Brentwood Police Department's Employee Recognition Dinner; Rock Church's nine-year anniversary celebration and dedication of their new building; meeting with Brentwood Veterans regarding the construction of the Fire Station and parking / fencing concerns; Police Activities League Crab Feed Fundraiser meeting; and the Special City Council Closed Session meeting.

Council Member Maloney reported on attendance at a human trafficking fundraising event for Community Violence Solutions; Martin Luther King Prayer Breakfast; Brentwood Police Department's Employee Recognition Dinner; Downtown Brentwood Coalition's Crab Feed fundraiser; League of California Cities Academy. Council Member Maloney reported that she was appointed by the League of California Cities to serve on the Community Services Committee and the Public Safety Policy Committee.

Mayor Meyer reported on attendance at the League of California Cities roundtable regarding Economic Development; The Lounge's three-year anniversary; Martin Luther King Jr. Day of Service Clean-up at Creekside Park; League of California Cities roundtable regarding e-bike regulations; gave a tour of City Hall to a group of Cub-Scouts; Planning Meeting for City of Brentwood's Community Day of Service; met with East County Valkyrie Girls Flag Football; Brentwood Police Department's Employee Recognition Dinner; Downtown Brentwood Coalition's Crab Feed fundraiser; Contra Costa Rapid Response training; and the Urban League of the Greater Bay Area's State of the Black Base Survey and Gubernatorial Forum.

3 F. CONSENT CALENDAR
Moved by: Faye Maloney, Council Member
Seconded by: Pa'tanisha Pierson, Vice Mayor
By motion, adopted the Consent Calendar as recommended by staff.

Roll Call Vote:

Ayes (5): Jovita Mendoza, Council Member, Susannah Meyer, Mayor, Pa'tanisha Pierson, Vice Mayor, Tony Oerlemans, Council Member, and Faye Maloney, Council Member
Motion Approved (5 to 0)
F.1 Meeting Minutes of the City Council
Approved meeting minutes of the Special City Council Meeting Minutes of January 13, 2026 and the City Council / Successor Agency Meeting Minutes of January 13, 2026.

F.2 Proclamation recognizing February 2026 as American Heart Month By Proclamation, the Council recognized February 2026 as American Heart Month.

F.3 Proclamation recognizing February 2026 as Black History Month By Proclamation, the Council recognized February 2026 as Black History Month.

Mayor Meyer presented the proclamation to GiGi Crowder, Chief Executive Officer for National Alliance on Mental Illness Contra Costa and Jessica Eastman Stewart and Anitra Simpson with the Brentwood Black History Month Oratorical Committee.

F.4 Proclamation recognizing February 2026 as National Cancer Prevention Month
By Proclamation, the Council recognized February 2026 as National Cancer Prevention Month.

F.5 Proclamation recognizing February 8-14, 2026 as Future Business Leaders of America Week
By Proclamation, the Council recognized February 8-14, 2026 as Future Business Leaders of America Week.

Mayor Meyer presented the proclamation to Ian Cohen and Mark Tinder with the Future Business Leaders of America, Brentwood Chapter.

4 G. PUBLIC HEARINGS
G.1 Hold a public hearing and confirm the annexation of territory to Landscape and Lighting Assessment District No. 23-1 (Orchard Grove) The Council recessed at 9:52 p.m. and reconvened at 10:04 p.m.

Harith Aleem, Director of Parks and Recreation presented the item.

Mayor Meyer opened the public hearing.

There being no one wishing to speak, Council Member Mendoza moved to close the public hearing, seconded by Council Member Maloney.

The motion to close the public hearing carried unanimously by roll call vote with Council Member Maloney, Council Member Mendoza, Vice Mayor Pierson, Council Member Oerlemans and Mayor Meyer in favor.

City Clerk, Amanda McVey, tallied the votes and confirmed the vote was unanimous with no majority protests to the annexation of territory (Annexation No. 1) to existing Landscape and Lighting Assessment District (‘LLAD’) No. 23-1 (Orchard Grove) based on the tabulation of the returned ballots, weighted by assessment amount.

Moved by: Faye Maloney, Council Member
Seconded by: Jovita Mendoza, Council Member
By motion, confirmed there were no majority protests to the annexation of territory (Annexation No. 1) to existing Landscape and Lighting Assessment District (‘LLAD’) No. 23-1 (Orchard Grove) based on the tabulation of the returned ballots, weighted by assessment amount.

Roll Call Vote:

Ayes (5): Jovita Mendoza, Council Member, Susannah Meyer, Mayor, Pa'tanisha Pierson, Vice Mayor, Tony Oerlemans, Council Member, and Faye Maloney, Council Member
Motion Approved (5 to 0)
Moved by: Tony Oerlemans, Council Member
Seconded by: Jovita Mendoza, Council Member
Adopted Resolution No. 2026-04 ordering the annexation of territory to LLAD No. 23-1 (Orchard Grove) as Annexation No. 1 and ordering improvements and confirming the diagram and assessments as shown in the LLAD No. 23-1 (Orchard Grove) Fiscal Year 2025-26 Final Engineer’s Report in accordance with provisions of the Streets and Highway Code “Landscape and Lighting Act of 1972” and California Proposition 218.

5 Roll Call Vote:

Ayes (5): Jovita Mendoza, Council Member, Susannah Meyer, Mayor, Pa'tanisha Pierson, Vice Mayor, Tony Oerlemans, Council Member, and Faye Maloney, Council Member
Motion Approved (5 to 0)
H. BUSINESS ITEMS
H.1 Direction Regarding City Comments on BLM Oil and Gas Leasing and Development
Alexis Morris, Director of Community Development presented the item.

Mayor Meyer opened public comments.

Melissa van Ruiten, Tracy Kasamoto, and Sinziana Todor provided comments in opposition to oil and gas leasing and development.

Oxsana provided comments questioning the ownership of mineral rights vs. land rights for some of the parcels surrounding Brentwood that are shown in the Supplemental Environmental Impact Statement document.

There being no additional speakers, Mayor Meyer closed public comments.

Moved by: Jovita Mendoza, Council Member
Seconded by: Susannah Meyer, Mayor
By motion, directed staff to compose a letter expressing the Council's concern over the health and safety of Brentwood's neighboring communities and in opposition of Bureau and Land Management's Oil and Gas Leasing and Development on public lands in the Central Coast Field Office planning area (including Contra Costa County).

Roll Call Vote:

Ayes (5): Jovita Mendoza, Council Member, Susannah Meyer, Mayor, Pa'tanisha Pierson, Vice Mayor, Tony Oerlemans, Council Member, and Faye Maloney, Council Member
Motion Approved (5 to 0)
H.2 2025/26 Mid-year Operating Budget Amendments and ten-year General Fund Fiscal Model update
Christine Andrews, Acting Finance and Information Systems Director presented the item.

Mayor Meyer opened public comments.

6 Tracy Kasamoto expressed concerns about the State's mandated housing requirements and the City's ability to anticipate 10-year budget projections.

Sinziana Todor expressed her appreciation for the Finance staff and requested to have additional funds directed towards road improvements.

There being no additional speakers, Mayor Meyer closed public comments.

Moved by: Tony Oerlemans, Council Member
Seconded by: Faye Maloney, Council Member
Adopted Resolution 2026-05 amending the 2025/26 Operating Budget.

Roll Call Vote:

Ayes (5): Jovita Mendoza, Council Member, Susannah Meyer, Mayor, Pa'tanisha Pierson, Vice Mayor, Tony Oerlemans, Council Member, and Faye Maloney, Council Member
Motion Approved (5 to 0)
H.3 Authorizing the Execution of Agreements and Necessary Documents for Ongoing and/or Recurring Purchases with Specified Vendors for Fiscal Year 2025/26
Michelle Inglis, Management Analyst presented the item.

Mayor Meyer opened public comments.

There being no one wishing to speak, Mayor Meyer closed public comments.

Moved by: Jovita Mendoza, Council Member
Seconded by: Tony Oerlemans, Council Member
Adopted joint Resolution 2026-06 / Resolution 2026-02-SA approving and authorizing the City Manager or City Attorney and Executive Director or General Counsel, or designees, as appropriate, to execute certain agreements, amendments, purchase orders and/or change orders that have anticipated spending over $50,000 (City Manager and Executive Director) and $75,000 (City Attorney and General Counsel, limited to legal services and personnel investigative services) for Fiscal Year 2025/26, after consideration of approval as to form by the City Attorney or General Counsel.

Roll Call Vote:

Ayes (5): Jovita Mendoza, Council Member, Susannah Meyer, Mayor, Pa'tanisha Pierson, Vice Mayor, Tony Oerlemans, Council Member, and Faye Maloney, Council Member
Motion Approved (5 to 0)

7 H.4 Update on the Memorandum of Understanding between the City and Downtown Brentwood Coalition
Abraham Salinas, Senior Analyst and Kristen Mingus, Executive Director of Downtown Brentwood Coalition ("DBC") presented the item.

Mayor Meyer opened public comments.

Five written comments were received by the City Clerk’s office in advance of the City Council meeting in support of the item from: Joey and Suzanne Nardone; Julie Deck; Becky Bloomfield; Kimberly Mello and Matt Schwab.

Amy, Lynn, Dee Olmedo, Emil Geddes, Roberta Byas, Christian PoncoGomez, Randi Moser, Genevieve DeBarhlo, Vicky Little, Savino Ruvalcaber, Oxsana, Mike Kleeman, Greg Robinson, Matt Schwab, Sinziana Todor, Dorina Moraida, Matt Hagar, and Marivel provided comments in support of the City renewing a Memorandum of Understanding with the DBC.

There being no additional speakers, Mayor Meyer closed public comments.

Moved by: Jovita Mendoza, Council Member
Seconded by: Pa'tanisha Pierson, Vice Mayor
By motion, directed staff to develop and return to Council a new Memorandum of Understanding between the City of Brentwood and the Downtown Brentwood Coalition for fiscal years 2026-27 and 2027-28 in the amount of $90,000 per fiscal year.

Roll Call Vote:

Ayes (5): Jovita Mendoza, Council Member, Susannah Meyer, Mayor, Pa'tanisha Pierson, Vice Mayor, Tony Oerlemans, Council Member, and Faye Maloney, Council Member
Motion Approved (5 to 0)
H.5 Authorize the City Manager or designee to execute a Professional Services Agreement with Kimley Horn & Associates, Inc., for the Engineering Design Services for the Lone Tree Way-Union Pacific AtGrade Crossing - CIP Project No. 336-31340 Anju Pillai, Engineering Manager presented the item.

Mayor Meyer opened public comments.

Sinziana Todor provided comments in opposition of redirecting funds from the Innovation Center to this project.

There being no additional speakers, Mayor Meyer closed public comments.

8 Moved by: Faye Maloney, Council Member
Seconded by: Susannah Meyer, Mayor
Adopted Resolution 2026-07: 1) Approving and authorizing the City Manager or designee to execute a Professional Services Agreement (“Agreement”) with Kimley Horn & Associates, Inc., for Engineering Design Services in the amount of $1,104,755, plus funding authorization for a 10% contingency of $110,476, for a total funding authorization not-to-exceed amount of $1,215,231 for the Lone Tree Way - Union Pacific At-Grade Crossing, CIP Project No. 336-31340 (“Project”); 2) amending the 2025/26 – 2029/30 Capital Improvement Program (“CIP”); and 3) amending the 2025/26 Operating Budget for the associated Project funding transfer.

Roll Call Vote:

Ayes (5): Jovita Mendoza, Council Member, Susannah Meyer, Mayor, Pa'tanisha Pierson, Vice Mayor, Tony Oerlemans, Council Member, and Faye Maloney, Council Member
Motion Approved (5 to 0)
I. REQUEST FOR FUTURE AGENDA ITEMS - NEW REQUEST(S)
There were no requests for Future Agenda Items.

J. REQUESTED FUTURE AGENDA ITEM(S)
J.1 Consider a request from Vice Mayor Pierson and Council Member Maloney Regarding Tourism Strategies Related to Major Sporting Events in the Bay Area
Mayor Meyer opened public comments.

There being no one wishing to speak, Mayor Meyer closed public comments.

Moved by: Faye Maloney, Council Member
Seconded by: Pa'tanisha Pierson, Vice Mayor
By motion, directed staff to spend time and resources to develop a tourism strategy focusing on day experiences in collaboration with Bay Area Host Committee and local stakeholders and to return to Council no later than March 10, 2026.

Roll Call Vote:

Ayes (5): Jovita Mendoza, Council Member, Susannah Meyer, Mayor, Pa'tanisha Pierson, Vice Mayor, Tony Oerlemans, Council Member, and Faye Maloney, Council Member
Motion Approved (5 to 0)

9 K. ADJOURNMENT
By motion, adjourned at 12:01 a.m. on January 28, 2026.

Roll Call Vote:

Ayes (5): Jovita Mendoza, Council Member, Susannah Meyer, Mayor, Pa'tanisha Pierson, Vice Mayor, Tony Oerlemans, Council Member, and Faye Maloney, Council Member
Motion Approved (5 to 0)

CITY COUNCIL AGENDA ITEM NO. H.1
02/10/2026
SUBJECT: Award of contract to Mountain Cascade Inc. for the Municipal Services Center Pavement Rehab
DEPARTMENT: Public Works
STAFF: Casey Wichert, Director of Public Works
Christopher Ziemann, Assistant Director of Public Works

TITLE/RECOMMENDATION
Adopt a Resolution approving the contract documents, awarding the bid, and authorizing the City Manager or designee to execute a contract and necessary documents for the Municipal Services Center Pavement Rehab (“Project”) with Mountain Cascade Inc. as the lowest responsible and responsive bidder in the amount of $341,860.00, plus funding authorization for a 15% contingency of $51,279.00, for a total funding authorization not-to-exceed amount of $393,139.00.

Per 14 CCR § 15062, a CEQA Notice of Exemption was filed with the Contra Costa County Clerk Recorder on January 15, 2026.

FISCAL IMPACT
If approved, the total cost of the contract with Mountain Cascade for the solid waste facility pavement rehabilitation is $341,860.00, plus funding authorization for a 15% contingency of $51,279.00, for a total funding authorization not-to-exceed amount of $393,139.00.

The funds for the contract amount are available in the 2025/26 Solid Waste Enterprise Operating Budget.

BACKGROUND
The City’s Municipal Services Center (“MSC”) serves as a critical operations hub for the City of Brentwood, supporting Public Works, Solid Waste, and other municipal services. The MSC houses the Solid Waste Transfer Station where trash and recyclables are dropped off, sorted, and consolidated, then loaded onto larger trucks for transport to a landfill, recycling center, or other disposal facility. Public Works operates an average of 13-14 garbage truck routes each day within Brentwood. Each

CITY COUNCIL AGENDA ITEM NO. H.1
02/10/2026
truck route transports multiple loads of trash, recyclables, and organics to the Solid Waste Transportation Station where they are sorted and consolidated prior to being transferred to landfills or other disposal facilities by fully loaded semi-trucks that weigh up to 78,000 pounds each.

Due to the extensive use of heavy vehicles, the pavement and parking areas around the Solid Waste Transfer Station have deteriorated over time and currently exhibit severe signs of distress and failure, including cracking, surface deterioration, base failures, and structural weakening.

The Project is located entirely within the MSC and consists of rehabilitation of existing pavement throughout the Solid Waste Transfer Station and paving of a gravel area around the Solid Waste Transfer Station. Existing pavement in the Project area has deteriorated rapidly over the last year, causing operational challenges, maintenance and drainage issues, particularly during and after rain events. This Project will improve safety, functionality, and accessibility, and will extend the useful life of the Solid Waste Transfer Station.

This Project was advertised on December 1, 2025 with an Engineer’s Estimate of $440,000, bids were opened on January 7, 2026, and the following twelve bids were received:

Contractor Bid Amount
Mountain Cascade, Inc. $341,860.00
Consolidated Engineering, Inc. $357,173.80
Knife River Construction $404,316.00
Silicon Valley Paving Inc. $414,700.70
United Pavement Maintenance $424,381.95
Tri-Valley Excavating $449,424.50
Rapid Grading Services $450,688.00
Ghilotti Bros Inc. $463,049.50
R&M Paving Contractors Inc. $504,024.40
EE Gilbert Construction Inc. $525,645.60
Goodfellow Bros $537,507.00
Apena Engineering Inc. $537,764.50
Staff reviewed the bids received and is recommending award of the contract to Mountain Cascade, Inc., for submitting the lowest responsible and responsive bid for the Project.

CITY COUNCIL AGENDA ITEM NO. H.1
02/10/2026

CITY COUNCIL STRATEGIC INITIATIVE
Focus Area 1 - Goal 2: Water, Wastewater, and Solid Waste Services: Provide safe and sustainable water, wastewater, and solid waste services for the build-out of the City per the City’s General Plan.

PREVIOUS ACTION
Previous Action by the City Council is included on Attachment 1.

DATE OF NOTICE
Not Applicable

ENVIRONMENTAL DETERMINATION
A Notice of Exemption was filed with the Contra Costa County Clerk Recorder on January 15, 2026, in accordance with 14 CCR § 15062.

ALTERNATIVE OPTION(S)

1. Do not approve staff’s recommendation.

2. Continue the item with direction for staff to return with additional information.

ATTACHMENT(S)

1. Previous Action

2. Resolution

3. Contract

PREVIOUS ACTION
Previous actions related to this agenda item that were taken by the Council are listed below. To view prior actions and materials, and Brentwood Municipal Code references in the staff report, as applicable:
 Visit www.brentwoodca.gov/meetings, and select the meeting date(s) desired to see the reference materials and videos.
 Visit www.brentwoodca.gov/municipalcode to research references to the Brentwood Municipal Code and search by the code section(s) cited.

On June 25, 2024, by Resolution No. 2024-73, the City Council adopted the 2024/25 – 2025/26 Operating Budget, which included the Municipal Services Center Pavement Rehabilitation Project.

RESOLUTION NO. 2026-XX

A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF

BRENTWOOD APPROVING THE CONTRACT DOCUMENTS,

AWARDING THE BID, AND AUTHORIZING THE CITY MANAGER

OR DESIGNEE TO EXECUTE A CONTRACT AND NECESSARY

DOCUMENTS FOR THE MUNICIPAL SERVICES CENTER
PAVEMENT REHAB (“PROJECT”) WITH MOUNTAIN CASCADE
INC. AS THE LOWEST RESPONSIBLE AND RESPONSIVE BIDDER
IN THE AMOUNT OF $341,860.00, PLUS FUNDING
AUTHORIZATION FOR A 15% CONTINGENCY OF $51,279.00,

FOR A TOTAL FUNDING AUTHORIZATION NOT-TO-EXCEED
AMOUNT OF $393,139.00
WHEREAS, the City’s Municipal Services Center (“MSC”) serves as a critical operations hub for the City of Brentwood, supporting Public Works, Solid Waste, and other municipal services; and
WHEREAS, the MSC houses the Solid Waste Transfer Station where trash and recyclables are dropped off, sorted or consolidated, then loaded onto larger trucks for transport to a landfill, recycling center, or other disposal facility; and WHEREAS, due to the extensive use of heavy vehicles, the pavement and parking areas around the Solid Waste Transfer Station have deteriorated over time and currently exhibit severe signs of distress and failure, including cracking, surface deterioration, base failures, and structural weakening; and WHEREAS, the Municipal Services Center Pavement Rehabilitation Project (the “Project”) will rehabilitate existing pavement throughout the Solid Waste Transfer Station and paving of a gravel area around the Solid Waste Transfer Station at the MSC; and
WHEREAS, the Project will improve safety, functionality, and accessibility, and will extend the useful life of the Solid Waste Transfer Station; and WHEREAS, the Project was advertised on December 1, 2025, with an Engineer’s Estimate of $440,000, bids were opened on January 7, 2026, and the following twelve bids were received; and
Contractor Bid Amount
Mountain Cascade, Inc. $341,860.00
Consolidated Engineering, Inc. $357,173.80
Knife River Construction $404,316.00
Silicon Valley Paving Inc. $414,700.70

Contractor Bid Amount
United Pavement Maintenance $424,381.95
Tri-Valley Excavating $449,424.50
Rapid Grading Services $450,688.00
Ghilotti Bros Inc. $463,049.50
R&M Paving Contractors Inc. $504,024.40
EE Gilbert Construction Inc. $525,645.60
Goodfellow Bros $537,507.00
Apena Engineering Inc. $537,764.50
WHEREAS, the cost of the contract with Mountain Cascade, Inc., is $341,860.00, plus a funding authorization of 15% contingency of $51,279.00, for a total funding authorization not-to-exceed of $393,139.00 for the Project; and WHEREAS, there is sufficient funds for the Project within the 2025/26 Solid Waste Enterprise Operating Budget to award the cost of the contract plus a 15% contingency.

NOW, THEREFORE, BE IT RESOLVED that the City Council of the City of Brentwood does hereby award the contract to Mountain Cascade, Inc. as the lowest responsible and responsive bidder in the amount of $341,860.00; authorizes a 15% contingency in the amount of $51,279.00, for a total funding authorization not-toexceed amount of $393,139.00; and authorizes the City Manager or designee to execute a Public Works Contract and necessary documents with Mountain Cascade, Inc.

PASSED, APPROVED, AND ADOPTED by the City Council of the City of Brentwood at a regular meeting held on the 10th day of February 2026 by the following vote:

Contract
This public works contract (“Contract”) is entered into by and between the City of Brentwood (“City”) and Mountain Cascade Inc. (“Contractor”), for work on the Municipal Services Center Pavement Rehab (“Project”).

The parties agree as follows:

1. Award of Contract. In response to the Notice Inviting Bids, Contractor has submitted a Bid Proposal to perform the Work to construct the Project. On February 10, 2026, City authorized award of this Contract to Contractor for the amount set forth in Section 4, below. City has elected to include the following Project alternate(s) in the Contract: No Alternates

2. Contract Documents. The Contract Documents incorporated into this Contract include and are comprised of all of the documents listed below. The definitions provided in Article 1 of the General Conditions apply to all of the Contract Documents, including this Contract.

2.1 Notice Inviting Bids;

2.2 Instructions to Bidders;

2.3 Addenda, if any;

2.4 Bid Proposal and attachments thereto;

2.5 Contract;

2.6 Payment and Performance Bonds;

2.7 General Conditions;

2.8 Special Conditions;

2.9 Project Plans and Specifications;

2.10 Change Orders, if any;

2.11 Notice of Potential Award;

2.12 Notice to Proceed; and

2.13 The following: No other documents

3. Contractor’s Obligations. Contractor will perform all of the Work required for the Project, as specified in the Contract Documents. Contractor must provide, furnish, and supply all things necessary and incidental for the timely performance and completion of the Work, including all necessary labor, materials, supplies, tools, equipment, transportation, onsite facilities, and utilities, unless otherwise specified in the Contract Documents. Contractor must use its best efforts to diligently prosecute and complete the Work in a professional and expeditious manner and to meet or exceed the performance standards required by the Contract Documents.

4. Payment. As full and complete compensation for Contractor’s timely performance and completion of the Work in strict accordance with the terms and conditions of the Contract Documents, City will pay Contractor $341,860.00 (“Contract Price”) for all of Contractor’s direct and indirect costs to perform the Work, including all labor, materials, supplies, equipment, taxes, insurance, bonds and all overhead costs, in accordance with the payment provisions in the General Conditions.

5. Time for Completion. Contractor will fully complete the Work for the Project, meeting all requirements for Final Completion, within 25 calendar days from the start date set forth in the Notice to Proceed (“Contract Time”). By signing below, Contractor expressly waives any claim for delayed early completion.

6. Liquidated Damages. As further specified in Section 5.4 of the General Conditions, if Contractor fails to complete the Work within the Contract Time, City will assess liquidated damages in the amount of $2,500 per day for each day of unexcused delay in achieving Final Completion, and such liquidated damages may be deducted from City’s payments due or to become due to Contractor under this Contract.

7. Labor Code Compliance.

7.1 General. This Contract is subject to all applicable requirements of Chapter 1 of Part 7 of Division 2 of the Labor Code, including requirements pertaining to wages, working hours and workers’ compensation insurance, as further specified in Article 9 of the General Conditions.

7.2 Prevailing Wages. This Project is subject to the prevailing wage requirements applicable to the locality in which the Work is to be performed for each craft, classification or type of worker needed to perform the Work, including employer payments for health and welfare, pension, vacation, apprenticeship and similar purposes. Copies of these prevailing rates are available online at http://www.dir.ca.gov/DLSR.

7.3 DIR Registration. City may not enter into the Contract with a bidder without proof that the bidder and its Subcontractors are registered with the California Department of Industrial Relations to perform public work pursuant to Labor Code § 1725.5, subject to limited legal exceptions.

8. Workers’ Compensation Certification. Pursuant to Labor Code § 1861, by signing this Contract, Contractor certifies as follows: “I am aware of the provisions of Labor Code § 3700 which require every employer to be insured against liability for workers’ compensation or to undertake selfinsurance in accordance with the provisions of that code, and I will comply with such provisions before commencing the performance of the Work on this Contract.”

9. Conflicts of Interest. Contractor, its employees, Subcontractors, and agents may not have, maintain, or acquire a conflict of interest in relation to this Contract in violation of any City ordinance or requirement, or in violation of any California law, including Government Code § 1090 et seq., or the Political Reform Act, as set forth in Government Code § 81000 et seq. and its accompanying regulations. Any violation of this Section constitutes a material breach of the Contract.

10. Independent Contractor. Contractor is an independent contractor under this Contract and will have control of the Work and the means and methods by which it is performed. Contractor and its Subcontractors are not employees of City and are not entitled to participate in any health, retirement, or any other employee benefits from City.

11. Notice. Any notice, billing, or payment required by or pursuant to the Contract Documents must be made in writing, signed, dated, and sent to the other party by personal delivery, U.S. Mail, a reliable overnight delivery service, or by email as a PDF file. Notice is deemed effective upon delivery, except that service by U.S. Mail is deemed effective on the second working day after deposit for delivery. Notice for each party must be given as follows:

City:

City of Brentwood
Engineering Department
150 City Park Way, Brentwood, CA 94513
925.516.5420
Attn: Brant Wilson, PE, Senior Associate Engineer
[email protected]

Contractor:

Name: Mountain Cascade Inc.

