Agenda packet — Lake Forest City Council, March 17, 2026 (part 2 of 9)

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RESOLUTION NO. 2026-07

A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF LAKE

FOREST, CALIFORNIA, APPROVING SITE DEVELOPMENT
PERMIT 05-25-5800 TO DEMOLISH THE EXISTING MOVIE
THEATER BUILDING AND SITE IMPROVEMENTS AT 26602
TOWNE CENTRE DR AND CONSTRUCT A NEW 34-FT TALL,
165,068 GROSS SQ. FT. COSTCO WHOLESALE RETAIL

BUILDING TO INCLUDE SURFACE-LEVEL PARKING,

LANDSCAPING, SEASONAL OUTDOOR SALES AND DISPLAY

AREAS, AND OTHER ASSOCIATED IMPROVEMENTS AND USE
PERMIT 05-25-5803 FOR EXCEPTIONS TO THE MIXED USE

DEVELOPMENT STANDARDS AND DETERMINING THE

PROJECT TO BE EXEMPT FROM CEQA
WHEREAS, on May 27, 2025, Costco Wholesale ("Applicant") filed a Site Development Permit application to develop a 16.3-acre parcel at 26602 Towne Centre Dr, with a retail building for Costco Wholesale including the demolition of the existing movie theater building and accompanying site improvements and constructing a new 34 ft tall, 165,068 gross sq. ft. building with associated parking, landscaping, seasonal outdoor sale and display areas, and other associated improvements (the proposed "Project”); and
WHEREAS, the Project site is located within Phase 4 of the Foothill Ranch Towne Centre (“FRTC”), which was initially approved by the County of Orange under Planning Application (PA) 1998-69; and
WHEREAS, the project site is zoned Mixed Use 43 (“MU 43”) within the Foothill Ranch Planned Community (“FRPC”) and is designated Mixed Use 43 on the General Plan Land Use Map; and
WHEREAS, pursuant to the FRPC, the project is subject to the land use regulations and site development standards contained therein, and in the Lake Forest Municipal Code (“LFMC”), including Chapter 9.168 (Off-street Parking). In accordance with the FRPC, site improvements are permitted subject to approval of a Site Development Permit application; and
WHEREAS, Section 9.73.064 of the LFMC outlines that exceptions to the mixed-use development regulations may be requested using a Use Permit, of which the applicant has requested exceptions to the open space, massing beaks, and vertical articulation provisions; and
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WHEREAS, on February 5, 2026, the Planning Commission conducted a duly-noticed public hearing to consider Site Development Permit 05-25-5800 and Use Permit 05-25-5803, and approved the Project; and
WHEREAS, an appeal was subsequently filed by Lozeau Drury LLP on behalf of the Supporters Alliance for Environmental Responsibility (“SAFER”); and
WHEREAS, the City gave notice of the public hearing at which the project would be considered by the City Council by publishing a notice in a newspaper of general circulation and by posting a notice at City Hall on March 5, 2026; and WHEREAS, on March 17, 2026, the City Council conducted a duly-noticed public hearing to consider Site Development Permit 05-25-5800 and Use Permit 05-25-5803, at which interested persons had an opportunity to testify in support of, or opposition to the Project, and at which the City Council considered the application; and
WHEREAS, all other legal prerequisites to the adoption of this Resolution have occurred.

NOW THEREFORE, THE CITY COUNCIL OF THE CITY OF LAKE
FOREST DOES RESOLVE, DETERMINE, FIND AND ORDER AS FOLLOWS:

SECTION 1. Incorporation of Recitals. The City Council hereby finds and determines that the Recitals above are true and correct and incorporated herein.

SECTION 2. California Environmental Quality Act. The City Council finds that the proposed project is exempt from the provisions of the California Environmental Quality Act (CEQA) pursuant to Article 12 – Special Situations, Sec. 15183, Projects Consistent with a Community Plan, General Plan, or Zoning, of the CEQA Guidelines. This exemption applies to projects which are consistent with the development density established by existing zoning, community plan, or general plan policies for which an EIR was certified shall not require additional environmental review, except as might be necessary to examine whether there are project-specific significant effects which are peculiar to the project or its site. A technical memorandum prepared by the City’s consultant and further describing this exemption and its applicability to the project has been prepared in compliance with the provisions of CEQA, and is also incorporated by reference.

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SECTION 3. FINDINGS. With regard to Site Development Permit 05- 25-5800 and Use Permit 05-25-5803, the Lake Forest City Council hereby finds, based on consideration of the whole record before it, as follows:
1) General Plan Consistency: The use or project proposed is consistent with the General Plan.

The project site is designated Mixed Use 43 (“MU 43”) on the General Plan Land Use Element Map. The MU 43 designation “provides opportunities for mixtures of commercial, office, and residential uses in the same building, on the same parcel of land, or within the same area.” While the designation allows for both vertical and horizontal integration of compatible uses, single-use projects are allowed. The proposed retail use is consistent with the purpose and intent of the MU 43 designation and is proposed to be located in an area already developed with commercial and office uses.

Parcels with an MU 43 designation are subject to a maximum floor area ratio (“FAR”) of 1.2:1. FAR is a ratio of total building floor area to total land area. The project FAR is 0.23:1, which is well below the General Plan’s maximum development intensity. The project is also consistent with the following General Plan Land Use Element goals and policies:

Goal LU-2: A community where new development blends harmoniously into the existing neighborhood fabric.

Policy LU-2.1: Ensure that new development fits within the existing community