Address: P.O. Box 5050
City/State/Zip: Livermore, CA 94551
Phone: 925-373-8370
Attn: David Hicks
Email: [email protected]

12. General Provisions.

12.1 Assignment and Successors. Contractor may not assign its rights or obligations under this Contract, in part or in whole, without City’s written consent. This Contract is binding on Contractor’s and City’s lawful heirs, successors and permitted assigns.

12.2 Third Party Beneficiaries. There are no intended third party beneficiaries to this Contract.

12.3 Governing Law and Venue. This Contract will be governed by California law and venue will be in the Contra Costa County Superior Court, and no other place. Contractor waives any right it may have pursuant to Code of Civil Procedure § 394, to file a motion to transfer any action arising from or relating to this Contract to a venue outside of Contra Costa County, California.

12.4 Amendment. No amendment or modification of this Contract will be binding unless it is in a writing duly authorized and signed by the parties to this Contract.

12.5 Integration. This Contract and the Contract Documents incorporated herein, including authorized amendments or Change Orders thereto, constitute the final, complete, and exclusive terms of the agreement between City and Contractor.

12.6 Severability. If any provision of the Contract Documents is determined to be illegal, invalid, or unenforceable, in whole or in part, the remaining provisions of the Contract Documents will remain in full force and effect.

12.7 Iran Contracting Act. If the Contract Price exceeds $1,000,000, Contractor certifies, by signing below, that it is not identified on a list created under the Iran Contracting Act, Public Contract Code § 2200 et seq. (the “Act”), as a person engaging in investment activities in Iran, as defined in the Act, or is otherwise expressly exempt under the Act.

12.8 Authorization. Each individual signing below warrants that he or she is authorized to do so by the party that he or she represents, and that this Contract is legally binding on that party. If Contractor is a corporation, signatures from two officers of the corporation are required pursuant to California Corporations Code § 313.

12.9 Digital/Electronic Signatures. Using a City-approved method, this Contract may be executed through the use of digital or electronic signatures in accordance with Government Code Section 16.5. The presence of an electronic signature on this Contract will be construed as the Parties’ consent to do business electronically. [Signatures are on the following page.]

The parties agree to this Contract as witnessed by the signatures below:

CITY: Approved as to form:
s/_______________________________ s/__________________________________ G. Harold Duffey, City Manager ________________________, _______________ Date: ___________________________ Date: ______________________________ Attest:
s/_______________________________
Amanda McVey, City Clerk
Date: ___________________________
CONTRACTOR: Mountain Cascade, Inc.

Business Name
s/_______________________________ Seal:

Michael Duke Fuller, President/CEO
Name, Title
Date: ____________________________
Second Signature (See Section 12.8):
s/_______________________________
David Hicks, Secretary
Name, Title
Date: ____________________________
422496 EXP. 5/31/2026
___________________________________________________
Contractor’s California License Number(s) and Expiration Date(s)

END OF CONTRACT

CITY COUNCIL AGENDA ITEM NO. H.2
02/10/2026
SUBJECT: Informational Report on the East County Service Center Initial Study/Mitigated Negative Declaration and City Processes DEPARTMENT: City Manager
STAFF: Harold Duffey, City Manager
Allen Baquilar, Director of Engineering
Alexis Morris, Director of Community Development

TITLE/RECOMMENDATION
Receive informational report on the release of the Initial Study/Mitigated Negative Declaration (IS/MND) for the East County Service Center project and City processes related to the project.

FISCAL IMPACT
There is no cost associated with this item, other than staff time to read the MND and submit a comment letter to the County.

BACKGROUND
IS/MND
On January 29, 2026, the Contra Costa County Department of Conservation and Development released a Notice of Public Review and Intent (“Notice of Intent”) to Adopt a Proposed Mitigated Negative Declaration for the proposed East County Service Center project (the “Project”). The proposed Project is located on Countyowned parcels located at Brentwood Boulevard and Technology Way in the City of Brentwood. The Notice of Intent and the IS/MND are included as Attachment 1 to this report.

The public comment period on the IS/MND began February 2nd and ends February 23rd at 5:00 pm. The public may submit written comments to the following address:

Shravan Sundaram
Contra Costa County Public Works Department
255 Glacier Drive
Martinez, CA 94553
[email protected]

CITY COUNCIL AGENDA ITEM NO. H.2
02/10/2026
According to the Notice of Intent, the Initial Study:
“…identified potentially significant impacts in the environmental areas of aesthetics, air quality, biological resources, cultural resources, geology/soils, hazards and hazardous materials, noise, and tribal cultural resources. Environmental analysis determined that measures were available to mitigate potential adverse impacts to less than significant levels. As a result, a Mitigated Negative Declaration (MND) has been prepared pursuant to Public Resources Code Section 21080(c), 21064.5, and Article 6 of the California Environmental Quality Act (CEQA) Guidelines.”
City staff from multiple departments will be reviewing the IS/MND for technical accuracy and for the adequacy of mitigation measures to address potential environmental impacts in the city of Brentwood. Staff will submit a comment letter reflecting its findings by the February 23 deadline.

PROPOSED PROJECT
The proposed East County Service Center would house multiple County departments and provide a centralized service center for residents of East Contra Costa County.

The new three-story building would provide approximately 120,000 gross square feet of usable space and have a maximum height of approximately 58 feet. Project construction is anticipated to begin in early 2026 and be completed by the end of 2027, a period of approximately 20 months.

The East County Service Center would be accessed by the public from Technology Way, with staff-only gated entrances on Business Center Drive and Brentwood Boulevard. The proposed project would include approximately 409 parking stalls, including 108 EV-capable spaces, with 82 Type 2 electric vehicle (EV) chargers and 4 DC fast charging stations. The proposed project would also include 17 covered bike parking spaces for staff members and four spaces for the public. 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 project proposes the following modifications to the vehicular circulation system on Brentwood’s roadways:
• 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;

CITY COUNCIL AGENDA ITEM NO. H.2
02/10/2026
• 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.

The project is located in the city of Brentwood, however, the City has limited authority over the project because it is located on parcels owned by the County. Under the Government Code (Sections 53090, et seq.), counties are exempt from all city planning and zoning requirements on county-owned land within the city. Counties developing their own property within a city are still subject to:
• state standards, such as the Building Standards Law;
• compliance with the California Environmental Quality Act (CEQA), which cities are free to comment on through the public comment process; and • the Subdivision Map Act, if the county project is acting in a proprietary capacity.

The City does have the authority to take action on the following items:
 Encroachment permit: this is a ministerial permit granted by the City for improvements in the City’s right of way;
 General Plan conformance determination: county public works projects, acquisition or disposition of public property, and construction of public buildings can be reviewed by the Planning Commission for conformance with the General Plan; although the findings of the City either way are advisory only and would not prohibit the county’s project.

CITY COUNCIL STRATEGIC INITIATIVE
Not applicable.

PREVIOUS ACTION
Not applicable

DATE OF NOTICE
Not applicable.

CITY COUNCIL AGENDA ITEM NO. H.2
02/10/2026

ENVIRONMENTAL DETERMINATION
Not applicable.

ALTERNATIVE OPTION(S)
Not applicable.

ATTACHMENT(S)

1. January 29, 2026, Notice of Intent and attached Initial Study Mitigated Negative Declaration.

Contra
Costa
County
January 29, 2026

NOTICE OF PUBLIC REVIEW AND INTENT TO ADOPT A PROPOSED

MITIGATED NEGATIVE DECLARATION
Pursuant to the State of California Public Resources Code and the "Guidelines for Implementation of the California Environmental Quality Act of 1970" as amended to date, this is to advise you that the Contra Costa County Department of Conservation and Development, Community Development Division, has prepared an initial study evaluating the potential environmental impacts of the following project:

1. Project Title: East County Service Center Project

2. County File Number: CP#25-39, Project No. WH429A

3. Lead Agency: Contra Costa County
Department of Conservation and Development
30 Muir Road, Martinez, CA 94553

4. Lead Agency Contact Person: Syd Sotoodeh, Senior Planner (925) 655-2877
[email protected]

5. Project Location: The approximately 7.86-acre project site is located along Technology Way south of Sand Creek Road,
between Business Circle Drive and Brentwood
Boulevard, in Brentwood (Assessor’s Parcel Numbers
[APNs] 016-410-008, 016-410-009, 016-410-010, 016-
410-011, 016-410-012, 016-410-013, and 016-120-
024).

6. Applicant: Contra Costa County Public Works Department Contact: Shravan Sundaram, (925) 313-2366
255 Glacier Drive, Martinez, CA 94553
John Kopchik
Director
Jason Crapo
Deputy Director
Deidra Dingman
Deputy Director
Ruben Hernandez
Deputy Director
Gabriel Lemus
Deputy Director
Department of
Conservation and
Development
30 Muir Road
Martinez, CA 94553
Phone:1-855-323-2626

7. Description of Project:

The County proposes construction of a new East County Service Center (proposed project) at Technology Way and Brentwood Boulevard in the city of Brentwood, East Contra Costa County (see Figure 1). The project site is a flat, grassy undeveloped lot with no trees, buildings, or utilities. A gravel staging area exists in the northwest portion of the project site.

The new facility would house multiple County departments and provide a centralized service center for residents of East Contra Costa County, which is one of the fastest-growing regions within the county. The new three-story building would provide approximately 120,000 gross square feet of usable space and have a maximum height of approximately 58 feet, including the mechanical penthouse and mechanical roof equipment (see Figures 2 and 3). The building would include a lobby area, administrative offices for approximately 10 County departments, conference rooms, building support rooms, and other amenities. There will be two main entrances to the lobby area: one for the public and one for staff only. Additionally, there will be four entrances on the side of the building: two for the public and two for staff only. Sixteen restrooms are proposed, including 6 for the public and 10 for staff use. Two public elevators, two staff-only elevators, and three stair towers (one with roof access) would provide access to the upper floors. One open staircase would lead from the main lobby to the second-level lobby area. The on-site staff would have access to the roof terraces on the second and third levels; the terraces would have a pedestal paver system. Table 1-1 provides an overview of the proposed project.

Table 1-1: Proposed Project Overview
Feature Overview
Project Site 7.86 acres at Technology Way and Brentwood Boulevard in the city of Brentwood
Building Gross
Square Footage
120,000 gross square feet
Building Height 3 stories
Approximately 58 feet high, including the mechanical penthouse and mechanical roof equipment
Employees Approximately 441 County staff members
Vehicular Parking 409 parking stalls (286 for staff, 79 for visitors, and 44 for fleet vehicles) Bicycle Parking 58 spaces (22 long-term spaces and 36 short-term spaces) Sustainability Leadership in Energy and Environmental Design (LEED) Silver rating, at a minimum
The building is designed with a mass timber super structure and with glass-fiber reinforced concrete exterior siding. There is a glass curtain wall system in prime locations on the building façade for enhanced natural light and views, supplemented by punched windows in all other locations. The project will employ metal panel cladding siding in a few locations with metal fin architectural accents: this vocabulary complements other modern County buildings.

The proposed project would be fully electric and includes a rooftop photovoltaic system to supply on-site renewable energy. The photovoltaic system would be connected to an approximately 688-kilowatt battery back-up system. The battery back-up system would be located in the vehicle parking area south of the proposed building. In addition, the proposed building would include a hybrid heating, ventilation, and air-conditioning (HVAC) system consisting of both a geothermal system and a heat pump. The geothermal system would include

approximately 60 wells which would be drilled down to a maximum of 400 feet. The wells would contain HVAC piping that carries fluid to depth for heat transfer with the ground, allowing for energy efficient heating and cooling. The pumphouse would be located west of the proposed building and the wells would be located throughout the vehicle parking areas. The heat pump would be located on the roof of the proposed building. The proposed project would achieve, at a minimum, a Leadership in Energy and Environmental Design (LEED) Silver rating.

The project site would be developed with stormwater treatment basins, pedestrian walkways, and a public plaza along the north façade that would wrap around the corner entry. These treatment features are expected to decrease the rate and volume of stormwater runoff. A trellis or gazebo would be provided for outdoor functions. A covered area outside the conference rooms would be located at the east end of the building. There would be a 180-foot passenger drop-off zone with permeable pavers running parallel to the public plaza on the north side of the building adjacent to a secure child play area. An approximately 8-foot-tall fence would be installed along the perimeter of the staff and fleet vehicle parking areas and at the east end of the building.

Regarding site improvements, the proposed project would include approximately 43,000 square feet of concrete paving, 10,000 square feet of sidewalk, and 1,200 linear feet of curbing.

Regarding roadways and parking, the proposed project would include approximately 160,000 square feet of asphalt concrete paving, 11,000 linear feet of concrete curbing, and 500 square feet of permeable pavers. A planned public plaza and right-of-way planting would require approximately 42,000 square feet of paving. Landscaping is planned for approximately 28,000 square feet of the project site. New plantings would include a mix of native, drought-tolerant plants. There are currently no trees on the project site; thus, the proposed project would not require the removal of any trees.

Access and Parking
The East County Service Center would be accessed by the public from Technology Way, with staff-only gated entrances on Business Center Drive and Brentwood Boulevard.

The proposed project would include approximately 409 parking stalls, with 286 stalls for employees, 79 stalls for visitors, and 44 stalls for fleet vehicles (see Figure 2 and Table 1-1).

The project would include 108 EV-capable spaces, with 82 Type 2 electric vehicle (EV) chargers and 4 DC fast charging stations. The proposed project would also include 17 covered bike parking spaces for staff members and four spaces for the public. In addition, the proposed project would include the following modifications to the vehicular circulation system on public roadways in the vicinity:
• 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., access points, modifications to the circulation system, utility connections, etc.) within the public right-of-way would be constructed to comply with City standards.

Occupancy
The proposed project would result in approximately 441 County employees working at the project site, including approximately 150 relocated employees from other County facilities.

Construction Schedule and Construction Activities
Project construction is anticipated to begin in early 2026 and be completed by the end of 2027, a period of approximately 20 months. The phases of project construction include:
• Phase 1: Site mobilization and site preparation, which would take approximately 1 month.
• Phase 2: Rough grading, site utilities, and geothermal work, which would take approximately 10 weeks.
• Phase 3: Foundations, which would take approximately 6 weeks. • Phase 4: Construction of the building, which would take approximately 15 months. • Phase 5: Paving and landscaping, which would take approximately 1 month. • Phase 6: Application of architectural coatings, which would take approximately 1 month.

Construction grading is anticipated to affect the entire project site (i.e., approximately 7.86 acres, or 340,000 square feet). Approximately 2,200 cubic yards of soil would be off-hauled over the course of project construction. The maximum depth of excavation for the project is up to 400 feet for the proposed geothermal system; no dewatering during construction of the project would be required.

8. Surrounding Land Uses and Setting:

Surrounding land uses include residential neighborhoods to the west, commercial buildings to the north, commercial buildings to the east across Brentwood Boulevard, and a grassy agricultural field to the south.

9. Determination:

An Initial Study for the proposed project identified potentially significant impacts in the environmental areas of aesthetics, air quality, biological resources, cultural resources, geology/soils, hazards and hazardous materials, noise, and tribal cultural resources.

Environmental analysis determined that measures were available to mitigate potential adverse impacts to less than significant levels. As a result, a Mitigated Negative Declaration (MND) has been prepared pursuant to Public Resources Code Section 21080(c), 21064.5, and Article 6 of the California Environmental Quality Act (CEQA) Guidelines.

Pursuant to the requirements of CEQA (CEQA Guidelines Section 15071) the MND describes the proposed project; identifies, analyzes, and evaluates the potential significant environmental impacts which may result from the proposed project; and identifies measures to mitigate adverse environmental impacts. Mitigations identified in this document designed for the proposed project will ensure that the project will not cause a significant impact on the environment.

Prior to adoption of a Mitigated Negative Declaration, the County will be accepting comments on the Initial Study and Draft Mitigated Negative Declaration during a 20-day public comment period.

The initial study/draft mitigated negative declaration may be reviewed at the Contra Costa County Public Works Department, 255 Glacier Drive, Martinez, during normal business hours, or viewed online at the following link: https://www.contracosta.ca.gov/4841/CEQA-Notifications. All documents referenced in the reference index can be provided upon request.

Public Comment Period – The period for accepting comments on the adequacy of the environmental document will begin Monday, February 2, 2026, and extend to 5:00 P.M., Monday, February 23, 2026. Any comments should be submitted in writing to the following:

Shravan Sundaram
Contra Costa County Public Works Department
255 Glacier Drive
Martinez, CA 94553
[email protected]
The proposed Mitigated Negative Declaration will be considered for adoption at a meeting of the County Board of Supervisors. The hearing date before the County Board of Supervisors has not yet been scheduled. To confirm the Board date, please contact Shravan Sundaram at [email protected] or directly at (925) 313-2366.

Sincerely,
Syd Sotoodeh
Senior Planner
Department of Conservation & Development
attch: Project Location Map (Figure 1)
Conceptual Site Plan (Figure 2)
Conceptual Building Heights (Figure 3)
cc: County Clerk’s Office (2 copies)
Adjacent Occupants and Property Owners

North Canary Creek Way
Goose Creek Avenue
Bear Creek Drive
Elk Creek Drive
Brush Creek Drive
Wooley Creek Way
Stratford
East Sand Creek Road
Stratford Court
Havenwood Avenue
Bamboo Drive
Central Boulevard
2nd Street
Pacifica Drive
Bella Drive
Brentwood Boulevard
Berry Lane
O'Hara
Avenue
Lynn Drive
Curtis Drive
E
Broderick Drive
llen Lane
Country Court
Sand Creek Road
Washington Drive
Technology Way
Je
erson Drive
Caper Drive
Caenne Drive
Marsh Creek Trail
Gracie Lane
Lone Oak Road
Sycamore Avenue
Woodfield Lane
Barbara Street
Tricia Street Spruce Street
Village Drive
W ni dsor Way
Susan Street
Marsh Creek

CONTRA COSTA COUNTY, CALIFORNIA
Los Angeles
Basemap Source:
© MapTiler and © OpenStreetMap
4 4
680
Concord
Antioch Pittsburg
Walnut
Creek
Oakley
Grizzly
Bay
Brentwood
Project Location
0 500 1,000
feet
Figure 1
Project Location
East County Service Center Project
Project Location
Graphics … 104857 Co Contra Costa East County (04-21-2025) Brentwood
•
N
A

Source: Perkins & Will 2025
Graphics … 104857 Co Contra Costa East County (12-10-2025) Figure 2
Conceptual Site Plan
East County Service Center Project
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Note: Image is conceptual until after project approval. The proposed building would be approximately 58 feet high, including the mechanical penthouse and mechanical roof equipment.

Source: Perkins & Will 2025
Technology Way
Graphics … 104857 Co Contra Costa East County (1-6-2025) Figure 3
Conceptual Building Heights
East County Service Center Project
Aerial View Looking Southeast

INITIAL STUDY/MITIGATED NEGATIVE DECLARATION

EAST COUNTY SERVICE CENTER
COUNTY FILE NO. CP#25-39
COUNTY PROJECT NO. WH429A
P REPARED FOR :

Contra Costa County Public Works Department
Environmental Services Division
255 Glacier Drive
Martinez, CA 94553
Contact: Shravan Sundaram
(925) 812-7702
P REPARED BY :

ICF
595 Market Street, Suite 950
San Francisco, CA 94105
Contact: Jessica Viramontes
(415) 677-7108
February 2026

ICF. 2026. Initial Study/Mitigated Negative Declaration, East County Service Center. February. (ICF 104857.0.002) San Francisco, CA. Prepared for Contra Costa County Public Works Department. Martinez, CA.

East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration i February 2026 Contents
Tables .................................................................................................................................................. iv Figures ................................................................................................................................................... v Acronyms and Abbreviations ................................................................................................................ vi Chapter 1 CEQA Environmental Checklist Form................................................................................ 1-1 Environmental Factors Potentially Affected ..................................................................................... 1-11 Environmental Determination........................................................................................................... 1-11 Chapter 2 Environmental Checklist.................................................................................................. 2-1

2.1 Aesthetics............................................................................................................................... 2-1

2.1.1 Discussion ........................................................................................................................ 2-1

2.1.2 Sources of Information .................................................................................................... 2-3

2.2 Agriculture and Forestry Resources....................................................................................... 2-4

2.2.1 Discussion ........................................................................................................................ 2-4

2.2.2 Sources of Information .................................................................................................... 2-5

2.3 Air Quality............................................................................................................................... 2-5

2.3.1 Discussion ........................................................................................................................ 2-5

2.3.2 Sources of Information .................................................................................................. 2-18

2.4 Biological Resources............................................................................................................. 2-19

2.4.1 Discussion ...................................................................................................................... 2-19

2.4.2 Sources of Information .................................................................................................. 2-26

2.5 Cultural Resources................................................................................................................ 2-27

2.5.1 Discussion ...................................................................................................................... 2-27

2.5.2 Sources of Information .................................................................................................. 2-32

2.6 Energy................................................................................................................................... 2-32

2.6.1 Discussion ...................................................................................................................... 2-32

2.6.2 Sources of Information .................................................................................................. 2-33

2.7 Geology/Soils........................................................................................................................ 2-33

2.7.1 Discussion ...................................................................................................................... 2-34

2.7.2 Sources of Information .................................................................................................. 2-37

2.8 Greenhouse Gas Emissions .................................................................................................. 2-37

2.8.1 Discussion ...................................................................................................................... 2-37

2.8.2 Sources of Information .................................................................................................. 2-49

2.9 Hazards and Hazardous Materials........................................................................................ 2-51

2.9.1 Discussion ...................................................................................................................... 2-51

2.9.2 Sources of Information .................................................................................................. 2-57

Contra Costa County Public Works Department Contents
East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration ii February 2026

2.10 Hydrology and Water Quality............................................................................................... 2-57

2.10.1 Discussion .................................................................................................................... 2-58

2.10.2 Sources of Information................................................................................................ 2-61

2.11 Land Use and Planning ......................................................................................................... 2-62

2.11.1 Discussion .................................................................................................................... 2-62

2.11.2 Sources of Information................................................................................................ 2-63

2.12 Mineral Resources................................................................................................................ 2-63

2.12.1 Discussion .................................................................................................................... 2-63

2.12.2 Sources of Information................................................................................................ 2-64

2.13 Noise..................................................................................................................................... 2-64

2.13.1 Discussion .................................................................................................................... 2-64

2.13.2 Sources of Information .............................................................................................. 2-81

2.14 Population and Housing ....................................................................................................... 2-81

2.14.1 Discussion .................................................................................................................... 2-82

2.14.2 Sources of Information................................................................................................ 2-82

2.15 Public Services...................................................................................................................... 2-83

2.15.1 Discussion .................................................................................................................... 2-83

2.15.2 Sources of Information................................................................................................. 2-85

2.16 Recreation............................................................................................................................. 2-85

2.16.1 Discussion .................................................................................................................... 2-85

2.17 Transportation...................................................................................................................... 2-86

2.17.1 Discussion .................................................................................................................... 2-86

2.17.2 Sources of Information................................................................................................. 2-89

2.18 Tribal Cultural Resources...................................................................................................... 2-90

2.18.1 Discussion .................................................................................................................... 2-90

2.18.2 Sources of Information................................................................................................ 2-93

2.19 Utilities and Service Systems................................................................................................ 2-93

2.19.1 Discussion .................................................................................................................... 2-93

2.19.2 Sources of Information................................................................................................ 2-97

2.20 Wildfire................................................................................................................................. 2-97

2.20.1 Discussion .................................................................................................................... 2-98

2.20.2 Sources of Information................................................................................................ 2-98

2.21 Mandatory Findings of Significance ..................................................................................... 2-99

2.21.1 Discussion .................................................................................................................... 2-99

2.21.2 Sources of Information.............................................................................................. 2-101 Chapter 3 List of Preparers.............................................................................................................. 3-1

Contra Costa County Public Works Department Contents
East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration iii February 2026

3.1 Contra Costa County Department of Conservation and Development (Lead Agency)................................................................................................................................... 3-1

3.2 Contra Costa County Public Works Department (Project Sponsor)....................................... 3-1

3.3 ICF (Environmental Consultant) ............................................................................................. 3-1

3.4 Cogstone (Cultural and Tribal Cultural Resources) ................................................................ 3-2 Attachment A Air Quality Modeling Data
Attachment B Assessment for Special-Status Species Not Covered by the East Contra Costa County Habitat Conservation Plan/Natural Community Conservation Plan and the Application Form and Planning Survey Report to Comply with and Receive Permit Coverage under Compliance with the East Contra Costa County Habitat Conservation Plan and Natural Community Conservation Plan
Attachment C Soil Investigation Report, Phase I Environmental Site Assessment, Phase II Environmental Site Assessment, and Peer Review of ACC Letter Regarding Management of Pesticide-Containing Soils
Attachment D Noise and Vibration Modeling Data
Attachment E Traffic Impact Study
Attachment F Mitigation Monitoring and Reporting Program for the Draft IS/MND

Contra Costa County Public Works Department Contents
East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration iv February 2026 Tables
Table 1-1: Proposed Project Overview ...................................................................................................... 1-2 Table 1-2: Potential Permits and Approvals ............................................................................................ 1-10 Table 2-1. Federal and State Attainment Status for the Contra Costa County Portion of the San Francisco Bay Area Air Basin .................................................................................................. 2-6 Table 2-2. Average Daily Criteria Pollutant Emissions from Project Construction (pounds per day) ............................................................................................................................................. 2-10 Table 2-3. Average Daily Operational Criteria Pollutant Emissions (pounds per day)............................. 2-12 Table 2-4. Estimated Unmitigated Project-Level Health Risk Results from Construction ....................... 2-14 Table 2-5. Estimated Mitigated Project-Level Health Risk Results from Construction............................ 2-14 Table 2-6. Cumulative Mitigated Health Risk Results.............................................................................. 2-16 Table 2-7. Air District Greenhouse Gas Thresholds for Land Use Projects.............................................. 2-40 Table 2-8. Operational Greenhouse Gas Emissions by Emissions Source for 2027................................. 2-44 Table 2-9. Project Consistency with the County’s 2024 CAAP Climate Action Strategies....................... 2-44 Table 2-10. Project Consistency with CARB 2022 Scoping Plan Key Project Attributes.......................... 2-48 Table 2-11. Summary of Noise Measurements ....................................................................................... 2-65 Table 2-12. Applicable City of Brentwood Exterior Noise Standards ...................................................... 2-72 Table 2-13. Comparison of Ambient and Ambient-with-Haul-Truck Noise Levels.................................. 2-74 Table 2-14. Predicted Rooftop Equipment Noise Levels at the Nearest Sensitive Receptors................. 2-76 Table 2-15. Predicted Ground-Level Equipment Noise Levels at the Nearest Sensitive Receptors.................................................................................................................................... 2-77 Table 2-16. 2018 No-Project and 2018 with-Project Noise Levels .......................................................... 2-79 Table 2-17. 2018 No Project and 2040 With Project Traffic Noise Levels............................................. 2-100

Contra Costa County Public Works Department Contents
East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration v February 2026 Figures
Figure 1. Project Location .......................................................................................................................... 1-4 Figure 2. Conceptual Site Plan ................................................................................................................... 1-6 Figure 3. Conceptual Building Heights....................................................................................................... 1-8 Figure 4. Noise Measurement Locations................................................................................................. 2-66 Figure 5. Maximum Allowable Noise Exposure by Use............................................................................ 2-68 Figure 6. City General Plan Land Use Compatibility Matrix for Community Noise Environment............ 2-70

Contra Costa County Public Works Department Contents
East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration vi February 2026 Acronyms and Abbreviations
Acronym Definition
AB Assembly Bill
ABAG Association of Bay Area Governments
Air District Bay Area Air District
Air District CEQA Guidelines California Environmental Quality Act Air Quality Guidelines AM morning
ARPA Archaeological Resources Protection Act
ATCM Airborne Toxic Control Measure
BART Bay Area Rapid Transit
BBSP Brentwood Boulevard Specific Plan
BERD Built-Environment Resource Directory
bgs below ground surface
BMPs best management practices
BP Business Park
CAAP Climate Action and Adaptation Plan
CAAQS California Ambient Air Quality Standards
CAL FIRE California Department of Forestry and Fire Protection CalEEMod California Emissions Estimator Model
CalEnviroScreen California Communities Environmental Health Screening Tool CalEPA California Environmental Protection Agency
CALGreen California Green Building Standards Code
Caltrans California Department of Transportation
CAPCOA California Air Pollution Control Officers Association CARB California Air Resources Board
CCTA Contra Costa Transportation Authority
CDFW California Department of Fish and Wildlife
CEQA California Environmental Quality Act
CESA California Endangered Species Act
CH4 methane
CHL California Historical Landmarks
CHRIS California Historical Resources Information System City City of Brentwood
City General Plan City of Brentwood General Plan
CMP Congestion Management Program
CNDDB California Natural Diversity Database
CNPS California Native Plant Society
CO carbon monoxide
CO2 carbon dioxide

Contra Costa County Public Works Department Contents
East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration vii February 2026 Acronym Definition
CO₂e carbon dioxide equivalent
County Contra Costa County
County General Plan Contra Costa County 2045 General Plan CPHI California Points of Historical Interest
CPTs cone penetration tests
CRHR California Register of Historical Resources
CVLN Confederated Villages of Lisjan Nation
dB decibel
dBA A-weighted decibel scale
DPM diesel particulate matter
DPR California Department of Parks and Recreation
DTSC Department of Toxic Substances Control
EPA Environmental Protection Agency
ESA Environmental Site Assessment
ESLs Environmental Screening Levels
EV electric vehicle
EVSE EV supply equipment
FEMA Federal Emergency Management Agency
FHWA Federal Highway Administration
FTA Federal Transit Administration
FTA Manual Transit Noise and Vibration Impact Assessment Manual GHG greenhouse gas
GIS Geographic information system
GSP groundwater sustainability plan
HCP habitat conservation plan
HFCs hydroflourocarbons
HRA health risk assessment
HVAC heating, ventilation, and air-conditioning
IPaC Information for Planning and Consultation
Ldn day/night level
LEED Leadership in Energy and Environmental Design
Leq equivalent sound level
Lmax maximum sound level
LRA Local Responsibility Area
MBTA Migratory Bird Treaty Act
mgd million gallons per day
MLD Most Likely Descendant
MRP San Francisco Bay Region Municipal Regional Stormwater National Pollutant Discharge Elimination System Permit
MT metric tons

Contra Costa County Public Works Department Contents
East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration viii February 2026 Acronym Definition
MTC Metropolitan Transportation Commission
N2O nitrous oxide
NAAQS National Ambient Air Quality Standards
NAHC Native American Heritage Commission
NCCP natural community conservation plan
NHPA National Historic Preservation Act
NO2 nitrogen dioxide
NOX nitrogen oxide
NPDES The National Pollutant Discharge Elimination System NRHP National Register of Historic Places
NWIC Northwest Information Center
O3 ozone
OCPs organochlorine pesticides
OEHHA Office of Environmental Health Hazard Assessment
PD Planned Development
PG&E Pacific Gas & Electric
PM evening
PM10 particulate matter no more than 10 microns in diameter PM2.5 particulate matter no more than 2.5 microns in diameter PPD pounds of disposal per person per day
PPV peak particle velocity
proposed project East County Service Center
RCRA Resource Conservation and Recovery Act
RECs recognized environmental conditions
rms root-mean-square
ROG reactive organic gas
RTP regional transportation plan
RTPCs Regional Transportation Planning Committees
SB Senate Bill
SCS sustainable communities strategy
SF6 sulfur hexafluoride
SFBAAB San Francisco Bay Area Air Basin
SLF Sacred Lands File
SMP soil management plan
SO2 sulfur dioxide
SR State Route
SWCP Stormwater Control Plan
SWPPP Stormwater Pollution Prevention Plan
SWRCB State Water Resources Control Board
TACs toxic air contaminants

Contra Costa County Public Works Department Contents
East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration ix February 2026 Acronym Definition
TAZ Travel Analysis Zone
TNM Traffic Noise Model
U.S.C. United States Code
USFWS U.S. Fish and Wildlife Service
VdB velocity decibels
VMT vehicle miles traveled
VOCs volatile organic compounds
WEAP Worker Environmental Awareness Program
ZEV zero-emission vehicle

East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 1-1 February 2026 Chapter 1
CEQA Environmental Checklist Form

1. Project Title:

East County Service Center
County File No. CP#25-39, County Project No. WH429A

2. Lead Agency Contact:

Syd Sotoodeh, Senior Planner, (925) 655-2877
[email protected]
Contra Costa County Department of Conservation and Development 30 Muir Road
Martinez, CA 94553

3. Contact Person and Phone Number:

Shravan Sundaram, Environmental Analyst II, (925) 812-7702 [email protected]
Contra Costa County Public Works Department, Environmental Services Division 255 Glacier Drive
Martinez, CA 94553

4. Project Sponsor’s Name and Address:

Contra Costa County Public Works Department
255 Glacier Drive
Martinez CA 94553

5. General Plan Designation:

The project site is owned by Contra Costa County (County) and located in the city of Brentwood.

Thus, there is no Envision Contra Costa County 2045 General Plan (County General Plan) designation for the project site. The proposed project is not required to comply with the City of Brentwood General Plan (City General Plan) designations for the project site; the designations are provided for informational purposes only. According to the City General Plan, the project site has Business Park (BP) and Brentwood Boulevard Specific Plan (BBSP) general plan designations.

6. Zoning Designation:

The project site is owned by the County and located in the city of Brentwood. Thus, there is no County zoning designation for the project site. The proposed project is not required to comply with the Brentwood Municipal Code zoning designations for the project site; the designations are provided for informational purposes only. According to the Brentwood Municipal Code, the project site has Planned Development (PD-42) and BBSP zoning designations.

7. Project Location:

The approximately 7.86-acre project site is located along Technology Way south of Sand Creek Road, between Business Circle Drive and Brentwood Boulevard, in Brentwood (Assessor’s Parcel Numbers [APNs] 016-410-008, 016-410-009, 016-410-010, 016-410-011, 016-410-012, 016-410-013, and 016-120-024).

Contra Costa County Public Works Department CEQA Environmental Checklist Form East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 1-2 February 2026

8. Description of Project:

The County proposes construction of a new East County Service Center (proposed project) at Technology Way and Brentwood Boulevard in the city of Brentwood, East Contra Costa County (see Figure 1). The project site is a flat, grassy undeveloped lot with no trees, buildings, or utilities. A gravel staging area exists in the northwest portion of the project site.

The new facility would house multiple County departments and provide a centralized service center for residents of East Contra Costa County, which is one of the fastest-growing regions within the county. The new three-story building would provide approximately 120,000 gross square feet of usable space and have a maximum height of approximately 58 feet, including the mechanical penthouse and mechanical roof equipment (see Figures 2 and 3). The building would include a lobby area, administrative offices for approximately 10 County departments, conference rooms, building support rooms, and other amenities. For the public, there would be one main entrance to the lobby area and two ancillary entrances on the side of the building.

Similarly, for staff, there would be one main entrance to the lobby area and two ancillary entrances on the side of the building. In addition, there would be 16 restrooms, including 6 for the public and 10 for staff use. Two public elevators, two staff-only elevators, and three stair towers (one with roof access) would provide access to the upper floors. One open staircase would lead from the main lobby to the second-level lobby area. The on-site staff would have access to the roof terraces on the second and third levels; the terraces would have a pedestal paver system. Table 1-1 provides an overview of the proposed project.

Table 1-1: Proposed Project Overview
Feature Overview
Project Site 7.86 acres at Technology Way and Brentwood Boulevard in the city of Brentwood
Building Gross
Square Footage
120,000 gross square feet
Building Height 3 stories
Approximately 58 feet high, including the mechanical penthouse and mechanical roof equipment
Employees Approximately 441 County staff members
Vehicular Parking 409 parking stalls (286 for staff, 79 for visitors, and 44 for fleet vehicles) Bicycle Parking 58 spaces (22 long-term spaces and 36 short-term spaces) Sustainability Leadership in Energy and Environmental Design (LEED) Silver rating, at a minimum
The building structure would be mass timber, and exterior siding would be glass-fiber reinforced concrete. A curtain wall system and cast-in-place concrete with metal fin accents for consistency with other modern County buildings would also be used.

The proposed project would be fully electric. The proposed project would include a rooftop photovoltaic system to supply on-site renewable energy. The photovoltaic system would be connected to an approximately 688-kilowatt battery back-up system. The battery back-up system would be located in the vehicle parking area south of the proposed building. In addition, the proposed building would include a hybrid heating, ventilation, and air-conditioning (HVAC) system consisting of both a geothermal system and a heat pump. The geothermal system would

Contra Costa County Public Works Department CEQA Environmental Checklist Form East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 1-3 February 2026 include approximately 60 wells down to a maximum of 400 feet. The pumphouse would be located west of the proposed building and the wells would be located throughout the vehicle parking areas. The heat pump would be located on the roof of the proposed building. Building systems would be designed by the Architect on Record/Engineer on Record. The proposed project would achieve, at a minimum, a Leadership in Energy and Environmental Design (LEED) Silver rating.

The project site would be developed with stormwater treatment basins, pedestrian walkways, and a public plaza along the north façade that would wrap around the corner entry. These treatment features are expected to decrease the rate and volume of stormwater runoff. A trellis or gazebo would be provided for outdoor functions. A covered area outside the conference rooms would be located at the east end of the building. There would be a 180-foot passenger drop-off zone with permeable pavers running parallel to the public plaza on the north side of the building adjacent to a secure child play area. An approximately 8-foot-tall fence would be installed along the perimeter of the staff and fleet vehicle parking areas and at the east end of the building.

Regarding site improvements, the proposed project would include approximately 43,000 square feet of concrete paving, 10,000 square feet of sidewalk, and 1,200 linear feet of curbing.

Regarding roadways and parking, the proposed project would include approximately 160,000 square feet of asphalt concrete paving, 11,000 linear feet of concrete curbing, and 500 square feet of permeable pavers. A planned plaza and right-of-way planting would require approximately 42,000 square feet of paving. Landscaping is planned for approximately 28,000 square feet of the project site. New plantings would include a mix of native, drought-tolerant plants. There are currently no trees on the project site; thus, the proposed project would not require the removal of any trees.

North Canary Creek Way
Goose Creek Avenue
Bear Creek Drive
Elk Creek Drive
Brush Creek Drive
Wooley Creek Way
Stratford
East Sand Creek Road
Stratford Court
Havenwood Avenue
Bamboo Drive
Central Boulevard
2nd Street
Pacifica Drive
Bella Drive
Brentwood Boulevard
Berry Lane
O'Hara
Avenue
Lynn Drive
Curtis Drive
E
Broderick Drive
llen Lane
Country Court
Sand Creek Road
Washington Drive
Technology Way
Je
erson Drive
Caper Drive
Caenne Drive
Marsh Creek Trail
Gracie Lane
Lone Oak Road
Sycamore Avenue
Woodfield Lane
Barbara Street
Tricia Street Spruce Street
Village Drive
W ni dsor Way
Susan Street
Marsh Creek

CONTRA COSTA COUNTY, CALIFORNIA
Los Angeles
Basemap Source:
© MapTiler and © OpenStreetMap
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680
Concord
Antioch Pittsburg
Walnut
Creek
Oakley
Grizzly
Bay
Brentwood
Project Location
0 500 1,000
feet
Figure 1
Project Location
East County Service Center Project
Project Location
Graphics … 104857 Co Contra Costa East County (04-21-2025) Brentwood
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Contra Costa County Public Works Department CEQA Environmental Checklist Form East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 1-5 February 2026

PAGE LEFT BLANK INTENTIONALLY

Source: Perkins & Will 2025
Graphics … 104857 Co Contra Costa East County (12-10-2025) Figure 2
Conceptual Site Plan
East County Service Center Project
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Contra Costa County Public Works Department CEQA Environmental Checklist Form East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 1-7 February 2026

PAGE LEFT BLANK INTENTIONALLY

Note: Image is conceptual until after project approval. The proposed building would be approximately 58 feet high, including the mechanical penthouse and mechanical roof equipment.

Source: Perkins & Will 2025
Technology Way
Graphics … 104857 Co Contra Costa East County (1-6-2025) Figure 3
Conceptual Building Heights
East County Service Center Project
Aerial View Looking Southeast

Contra Costa County Public Works Department CEQA Environmental Checklist Form East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 1-9 February 2026 Access and Parking
The East County Service Center would be accessed by the public from Technology Way, with staff-only gated entrances on Business Center Drive and Brentwood Boulevard. Access points would be constructed to comply with City of Brentwood (City) standards for the portions within the public right-of-way. The two public parking lots would be accessed from Technology Way, while staff-only parking would be accessed from Business Center Drive and Brentwood Boulevard via automated gates.

The proposed project would include approximately 409 parking stalls, with 286 stalls for employees, 79 stalls for visitors, and 44 stalls for fleet vehicles (see Figure 2 and Table 1-1). The project would include 108 EV-capable spaces, with 82 Type 2 electric vehicle (EV) chargers and 4 DC fast charging stations . The proposed project would also include 17 covered bike parking spaces for staff members and four spaces for the public. In addition, the proposed project would include the following modifications to the circulation system:
• 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., access points, modifications to the circulation system, utility connections, etc.) within the public right-of-way would be constructed to comply with City standards.

Occupancy
The proposed project would result in approximately 441 County employees working at the project site, including approximately 150 relocated employees from other County facilities.

Construction Schedule and Construction Activities
Project construction is anticipated to begin in early 2026 and be completed by the end of 2027, a period of approximately 20 months. The phases of project construction include:
• Phase 1: Site mobilization and site preparation, which would take approximately 1 month. • Phase 2: Rough grading, site utilities, and geothermal work, which would take approximately 10 weeks.
• Phase 3: Foundations, which would take approximately 6 weeks. • Phase 4: Construction of the building, which would take approximately 15 months. • Phase 5: Paving and landscaping, which would take approximately 1 month. • Phase 6: Application of architectural coatings, which would take approximately 1 month.

Contra Costa County Public Works Department CEQA Environmental Checklist Form East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 1-10 February 2026 Construction grading is anticipated to affect the entire project site (i.e., approximately 7.86 acres, or 340,000 square feet). Approximately 2,200 cubic yards of soil would be off-hauled over the course of project construction. The maximum depth of excavation for the project is up to 400 feet for the proposed geothermal system; no dewatering during construction of the project would be required.

9. Surrounding Land Uses and Setting:

Surrounding land uses include residential neighborhoods to the west, commercial buildings to the north, commercial buildings to the east across Brentwood Boulevard, and a grassy agricultural field to the south.

10. Other Agencies Whose Approval Is Required:

Although the County is the California Environmental Quality Act (CEQA) lead agency for the project, other agencies also have discretionary authority related to the project, including approvals or responsibilities. Table 1-2 provides a list of the agencies and potential permits and approvals that may be required.

Table 1-2: Potential Permits and Approvals
Agency Permits/Approvals
Contra Costa County Department of Conservation and
Development, Building Inspection Division
Grading and Building Permits
East Contra Costa County Habitat Conservancy Development Fees Contra Costa County Fire Protection District Fire Code Compliance City of Brentwood Encroachment Permit

11. Have California Native American tribes traditionally and culturally affiliated with the project area requested consultation pursuant to Public Resources Code Section 21080.3.1? If so, is there a plan for consultation that includes, for example, the determination of significance of impacts on tribal cultural resources, procedures regarding confidentiality, etc.?
Yes, tribes that previously requested to be notified of projects within Contra Costa County under Assembly Bill (AB) 52 include Wilton Rancheria and the Confederated Villages of Lisjan Nation (CVLN). The County conducted 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 and avoidance, mitigation, and monitoring measures. Measures were agreed upon, and consultation was concluded on September 10, 2025.

Contra Costa County Public Works Department CEQA Environmental Checklist Form East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 1-11 February 2026 Environmental Factors Potentially Affected
The environmental factors checked below could be affected by this project, with at least one impact that would be a “potentially significant impact,” as indicated by the checklists on the pages below.

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

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

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

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

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

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

Syd Sotoodeh, Senior Planner
Contra Costa County Department of Conservation and Development Date
January 26, 2026
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East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-1 February 2026 Chapter 2
Environmental Checklist

2.1 Aesthetics
Potentially
Significant
Impact
Less than
Significant with
Mitigation
Incorporated
Less-thanSignificant
Impact No Impact
Except as provided in Public Resources Code Section 2.1099, would the project:
a) Have a substantial adverse effect on a scenic vista? b) Substantially damage scenic resources, including, but not limited to, trees. rock outcroppings. and historic buildings within a state scenic highway?
c) In non-urbanized areas. substantially degrade the existing visual character or quality of public views of the site and its surroundings? (Public views are those that are experienced from publicly accessible vantage points). If the project is in an urbanized area, would the project conflict with applicable zoning and other regulations governing scenic quality?
d) Create a new source or substantial light or glare that would adversely affect daytime or nighttime views in the area?

2.1.1 Discussion
a) Would the project have a substantial adverse effect on a scenic vista? According to the City General Plan and the County General Plan (City of Brentwood 2014; Contra Costa County 2024), the County has one main scenic resource in the project vicinity in addition to localized scenic features such as hills, ridgelines, and open space areas. The main scenic resource, Mount Diablo, is approximately 12.5 miles southwest of the project site and is visible from the project site (Google Earth 2024). The proposed project could partially obstruct views of Mount Diablo from Brentwood Boulevard. However, the project would not have a substantial adverse effect on the scenic vista, considering the developed nature of the existing surroundings and the relative height of the proposed building (approximately 58 feet, including the mechanical penthouse and mechanical roof equipment). The approximately 58-foot-tall building would be of a height similar to that of many of the trees surrounding the project site, which would reduce the obstructive effect of the proposed building. In addition, the viewers who would be most affected would be worker receptors; such viewers have lower viewer sensitivity than residential or recreational receptors.

Therefore, the project would have a less-than-significant impact. b) Would the project substantially damage scenic resources, including, but not limited to, trees, rock outcroppings, and historic buildings within a state scenic highway? The project site is not within a state scenic highway (California Department of Transportation [Caltrans] 2018). The County General Plan supports preservation and enhancement of natural and human-made features that contribute to the scenic quality of the landscape and viewshed along designated scenic routes and discourages projects that interfere with public views of those features (County 2024). State Route (SR) 4, which is approximately 2.5 miles west of the project site, is □
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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 2-2 February 2026 identified as a County scenic route in the County General Plan. However, the project site is in an urbanized area east of SR 4 and not within the SR 4 corridor or visible from SR 4. There are no historic buildings, rock outcroppings, or other potentially scenic resources within the project site.

Furthermore, there are no trees on the project site; thus, the proposed project would not require the removal of trees and would not affect the scenic quality of the area. Therefore, the project would have no impact.
c) In non-urbanized areas, would the project substantially degrade the existing visual character or quality of public views of the site and its surroundings? (Public views are those that are experienced from publicly accessible vantage points). If the project is in an urbanized area, would the project conflict with applicable zoning and other regulations governing scenic quality? 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 project site is owned by the County and located in the city of Brentwood. Thus, there is no County General Plan designation for the project site. Because the project site is owned by the County, the proposed project is not required to comply with the 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. The City General Plan land use designation for the project site is Business Park (BP), which allows integrated business and research parks, large corporate establishments, professional and administrative office centers, and light industrial complexes.

Complementary commercial activities and limited residential uses may also be allowed. The City of Brentwood Code of Ordinances designates the project site as Planned Development (PD-42), Subarea F, which allows a variety of commercial uses (e.g., general retail; office uses; medical and dental offices and laboratories; nurseries and day-care centers; public and quasi-public uses, such as trade schools; and industrial and service uses with conditional use permits) (City of Brentwood 2025). The project, which involves a centralized service center that would include administrative uses, falls into the Subarea F category of allowed uses. The maximum building height in Subarea F is three stories, or 40 feet. Structures greater than 40 feet, like the proposed project, may be permitted with conditional use permit approval, however the County is not required to comply nor obtain this permit. The proposed building would have a maximum height of approximately 58 feet, including the mechanical penthouse and mechanical roof equipment. The project would not conflict with applicable zoning or other regulations governing scenic quality because development of the service center would not remove elements that define the area or introduce buildings, structures, or other features that would not be compatible with the character of the area. Therefore, the project would have a less-than-significant impact.
d) Would the project create a new source or substantial light or glare that would adversely affect daytime or nighttime views in the area?
Construction is anticipated to occur during daylight hours, although temporary nighttime lighting during construction could be present for safety and security purposes. In addition, if unforeseen circumstances necessitate night work that requires nighttime lighting, it would be temporary and require approval by the County construction management firm, which will be available to address any concerns. Therefore, the project would have a less-than-significant impact related to construction.

During operation, the proposed project would introduce new sources of interior and exterior lighting, including security lighting in parking areas, that currently do not exist on the project site.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-3 February 2026 Although operations would be limited to weekday daytime shifts (7:00 a.m.–5:30 p.m.), nighttime lighting would be present for safety and security purposes. The project site is located in an urbanized area with existing sources of nighttime lights, including streetlights and headlights from vehicles and existing interior lighting from surrounding residential and commercial uses. In addition, the project would incorporate landscaping, including trees around the perimeter of the site, which would diminish additional nighttime lighting perceived outside of the project site.

However, the exterior lighting and security lighting for the parking lot would create new onsite light sources that could shine on adjacent properties and provide undesirable ambient light, which could result in a potential adverse impact due to new light on neighboring properties, which could be significant. In addition, glare could be caused by light reflected from pavement, vehicles, and building materials, such as reflective glass and polished surfaces within the project site, which could result in a potential adverse impact due to new glare on neighboring properties, a potentially significant impact. Implementation of Mitigation Measure AES-1 and Mitigation Measure AES-2, below, would reduce the spillover of lighting and glare from within the project site to adjacent properties. Therefore, the project would have a less-than-significant impact with mitigation incorporated.

Mitigation Measures AES-1: Shielded Lighting Fixtures
The final lighting plan shall include lighting with decorative lighting fixtures that are shielded to face down and screened away from adjacent properties.

Mitigation Measure AES-2: Glazing Window Treatments
The final design plan shall include glazing window treatments to minimize the intensity of daylight glare.

2.1.2 Sources of Information
California Department of Transportation. 2018. California State Scenic Highway System Map.

Available: https://caltrans.maps.arcgis.com/apps/webappviewer/index.html?id=465dfd3d807 c46cc8e8057116f1aacaa.

City of Brentwood. 2014. City of Brentwood General Plan. Adopted July 22, 2014. Available:
https://www.brentwoodca.gov/home/showpublisheddocument/2900/63870028552070000.

City of Brentwood. 2025. City of Brentwood Code of Ordinances. Title 17, Article VIII, Planned Development Zone. Chapter 17.492 PD-42. Available: https://ecode360.com/43622536# 43622596.

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.

Google Earth. 2024. Directions from Technology Way to Mount Diablo.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-4 February 2026

2.2 Agriculture and Forestry Resources
Potentially
Significant
Impact
Less than
Significant with
Mitigation
Incorporated
Less-thanSignificant
Impact No Impact
Would the project:
a) Convert Prime Farmland, Unique Farmland, or Farmland of Statewide Importance (Farmland), as shown on maps
prepared pursuant to the Farmland Mapping and Monitoring Program of the California Resources Agency, to nonagricultural use? b) Conflict with existing zoning for agricultural use or a Williamson Act contract?
c) Conflict with existing zoning for, or cause rezoning of, forestland (as defined in Public Resources Code Section 12220[9]), timberland (as defined by Public Resources Code Section 4526), or timberland zoned for timberland production (as defined by Government Code Section 51104[9])?
d) Result in the loss of forestland or conversion of forestland to non-forest use?
e) Involve other changes in the existing environment that, due to their location or nature, could result in the conversion of Farmland to non-agricultural use or the conversion of
forestland to non-forest use?

2.2.1 Discussion
a) Would the project convert Prime Farmland, Unique Farmland, or Farmland of Statewide Importance (Farmland), as shown on maps prepared pursuant to the Farmland Mapping and Monitoring Program of the California Resources Agency, to non-agricultural use? According to the 2016 Contra Costa County Important Farmland Map, the project site is classified as “Urban and Built-Up Land” (California Department of Conservation 2018). As such, development of the project would not result in the conversion of Prime Farmland, Unique Farmland, or Farmland of Statewide Importance to a non-agricultural use. Therefore, the project would have no impact. b) Would the project conflict with existing zoning for agricultural use, or a Williamson Act contract? The project site is not zoned for agricultural use; therefore, the project would not conflict with existing zoning for agricultural use or a Williamson Act contract. Therefore, the project would have no impact.
c) Would the project conflict with existing zoning for, or cause rezoning of, forestland (as defined in Public Resources Code Section 12220[9]), timberland (as defined by Public Resources Code Section 4526). or timberland zoned for timberland production (as defined by Government Code Section 51104[9])? The project site is not zoned for forestland, timberland, or timberland production. Therefore, the project would have no impact.
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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 2-5 February 2026 d) Would the project result in the loss of forestland or conversion of forestland to non-forest use? The project site is not forestland and therefore would not result in the loss of forestland and/or conversion of forestland. Therefore, the project would have no impact. e) Would the project involve other changes in the existing environment that, due to their location or nature, could result in the conversion of Farmland to non-agricultural use or the conversion of forestland to non-forest use?
There is no nearby farmland or forestland. The project vicinity is developed primarily with residential and commercial uses; therefore, the project would not result in the conversion of farmland to non-agricultural use. Therefore, the project would have no impact.

2.2.2 Sources of Information
California Department of Conservation. 2018. Contra Costa County 2016 Important Farmland Mapping and Monitoring Program. Division of Land Resource Protection. Available:
https://www.conservation.ca.gov/dlrp/fmmp.

2.3 Air Quality
Potentially
Significant
Impact
Less than
Significant with
Mitigation
Incorporated
Less-thanSignificant
Impact No Impact
Would the project:
a) Conflict with or obstruct implementation of the applicable air quality plan?
b) Result in a cumulative considerable net increase in any criteria pollutant for which the project region is in nonattainment under an applicable federal or state ambient air quality standard?
c) Expose sensitive receptors to substantial pollutant
concentrations?
d) Result in other emissions (such as those leading to odors) adversely affecting a substantial number of people?

2.3.1 Discussion
Setting
The project site is in the city of Brentwood, which is in Contra Costa County and the San Francisco Bay Area Air Basin (SFBAAB). Concentrations of ozone (O3), carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), lead, and particulate matter (PM10 [particulate matter no more than 10 microns in diameter] and PM2.5 [particulate matter no more than 2.5 microns in diameter]) are commonly used indicators of ambient air quality conditions. These pollutants are known as criteria pollutants and regulated by the U.S. Environmental Protection Agency (EPA) and California Air Resources Board (CARB)through the National Ambient Air Quality Standards (NAAQS) and California Ambient Air Quality Standards (CAAQS), respectively. The NAAQS and CAAQS limit criteria pollutant concentrations to protect human health and prevent environmental and property damage.

ISi ISi
ISi ISi

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-6 February 2026 Regional Attainment Status
CARB and EPA maintain ambient air quality monitoring stations within California. Local monitoring data are used to designate areas as nonattainment, maintenance, attainment, or unclassified areas for ambient air quality standards. The four designations are defined below. Table 2-1 summarizes the attainment status of Contra Costa County.
• Nonattainment—assigned to areas where monitored pollutant concentrations consistently violate the standard in question
• Maintenance—assigned to areas where monitored pollutant concentrations exceeded the standard in question in the past but are no longer in violation of that standard • Attainment—assigned to areas where pollutant concentrations meet the standard in question over a designated period of time
• Unclassified—assigned to areas where data are insufficient for determining whether a pollutant is violating the standard in question.

Table 2-1. Federal and State Attainment Status for the Contra Costa County Portion of the San Francisco Bay Area Air Basin
Criteria Pollutant Federal Designation State Designation Ozone (O3 [8-hour standard]) Marginal nonattainment Nonattainment – Transitional Carbon monoxide (CO) Attainment Attainment
Particulate matter (PM10) Unclassified Nonattainment
Fine particulate matter (PM2.5) Moderate nonattainment (2006) Nonattainment Nitrogen dioxide (NO2) Attainment Attainment
Sulfur dioxide (SO2) Attainment Attainment
Lead Attainment Attainment
Sulfates (no federal standard) Attainment
Hydrogen sulfide (no federal standard) Unclassified
Visibility-reducing particles (no federal standard) Unclassified Sources: CARB 2023; EPA 2025.

Existing Toxic Air Contaminant Sources and Health Risks The Bay Area Air District (Air District) maintains an inventory, which is available online, of health risks associated with all permitted stationary sources within the SFBAAB (Air District 2024). Within 1,000 feet of the project site, there is one permitted facility: a gasoline dispensing facility, Brentwood Petroleum, at 7920 Brentwood Boulevard. Aside from stationary sources, emissions of toxic air contaminants (TACs) around the project site are also generated from mobile sources on roads and highways, such as SR 4, which is approximately 2.1 miles west of the project site, and diesel-powered locomotives on railroad tracks, which are approximately 0.4 mile southwest of the project site. Health risks associated with the nearby permitted stationary source, roads, and railways are considered in the analysis of the project’s cumulative health risks.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-7 February 2026 Environmental Burdens
The Office of Environmental Health Hazard Assessment (OEHHA) maintains the California Communities Environmental Health Screening Tool (CalEnviroScreen), which provides relative rankings of census tracts, based on 21 environmental, health, demographic, and socioeconomic indicators (e.g., O3 concentrations, groundwater threats, education levels). Scores are given on a scale of 0 to 100, with larger numbers representing areas with relatively high existing pollution burdens and population sensitivities. The proposed project is in Census Tract 6013303102, which has a CalEnviroScreen percentile score of 51. This score indicates that the census tract experiences more minor levels of pollution, as well as secondary effects, than the rest of the state (OEHHA 2023).

Because the census tract has a CalEnviroScreen score lower than 70 percent, it is not considered an overburdened community, per Air District guidance (Air District 2023).

Regulatory Setting
The Air District is responsible for ensuring that the NAAQS and CAAQS are met within the SFBAAB.

Specifically, the Air District manages air quality through a comprehensive program that includes long-term planning, regulations, and incentives for technical innovation, education, and community outreach. The Air District’s 2017 Clean Air Plan (Spare the Air, Cool the Climate) is the current air quality attainment plan for the SFBAAB. It provides an integrated strategy for reducing O3, particulate matter, TACs, and greenhouse gas (GHG) emissions in a manner that is consistent with federal and state air quality programs and regulations. Specifically, the Clean Air Plan:
• Describes the Air District plan for attaining all state and federal air quality standards and eliminating health risk disparities from exposure to air pollution among Bay Area communities; • Defines a vision for transitioning the region to the post‐carbon economy needed to achieve ambitious GHG reduction targets for 2030 and 2050;
• Provides a regional climate protection strategy that will put the Bay Area on a pathway to achieving GHG reduction targets; and
• Includes a wide range of control measures to decrease emissions of air pollutants that are harmful to Bay Area residents, such as particulate matter, O3, and TACs; reduce emissions of methane and other GHGs with high global warming potential that are potent climate pollutants for the near term; and decrease emissions of CO by reducing fossil fuel combustion.

In addition to air quality plans, the Air District also adopts rules and regulations to improve existing and future air quality. The proposed project may be subject to the Air District rules below. • Regulation 2, Rule 2 (New Source Review)—contains requirements for best available control technology and emission offsets
• Regulation 2, Rule 5 (New Source Review of Toxic Air Contaminants)—outlines guidance for evaluating TAC emissions and their potential health risks • Regulation 6, Rule 1 (Particulate Matter)—restricts emissions of particulate matter darker than a 1 on the Ringlemann Chart to less than 3 minutes in any 1 hour • Regulation 7 (Odorous Substances)—establishes general odor limitations for odorous substances and specific emission limitations for certain odorous compounds • Regulation 8, Rule 3 (Architectural Coatings)—limits the amount of reactive organic gas (ROG) in architectural coatings

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-8 February 2026 Air District California Environmental Quality Act Air Quality Guidelines In April 2023, the Air District published the most recent version of its California Environmental Quality Act Air Quality Guidelines (Air District CEQA Guidelines). The Air District CEQA Guidelines provide recommended procedures for evaluating potential air impacts during the environmental review process, consistent with CEQA requirements, and include recommended thresholds of significance, mitigation measures, and background air quality information. They also include recommended assessment methodologies for TACs and odors as well as best practices for centering environmental justice, health, and equity.
a) Would the project conflict with or obstruct implementation of the applicable air quality plan? As described under Regulatory Setting, the current air quality attainment plan for the SFBAAB is the Air District’s 2017 Clean Air Plan, which defines control strategies for reducing emissions and ambient concentrations of air pollutants; safeguards public health by reducing exposure to the air pollutants that pose the greatest health risks, with an emphasis on protecting the communities most heavily affected by air pollution; and reduces GHG emissions to protect the climate (Air District 2017). According to the Air District CEQA Guidelines, determination of 2017 Clean Air Plan consistency should consider the following for project-level analyses (Air District 2023):
• Does the project support the primary goals of the 2017 Clean Air Plan? • Does the project include all applicable control measures from the 2017 Clean Air Plan? • Does the project disrupt or hinder implementation of any 2017 Clean Air Plan control measures?
The project includes numerous components that would support the primary goals of the 2017 Clean Air Plan and regional attainment of the NAAQS and CAAQS. The project would be fully electric, thereby avoiding emissions from operational energy use compared to a similar development that uses natural gas. The all-electric design is possible because of the hybrid HVAC system, which comprises a geothermal system and a heat pump. The project would also provide EV charging parking. In addition, the project is expected to achieve, at a minimum, a LEED Silver rating.

Because the project site would be less than 0.25 mile from the Brentwood Boulevard and Sand Creek Road bus stop, which is served by Tri Delta Transit’s 300X Brentwood Park & Ride and the Antioch Bay Area Rapid Transit (BART) line, project employees would have the option of using transit instead of driving. This would promote transit use and be in line with the 2017 Clean Air Plan’s goal to reduce transportation-related emissions (Tri Delta Transit 2025). Overall, the project is expected to reduce driving distances for County employees and residents who would work at or visit the site, respectively. The addition of a new County services center means that people living in the eastern portion of Contra Costa County would not have to travel as far to work or receive services provided by the County. Although this effect has not been quantified, the expected result is that driving distances and, therefore, air pollution would be reduced.

Finally, as discussed under Impact b, emissions from both construction and operation would remain below the applicable Air District significance thresholds, which would help to reduce emissions and ambient concentrations of air pollutants in the SFBAAB. The project would therefore support the primary goals of the 2017 Clean Air Plan.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-9 February 2026 With respect to the project’s consistency with the control measures from the 2017 Clean Air Plan, most of the measures, such as those related to energy, buildings, water, stationary sources, and agriculture/natural and working lands, would not apply to the project because the implementation action required is not under the control of the project sponsor. For example, electric utilities or local governments would need to implement energy measures. In addition, other measures apply to land uses that are unrelated to the project, such as agricultural land uses.

As detailed above, the project would incorporate a variety of sustainable design features to reduce emissions associated with transportation and energy, the primary contributors to criteria air pollutant emissions. For these reasons, the project would not fundamentally conflict with the 2017 Clean Air Plan. Therefore, the project would have a less-than-significant impact. b) Would the project result in a cumulative considerable net increase in any criteria pollutant for which the project region is in nonattainment under an applicable federal or state ambient air quality standard?
Regional Criteria Pollutant and Precursor Emissions
Construction
Construction of the project would generate ROG, nitrogen oxides (NOX), PM10, and PM2.5 emissions that could result in short-term air quality effects. Construction would start in 2026 and be completed over approximately 20 months. Activities during construction would include site preparation and underground utility work, grading, geothermal construction, building construction, paving, and architectural coating applications. Emissions would be released from off-road equipment, employee vehicles, vendor trucks, and haul trucks. Fugitive dust would result from site grading and earthmoving, suspended road dust would result from vehicle travel, and off-gassing would result from architectural coating applications and paving.

Consistent with Air District guidance, average daily emissions have been calculated to assess construction impacts, as shown in Table 2-2 (Air District 2023). Short-term emissions generated by project construction were calculated with use of the California Emissions Estimator Model (CalEEMod), version 2022.1, which relies on vehicle emission factors from CARB’s EMFAC2021, as recommended by the Air District and other air districts in California (California Air Pollution Control Officers Association [CAPCOA] 2022). Modeling was based on default values from CalEEMod, as generated by the model, that consider a project’s location and land use type as well as project-specific information where available, including building type and size, expected construction phase duration, earthwork, and the area to be graded or paved. Daily emissions vary, depending on the type and intensity of construction activities occurring simultaneously.

Detailed model assumptions and inputs for the calculations are provided in Attachment A.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-10 February 2026 Table 2-2. Average Daily Criteria Pollutant Emissions from Project Construction (pounds per day) Construction Year ROGa,b NOXa,b PM10 Exhausta,b PM2.5 Exhausta,b 2026 2 19 1 1
2027 7 8 < 1 < 1
Maximum 7 19 1 1
Threshold 54 54 82 54
Exceeds threshold? No No No No
Source: Attachment A.

Notes: Emissions are rounded to the nearest whole number; exceedances, if they occur, are underlined. a. This is a pollutant or a precursor to a pollutant for which the project area is designated as nonattainment. b. Emissions from mobile sources have been adjusted externally to CalEEMod to remove the emissions benefit from the Advanced Clean Trucks, Zero-Emission Airport Shuttle, Warranty Phase 1, and Heavy-Duty Omnibus Regulation (CARB 2025). Attachment A shows the factors that were used to adjust mobile-source emissions.

NOX = nitrogen oxides; PM10 = particulate matter 10 microns or less in diameter; PM2.5 = particulate matter 2.5 microns or less in diameter; ROG = reactive organic gas As shown in Table 2-2, construction of the project would not generate ROG, NOX, PM10 exhaust, or PM2.5 exhaust emissions that would exceed the applicable Air District thresholds. Project construction would not contribute a significant level of pollution that would degrade regional air quality within the SFBAAB. Therefore, the project would have a less-than-significant impact.

Fugitive Dust
Project construction activities would generate fugitive dust emissions, including both PM10 and PM2.5.

As noted in the Air District CEQA Guidelines, projects that implement the district’s recommended basic best management practices (BMPs) are generally considered to have a less-than-significant impact with respect to construction-related fugitive dust emissions (Air District 2023). Without BMPs, the impact of fugitive dust emissions could be significant. Although the Air District’s BMPs are effective in mitigating mass emissions of fugitive dust, construction activities could still result in a potentially significant impact with respect to the Air District’s health-protective PM2.5 concentration threshold, as discussed further in Impact c, below. To mitigate the impact associated with PM2.5 concentrations during construction, as evaluated in Impact c, one of the Air District’s basic BMPs has been modified to require watering in exposed areas three times per day instead of the standard two. Although the additional watering is not necessary to reduce mass emissions of fugitive dust, the BMPs are relevant to both the mass emissions analysis (Impact b) and the concentration-based analysis (Impact c); therefore, the modified BMPs are presented in this section. Implementation of Mitigation Measure AQ-1, below, would require adherence to the Air District’s BMPs and increased watering in exposed areas. The project’s construction-related fugitive dust emissions would not result in a significant contribution to regional air pollution within the SFBAAB. Therefore, the project would have a lessthan-significant impact with mitigation incorporated.

Mitigation Measure AQ-1: Require Implementation of Modified Bay Area Air District Basic Best Management Practices for Construction-Related Fugitive Dust Emissions The County shall require its contractor(s), as a condition of contracts (e.g., standard specifications), to reduce construction-related fugitive dust emissions by implementing the following modified Air District basic BMPs:

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-11 February 2026  All exposed surfaces (e.g., parking areas, staging areas, soil piles, graded areas, unpaved access roads) shall be watered three times per day.1
 All haul trucks transporting soil, sand, or other loose material off-site shall be covered.  All visible mud or dirt track-out onto adjacent public roads shall be removed using wet power vacuum street sweepers at least once per day. The use of dry power sweeping is prohibited.  All vehicle speeds on unpaved roads shall be limited to 15 mph.  All roadways, driveways, and sidewalks are to be paved as soon as possible. Building pads shall be laid as soon as possible after grading, unless seeding or soil binders are used.  All excavation, grading, and/or demolition activities shall be suspended when average wind speeds exceed 20 mph.
 All trucks and equipment, including their tires, shall be washed prior to leaving the site.  Unpaved roads providing access to sites located 100 feet or more from a paved road shall be treated with a 6- to 12-inch layer of compacted wood chips, mulch, or gravel.  Publicly visible signs shall be posted with the telephone number and name of the person to contact at the lead agency regarding dust complaints. This person shall respond and take corrective action within 48 hours. The Air District’s general air pollution complaints number shall also be visible to ensure compliance with applicable regulations.

The County or its contractor(s) shall submit evidence of compliance to the County, including relevant documentation (e.g., engineering plans, training records, inspection and testing protocols), demonstrating implementation of the modified BMPs prior to grading permit issuance.

Operation
The project is expected to be fully operational by 2027. Project operation would generate emissions of ROG, NOX, PM10, and PM2.5 that could result in long-term air quality effects during operations.

Emissions would stem from motor vehicles traveling to and from the project site, operation of landscape equipment, the use of cleaning supplies, and the periodic reapplication of architectural coatings.

Emissions from operational sources were calculated using CalEEMod, version 2022.1, as recommended by the Air District and other air districts in California (CAPCOA 2022). Modeling was based on project-specific information where available, including information regarding the land use categories and stationary equipment, and default values from CalEEMod, which are generated by the model according to a project’s location and land use type.

Because the project would be all electric, it would not result in any on-site criteria pollutant emissions; therefore, there are no energy sources associated with the project. Table 2-3 presents the project’s estimated average daily operational emissions, which are evaluated against the applicable Air District thresholds. Detailed model assumptions and inputs for the calculations are provided in Attachment A.
1 This component of the mitigation measure modifies Air District BMPs by increasing the watering frequency from two times per day to three times. The increased frequency is not needed to mitigate Impact b but is needed to mitigate Impact c.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-12 February 2026 Table 2-3. Average Daily Operational Criteria Pollutant Emissions (pounds per day) Source ROGa NOXa PM10a PM2.5a
Mobile sources 7 5 9 2
Area sources 3 < 1 < 1 < 1
Energy sources — — — —
Total Project 10 5 9 2
Threshold 54 54 82 82
Exceeds threshold? No No No No
Source: Attachment A.

Notes: Emissions are rounded to the nearest whole number. a. This is a pollutant or a precursor to a pollutant for which the project area is designated as nonattainment.

NOX = nitrogen oxides; PM10 = particulate matter 10 microns or less in diameter; PM2.5 = particulate matter 2.5 microns or less in diameter; ROG = reactive organic gas As shown in Table 2-3, project operation would not generate ROG, NOX, PM10, or PM2.5 emissions in excess of the Air District’s numeric thresholds. Project operation would not contribute to a significant level of pollution that would degrade regional air quality within the SFBAAB. Therefore, the project would have a less-than-significant impact.

Localized Carbon Monoxide Emissions
Heavy traffic congestion can contribute to high levels of CO. Individuals exposed to such “hot spots” may have a greater likelihood of developing adverse health effects. The Air District has adopted screening criteria that provide a conservative indication of whether project-generated traffic would cause a potential CO hot spot. If the screening criteria are not met, a quantitative analysis, through site-specific dispersion modeling of project-related CO concentrations, is not necessary. A project would not cause localized violations of the CAAQS for CO if the Air District’s CO screening criteria, summarized below, are met (Air District 2023).
• The project is consistent with an applicable congestion management program established by the County congestion management agency for designated roads or highways, the regional transportation plan, and local congestion management agency plans. • Project-generated traffic would not increase traffic volumes at affected intersections to more than 44,000 vehicles per hour.
• Project-generated traffic would not increase traffic volumes at affected intersections to more than 24,000 vehicles per hour where vertical and/or horizontal mixing is substantially limited (e.g., tunnel, garage, bridge underpass, natural or urban street canyon, below-grade roadway).

Based on information provided by the project’s traffic consultant, TJKM, none of the study intersections are designated under the Congestion Management Program (CMP). Therefore, CMP requirements do not apply, and the project would not conflict with the applicable CMP. As a result, the Air District’s screening volumes are used to assess the project’s potential for localized CO hot spots. Based on the volume summaries provided by TJKM, maximum traffic volumes at the affected intersections would not exceed the screening criterion of 44,000 vehicles per hour or the screening criterion of 24,000 vehicles per hour recommended for areas where vertical or horizontal mixing is substantially limited. Consequently, the project would not exceed the Air District’s screening thresholds for local CO hot spots and would not be expected to cause or contribute to CO

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-13 February 2026 concentrations that would exceed the applicable NAAQS or CAAQS. Therefore, the project would have a less-than-significant impact.

Health Effects of Regional Criteria Pollutant and Precursor Emissions The Air District’s regional thresholds consider existing air quality concentrations and attainment or nonattainment designations under the NAAQS and CAAQS. The NAAQS and CAAQS are informed by a wide range of scientific evidence that demonstrates there are known safe concentrations of criteria pollutants. Although the Air District recognizes that air quality is a cumulative problem, it considers projects that generate criteria pollutant and O3 precursor emissions below the thresholds to be minor in nature; therefore, such projects would not adversely affect air quality to the extent that the healthprotective NAAQS or CAAQS would be exceeded.

As shown in Tables 2-2 and 2-3, project construction and operation would not generate regional criteria pollutants in excess of the applicable Air District thresholds. As such, the project would not be expected to contribute a significant level of air pollution that would degrade air quality within the SFBAAB.

Therefore, the project would have a less-than-significant impact. c) Would the project expose sensitive receptors to substantial pollutant concentrations? Diesel Particulate Matter and PM2.5
The project would generate emissions of diesel particulate matter (DPM), 2 a TAC, and fine particulate
matter (PM2.5) during construction. These emissions would stem primarily from the use of off-road diesel-powered equipment and heavy-duty trucks. PM2.5 emissions, including both diesel and non-diesel exhaust as well as fugitive dust, would be generated by off-road equipment, on-site soil disturbance, and vehicle travel by heavy-duty trucks and construction workers. Given the proximity of sensitive receptors to the project site, a health risk assessment (HRA) was conducted to evaluate potential impacts from these emissions.

The project may also generate minor DPM emissions from heavy-duty truck activity and PM2.5 emissions from employee vehicle trips during operation. However, because most operational trips would be made in passenger cars and light-duty trucks, which typically do not emit significant levels of DPM, the number of trips with the potential to generate DPM would be minimal. Furthermore, because operational activities would not coincide with construction, and PM2.5 emissions from mobile sources during operation would be substantially lower than those during construction, operational emissions are not expected to influence the maximum annual PM2.5 concentration resulting from the project. As such, DPM and PM2.5 emissions from mobile operational sources were not included in the HRA.

The HRA was prepared by using the AERMOD View 13.0.0 air dispersion model and incorporating the most current methodology outlined in the Air District CEQA Guidelines (Air District 2023). Table 2-4 presents the unmitigated incremental health risks for off-site residential, student, and worker receptors within 1,000 feet of the project site. The results reflect implementation of the Air District’s basic dustreducing BMPs, as written in the Air District CEQA Guidelines. Because the BMPs are required for a project’s impact to be considered less than significant with respect to mass emissions of fugitive dust, their implementation is required regardless of the HRA results. Therefore, the scenario shown in Table 2-4 is considered unmitigated for the purposes of the HRA.3 2 Per Air District guidance, PM10 exhaust is used as a surrogate for DPM. 3 The mitigated HRA scenario incorporates the modified set of BMPs required by Mitigation Measure AQ-1, as discussed below.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-14 February 2026 Table 2-4. Estimated Unmitigated Project-Level Health Risk Results from Construction Off-site Receptor Type
Cancer Risk
(cases per million)a
Non-Cancer
Chronic Risk
Annual PM2.5
Concentrations (µg/m3)
MEIR – Residentb
Project construction 13.5 0.02 0.14
Threshold 10 1.0 0.3
Exceeds threshold? Yes No No
MEIR – Studentc
Project construction 20.5 0.01 0.09
Threshold 10 1.0 0.3
Exceeds threshold? Yes No No
MEIR – Workerd
Project construction 2.1 0.04 0.31
Threshold 10 1.0 0.3
Exceeds threshold? No No Yes
Source: See Attachment A for detailed modeling files.

Notes:
a. The evaluation of cancer risks in the HRA was based on an exposure duration of 1.56 years for project construction. b. The resident MEIR is approximately 20 feet west of the project site at UTM (x, y) coordinates 614271.18, 4200418.41.
c. The student MEIR is at the Goddard School of Brentwood, approximately 125 feet north of the project site at UTM (x, y) coordinates 614351.18, 4200538.41.
d. The worker MEIR is approximately 20 feet north of the project site at UTM (x, y) coordinates 614491.18, 4200458.41.

Exceedances are bolded and underlined.

MEIR = maximally exposed individual receptor; PM2.5 = particulate matter with an aerodynamic diameter of 2.5 or less µg/m3 = micrograms per cubic meter
As shown in Table 2-4, the unmitigated results would not exceed the non-cancer risk hazard index threshold. However, the project would result in cancer risks that would exceed the applicable threshold for residential and student receptors as well as the annual PM2.5 concentration threshold for worker receptors. Therefore, impacts would be potentially significant. Implementation of Mitigation Measure AQ-1 (refer to Impact b) would reduce construction-related PM2.5 emissions by requiring the Air District’s basic dust-reducing BMPs, with a modification to require exposed surfaces to be watered three times daily instead of two times daily. This mitigation measure would reduce worker exposure to PM2.5 concentrations during construction. Implementation of Mitigation Measure AQ-2, below, would reduce construction-related DPM emissions by requiring EPA Tier 4 Final diesel equipment. The primary intent of this mitigation measure is to reduce the significant cancer risk at resident and student receptors. Results for the mitigated scenario are presented in Table 2-5.

Table 2-5. Estimated Mitigated Project-Level Health Risk Results from Construction Off-site Receptor Type
Cancer Risk
(cases per million)a
Non-Cancer
Chronic Risk
Annual PM2.5
Concentrations (µg/m3)
MEIR – Residentb
Project construction 2.5 < 0.01 0.09
Threshold 10 1.0 0.3

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-15 February 2026 Off-site Receptor Type
Cancer Risk
(cases per million)a
Non-Cancer
Chronic Risk
Annual PM2.5
Concentrations (µg/m3)
Exceeds threshold? No No No
MEIR – Studentc
Project construction 3.8 < 0.01 0.05
Threshold 10 1.0 0.3
Exceeds threshold? No No No
MEIR – Workerd
Project construction 0.4 0.01 0.2
Threshold 10 1.0 0.3
Exceeds threshold? No No No
Source: See Attachment A for detailed modeling files.

Notes:
a. The evaluation of cancer risk in the HRA was based on an exposure duration of 1.56 years for project construction. b. The resident MEIR is approximately 20 feet west of the project site at UTM (x, y) coordinates 614271.18, 4200418.41.
c. The student MEIR is at the Goddard School of Brentwood, approximately 125 feet north of the project site at UTM (x, y) coordinates 614351.18, 4200538.41.
d. The worker MEIR is approximately 20 feet north of the project site at UTM (x, y) coordinates 614491.18, 4200458.41.

MEIR = maximally exposed individual receptor; PM2.5 = particulate matter with an aerodynamic diameter of 2.5 or less; µg/m3 = micrograms per cubic meter
As shown in Table 2-5, with implementation of Mitigation Measure AQ-1 and Mitigation Measure AQ-2, cancer risks and annual PM2.5 concentrations would be below the applicable thresholds for all receptor types. Project-generated construction emissions would not expose sensitive receptors to substantial pollutant concentrations or associated health risks. Therefore, the project would have a less-than-significant impact with mitigation incorporated.

Mitigation Measure AQ-1: Require Implementation of Modified Bay Area Air District Basic Best Management Practices for Construction-Related Fugitive Dust Emissions Refer to Impact b, above.

Mitigation Measure AQ-2: Use Clean Diesel-Powered or Electric Equipment during Construction to Control Construction-Related Emissions
The County shall require its contractor(s), as a condition of contracts (e.g., standard specifications), to ensure that all off-road diesel-powered equipment greater than 50 horsepower used during construction is equipped with EPA-approved Tier 4 Final engines or cleaner4 to reduce exhaust PM2.5 emissions. The construction contractor shall submit evidence of the use of EPA-approved Tier 4 Final engines or cleaner to the Contra Costa County Public Works Department prior to the commencement of project construction activities. Exceptions can be made in limited circumstances when Tier 4 Final engines are not available or otherwise cannot be feasibly obtained. The County or its contractor(s) must identify the pieces of equipment that would not have Tier 4 Final engines, submit evidence documenting the unavailability or infeasibility, and ensure that the equipment has an engine that meets the 4 Cleaner engine technology includes electric equipment and engines built to CARB Tier 5 engine standards, which are expected to begin in 2028.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-16 February 2026 cleanest feasible emission standard. The County shall present evidence in a publicly accessible location, documenting that the equipment substitution(s) would not cause an exceedance of the Air District cancer risk threshold at any receptor.

Cumulative Health Risk Assessment
According to the Air District CEQA Guidelines, risk levels from project-generated sources and existing sources within 1,000 feet of a project site should be combined and compared to the Air District’s cumulative health risk thresholds (Air District 2023).

Under the proposed project, existing and project-generated health risks could contribute to a cumulative health risk for sensitive receptors near the project site. Potential existing TAC sources include permitted stationary sources (e.g., emergency generators and gas stations), roadways, railways, and other development projects in the surrounding area. Within 1,000 feet of the project site, there is one permitted facility: a gasoline dispensing facility, Brentwood Petroleum, at 7920 Brentwood Boulevard. This facility is approximately 920 feet south of the project site. The Air District’s inventory of stationary health risks was used to estimate the combined level of health risk from the existing permitted facility, in combination with the project’s contributions. Mobile sources on nearby railways and roadways such as Sand Creek Road and SR 4 would also generate TAC emissions. A railway is approximately 1,700 feet west of the project site; SR 4 is approximately 2.1 miles west of the project site. Geographic information system (GIS) raster files provided by the Air District were used to estimate railway and roadway emissions within 1,000 feet of the project site (Air District 2022). None of the development projects that have recently been approved or may soon be approved by the County would be close enough (i.e., within 1,000 feet) to the site to combine with project-generated health risks.

Table 2-6 summarizes the mitigated health risks for the project’s maximally exposed receptors, along with contributions from existing stationary and mobile sources within 1,000 feet of the site.

The combined health risk values are compared to the Air District’s cumulative thresholds.

Additional details on individual background source contributions are provided in Attachment A.

As shown in Table 2-6, health risks associated with existing stationary, roadway, and railway sources in combination with the project would not exceed the Air District’s cumulative thresholds.

All results would be below the Air District’s thresholds by a substantial margin. Therefore, the cumulative effect of health risks associated with TACs emitted by the project in combination with health risks associated with existing TAC sources would not result in cumulatively considerable local health risks at sensitive land uses. Therefore, the project would have a less-than-significant impact.

Table 2-6. Cumulative Mitigated Health Risk Results
Pollutant/Receptor Type
Cancer Risk (cases
per million)
Non-Cancer
Chronic Risk
Annual PM2.5
Concentration (µg/m3)
MEIR – Resident (Mitigated)
Existing sources
Stationary sourcesa — — —
Roadway sources 4.4 0.02 0.12
Rail sources 0.1 < 0.01 < 0.01
Total 4.5 0.02 0.12

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-17 February 2026 Pollutant/Receptor Type
Cancer Risk (cases
per million)
Non-Cancer
Chronic Risk
Annual PM2.5
Concentration (µg/m3)
Project construction 2.5 < 0.01 0.09
Total cumulative 7.0 0.02 0.21
Threshold 100 10 0.8
Exceeds threshold? No No No
MEIR – Student (Mitigated)
Existing sources
Stationary sourcesa — — —
Roadway sources 5.5 0.02 0.20
Rail sources 0.1 < 0.01 < 0.01
Total 5.5 0.02 0.20
Project construction 3.8 < 0.01 0.05
Total cumulative 9.3 0.03 0.26
Threshold 100 10 0.8
Exceeds threshold? No No No
MEIR – Worker (Mitigated)
Existing sources
Stationary sourcesa — — —
Roadway sources 4.0 0.01 0.09
Rail sources < 0.1 < 0.01 < 0.01
Total 4.0 0.01 0.09
Project construction 0.4 0.01 0.20
Total Cumulative 4.4 0.02 0.29
Threshold 100 10 0.8
Exceeds threshold? No No No
Source: Attachment A.
a.The permitted stationary source is 920 feet south of the project site and more than 280 meters from the maximally exposed residential, student, and worker receptors. Because the Air District’s distance adjustment factors are defined only for receptors within 280 meters, health risk values from this source are not quantified for these receptors.

MEIR = maximally exposed individual receptor; PM2.5 = particulate matter with an aerodynamic diameter of 2.5 or less; µg/m3 = micrograms per cubic meter
Asbestos
Asbestos is a naturally occurring mineral that was previously used in building construction due to its heat resistance and strong insulating properties. Exposure to asbestos, however, has been shown to cause many disabling and fatal diseases, including lung cancer, mesothelioma, and pleural plaques.

Because the site is currently an undeveloped lot, construction activities would not involve the demolition of existing structures. As such, there would be no anticipated disturbance of asbestoscontaining materials, and project construction activities would not pose a risk of asbestos exposure to workers or nearby receptors. 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 2-18 February 2026 d) Would the project result in other emissions (such as those leading to odors) adversely affecting a substantial number of people?
Odor impacts could occur if a project were to introduce a new odor source near existing sensitive receptors. The project site is surrounded primarily by commercial and residential uses; a day-care center is located to the north. Consequently, students, residents, and workers are within 1,000 feet of the project site. According to the Air District, land uses associated with odor complaints include wastewater treatment plants, landfills, food manufacturing plants, and other types of odorgenerating facilities, as detailed in Table 5-4 of the Air District CEQA Guidelines (Air District 2023).

The project does not propose any of these uses and would not result in changes that would introduce odor-generating facilities.

Potential odor emitters during construction activities include diesel exhaust, asphalt paving, and the use of architectural coatings and solvents. During operation, odors could result from vehicle exhaust and the reapplication of architectural coatings, but these would be limited to areas adjacent to the building. Both construction equipment- and generator-related odors would be temporary and would dissipate rapidly with distance. In addition, the project would comply with the Air District’s Regulation 7 (Odorous Substances), which limits emissions of odorous compounds from all nonexempt entities within the Air District’s jurisdiction. Accordingly, project construction and operation are not expected to create objectionable odors that would affect a substantial number of people.

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

2.3.2 Sources of Information
Bay Area Air District. 2017. Final 2017 Clean Air Plan. Adopted April 19. Available:
https://www.baaqmd.gov/~/media/files/planning-and-research/plans/2017-clean-airplan/attachment-a_-proposed-final-cap-vol-1-pdf.pdf?la=en. Accessed: April 2025. ———. 2022. Health Risk Screening and Modeling. Available: https://www.baaqmd.gov/plans-andclimate/california-environmental-quality-act-ceqa/ceqa-tools/health-risk-screening-andmodeling. Accessed: April 2025. ———. 2023. California Environmental Quality Act Air Quality Guidelines. Available:
https://www.baaqmd.gov/plans-and-climate/california-environmental-quality-actceqa/updated-ceqa-guidelines. Accessed: April 2025. ———. 2024. Stationary Source Screening Map. Available: https://baaqmd.maps.arcgis.com/apps/ webappviewer/index.html?id=845658c19eae4594b9f4b805fb9d89a3. Accessed: April 2025.

California Air Pollution Control Officers Association. 2022. California Emissions Estimator Model User Guide. April. Available: https://caleemod.com/documents/user-guide/CalEEMod_User_Guide_ v2022.1.pdf. Accessed: April 2025.

California Air Resources Board. 2023. Maps of State and Federal Area Designations. Available:
https://ww2.arb.ca.gov/resources/documents/maps-state-and-federal-area-designations.

Accessed: April 2025.

California Air Resources Board. 2025. EMFAC Off-Model Adjustment Factors to Remove Emissions Benefits of Advanced Clean Trucks, Zero-Emission Airport Shuttle, Warranty Phase 1, and HeavyDuty Omnibus Regulations. Available: https://www.epa.gov/system/files/documents/2025- 12/attachment-a-description-of-emfac2021-adjustment-factors.pdf. Accessed: January 12, 2026.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-19 February 2026 Office of Environmental Health Hazard Assessment. 2023. CalEnviroScreen 4.0. Available:
https://experience.arcgis.com/experience/ed5953d89038431dbf4f22ab9abfe40d/#data_s=id %3AdataSource_25-17c3d89e7e2-layer-1%3A3322. Accessed: April 2025.

Tri Delta Transit. 2025. 300X Brentwood Park & Ride/Antioch BART Schedule. Effective January 12, 2025. Available: https://trideltatransit.com/wp-content/uploads/2024/05/300X-Weekdaysonly.pdf. Accessed: June 2025.

U.S. Environmental Protection Agency. 2025. California Nonattainment/Maintenance Status for Each County by Year for All Criteria Pollutants. Available: https://www3.epa.gov/airquality/ greenbook/anayo_ca.html. Accessed: June 2025.

2.4 Biological Resources
Potentially
Significant
Impact
Less than
Significant with
Mitigation
Incorporated
Less-thanSignificant
Impact No Impact
Would the project:
a) Have a substantial adverse effect, either directly or through habitat modifications, on any species identified as a candidate, sensitive, or special-status species in local or regional plans, policies, or regulations or by the California Department of Fish and Wildlife or U.S. Fish and Wildlife Service?
b) Have a substantial adverse effect on any riparian habitat or other sensitive natural community identified in local or regional plans, policies, regulations or by the California Department of Fish and Wildlife or U.S. Fish and Wildlife Service?
c) Have a substantial adverse effect on state or federally protected wetlands (including, but not limited to, marshes, vernal pools, coastal areas) through direct removal, filling, hydrological interruption, or other means?
d) Interfere substantially with the movement of any native resident or migratory fish or wildlife species, or with established native resident or migratory wildlife corridors, or impede the use of native wildlife nursery sites?
e) Conflict with any local policies or ordinances protecting biological resources, such as a tree preservation policy or ordinance?
f) Conflict with the provisions of an adopted habitat
conservation plan, natural community conservation plan, or other approved local, regional, or state habitat conservation plan?

2.4.1 Discussion
The project site is a disturbed vacant lot within an urbanized area. Vegetation on the lot is dominated by non-native annual grasses; a few landscape trees are present along the perimeter in adjacent properties. Based on a review of historic aerial photos, the project site appears to be routinely disked. The developed urban area surrounding the project site has existing sources of ambient light, such as streetlights, vehicle headlights, and residential lighting. □
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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 2-20 February 2026 East Contra Costa County HCP/NCCP Participation
The project is within the adopted habitat conservation plan/natural community conservation plan (HCP/NCCP) urban development area and a covered activity under bullet two (public service facilities). The HCP/NCCP is intended to provide an effective framework for protecting natural resources and special-status species recovery in eastern Contra Costa County while improving and streamlining the environmental permitting process for impacts on these species and associated habitats. The East Contra Costa County Habitat Conservancy was created to oversee assembly and operation of the HCP/NCCP preserve system and ensure compliance with all terms of the HCP/NCCP, permits, and implementing agreement. Participation in the HCP/NCCP results in payment of fees to mitigate impacts on open space, habitats, and covered species. An assessment of special-status species not covered by the East Contra Costa County HCP/NCCP for the project was prepared by Dudek (Dudek 2024), and an application form and planning survey report to comply with and receive permit coverage under the East Contra Costa County HCP and NCCP was prepared for the proposed project by Dudek (Dudek 2025) (refer to Attachment B). To characterize biological resources on the project site, searches of the California Department of Fish and Wildlife (CDFW) California Natural Diversity Database (CNDDB) and California Native Plant Society (CNPS) Rare Plant Inventory were conducted (CDFW 2025; CNPS 2025). In addition, a U.S. Fish and Wildlife Service (USFWS) species list was obtained through the Information for Planning and Consultation (IPaC) web portal (USFWS 2025). A reconnaissance-level field survey was conducted on December 11, 2024, by a Dudek biologist.
a) Would the project have a substantial adverse effect, either directly or through habitat modifications, on any species identified as a candidate, sensitive, or special-status species in local or regional plans, policies, or regulations or by the California Department of Fish and Wildlife or U.S. Fish and Wildlife Service?
Special-Status Plants
Special-status plant species were not observed during the field survey and are not expected to occur on the project site due to a lack of suitable habitat. Therefore, the project would have no impact.

Special-Status Wildlife
The database searches identified 71 special-status wildlife species that are occurring or potentially occurring in the project vicinity (CDFW 2025; USFWS 2025). Of these, 68 species were eliminated from consideration due to the absence of suitable habitat within the project site, the project’s location outside of the species’ known range, or the presence of urbanization and human activity in areas surrounding the project site that would render potentially suitable habitat unsuitable for some species (Dudek 2025). The 68 species are not discussed further.

Planning surveys and a review of occurrence databases indicated that there is moderate potential for western burrowing owl (Athene cunicularia), Swainson’s hawk (Buteo swainsoni), white-tailed kite (Elanus leucurus), and non-special-status migratory or nesting birds to occur on the project site.

Project construction would result in the loss of suitable habitat. Furthermore, construction activities may result in injury, mortality, or disruption of normal behaviors if the aforementioned species are present. During project operations, landscape and building maintenance, the presence of humans and vehicles during weekday daytime shifts (7:00 a.m.–5:30 p.m.), and permanent nighttime lighting for security purposes may result in injury, mortality, or disruption of normal behaviors for specialPage 78 of 1860 Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-21 February 2026 status wildlife. Therefore, project impacts would be potentially significant. The mitigation measures described below, which are consistent with the species-level measures in the East Contra Costa County HCP (Jones and Stokes 2006), are provided to reduce impacts to a less-than-significant level.

Western Burrowing Owl
Western burrowing owl is a candidate for listing under the California Endangered Species Act (CESA) and a California Species of Special Concern. Ruderal land cover within the project site is considered suitable habitat and therefore would be able to support this species. In addition, numerous California ground squirrel burrows are present on the east side of the project site.

However, no burrowing owls, or indicators of their presence, were observed during the planning survey, and none of the burrows on-site are of a diameter that would be suitable for burrowing owl (Dudek 2024).

One CNDDB occurrence of western burrowing owl overlaps the northeast corner of the project site; however, the occurrence appears to have been extirpated by development and passive relocation (Occurrence No. 1155) (CDFW 2025). Nine other CNDDB occurrences have been reported within 1 mile of the project site. Many were in areas that are now densely developed; these have most likely been extirpated. No additional occurrences within proximity of the project site have been recorded since 2012.

Although no burrows of suitable size were documented during the planning survey, site conditions may change. In addition, California ground squirrels and gophers, which can create burrows, are present on-site. Therefore, potentially suitable burrows could be present during project construction.

Project construction and operations could result in injury, mortality, or disturbance of normal behaviors for western burrowing owl if present, which would be a potentially significant impact.

Implementation of Mitigation Measure BIO-1, below, would require preconstruction surveys; if burrowing owl is present, avoidance measures and construction monitoring would be implemented.

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

Mitigation Measure BIO-1: Preconstruction Survey for Burrowing Owls Prior to any ground disturbance related to covered activities, a qualified biologist with experience identifying burrowing owl and its habitat will conduct a preconstruction survey in areas identified in the planning surveys as having potential burrowing owl habitat. The surveys will establish the presence or absence of western burrowing owl and/or habitat features and evaluate use by owls in accordance with CDFW survey guidelines (California Department of Fish and Game 2012).

On the site where the activity is proposed, the biologist will survey all suitable burrowing owl habitat within the proposed disturbance footprint and a 500-foot radius from the perimeter of the proposed footprint to identify burrows and owls. Adjacent parcels under different land ownership or without suitable habitat (e.g., sites that are paved) will not be surveyed. Surveys should take place near sunrise or sunset in accordance with CDFW guidelines. All burrows or burrowing owls will be identified and mapped. Surveys will take place no more than 30 days prior to construction. During the breeding season (February 1–August 31), surveys will document whether burrowing owls are nesting in or directly adjacent to disturbance areas.

During the nonbreeding season (September 1–January 31), surveys will document whether burrowing owls are using habitat in or directly adjacent to any disturbance area. Survey results

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-22 February 2026 will be valid only for the season (breeding or nonbreeding) during which the survey is conducted.

This measure incorporates avoidance and minimization guidelines from CDFW’s Staff Report on Burrowing Owl Mitigation (California Department of Fish and Game 2012).

If burrowing owls are found during the breeding season (February 1–August 31), project construction activities will avoid all nest sites that could be disturbed by project construction during the remainder of the breeding season or while the nest is occupied by adults or young.

Avoidance will include establishment of a non-disturbance buffer zone (described below).

Construction may occur during the breeding season if a qualified biologist monitors the nest and determines that the birds have not begun egg-laying and incubation or that juveniles from the occupied burrows have fledged. During the nonbreeding season (September 1–January 31), construction activities will avoid the owls and the burrows they are using, to the extent possible.

Avoidance will include the establishment of a buffer zone (described below).

During the breeding season, buffer zones of at least 250 feet, in which no construction activities can occur, will be established around each occupied burrow (nest site). Buffer zones of 160 feet will be established around each burrow being used during the nonbreeding season. The buffers will be delineated by highly visible temporary construction fencing.

If occupied burrows for burrowing owls cannot be avoided, passive relocation will be implemented during the nonbreeding season (September 1–January 31) prior to construction activities.

If passive relocation is proposed, at least 30 days prior to any ground-disturbing activities, the County will prepare and submit a burrowing owl relocation plan to be approved by CDFW within 14 days. The burrowing owl relocation plan will describe site-specific passive relocation procedures, which will follow the most current agency-accepted methodology. Included will be procedures and materials for passive relocation with and without exclusion, the criteria and timing for the use of exclusion devices, the names and qualifications of biologists, procedures for monitoring burrows identified for passive relocation, information regarding the timing for burrow excavation and construction initiation, and reporting requirements.

Swainson’s Hawk
Swainson’s hawk is listed as Threatened under CESA. No trees are present on the project site; however, trees that could be suitable for nesting were documented adjacent to and within 1,000 feet of the project site. Ruderal portions of the project site provide suitable low-quality foraging habitat for Swainson’s hawk, and suitable prey species, such as California ground squirrel and gophers, are present (Dudek 2024).

One CNDDB occurrence overlaps the project site (Occurrence #1911, from 1921). However, this occurrence, which was roughly mapped to the city of Brentwood, describes a nest located along a slough, which is not present on-site (CDFW 2025). One other occurrence was reported 0.6 mile from the project site (Occurrence # 1712, from 2006) (CDFW 2025).

Project construction would result in the loss of potential foraging habitat. Construction and operations could result in injury, mortality, or disturbance of normal behaviors for Swainson’s hawk if present, a potentially significant impact. Implementation of Mitigation Measure BIO-2, below, would require preconstruction surveys; if Swainson’s hawk is present, avoidance measures and

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-23 February 2026 construction monitoring would be implemented. Therefore, the project would have a less-thansignificant impact with mitigation incorporated.

Mitigation Measure BIO-2: Preconstruction Survey and Avoidance, Minimization, and Mitigation Measures for Swainson’s Hawks
Preconstruction Survey
Prior to any ground disturbance related to construction activities during the nesting season (March 15–September 15), a qualified biologist will conduct a preconstruction survey no more than 1 month prior to construction to establish whether any Swainson’s hawk nests within 1,000 feet of the project site are occupied. If potentially occupied nests are within 1,000 feet but off the project site, then their occupancy will be determined by observations from public roads or by observations of Swainson’s hawk activity (e.g., foraging) near the project site. If nests are occupied, minimization measures and construction monitoring will be required (see below).

Avoidance and Minimization and Construction Monitoring
During the nesting season (March 15–September 15), project construction activities within 1,000 feet of occupied nests or nests that are under construction will be prohibited to prevent nest abandonment. If site-specific conditions or the nature of the activities (e.g., dense vegetation, limited activities) indicate that a smaller buffer could be used, the qualified biologist will coordinate with CDFW to determine the appropriate buffer size.

If young fledge prior to September 15, covered activities can proceed normally. If the active nest is shielded from view as well as noise from the project site by other development, topography, or other features, the County can coordinate with CDFW to gain approval for waiver of this measure. While the nest is occupied, activities outside the buffer can take place.

All active nest trees will be preserved on-site, if feasible. Nest trees, including non-native trees, lost to covered activities will be mitigated by the project proponent, according to the requirements below.

Mitigation for Loss of Nest Trees
The loss of non-riparian Swainson’s hawk nest trees will be mitigated by the project proponent, as follows:
 If feasible on-site, planting 15 saplings for every tree lost, with the objective of having at least five mature trees established for every tree lost, according to the requirements listed below.

AND either
 Paying the implementing entity an additional fee to purchase, plant, maintain, and monitor 15 saplings on the HCP/NCCP preserve system for every tree lost, according to the requirements listed below, OR
 The project proponent planting, maintaining, and monitoring 15 saplings for every tree lost at a site to be approved by the implementing entity (e.g., within an HCP/NCCP preserve or existing open space linked to HCP/NCCP preserves), according to the requirements listed below.

The following requirements will be met for all planting options:

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-24 February 2026  Tree survival shall be monitored at least annually for 5 years, then every other year until year 12. All trees lost during the first 5 years will be replaced. Success will be reached at the end of 12 years if at least five trees per lost tree survive without supplemental irrigation or protection from herbivory. Trees must also survive for at least 3 years without irrigation.  Irrigation and fencing to protect the site from deer and other herbivores may be needed for the first several years to ensure maximum tree survival.  Native trees suitable for this site should be planted. When site conditions permit, a variety of native trees should be planted for each tree lost to provide trees with different growth rates, maturation rates, and life spans and provide a variety of tree canopy structures for Swainson’s hawk. This variety will help to ensure that nest trees will be available in the short term (5 to 10 years for cottonwoods and willows) and in the long term (e.g., valley oak, sycamore). This will also minimize the temporal loss of nest trees.  Riparian woodland restoration conducted as a result of covered activities (i.e., loss of riparian woodland) can be used to offset the nest tree planting requirement above if the nest trees are riparian species.
 Whenever feasible and when site conditions permit, trees should be planted together in clumps or with existing trees to provide larger areas of suitable nesting habitat and create a natural buffer between nest trees and adjacent development (if plantings occur on the development site).
 Whenever feasible, plantings on the site should occur closest to the suitable foraging habitat outside the urban development area.
 Trees planted in the HCP/NCCP preserves or other approved off-site location will occur within the known range of Swainson’s hawk in the inventory area and as close as possible to high-quality foraging habitat.

White-Tailed Kite
White-tailed kite is a California Fully Protected species. The project site contains suitable open habitat and small mammal prey species. Trees adjacent to the project site are suitable for nesting by this species. Four CNDDB occurrences between 2004 and 2017 were 2.9 to 3.1 miles north of the project site (CDFW 2025).

Project construction and operations could result in injury, mortality, or disturbance of normal behaviors of white-tailed kite if the species is present, a potentially significant impact.

Implementation of Mitigation Measure BIO-2, above, and Mitigation Measure BIO-3, below, would require pre-construction surveys for nesting Swainson’s hawks and non- special-status migratory and nesting birds, which would also detect any white-tailed kites nesting in the site vicinity, and avoidance measures and construction monitoring would be required if the species is present. Therefore, the project would have a less-than-significant impact with mitigation incorporated.

Non-Special-Status Migratory and Nesting Birds
Non-special-status migratory and nesting birds are protected by the federal Migratory Bird Treaty Act (MBTA). Disturbing or destroying active nests is a violation of the MBTA. In addition, nests and eggs are protected under California Fish and Game Code Section 3503.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-25 February 2026 The ruderal land cover on the project site and the adjacent trees may provide suitable habitat for several migratory and nesting bird species, such as red-tailed hawk (Buteo jamaicensis), mourning dove (Zenaida macroura), and savannah sparrow (Passerculus sandwichensis).

Project construction and operations could result in injury, mortality, or disturbance of normal behaviors for non-special-status migratory and nesting birds if present, a potentially significant impact. Implementation of Mitigation Measure BIO-3, below, would require preconstruction surveys; if nesting birds are present, avoidance measures and construction monitoring would be implemented. Therefore, the project would have a less-than-significant impact with mitigation incorporated.

Mitigation Measure BIO-3: Preconstruction Survey for Nesting Birds To avoid direct impacts on nesting birds, the following measures would be implemented:
 Vegetation removal and initial ground disturbance at the project site will be conducted outside of the nesting season (February–September) to the extent feasible. If not feasible, the measures detailed below will be implemented to avoid or minimize impacts on nesting birds.
 A qualified biologist shall conduct a preconstruction survey for nesting birds no more than 7 days prior to vegetation or structure removal or any ground-disturbing activities conducted during the nesting season (February–September). The survey shall cover the limits of construction as well as suitable nesting habitat within 1,000 feet for raptors and 100 feet for other nesting birds, as feasible and accessible.  If any active nests are observed during surveys, a qualified biologist shall establish a suitable avoidance buffer around the active nest. The buffer distance shall typically range from 50 to 500 feet and be based on factors such as the species of bird, topographic features, the intensity and extent of the disturbance, the timing relative to the nesting cycle, and the anticipated construction schedule. To avoid active nests, the limits of construction shall be established in the field with flagging, fencing, or other appropriate barriers and shall be maintained until the chicks have fledged and the nests are no longer active, as determined by the qualified biologist.
 If vegetation removal activities are delayed, additional nest surveys shall be conducted so that no more than 7 days elapse between the survey and vegetation removal activities.  If an active nest is identified in or adjacent to the construction zone after construction has started, work in the vicinity of the nest shall be halted until the qualified biologist can provide appropriate avoidance and minimization measures, ensuring that the nest will not be disturbed by construction. Appropriate measures may include establishing a nodisturbance buffer until the birds have fledged and/or implementing full-time monitoring by a qualified biologist during construction activities conducted near the nest. b) Would the project have a substantial adverse effect on any riparian habitat or other sensitive natural community identified in local or regional plans, policies, regulations or by the California Department of Fish and Wildlife or U.S. Fish and Wildlife Service?
The project site consists of only Urban and Ruderal land cover types; no riparian habitat or other sensitive natural communities are present. 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 2-26 February 2026 c) Would the project have a substantial adverse effect on state or federally protected wetlands (including, but not limited to, marshes, vernal pools, coastal areas) through direct removal. filling, hydrological interruption, or other means?
No aquatic or wetland features were identified during the planning survey. The topography of the project site is relatively flat, with no depressions or channels. No standing water, aquatic vegetation, or wetlands were documented during the planning survey. Therefore, the project would have no impact.
d) Would the project interfere substantially with the movement of any native resident or migratory fish or wildlife species, or with established native resident or migratory wildlife corridors, or impede the use of native wildlife nursery sites?
The project would not substantially interfere with the movement of any native resident or migratory fish or wildlife species or migratory wildlife corridors or impede the use of wildlife nursery sites. No rookeries or other nursery sites, water bodies, riparian areas, or wildlife corridors are located on the project site. The project site is a flat, grassy undeveloped lot with no trees. Surrounding land uses include residential neighborhoods to the west; commercial buildings to the north; commercial buildings to the east across Brentwood Boulevard; and a grassy agricultural field to the south (Dudek 2024). While the grassy agricultural field may provide some habitat for wildlife, the existing highly urbanized surrounding areas likely obstruct most wildlife movement through the area.

Urban-adapted wildlife would move around the Project site unhindered. Therefore, the project would have a less-than-significant impact.
e) Would the project conflict with any local policies or ordinances protecting biological resources, such as a tree preservation policy or ordinance?
The project would not conflict with any local policies or ordinances protecting biological resources.

There are no trees on the project site. Therefore, the project would have no impact. f) Would the project conflict with the provisions of an adopted habitat conservation plan, natural community conservation plan, or other approved local, regional, or state habitat conservation plan? The project would not conflict with the provisions of an adopted HCP, NCCP, or other approved local, regional, or state HCP. The project is within the urban development area of the East Contra Costa County HCP (Jones and Stokes 2006) and considered a covered activity under the plan. The project has been designed to comply with the provisions of the East Contra Costa County HCP, which include implementing all applicable conservation measures. The project would follow all mitigation measures (as identified above) from the planting survey report and provide mitigation fees to offset impacts in compliance with the HCP/NCCP. New plantings would be a mix of native, droughttolerant plants. In addition, the project would not occur within any East Contra Costa County HCP preserve system lands. Therefore, project impacts would be less than significant.

2.4.2 Sources of Information
California Department of Fish and Game. 2012. Staff Report on Burrowing Owl Mitigation. March 7.

Sacramento, CA. Available: https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=83843.

Accessed: July 7, 2025.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-27 February 2026 California Department of Fish and Wildlife. 2025. California Natural Diversity Database. RareFind, Version 5 (commercial subscription). Sacramento, CA: Biogeographic Data Branch. Available:
http://www.dfg.ca.gov/biogeodata/cnddb/mapsanddata.asp. Accessed July 1, 2025.

California Native Plant Society. 2025. Inventory of Rare and Endangered Plants (online edition, v9-01

1.5). Rare Plant Program. Sacramento, CA. Available: http://www.rareplants.cnps.org. Accessed:

July 1, 2025.

Dudek. 2024. Application form and planning survey report to comply with and receive permit coverage under the East Contra Costa County Habitat Conservation Plan and Natural Community Conservation Plan.

Dudek. 2025. Assessment for Special-Status Species Not Covered by the East Contra Costa County Habitat Conservation Plan/Natural Community Conservation Plan, East County Service Center Project, Brentwood, California (Project WH429A). Memo to Contra Costa County.

Jones & Stokes. 2006. East Contra Costa County Habitat Conservation Plan and Natural Community Conservation Plan. October. (J&S 01478.01.) San José, CA.

U.S. Fish and Wildlife Service. 2025. Information for Planning and Consultation. Available:
http://www.fws.gov/data. Accessed: July 10, 2025.

2.5 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 historical resource pursuant to Section 15064.5?
b) Cause a substantial adverse change in the significance of an archaeological resource pursuant to Section 15064.5?
c) Disturb any human remains, including those interred outside of formal cemeteries?

2.5.1 Discussion
CEQA requires lead agencies to determine if a project will have an adverse impact on a significant cultural resource, including historical, archaeological, and tribal cultural resources (Public Resources Code Sections 21084, 21084.1, 21083.2). The agency must first determine if a resource is historically significant, then determine if the project would cause a “substantial adverse change” in its significance (Public Resource Code Section 21068, State CEQA Guidelines Section 15382).

According to the State CEQA Guidelines, a resource is considered historically significant if it 1) is listed in or has been determined eligible for listing in the California Register of Historical Resources (CRHR); 2) is included in a local register of historical resources, as defined in Public Resources Code Section 5020.l(k); 3) has been identified as significant in a historical resources survey, as defined in Public Resources Code Section 5024.1 (g); or 4) is determined to be historically significant by the CEQA lead agency (California Code of Regulations Title 14, Section 15064.S[a]).

The following CRHR eligibility criteria are considered when making a significance determination:
□
□
□
IZI
IZI
IZI
□
□
□
□
□
□

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-28 February 2026 • The resource is associated with events that have made a significant contribution to the broad patterns of California's history and cultural heritage; • The resource is associated with the lives of persons important in our past; • The resource embodies the distinctive characteristics of a type, period, region, or method of construction or represents the work of an important creative individual or possesses high artistic values; or
• The resource has yielded, or may be likely to yield, information important regarding prehistory or history.

A cultural resources assessment report for the project was prepared by Cogstone (Cogstone Resource Management 2025). A search of the California Historical Resources Information System (CHRIS) was conducted by Northwest Information Center (NWIC) staff members at Sonoma State University on August 2, 2024. Included was the entire project area as well as a 0.5-mile radius.

Results of the record search indicate that 41 previous studies have been conducted within 0.5 mile of the project area. Of these, 16 cultural resources studies have been completed within the project area. The 16 cultural studies are all overview reports for multiple cities in Contra Costa County, including the city of Brentwood. No previous studies were completed within the project area that included an intensive pedestrian-level survey.

The NWIC records search also determined that no previously recorded resources were located within the project area. Four cultural resources were located within 0.5 mile of the project area. The cultural resource types include one historic archaeological site, one multicomponent site (i.e., the site is both a historic archaeological site and historic resource), and two historic built-environment resources.

In addition to the NWIC records search, a variety of sources were consulted in September 2024 to obtain information regarding the cultural context of the County. Sources included the CRHR, National Register of Historic Places (NRHP), Built-Environment Resource Directory (BERD), California Historical Landmarks (CHL), and California Points of Historical Interest (CPHI). These searches returned no results for the project area.

A Sacred Lands File (SLF) search was conducted by the Native American Heritage Commission (NAHC).

It resulted in negative results for archaeological resources. However, the NAHC provided a list of 15 Native American tribes and 33 individuals who may have information about the project area. Refer to Section 2.18, Tribal Cultural Resources, for further discussion of the consultation meetings.

On December 13, 2024, ICF archaeologist Shelby Caulder conducted an intensive pedestrian-level archaeological survey of the project area. Survey methods consisted of walking 15-meter-wide, east/west-oriented transects across the entirety of the 7.8-acre project area. Surface visibility ranged from good (75 to 80 percent) in the southern and western portions of the project area, along Business Center Drive, to poor (5 to 10 percent) in the northern portion of the project area, along Technology Way. Sediments in the southern portion of the project area consisted of a brown silty clay that appeared to have been tilled recently. Sediments in the western portion of the project area, along Business Center Drive, consisted of gravel; shrubbery was scattered throughout. Ground cover in the northern portion of the project area, along Technology Way, consisted of mostly annual grasses and forbs, which obstructed visibility. In areas with low ground visibility, areas with exposed soil due to rodent backdirt piles or other types of soil exposure were intensively inspected. No cultural resources were identified during the pedestrian-level survey.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-29 February 2026 a) Would the project cause a substantial adverse change in the significance of a historical resource pursuant to Section 15064.5?
b) Would the project cause a substantial adverse change in the significance of an archaeological resource pursuant to Section 15064.5?
The NWIC record search did not identify any historical resources in the project area, nor did searches of the NRHP, CRHR, BERD, CHL, and CPHI. As discussed above, no cultural resources were identified during the pedestrian-level survey. The project site contains no historic-age built-environment resources. As such, a built-environment survey of the project site was not conducted. However, based on information obtained during tribal consultation, the potential for subsurface pre-historic archaeological resources or tribal cultural resources being discovered during project construction is high and, therefore, a potentially significant impact. Implementation of Mitigation Measure CUL-1, CUL-2, CUL-3, and CUL-4, below, would require BMPs and other procedures in the event that unanticipated historic or pre-historic resources are encountered. Therefore, the project would have a less-than-significant impact with mitigation incorporated.

Mitigation Measure CUL-1: Environmentally Sensitive Area and Tribal Monitoring The County in consultation with the consulting Tribes, shall establish an Environmentally Sensitive Area (ESA) areas where ground disturbance would occur with potential to impact Tribal Cultural Resources. Ground disturbing activities within the ESA will be monitored by representatives of the Wilton Rancheria (Tribal Monitor). Tribal Monitors who have specific knowledge of the Tribal cultural resources in the project area shall direct construction and archaeological workers when midden soils, or other types of soils that may contain human remains, cultural materials, and sacred items are uncovered. Tribal monitors will be allowed to inspect spoils piles periodically if monitoring is reduced to spot checking. Sensitive soils that require additional attention from the Tribal Monitors will be preserved in place to the maximum extent feasible. If sensitive soils cannot be preserved in place, Wilton Rancheria will be notified, and tribal monitors will be allowed to thoroughly inspect the soils. If there are any findings of significance within the soils, the County and Wilton Rancheria will coordinate next steps. A lock box shall be kept on site before the start of work in case storage of isolated finds is necessary.

Mitigation Measure CUL-2: Cultural Awareness Training
Contractor shall be notified of the possibility of encountering historic or archaeological materials during ground-disturbing activities. A standard inadvertent discovery clause will be included in every construction contract to inform Contractors of requirements during construction.

Prior to the initiation of any grading or construction activities, a Cultural Awareness Training (CAT) training shall be provided to all construction personnel with an overview of applicable laws, Project mitigation measures, and procedures to be followed with regards to historical, archaeological, and Tribal cultural resources that may be encountered over the course of the project. The CAT will be given to any new personnel that is brought onto the project. The CAT will be provided by a representative(s) from the consulting Tribes or a representative(s) approved by the consulting Tribes who have completed CATtraining. The program will underscore the requirement for confidentiality and culturally appropriate treatment of any finds of significance to the Tribes.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-30 February 2026 Mitigation Measure CUL-3: Procedures for Inadvertent Discovery of Unanticipated Historic Resources or Tribal Cultural Resources
Procedures for discovery include:
• If potential archaeological or Tribal cultural resources materials are uncovered during construction, the Contractor shall cease all ground disturbing activities immediately within a 100-foot radius of the find and the find must be evaluated for eligibility for listing in the CRHR and NRHP. The Contractor shall immediately notify the County Resident Engineer or their designated representative to request an archaeologist who meets the Secretary of the Interior's Standards for Archaeology and the Native American Tribe(s) that have requested consultation and/or demonstrated interest in the project site, Wilton Rancheria and Confederated Villages of Lisjan Nation, to assess the nature and significance of the find under CEQA and/or the Tribe. The archaeologist shall stake the area of discovery, placing stakes no more than 10 feet apart, forming a circle having a radius of no less than 100 feet from the point of discovery.
• If the finding(s) is not determined to be potentially significant, work may resume. • If the finding(s) is determined to be potentially significant, the archaeologist in consultation with the Tribal representatives shall develop a mitigation plan outlining management of the resource, analysis, reporting of the find, and curation or reburial of cultural items. The plan shall be implemented by the County in accordance with state guidelines and in consultation with the consulting Tribes. The mitigation plan shall include avoidance of the resource or, if avoidance of the resource is not feasible, the plan shall outline appropriate treatment of the resource in coordination with the consulting Tribes and a qualified archaeologist. Examples of appropriate avoidance and mitigation for the Tribal cultural resources include, but are not limited to, protecting the cultural character and integrity of the resources, protecting traditional use of the resources, protecting the confidentiality of the resources, heritage recovery, processing materials for reburial, minimizing handling of cultural objects, leaving objects in place within the landscape, construction monitoring of any further activities by a Tribal representative, and/or returning the objects to a location that will be set aside within the Project area or area agreed upon with consulting Tribes where they will be protected in perpetuity not be subject to future impacts such as development. Preservation in place (i.e., avoidance) is typically the preferred manner of treatment of Tribal resources and cultural items. Tribal Cultural Resources shall not be permanently curated, unless specifically requested by the Tribe. Work may resume according to the recommendations in the mitigation plan.
• Any previously undiscovered resources found during construction within the Project Site shall be recorded on appropriate California Department of Parks and Recreation (DPR) 523 forms. These forms shall be submitted to Contra Costa County Department of Conservation and Development, and the Northwest Information Center (NWIC), as required. County will follow an unanticipated discovery plan developed with the Tribe for curation or reburial of resources.

Mitigation Measure CUL-4: Communication Protocols for Tribal Monitoring The contractor shall develop a set of communication protocols, to the satisfaction of the County and Wilton Rancheria, to identify all points of contact and to ensure that tribes are notified when the applicant will proceed with authorized construction activities. Points of contact will be

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-31 February 2026 established for the applicant, construction supervisor, monitoring tribes, and County archaeologist, and the contact numbers and email addresses must be documented and shared among all parties. Points of contact are responsible for identifying backup representatives in the event they are unable to perform due to an absence or other reasons.

The contractor shall provide advanced notice of the anticipated work schedule involving earthmoving activities of the project within a minimum of ten (10) business days prior to the specified work commencing.
c) Would the project disturb any human remains, including those interred outside of formal cemeteries? No human remains or cultural resources were identified from the NWIC record search, or other research, or during the pedestrian-level survey of the project area. In addition, no formal cemeteries are present within or adjacent to the project site. However, project construction could discover human remains if present within the project site, a potentially significant impact. Implementation of Mitigation Measure CUL-5, below, details the course of action if human remains are discovered.

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

Mitigation Measure CUL-5: Stop Work and Notification Procedures for Human Remains In the event of the accidental discovery or recognition of any human remains, there shall be no further excavation or disturbance within 100 feet of the remains. The Contra Costa County Coroner will be contacted immediately to determine whether the remains are Native American and if an investigation of the cause of death is required. At the same time, an archaeologist shall be contacted to assess the situation.

If the Coroner determines the remains may be those of a Native American, the Coroner shall contact the Native American Heritage Commission (NAHC) by telephone within 24 hours of this identification. The NAHC shall identify a Most Likely Descendant (MLD) to inspect the site and provide recommendations for the proper treatment of the remains and associated funerary objects. [Pursuant to California Health and Safety Code Section 7050] If the MLD recommend keeping ancestral remains and funerary objects in situ and protected, the County shall make every effort to follow the recommendation. If removal of ancestral remains and related funerary objects is necessary, Tribal representatives shall work with the qualified archaeologist to ensure that excavation and documentation are conducted carefully, ethically, and the ancestral remains are treated respectfully. No photography or scientific study, destructive or non-destructive, shall be conducted on ancestral human remains. No presentations or other in-person displays of data shall be done without explicit and written approval from Wilton Rancheria. The archaeologist shall prepare a report of all activities, including the recommendations of the MLD for the treatment of the human remains and any associated funerary objects. The report shall be submitted to the County, the Northwest Information Center, and the Tribe(s). [Pursuant to California Public Resources Code Section 5097.98]
The County, as the landowner, in consultation with the Tribe(s) shall provide a secure, climatecontrolled storage facility for any recovered ancestral remains until completion of the excavation process. If no such facility exists, the remains shall be secured in a lockbox on-site.

The County shall also be responsible for securing exposed but unrecovered ancestral remains during the excavation process. This may include hiring temporary security staff or covering the exposed excavation area with large metal plates that do not contact the remains.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-32 February 2026 Native American human remains and associated funerary objects shall be treated with appropriate dignity until reburial by Tribal representatives either: 1) In accordance with the recommendations of the MLD if available; or 2) In the project vicinity at a location agreed upon by the MLD and the County, where the reburial would be protected in perpetuity and would not be subject to further subsurface disturbance. The discovery is to be documented on DPR523 forms or submitted to the Native American Heritage Commission (NAHC) and otherwise kept confidential and secure to prevent any further disturbance.

2.5.2 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.

2.6 Energy
Potentially
Significant
Impact
Less than
Significant with
Mitigation
Incorporated
Less-thanSignificant
Impact No Impact
Would the project:
a) Result in potentially significant environmental impact due to the wasteful, inefficient, or unnecessary consumption of energy resources during project construction or operation? b) Conflict with or obstruct a state or local plan for renewable energy or energy efficiency?

2.6.1 Discussion
a) Would the project result in potentially significant environmental impact due to the wasteful, inefficient, or unnecessary consumption of energy resources during project construction or operation? The project would not result in the wasteful, inefficient, or unnecessary consumption of energy.

Although energy would be used during both construction and operation of the proposed project, the project would be designed to minimize its impact through compliance with regulatory standards.

The project would be constructed pursuant to Part 6 of the California Energy Code, which ensures a baseline level of energy efficiency and design. To further reduce energy consumption, the project would incorporate renewable energy sources and infrastructure, including a solar photovoltaic system to generate electricity on-site, a geothermal system to heat and cool the building, and EV supply equipment (EVSE). Furthermore, the project would be expected to achieve, at a minimum, LEED Silver certification by incorporating energy efficient designs. Therefore, the project would have a less-than-significant impact.
b) Would the project conflict with or obstruct a state or local plan for renewable energy or energy efficiency?
The project would not conflict with or obstruct a state or local plan for renewable energy or energy efficiency. Locally, although the City of Brentwood is in the process of creating a climate action plan, the County has adopted the 2024 Climate Action and Adaptation Plan (CAAP) as part of the Envision Contra Costa County 2045 General Plan, the County’s comprehensive update to its general plan,

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-33 February 2026 zoning code, and climate action plan (County 2024). The CAAP includes goals for expanding renewable energy use and increasing energy efficiency in buildings and infrastructure. The project’s design and operational features, such as a solar photovoltaic system to generate electricity on-site, a geothermal system to heat and cool the building, and EVSE, would be consistent with the objectives.

At the state level, the project would support the framework laid out in CARB’s 2022 scoping plan update, which emphasizes decarbonizing the electricity sector through efficient energy use and replacing fossil-fueled generation with renewable and zero-carbon resources. The project also support the goals of Senate Bill (SB) 100, which requires renewable and zero-carbon resources to supply 90 percent of all retail electricity sales by 2035 and 95 percent of all retail electricity sales by 2040 (CARB 2022). As mentioned above, the project would include a rooftop photovoltaic system to supply on-site renewable energy, a geothermal system to heat and cool the building, LEED Silver certification, and EVSE. Given the project’s incorporation of renewable energy infrastructure and compliance with state and County climate planning efforts, the project would have a less-thansignificant impact.

2.6.2 Sources of Information
California Air Resources Board. 2022. 2022 Scoping Plan for Achieving Carbon Neutrality. November.

Available: https://ww2.arb.ca.gov/sites/default/files/2022-12/2022-sp_1.pdf.

Contra Costa County. 2024. Contra Costa County 2024 Climate Action and Adaptation Plan. Adopted November 5, 2024. Available: https://www.contracosta.ca.gov/DocumentCenter/View/84967/ Contra-Costa-County-2024-Climate-Action-and-Adaptation-Plan-PDF?bidId=.

2.7 Geology/Soils
Potentially
Significant
Impact
Less than
Significant with
Mitigation
Incorporated
Less-thanSignificant
Impact No Impact
Would the project:
a) Directly or indirectly cause potential substantial adverse effects, including the risk of loss, injury, or death involving:
i) Rupture of a known earthquake fault, as delineated on the most recent Alquist-Priolo Earthquake Fault Zoning Map
issued by the State Geologist for the area or based on
other substantial evidence of a known fault? Refer to
Division of Mines and Geology Special Publication 42.
ii) Strong seismic ground shaking?
iii) Seismically related ground failure, including liquefaction? iv) Landslides?
b) Result in substantial soil erosion or the loss of topsoil? c) Be located on a geologic unit or soil that is unstable or that would become unstable as a result of the project and
potentially result in on- or off-site landslide, lateral spreading, subsidence, liquefaction, or collapse?
d) Be located on expansive soil, as defined in Table 18-1-B of the Uniform Building Code (1994), creating substantial direct or indirect risks to life or property?

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-34 February 2026 Potentially
Significant
Impact
Less than
Significant with
Mitigation
Incorporated
Less-thanSignificant
Impact No Impact
Would the project:
e) Have soils incapable of adequately supporting the use of septic tanks or alternative waste water disposal systems where sewers are not available for the disposal of wastewater? f) Directly or indirectly destroy a unique paleontological resource or site or unique geological feature?

2.7.1 Discussion
a) Directly or indirectly cause potential substantial adverse effects, including the risk of loss, injury, or death involving:
i) Rupture of a known earthquake fault, as delineated on the most recent Alquist-Priolo Earthquake Fault Zoning Map issued by the State Geologist for the area or based on other substantial evidence of a known fault? Refer to Division of Mines and Geology Special Publication 42.

The Alquist-Priolo Earthquake Fault Zone Act of 1972 regulates development near active faults for the purpose of preventing surface fault rupture hazards at structures for human occupancy. The project site is not mapped within an Alquist-Priolo Fault Zone or within a currently designated California Earthquake Fault Zone. According to the geotechnical report prepared by ENGEO, no known faults have been mapped on the site (ENGEO 2025). Because no active faults cross the project site, the project would not exacerbate known risks of fault rupture or exacerbate an existing fault rupture risk. Therefore, the project would have no impact. ii) Strong seismic ground shaking?
The project site is in a seismically active region. Small earthquakes occur every year in the San Francisco Bay Area. However, large earthquakes have been recorded and can be expected to occur in the future (ENGEO 2025). The project would not involve any activity, such as groundwater injection, that would exacerbate seismicity. Therefore, the project would have no impact. iii) Seismically related ground failure, including liquefaction? Research and historical data indicate that soil liquefaction generally occurs in saturated, loose granular soil (primarily fine to medium-grained, clean poorly graded sand deposits) during or after strong seismic ground shaking. It is typified by a loss of shear strength in the affected soil layer, thereby causing the soil to flow as a liquid. Liquefaction increases with the duration and magnitude of cyclic loading. However, because of the higher intergranular pressure of the soil at greater depths, the potential for liquefaction is generally limited to the upper 40 feet of the soil. Potential hazards associated with liquefaction below or near a structure include loss of foundation support, lateral spreading, sand boils, and areal and differential settlement.

The site is within a California Seismic Hazard Zone (California Department of Conservation 2018) and may be susceptible to liquefaction. Therefore, a comprehensive evaluation of the liquefaction hazard was required. A geotechnical investigation analyzed soil conditions on the project site and found that the subsurface materials encountered in the borings consisted of lean clay (with and without sand) and fat clay with interbedded layers of coarse-grained material at depth (ENGEO □
□
□ □
□ □

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-35 February 2026 2025). Based on the geotechnical report, it was determined that a zone of potentially liquefiable soil is generally located between 25 and 28 feet below ground surface (bgs) and 34 to 42 feet bgs within groundwater observation locations (i.e., cone penetration tests [CPTs] 1-CPT2, 1-CPT3, 1-CPT4, and 1-CPT6). Silty sand is present below the groundwater table in some regions of the site, as observed at 1-CPT2 and 1-CPT3. Given the relative thickness of non-liquefiable surface soil and the potentially liquefiable soil, the risk of surface disruption is low to negligible. Because the project site is relatively low, a nearby free-face is not present. The risk of liquefaction is low, and the risk of lateral spreading is judged to be very low. The project would not exacerbate liquefaction risks because liquefiable soil would be replaced prior to construction to ensure a steady foundation. Therefore, the project would have a less-than-significant impact.
iv) Landslides?
According to Figure HS-18B, Landslide Hazards, of the County General Plan, the project site is not within a potential landslide area (County 2024). The project site is in a generally flat area. There are no nearby slopes that would be vulnerable to landslides. The project would not create substantial slopes and therefore would not exacerbate existing conditions. Therefore, the project would have no impact.
b) Result in substantial soil erosion or the loss of topsoil? The modified grades associated with the completed project would result in negligible changes in topography. Construction of the project would temporarily increase the exposure of soils to stormwater runoff and wind erosion because of grading and excavation. However, standard erosion control BMPs would be implemented during construction to minimize potential impacts. A Stormwater Pollution Prevention Plan (SWPPP) would be prepared consistent with the Statewide Construction General Permit (Order No. 2022-0057-DWQ). See Section 2.10, Hydrology/Water Quality, for more details about the SWPPP. Therefore, the project would have a less-thansignificant impact. c) Be located on a geologic unit or soil that is unstable or that would become unstable as a result of the project and potentially result in on- or off-site landslide, lateral spreading, subsidence, liquefaction, or collapse?
As noted above, the project site is not located in an area that is subject to landslides. The geotechnical investigation determined that the risk of liquefaction is very low, as is lateral spreading and lurch cracking. The project would not exacerbate existing conditions. Therefore, the project would have no impact.
d) Be located on expansive soil, as defined in Table 18-1-B of the Uniform Building Code (1994), creating substantial direct or indirect risks to life or property? The Design-Level Geotechnical Exploration report (ENGEO 2025) identified potentially expansive lean clay, lean clay with sand, and fat clay near the surface of the site. Laboratory testing indicates that the soil exhibits moderate to high shrink/swell potential, with variations in moisture content.

Expansive soil changes in volume with changes in moisture. It can shrink or swell and cause heaving and cracking in slabs, pavement, and structures on shallow foundations. The geotechnical report recommended that the upper 18 inches of the building pad, extending at least 5 feet laterally beyond building areas, be underlain by fill with relatively low expansion potential (plasticity index [PI] less

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-36 February 2026 than 20). The report also recommended that the project assume a lime concentration of 4 percent by dry unit weight of mixed soil to appropriately reduce the expansive nature of the native soil.

Prior to the issuance of a building permit, the County Building Department will review the construction, foundation, and civil plans for consistency with the geotechnical recommendations found in the Design-Level Geotechnical Exploration report (ENGEO 2025) to ensure that the construction recommendations are included in construction plans and designs. Therefore, the project would have a less-than-significant impact.
e) Have soils incapable of adequately supporting the use of septic tanks or alternative waste water disposal systems where sewers are not available for the disposal of wastewater? A new sanitary sewer system would be constructed for the project. A septic tank or alternative wastewater disposal system would not be required. Therefore, the project would have no impact. f) Directly or indirectly destroy a unique paleontological resource or site or unique geological feature? The project site is underlain by very young Holocene surficial sediments consisting of Alluvial Loam of Valley Areas (QI) and Alluvial Clay of Valley Areas (Qc) (ENGEO 2025). Although Holocene-age sediments are typically too young to contain fossilized material, they may overlie older deposits, and suitable conditions exist at the project site for the possibility of fossils to exist at depths of 5 to 10 feet below ground surface (De Novo Planning Group 2014). The maximum depth of excavation for the project is up to 400 feet for the proposed geothermal system; therefore, the project is likely to encounter paleontological resources if present. In addition, as the exact depth of potentially underlying older deposits cannot be known before excavation, there is the potential for subsurface paleontological resources to be discovered during project construction, a potentially significant impact. Implementation of Mitigation Measure GEO-1, below, would require procedures in the event that unanticipated paleontological resources are encountered. Therefore, the project would have a less-than-significant impact with mitigation incorporated.

Mitigation Measure GE0-1: Procedures for Paleontological Resources Contractor(s) shall be notified of the possibility of encountering paleontological materials during ground-disturbing activities. A standard inadvertent discovery clause will be included in every construction contract to inform contractors of requirements during construction.

Implement the following measures if potential unanticipated paleontological resources are discovered during project construction.
1) Contractor will be educated on the types of materials that may be encountered. 2) If an inadvertent discovery is made, the contractor will cease all ground-disturbing activities in the area of discovery.
3) Contractor will immediately notify the County who will then request a qualified paleontologist to evaluate the finding(s).
4) If the finding(s) is determined to be potentially significant, the paleontologist will develop a research design and treatment plan outlining management of the resource, analysis, and reporting of the find.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-37 February 2026

2.7.2 Sources of Information
California Department of Conservation 2018. EQ Zapp: California Earthquake Hazards Zone Application Earthquake Zones of Required Investigation. California Geological Survey. Available:
https://maps.conservation.ca.gov/cgs/informationwarehouse/eqzapp/.

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.

De Novo Planning Group. 2014. Public Draft Environmental Impact Report for the 2014 Brentwood General Plan Update. Available: https://www.brentwoodca.gov/home/ showpublisheddocument/2832/637794835332370000.

ENGEO, Inc. 2025. Design-Level Geotechnical Exploration. Revised: March 28, 2025.

2.8 Greenhouse Gas Emissions
Potentially
Significant
Impact
Less than
Significant with
Mitigation
Incorporated
Less-thanSignificant
Impact No Impact
Would the project:
a) Generate greenhouse gas emissions. either directly or indirectly, that may have a significant impact on the
environment?
b) Conflict with an applicable plan, policy, or regulation adopted for the purpose of reducing the emissions of greenhouse gases?

2.8.1 Discussion
Setting
Human activities that generate GHGs increase the amount of infrared radiation absorbed by the atmosphere, thereby enhancing the greenhouse effect and amplifying the warming of Earth.

Increases in fossil fuel combustion and deforestation have exponentially increased concentrations of GHGs in the atmosphere since the Industrial Revolution (Intergovernmental Panel on Climate Change [IPCC] 2007). Rising atmospheric concentrations of GHGs, in excess of natural levels, have resulted in increasing global surface temperatures—a process commonly referred to as global warming. Higher global surface temperatures have, in turn, resulted in changes to Earth’s climate system, including increases in ocean temperature and acidity, reduced sea ice, variable precipitation, and increases in the frequency and intensity of extreme weather events (IPCC 2018). Large-scale changes to Earth’s system are collectively referred to as climate change.

The principle anthropogenic (human-made) GHGs are carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and fluorinated compounds, including sulfur hexafluoride, hydrofluorocarbons (HFCs), and perfluorocarbons. The primary GHGs that would be emitted by project-related construction and operations include CO2, CH4, and N2O. The principal characteristics of these pollutants are discussed below.

ISi ISi

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-38 February 2026 • Carbon dioxide enters the atmosphere through the combustion of fossil fuel (i.e., oil, natural gas, coal), solid waste decomposition, plant and animal respiration, and chemical reactions (e.g., from manufacturing cement). CO2 is also removed from the atmosphere, or sequestered, when it is absorbed by plants as part of the biological carbon cycle. • Methane is emitted during the production and transport of coal, natural gas, and oil. CH4 emissions also result from livestock and agricultural practices as well as the anaerobic decay of organic waste in municipal solid waste landfills.
• Nitrous oxide is emitted by agricultural and industrial activities as well as the combustion of fossil fuels and solid waste.

Regulatory Setting
California has adopted statewide legislation to address various aspects of climate change and implement GHG emissions mitigation. Much of this legislation establishes a broad framework for the state’s long-term GHG reduction and climate change adaptation program. Of particular importance are SB 32 and AB 1279, which outline the state’s GHG reduction goals (i.e., achieving a 40 percent reduction in GHG emissions by 2030 [relative to 1990 emissions levels] and net-zero GHG emissions no later than 2045 (i.e., reach a balance between GHGs emitted and removed from the atmosphere). AB 1279 also mandates an 85 percent reduction in statewide GHG emissions (from 1990 levels) by 2045. The 2017 climate change scoping plan and the 2022 scoping plan update provide frameworks for achieving the 2030 and 2045 reduction targets, respectively, by leveraging and enhancing many of the efforts and programs already adopted by the state (CARB 2017 and 2022a).

Recent actions by President Donald Trump have significantly altered the federal climate policy landscape. On January 20, 2025, President Trump signed Executive Order 14154, which includes pausing the disbursement of funds appropriated through the Inflation Reduction Act (2022) and targeting incentives for EVs and other clean energy technologies. Although some of President Biden's policies remain, these new executive orders represent a shift away from the previous administration's focus on reducing GHG emissions and increasing climate resiliency.

The sections that follow describe regional and local regulations relevant to the project.

Metropolitan Transportation Commission
The Metropolitan Transportation Commission (MTC) is the metropolitan planning organization for the nine counties that make up the Bay Area and SFBAAB, including Contra Costa County. In October 2021, MTC and the Association of Bay Area Governments (ABAG) adopted Plan Bay Area 2050, the latest regional transportation plan/sustainable communities strategy (RTP/SCS) for the SFBAAB. Plan Bay Area 2050 incorporates emission reduction targets that were updated by CARB in 2018 pursuant to SB 375 and carries forward many of the development and funding strategies of earlier plans (MTC/ABAG 2021a).

Air District
The Air District is the primary agency responsible for managing air quality in the Bay Area, including Contra Costa County. It provides recommended methods for analyzing project-related GHGs in CEQA reviews. In April 2023, the Air District published the most recent version of its Air District CEQA Guidelines, which offer direction for evaluating plan- and project-level air quality and climate

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-39 February 2026 impacts. The guidelines also outline best practices for centering environmental justice, health, and equity thresholds when evaluating a project’s impact on air quality (Air District 2023). Appendix B of the guidelines, CEQA Thresholds for Evaluating the Significance of Climate Impacts, provides substantial evidence in support of the Air District’s updated GHG thresholds and recommendations for assessing project-level climate impacts. This analysis was prepared in accordance with the guidance and recommendations outlined in the Air District CEQA Guidelines.

Construction GHG Emissions
The Air District CEQA Guidelines do not identify a GHG emissions threshold for construction-related emissions (Air District 2023). Nonetheless, the Air District CEQA Guidelines recommend the quantification and disclosure of construction-related GHG emissions. Even though the significance of construction GHG emissions has not been determined, the Air District CEQA Guidelines provide BMPs that projects should incorporate to reduce construction-related GHG emissions (Air District 2023).

Operational GHG Emissions
According to the Air District CEQA Guidelines, the Air District recommends focusing the evaluation of land use projects on contributions to the state’s efforts to meet long-term climate goals. If a project would contribute its “fair share”5 of what would be required to achieve long-term climate goals, then a reviewing agency can find that the impact would not be significant because the project would help to solve the problem of global climate change (Air District 2023). Applying this approach, the Air District has found that a new land use development project being built today would need to incorporate the design elements provided in Table 2-7 to do its fair share toward meeting the SB 32 target for 2030 and the goal of carbon neutrality by 2045. 5 The Air District defines “fair share” as the design elements that need to be incorporated into a project to lay the foundation for achieving carbon neutrality by 2045. These design elements are elements that the project has influence or control over. For example, becoming carbon neutral by 2045 will require California’s electrical power generators to shift to 100 percent carbon-free energy resources, which is not something that can be controlled through the design of new land use projects and would not be a part of a project’s fair share. Other sources that would not be part of the “fair share” are the vehicle fleet mix or indirect off-site emissions (e.g., methane emissions from wastewater or solid waste).

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-40 February 2026 Table 2-7. Air District Greenhouse Gas Thresholds for Land Use Projects Thresholds for Land Use Projects (Must Include A or B)
A. Projects must include, at a minimum, the following project design elements:

1. Buildings
a. The project would not include natural gas appliances or natural gas plumbing (in both residential and nonresidential development).
b. The project would not result in any wasteful, inefficient, or unnecessary electrical usage, as determined by the analysis required under Section 21100(b)(3) of the CEQA statute and Section 15126.2(b) of the State CEQA Guidelines.

2. Transportation
a. Achieve compliance with EV requirements in the most recently adopted version of the California Green Building Standards Code (CALGreen), Tier 2. b. Achieve a reduction in project-generated vehicle miles traveled (VMT) to a level below the regional average, consistent with the current version of the California Climate Change Scoping Plan (currently, 15 percent) or meet a locally adopted SB 743 VMT target, reflecting the recommendations provided in the Governor’s Office of Planning and Research’s Technical Advisory on Evaluating Transportation Impacts in CEQA:
i. Residential projects: 15 percent below existing VMT per capita ii. Office projects: 15 percent below existing VMT per employee iii. Retail projects: no net increase in existing VMT
B. Projects must be consistent with a local GHG reduction strategy that meets the criteria under State CEQA Guidelines Section 15183.5(b).

Source: Air District 2023.

If a project is designed and built to incorporate the design elements listed in Table 2-7 (Threshold Option A) or consistent with a local GHG reduction strategy under Section 15183.5(b) of the State CEQA Guidelines (Threshold Option B), then it would contribute its portion of what is necessary to achieve California’s long-term climate goals—its fair share—and would not make a cumulatively considerable contribution to global climate change. If the project does not incorporate these design elements and is not consistent with a local GHG reduction strategy, then it should be found to have a significant climate impact because it would hinder the state’s efforts to address climate change. This analysis evaluates the project’s consistency with the County’s CAAP (Threshold Option B) to determine the significance of the project’s GHG emissions.

Contra Costa County
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 2024a). It provides comprehensive policy direction to support clean air, promote community and environmental health equitably, and reduce GHG emissions in alignment with state and local climate goals. As part of this framework, the General Plan identifies the following goal areas, which form the foundation for specific policies and actions aimed at achieving these objectives:
• Goal HS-1: Air quality that supports community and environmental health. • Goal HS-2: Healthy air quality for all communities, so no community bears the disproportionate burden of environmental hazards and health risks.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-41 February 2026 • Goal HS-3: Communities that reduce existing and anticipated GHG emissions in support of statewide carbon neutrality goals and other GHG reduction targets. • Goal HS-4: Resilient communities that are prepared for, responsive to, and able to recover from hazards created or worsened by climate change.

The project’s consistency with the County General Plan is evaluated in Section 2.11, Land Use/Planning.

Contra Costa County Climate Action and Adaptation Plan 2024 Update Contra Costa County adopted the 2024 CAAP as part of the Envision Contra Costa 2045 General Plan, the County’s comprehensive update to its general plan, zoning code, and climate action plan (Contra Costa County 2024b). The 2024 CAAP builds upon the County’s 2015 climate action plan and establishes a strategic framework for both adapting to climate change and reducing GHG emissions in alignment with California’s statewide goal of achieving net-zero emissions by 2045.

In coordination with existing and planned state, regional, and local initiatives, the 2024 CAAP introduces a suite of new GHG reduction strategies, aimed at helping the County meet its GHG reduction targets of 658,700 metric tons of CO₂e by 2030 and 164,680 metric tons of CO₂e by 2045.

These strategies are organized into five key focus areas:

Clean and Efficient Built Environment (BE)
• BE-1: Require and incentivize new buildings and additions built in unincorporated Contra Costa County to be low carbon or carbon neutral.
• BE-2: Reduce emissions from existing buildings through energy efficiency upgrades and electrification.
• BE-3: Increase renewable energy generation and storage in buildings. • BE-4: Promote sustainable and low-carbon building materials and construction practices. • BE-5: Improve energy efficiency and reduce emissions from County facilities and operations.

No-Waste Contra Costa (NW)
• NW-1: Reduce organic waste sent to landfill through diversion, composting, and food recovery. • NW-2: Reduce construction and demolition waste and promote material reuse. • NW-3: Promote circular economy practices and reduce consumption of high-emissions goods.

Reduce Water Use and Increase Drought Resilience (DR)
• DR-1: Reduce potable water use in buildings and landscapes. • DR-2: Increase use of recycled water and greywater systems. • DR-3: Promote water-efficient landscaping and irrigation practices.

Clean Transportation Network (CT)
• CT-1: Reduce VMT through land use planning and transportation demand management. • CT-2: Expand and improve public transit options.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-42 February 2026 • CT-3: Increase active transportation infrastructure and safety. • CT-4: Accelerate the transition to zero-emission vehicles (ZEVs). • CT-5: Expand EV charging infrastructure and support ZEV adoption.

Climate Equity (CE)
• CE-1: Ensure equitable access to climate programs and benefits. • CE-2: Prioritize investments in communities most vulnerable to climate impacts. • CE-3: Support workforce development and job training in green industries.

City of Brentwood
City of Brentwood General Plan
The current City General Plan, adopted in 2014, includes goals and policies related to air quality and emission reductions (City of Brentwood 2014). These goals and policies include continuing to improve air quality by reducing emissions from construction activities, coordinating air quality planning efforts locally and regionally, and focusing improvements on non-motorized modes of transportation. The project’s consistency with the City General Plan is evaluated in Section 2.11, Land Use/Planning.

The City’s General Plan includes the following goals and policies associated with GHG emissions:

Goal COS 8: Reduce air pollutants and GHG emissions
Policy COS 8-4: Encourage new development or significant remodels to install fireplaces, wood stoves, and/or heaters that meet Air District standards.

Policy COS 8-5: Continue to require all construction projects and ground-disturbing activities to implement Air District dust control and abatement measures.

Policy COS 8-6: Support the development and implementation of a GHG reduction plan, or climate action plan, that addresses and reduces GHG emissions associated with community operations, including, but not limited to, mobile sources (vehicle traffic), energy consumption, and solid waste.

Policy COS 8-7: Coordinate with Contra Costa County and nearby cities to implement regional GHG reduction plans and consolidate efforts to reduce GHGs throughout the county.

Policy COS 8-8: Encourage local businesses and industries to engage in voluntary efforts to reduce GHG emissions and energy consumption.

Policy COS 8-9: Preserve, protect, and enhance, as appropriate, the city’s carbon sequestration resources, also referred to as “carbon sinks,” to improve air quality and reduce net carbon emissions.

Policy COS 8-10: Encourage public transit, ridesharing and van pooling, shortened and combined motor vehicle trips to work and services, use of bicycles, and walking. Minimize single-passenger motor vehicle use.

Policy COS 8-11: Encourage new construction to incorporate passive solar features.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-43 February 2026 a) Would the project generate greenhouse gas emissions, either directly or indirectly, that may have a significant impact on the environment?
Construction
Construction activities associated with the project would result in short-term GHG emissions, primarily from the combustion of fuel in off-road equipment, construction employee vehicles, vendor trucks, and haul trucks. In addition, electricity use during construction would contribute to indirect GHG emissions. The magnitude of daily emissions would vary, depending on the construction phase, type of equipment in use, daily work activities, and number of employees onsite.

Short-term GHG emissions generated by project construction were calculated with use of CalEEMod, version 2022.1, which relies on vehicle emissions factors from CARB’s EMFAC2021, as recommended by the Air District and other air districts in California (CAPCOA 2022). Modeling was based on default values from CalEEMod, which are generated by the model according to a project’s location and land use type and project-specific information where available, including building type and size, expected construction phase duration, demolition and earthwork, and the area to be graded or paved. Detailed model assumptions, inputs, and output files for the calculations are provided in Attachment A. Based on the modeling, it is estimated that project-related construction would generate approximately 866 metric tons (MT) of carbon dioxide equivalent (CO2e) over the construction period (2026–2027). GHG emissions from equipment and vehicle exhaust would be equal to approximately 811 MT of CO2e, while the remaining emissions, 55 MT of CO2e, would be from the use of electricity during construction. In addition, the Air District recommends incorporation of BMPs to reduce GHG emissions during construction, as feasible and applicable. The project contractors would implement BMPs recommended by the Air District, as shown in Table 6-1 of the State CEQA Guidelines, to reduce GHG emissions during construction, as feasible and applicable (Air District 2023). Examples of the BMPs that may be implemented include, but are not limited to, the following:
• Use zero-emission and hybrid-powered equipment to the greatest extent possible. • Use locally sourced or recycled materials for construction materials (goal of at least 20 percent, based on costs for building materials and volume for roadway, parking lot, sidewalk, and curb materials). Wood products used should be certified through a sustainable forestry program. • Recycle or salvage nonhazardous construction and demolition debris, with a goal of recycling at least 15 percent more by weight than the diversion requirement in Title 24.

As noted above, the Air District has not established a quantitative threshold for assessing construction GHG emissions because emissions from construction are temporary and variable (Air District 2023). Therefore, the determination of the significance of the project’s GHG impact is based on the potential for project operation to generate GHG emissions that may have a significant impact on the environment.

Operation
The project is expected to be fully operational by 2027. Operational activities would generate longterm GHG emissions, primarily from motor vehicles traveling to and from the project site, the use of landscaping equipment, electricity consumption, water usage, and solid waste generation. These

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-44 February 2026 activities would generate the highest level of operational emissions in the first year of full buildout (2027).6 Table 2-8 shows estimated annual GHG emissions associated with full buildout in 2027.

Table 2-8. Operational Greenhouse Gas Emissions by Emissions Source for 2027 Emissions Source Annual GHG Emissionsa (MT of CO2e)
Mobile sources 1,545
Area sources 2
Energy use 354
Water use 47
Solid waste generation 214
Refrigerants < 1
Total Operational GHG Emissions 2,162
Source: Attachment A.

Notes:
a. Values may not sum due to rounding.

MT of CO2e = metric tons of carbon dioxide equivalent
As shown in Table 2-8, the project would generate approximately 2,162 MT of CO2e during its first year of operation (full buildout). Most of the annual GHG emissions, approximately 71 percent, would be from mobile sources (e.g., County workers, visitors, and delivery drivers traveling to and from the site). Electricity consumed and waste generated at the site would represent 16 percent and 10 percent of total annual emissions, respectively. The remaining sources of emissions (i.e., area sources, water use, refrigerants, stationary sources) represent a combined 3 percent of total annual emissions. Although these emission estimates are not directly used to determine significance under CEQA, they are included here to provide a fully comprehensive assessment of the project’s impacts.

Under the Air District’s Land Use Threshold Option B, projects must demonstrate consistency with a local GHG reduction strategy. To address this requirement, the following discussion evaluates the project’s alignment with the County CAAP. Table 2-9 evaluates the project’s consistency with the 2024 CAAP climate action strategies to determine if the project would generate GHG emissions, either directly or indirectly, that may have a significant impact on the environment.

Table 2-9. Project Consistency with the County’s 2024 CAAP Climate Action Strategies Climate Action Strategy Project Consistency
BE-1: Require and incentivize new
buildings and additions built in
unincorporated Contra Costa County to be
low carbon or carbon neutral.

Consistent. The project would be built to LEED Silver
standards. The project would be all electric, and no
natural gas infrastructure would be constructed.

BE-2: Retrofit existing buildings and
facilities in the unincorporated county,
and County infrastructure, to reduce
energy use and convert to low-carbon or
carbon-free fuels.

Not applicable. The project involves a new building; it would not retrofit an existing building.
6 Emissions in subsequent years would continually decrease as the statewide vehicle fleet transitions to newer lowcarbon-emitting vehicles and electric power is generated from more renewable sources; thus, 2027 represents a worst-case year.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-45 February 2026 Climate Action Strategy Project Consistency
BE-3: Increase the amount of electricity
used and generated from renewable
sources in the county.

Consistent. The project would include a solar
photovoltaic system and a geothermal system to heat and cool the building.

NW-1: Increase composting of organic
waste.

Consistent. The project would include green waste bins
and participate in a composting program managed by the
County, providing garbage, yard waste, and recycling
collection services to the project site.

NW-2: Reduce waste from County
operations.

Consistent. The project would be served by the County,
which implements three-stream recycling (i.e., trash,
recycling, and organic waste).

NW-3: Increase community-wide recycling
and waste minimization programs.

Not applicable. This measure involves expanding waste
minimization programs, which is not within the scope of a County services center.

NW-4: Reduce emissions from landfill gas. Not applicable. This measure applies to the operations of County-owned landfills, which is not within the scope of a County services center.

DR-1: Reduce indoor and outdoor water
use.

Consistent. The project would be built to LEED Silver
standards, which require drought-tolerant landscaping
and devices.

DR-2: Ensure sustainable and diverse
water supplies.

Not applicable. This measure involves decision-making
with respect to water supplies, which is not within the scope of a County services center.

TR-1: Improve the viability of walking,
biking, zero-emission commuting, and
using public transit for travel within, to,
and from the county.

Consistent. The project would include 22 long-term and
36 short-term bicycle parking spaces, thereby supporting active transportation and enhancing the viability of
biking as a commuting option for the staff and visitors.

The project site is also less than 0.25 mile from the
Brentwood Boulevard and Sand Creek Road bus stop,
which is served by Tri Delta Transit’s 300X Brentwood
Park & Ride and the Antioch BART line.

TR-2: Increase the use of zero-emission
vehicles. Transition to a zero-emission
County fleet by 2035 and a community
fleet that is at least 50 percent zeroemission by 2030.

Consistent. The project would include 108 EV-capable
spaces, with 82 Type 2 EV chargers and four directcurrent fast charging stations. Thus, the project would allow workers and visitors to charge their vehicles,
facilitating the transition to a zero-emission fleet in the county.

NI-1: Protect against and adapt to changes
in sea levels and other shoreline flooding
conditions.

Not applicable. The project site is not near the shoreline and thus less vulnerable to sea-level rise.

NI-2: Protect against and adapt to
increases in the frequency and intensity of
wildfire events.

Not applicable. The project’s purpose is to provide
County services rather than protect against increases in the frequency and intensity of wildfire events.

NI-3: Establish and maintain community
resilience hubs.

Not applicable. The project’s purpose is to provide a
County services center rather than a community
resilience hub.

NI-4: Sequester carbon on natural and
working lands in Contra Costa County.

Not applicable. Sequestration of carbon on natural and
working lands is not within the scope of a County
services center. The project site is a flat, grassy
undeveloped lot with no trees that sequester carbon.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-46 February 2026 Climate Action Strategy Project Consistency
NI-5: Minimize heat-island effects through
the use of cool roofs, green infrastructure,
tree canopies, cool paint and pavement,
and other emerging strategies.

Consistent. The project would result in tree planting,
creating a new tree canopy where one does not currently exist.

NI-6: Protect communities against
additional hazards created or exacerbated
by climate change.

Not applicable. Protection against hazards created or
exacerbated by climate change is not within the scope of a County services center.

CE-1: Provide access to affordable, clean,
safe, and healthy housing and jobs.

Consistent. Although the project would not provide
housing, it would make valuable services more accessible to community members, who may be more likely to
secure employment with access to the services.

CE-2: Invest in solutions to support
climate equity.

Consistent. By placing a new services center in an area where no such facility exists, the project would result in County services being more accessible to residents,
including vulnerable populations who may be
disproportionately affected by climate-related hazards.

CE-3: Increase access to parks and open
space.

Consistent. Although the project is a County services
center, and the intention of this measure is for the County to take action to increase access to parks and open space, the project would partially fulfill this measure because it would include a public plaza and play area.

CE-4: Ensure residents have equitable,
year-round access to affordable, local
fresh food.

Not applicable. The intention of this measure is for the County to take action to ensure residents have access to food, which is not within the scope of a County services center.

CE-5: Ensure that large industrial facilities
act as good neighbors.

Not applicable. The project is not a large industrial
facility.

L-1: Establish Contra Costa County as a
leader among local governments for
addressing climate issues.

Not applicable. The measure focuses on county-wide
leadership and policy initiatives, which is not within the scope of a County services center.

L-2: Continue to recognize the climate
crisis as an emergency for Contra Costa
County and make addressing climate
change a top County priority.

Not applicable. This measure pertains to county-level
policy and prioritization, which is not within the scope of a County services center.

IS-1: Monitor and report progress toward
achieving Climate Action and Adaptation
Plan goals on an annual basis.

Not applicable. This measure pertains to county-level
monitoring and reporting, which is not within the scope of a County services center.

IS-2: Continue collaborative partnerships
with public agencies, private partners, and
community groups that support Climate
Action and Adaptation Plan
implementation, with an emphasis on
residents and community-based
organizations from affected communities.

Not applicable. The project does not involve formal
partnerships for climate action plan implementation
because that is not within the scope of a County services center.

IS-3: Secure necessary funding to
implement the Climate Action and
Adaptation Plan.

Not applicable. This measure involves securing funding
for climate action plan implementation, which is not
within the scope of a County services center.

IS-4: Continue to update the baseline
emissions inventory and Climate Action
and Adaptation Plan every 5 years.

Not applicable. This measure involves updating the
emissions inventory in the CAAP, which is not within the scope of a County services center.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-47 February 2026 Climate Action Strategy Project Consistency
IS-5: Maintain and update the Climate
Action and Adaptation Plan to allow for
greater resilience.

Not applicable. This measure involves maintaining and
updating the climate action plan, which is not within the scope of a County services center.

As demonstrated in Table 2-9, the project would be consistent with all applicable County 2024 CAAP climate action strategies. The project would not generate GHG emissions, either directly or indirectly, that may have a significant impact on the environment. Therefore, the project would have a less-than-significant impact.
b) Would the project conflict with an applicable plan, policy, or regulation adopted for the purpose of reducing emissions of greenhouse gases?
California Senate Bill 375/Plan Bay Area 2050
Plan Bay Area 2050, the RTP/SCS for the San Francisco Bay Area, was prepared by MTC pursuant to the requirements of SB 375, as discussed in the Regulatory Setting section. Plan Bay Area 2050 is a state-mandated, integrated long-range transportation and land use plan that demonstrates reductions in GHG emissions from passenger cars and light-duty trucks (CARB 2025b).

The project would be consistent with the type and level of development in the City General Plan, which underpins the growth and development assumptions for Plan Bay Area 2050. The project would also be less than 0.25 mile from the Brentwood Boulevard and Sand Creek Road bus stop, with service from Tri Delta Transit's 300X Brentwood Park & Ride/Antioch BART line (Tri Delta Transit 2025). Thus, the project would be consistent with Plan Bay Area 2050 goals that encourage the use of transit as an alternate method of transportation. By redeveloping vacant parcels within existing urban growth boundaries, the project would also support Plan Bay Area 2050 Strategy EN 4 (maintain urban growth boundaries). Moreover, approximately half of the project site is within the MTC-/ABAG-designated Brentwood Boulevard Priority Development Area. The project would therefore result in new jobs in an area near existing job centers and frequent transit that has been identified for its contribution to growth (MTC/ABAG 2021b). Finally, as described in Section 2.17, Transportation, the project would have a less-than-significant impact with respect to VMT. Because the project would support Plan Bay Area 2050 goals to reduce VMT and GHG emissions from passenger cars and light-duty trucks, and because its proposed land use types and sizes would fit within the envelope of the uses assumed in Plan Bay Area 2050, the project would not conflict with implementation of Plan Bay Area 2050. Therefore, the project would have a less-than-significant impact.

CARB 2022 Scoping Plan
As explained in the Regulatory Setting section, CARB’s 2022 scoping plan outlines the main strategies the state will use to keep California on track with respect to meeting its SB 32 GHG reduction target (i.e., at least 40 percent below 1990 emissions by 2030, with carbon neutrality by 2045 and a reduction in anthropogenic emissions of 85 percent relative to 1990 levels) (CARB 2022a). Appendix D to CARB’s 2022 scoping plan identifies key project attributes that, according to empirical evidence, reduce operational GHG emissions while simultaneously advancing fair housing.

In the 2022 scoping plan, CARB concludes that:
[r]esidential and mixed-use projects that have all of the key project attributes in Table 3 [Key Residential and Mixed-Use Project Attributes that Reduce GHGs] should accommodate growth in a manner consistent with state GHG reduction and equity prioritization goals (CARB 2022b).

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-48 February 2026 In accordance with CARB’s guidance, this analysis evaluates the project’s consistency with the scoping plan–identified key project attributes to determine whether the project would conflict with the state’s plan for meeting its GHG reduction targets. The project’s consistency with the attributes is discussed in Table 2-10.

Table 2-10. Project Consistency with CARB 2022 Scoping Plan Key Project Attributes Project Attribute Project Consistency
Transportation Electrification
Provides EV charging infrastructure that, at a
minimum, meets the most ambitious voluntary
standard in the California Green Building
Standards Code at the time of project approval
Inconsistent. The project would include 108 EV-capable
spaces, with 82 Type 2 EV chargers and four directcurrent fast charging stations. This amount of EV parking would not meet the voluntary Tier 2 standards for EV
charging infrastructure outlined in CALGreen. As such,
the project would be inconsistent with this attribute.

VMT Reduction
Is located on infill sites that are surrounded by
existing urban uses and reuses or redevelops
previously undeveloped or underutilized land
that is presently served by existing utilities
and essential public services (e.g., transit,
streets, water, sewer)
Consistent. The project site is a flat, grassy undeveloped lot. The lot is within a suburban community that is
presently served by existing utilities and essential public services, like streets and transit. As such, the project would be consistent with this attribute.

Does not result in the loss or conversion of
natural and working lands
Consistent. The project site is a flat, grassy undeveloped lot with no trees. The lot is within the existing growth boundary of a suburban community. The site lacks land
use features identified by CARB as indicative of natural and working lands, including forestland, rangeland,
urban green space, wetlands, or farmland (CARB 2025a).

The project would not result in the loss or conversion of natural and working lands. As such, the project would be consistent with this attribute.

Consists of transit-supportive densities
(minimum of 20 residential dwelling units per
acre), or
Is in proximity to existing transit stops (within
a half mile), or
Satisfies more detailed and stringent criteria
specified in the region’s SCS.

Consistent. As previously noted, the project would be
less than 0.25 mile from the Brentwood Boulevard and
Sand Creek Road bus stop, with service from Tri Delta
Transit’s 300X Brentwood Park & Ride/Antioch BART
line (Tri Delta Transit 2025). As such, the project would be consistent with this attribute.

Reduces parking requirements by:

Eliminating parking requirements or including
maximum allowable parking ratios (i.e., the
ratio of parking spaces to residential units or
square footage); or
Providing residential parking supply at a ratio
of less than one parking space per dwelling
unit; or
For multi-family residential development,
Consistent. As discussed above, there is no County
zoning designation for the project site. However, in both Section 84-46 of the County Municipal Code
(Administrative Office District) and Section 17.620 of the City Municipal Code, office uses are required to provide one off-street parking space per 200 square feet of gross floor area. Given the proposed 120,000 square feet of
office space, the project would require 600 parking
spaces. With 424 spaces proposed, the project would
provide fewer spaces than required. As such, the project would provide less parking than the standard ratio

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-49 February 2026 Project Attribute Project Consistency
requiring parking costs to be unbundled from
costs to rent or own a residential unit.
specified in the municipal code. The project would be
consistent with this attribute.

At least 20 percent of units included are
affordable to lower-income residents
Inapplicable. The project does not propose the
development of any residential units. As such, this
attribute does not apply to the project.

Results in no net loss of existing affordable
units
Consistent. There are currently no affordable housing
units on the project site. As such, development of the
project would not result in a net loss of existing
affordable units, consistent with this attribute.

Uses all-electric appliances without any
natural gas connections and does not use
propane or other fossil fuels for space heating,
water heating, or indoor cooking
Consistent. As discussed under Impact a, the project
would not include natural gas appliances or natural gas plumbing. As such, the project would be consistent with this attribute.

Source: CARB 2022a.

As discussed in Table 2-10, the project would not meet the voluntary CALGreen Tier 2 EV parking standard identified in Appendix D. However, Appendix D notes that “lead agencies may determine, with adequate additional supporting evidence, that projects that incorporate some, but not all, of the key project attributes are consistent with the state’s climate goals” (CARB 2022). Although the project would not meet the voluntary CALGreen Tier 2 EV parking standard, the project would be consistent with all applicable County 2024 CAAP climate action strategies because it would include a relatively large amount of EV parking, as well as 58 bicycle parking spaces, and be in proximity to an existing transit station. Moreover, as discussed in Table 2-10, the project would incorporate all other scoping plan–identified key project attributes. As a LEED Silver all-electric facility with an on-site solar photovoltaic and geothermal HVAC system, the project would be consistent with CARB’s 2022 scoping plan and align with the state’s climate goals.

Because the project would contribute its fair share to what will be required to achieve the state’s most recent long-term climate goals, per Air District guidance, and align with the state’s climate strategies, as defined in Appendix D, the project would not conflict with implementation of CARB’s 2022 scoping plan or attainment of the statewide GHG targets for 2030 and 2045 mandated by SB 32 and AB 1279, respectively. Therefore, the project would have a less-than-significant impact.

2.8.2 Sources of Information
Bay Area Air District. 2023. California Environmental Quality Act Air Quality Guidelines. April.

Available: https://www.baaqmd.gov/plans-and-climate/california-environmental-quality-actceqa/updated-ceqa-guidelines. Accessed: June 2025.

California Air Pollution Control Officers Association. 2022. California Emissions Estimator Model User Guide. April. Available: https://caleemod.com/documents/user-guide/CalEEMod_User_Guide_ v2022.1.pdf. Accessed: June 2025.

California Air Resources Board. 2017. California’s 2017 Climate Change Scoping Plan: The Strategy for Achieving California’s 2030 Greenhouse Gas Target. November. Available:
https://www.arb.ca.gov/cc/scopingplan/scoping_plan_2017.pdf. Accessed: June 2025. ———. 2022a. 2022 Scoping Plan for Achieving Carbon Neutrality. November. Available:
https://ww2.arb.ca.gov/sites/default/files/2022-12/2022-sp_1.pdf. Accessed: June 2025.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-50 February 2026 ———. 2022b. 2022 Scoping Plan: Appendix D, Local Actions. November. Available:
https://ww2.arb.ca.gov/sites/default/files/2022-11/2022-sp-appendix-d-local-actions.pdf.

Accessed: June 2025.
———. 2025a. Natural and Working Lands: About. Available: https://ww2.arb.ca.gov/ourwork/programs/natural-and-working-lands/about. Accessed: June 2025. ———. 2025b. SB 375 Regional Greenhouse Gas Emissions Reduction Targets. Available:
https://ww2.arb.ca.gov/our-work/programs/sustainable-communities-program/regionalplan-targets. Accessed: June 2025.

City of Brentwood. 2014. City of Brentwood General Plan. Adopted July 22, 2014. Available:
https://www.brentwoodca.gov/home/showpublisheddocument/2900/638700285520700000.

Accessed: June 2025.

Contra Costa County. 2024a. Envision 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. Accessed: July 2025. ———. 2024b. Contra Costa County 2024 Climate Action and Adaptation Plan. Adopted November 5, 2024. Available: https://www.contracosta.ca.gov/DocumentCenter/View/84967/Contra-CostaCounty-2024-Climate-Action-and-Adaptation-Plan-PDF?bidId=. Accessed: July 2025.

Intergovernmental Panel on Climate Change. 2007. Climate Change 2007: The Physical Science Basis.

Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Available: https://www.ipcc.ch/site/assets/uploads/2018/05/ ar4_wg1_full_report-1.pdf. Accessed: June 2025.
———. 2018. Global Warming of 1.5°C. Contribution of Working Group I, II, and III (Summary for Policy Makers). Available: https://www.ipcc.ch/site/assets/uploads/sites/2/2022/06/ SPM_version_report_LR.pdf. Accessed: June 2025.

Metropolitan Transportation Commission/Association of Bay Area Governments. 2021a. Plan Bay Area 2050. Adopted: October 21. Available: https://www.planbayarea.org/sites/default/files/ documents/Plan_Bay_Area_2050_October_2021.pdf. Accessed: June 2025. ———. 2021b. Plan Bay Area 2050 Growth Geographies. Available: https://opendata.mtc.ca.gov/ datasets/MTC::plan-bay-area-2050-growth-geographies/explore?location=37.946660%2C121.698464%2C16.50. Accessed: June 2025.

Tri Delta Transit. 2025. 300X Brentwood Park & Ride/Antioch BART Schedule. Effective: January 12, 2025. Available: https://trideltatransit.com/wp-content/uploads/2024/05/300X-Weekdaysonly.pdf. Accessed: June 2025.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-51 February 2026

2.9 Hazards and Hazardous Materials
Potentially
Significant
Impact
Less than
Significant with
Mitigation
Incorporated
Less-thanSignificant
Impact No Impact
Would the project:
a) Create a significant hazard to the public or the environment through the routine transport, use, or disposal of hazardous materials?
b) Create a significant hazard to the public or the environment through reasonably foreseeable upset and accident conditions involving the release of hazardous materials into the
environment?
c) Emit hazardous emissions or involve handling hazardous or acutely hazardous materials, substances, or waste within 0.25 mile of an existing or proposed school?
d) 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?
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, result in a safety hazard or excessive noise for people residing or working in the project area?
f) Impair implementation of or physically interfere with an adopted emergency response plan or emergency evacuation plan?
g) Expose people or structures, either directly or indirectly, to a significant risk of loss, injury or death involving wildland fires?

2.9.1 Discussion
A Soil Investigation Report, a Phase I Environmental Site Assessment (ESA), and Phase II ESA were prepared for the project by Baseline Environmental Consulting (refer to Attachment C) (Baseline Environmental Consulting 2024, 2025a, and 2025b). In addition, Baseline Environmental Consulting performed a peer review for a letter prepared by ACC Environmental Consultants regarding management of pesticide-containing soils (refer to Attachment C) (Baseline Environmental Consulting 2025c). The Soil Investigation Report, Phase I ESA, Phase II ESA, and peer review are summarized as part of Impact b, below.
a) Would the project create a significant hazard to the public or the environment through the routine transport, use, or disposal of hazardous materials?
Project construction would involve the routine transport, use, and disposal of hazardous materials such as solvents, paints, oils, grease, and caulking. Such transport, use, and disposal must comply with applicable regulations. Although solvents, paints, oils, grease, and caulking would be transported, used, and disposed of during the construction phase, these materials are commonly handled on a temporary basis during construction projects; however, their use would not represent the routine transport, use, and disposal of acutely hazardous materials. Any spills or releases involving these materials are expected to be small, localized, and cleaned up as they occur. In

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-52 February 2026 addition, a SWPPP would be prepared and implemented during project construction for coverage under the required Construction General Permit,7 in accordance with the requirements of the State Water Resources Control Board (SWRCB) (2025). The SWPPP would require implementation of BMPs regarding hazardous materials storage, soil stockpiles, inspections, maintenance, employee training, and containment to prevent runoff from entering stormwater collection systems or waterways.

Long-term maintenance activities would involve the use of hazardous chemicals that are typical in an office building environment. Maintenance within the service center would require the use of a wide variety of commercial products that are formulated with hazardous materials (e.g., fuels, cleaners and degreasers, solvents, paints, lubricants, adhesives, sealers, pesticides/herbicides). Such materials are considered common. They are unlikely to be stored or used in large quantities. Any spills involving these materials would be small and localized and cleaned up as they occur.

Therefore, the project would have a less-than-significant impact. b) Would the project create a significant hazard to the public or the environment through reasonably foreseeable upset and accident conditions involving the release of hazardous materials into the environment?
Due to its historical agricultural use and potential for agriculturally-related chemical8 contamination on-site (the project site and adjacent properties were used for agriculture as early as 1939), multiple environmental site investigations have been conducted on-site. The following is a summary of the reports reviewed during preparation of this analysis:
• Soil Investigation Report, Proposed East County Service Center, Contra Costa County Project #WH429A, Brentwood, California,
9 dated October 3, 2024 (refer to Attachment C), which
identified the following:
o Eight borings were advanced to maximum depths of 2 to 2.5 feet below ground surface (bgs). Locations are denoted in Figure 1 of the soil investigation report. Samples were analyzed for organochlorine pesticides (OCPs), arsenic, metals, total petroleum hydrocarbons, and volatile organic compounds.
o Concentrations of arsenic exceeded commercial environmental screening levels (ESLs) and construction worker ESLs; however, the arsenic concentrations were considered to be within naturally occurring background levels. Thus, no specific handling or 7 Construction activity subject to this permit includes clearing, grading, and disturbances to the ground such as stockpiling or excavation. Dischargers whose projects disturb 1 acre or more of soil or whose projects disturb less than 1 acre but are part of a larger common plan of development that in total disturbs 1 acre or more are required to obtain coverage under the National Pollutant Discharge Elimination System (NPDES) General Permit for Stormwater Discharges Associated with Construction and Land Disturbance Activities. Construction grading as part of the project is anticipated to cover approximately 7.86 acres. 8 Prior to 1950, inorganic pesticides that contained elevated concentrations of metals, such as arsenic, were commonly used in California agriculture. After 1950, OCPs were commonly used in California agriculture until about the mid-1970s. Arsenic from inorganic pesticides and residue from OCPs used in the past have the potential to persist for many decades in shallow soils (where they were applied and generally remain). This can affect human health and the environment. Groundwater in the project site’s near vicinity has been recorded at 11 feet bgs; thus, on-site groundwater was not considered at risk of being affected by OCP contamination in shallow soil. 9 The Soil Investigation Report covers the northern portion of the project site, including the following Assessor’s Parcel Numbers: 016‐410‐008, 016‐410‐009, 016‐410‐010, 016‐410‐011, 016‐410‐012, and 016‐410‐013.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-53 February 2026 disposal requirements were recommended, other than a notification to the contractor redeveloping the site to ensure proper precautions are taken. o Soils sampled from portions of the site (western, north‐central, and northeastern) were considered non-hazardous, while others (south‐central and southeastern) were considered California hazardous (or non-Resource Conservation and Recovery Act [RCRA] hazardous) waste for off-site disposal purposes; this based on the analytical results for OCPs exceeding California hazardous waste criteria. o No other results exceeded hazardous waste criteria.
o The soil investigation report recommended that a soil management plan (SMP) be prepared and implemented during construction activities (Baseline 2024). The SMP would outline how soil would be segregated, managed, tested, reused, and disposed of during excavation and grading.
• Phase I Environmental Site Assessment, Proposed East County Service Center (Southern Site), Contra Costa County Project #WH429A, Brentwood, California,10 (Phase I ESA) dated January 15, 2025 (refer to Attachment C), which identified the following conclusions and recommendations:
o No recognized environmental conditions (RECs) were identified associated with the site. o One item of environmental concern was identified. It was noted as potential pesticide contamination (arsenic and organochlorine pesticides) from historical agricultural use. o The Phase I ESA recommended that a Phase II ESA be prepared to collect and evaluate shallow soil samples for potential pesticide contamination within the southern site. Results should be provided to applicable contractors to incorporate into their health and safety and hazard communication programs.
• Phase II Environmental Site Assessment, Proposed East County Service Center Southern Propoerty, Assessor’s Parcel Number 016‐120‐024, Contra Costa County Project #WH429A, Brentwood, California,
11 (Phase II ESA) dated February 10, 2025 (refer to Attachment C), which identified the following:
o Ten borings were advanced to a maximum depth of 2 feet bgs. Locations are denoted in Figure 1 of the Phase II ESA. Samples were analyzed for OCPs, arsenic, metals, total petroleum hydrocarbons, and volatile organic compounds. o Concentrations of arsenic exceeded commercial environmental screening levels (ESLs) and construction worker ESLs; however, the arsenic concentrations were considered to be within naturally occurring background levels. Thus, no specific handling or disposal requirements were recommended, other than a notification to the contractor redeveloping the site to ensure proper precautions are taken. o Surface soils (to a depth of 1.5 feet bgs) should be classified as California hazardous (or non‐ RCRA hazardous) waste for off-site disposal; this based on the analytical results for OCPs exceeding California hazardous waste criteria.
10 The Phase I ESA covers the southern portion of the project site, including the following Assessor’s Parcel Number: 016-120-024.
11 The Phase II ESA covers the southern portion of the project site, including the following Assessor’s Parcel Number: 016-120-024.

Contra Costa County Public Works Department Environmental Checklist East County Service Center (County Project No. WH429A)
Initial Study/Mitigated Negative Declaration 2-54 February 2026 o No other results exceeded hazardous waste criteria.
o The Phase II ESA recommended a SMP be prepared and implemented during construction activities.
• Peer Review of ACC Letter Regarding Management of Pesticide-Containing Soils, Planned East County Service Center, Brentwood, California (Peer Review Memorandum), dated November 14, 2025 (refer to Attachment C), which identified the following:
o Baseline Environmental Consulting performed a peer review on behalf of the County of an October 2025 letter prepared by ACC Environmental Consultants regarding on-site management of pesticide-containing soils. The letter provided the professional opinion of ACC Environmental Consultants, following review of the soil investigation report and Phase II ESA summarized above.
o According to the peer review memorandum, the County approves of on-site reuse of soil that would be classified as California hazardous (or non RCRA-hazardous) waste for off-site disposal if it would not cause an unacceptable risk to human health. The County and Baseline Environmental Consulting, based on analytical results of the prior investigations summarized above (refer to Attachment C), determined the only potential unacceptable risk to human health would be potential exposure to Toxaphene concentrations above the residential ESLs in the planned planter/bioswale and playground areas within the northern portion of the project site.
o Baseline Environmental Consulting recommended the excavation of existing soil within the planter/bioswale and playground areas to a depth of approximately 1.5 feet bgs (locations noted in Figure 1 of the peer review memorandum). The affected material should be replaced with imported clean fill or on-site soil acceptable for reuse. The affected material can be reused on-site as fill material beneath hardscape.

As described above, the project site has undergone multiple site investigations. These investigations concluded that no RECs are associated with the project site. Soil sampling resulted in the classification of on-site soils as California hazardous (or non‐RCRA hazardous) waste for off-site disposal. In addition, the 2025 peer review memorandum (summarized above) identified the potential exposure to Toxaphene-affected soils in the planned planter/bioswale and playground areas as an unacceptable risk to human health. Therefore, exposure impacts to construction workers would be potentially significant. Implementation of Mitigation Measure HAZ-1, below, would require preparation and implementation of a SMP during all ground disturbance (as recommended in the 2024 Soil Investigation Report and the 2025 Phase II ESA). Therefore, the project would have a less-than-significant impact with mitigation incorporated.

Mitigation Measure HAZ-1: Soil Management Plan
The County or its contractor(s) shall prepare and implement, during site preparation and grading activities, an SMP consistent with the recommendations in the Phase II ESA and peer review memorandum prepared for the proposed project. The SMP shall be designed to protect human health and the environment. It shall include protocols (including additional sampling, as necessary), measures, and techniques for the proper handling, management, and disposal of affected materials found on the site during site preparation, grading, excavating, and other earth-disturbing activities. The SMP shall also be designed to protect workers and off-site receptors during site activities and ensure the proper characterization, management, and/or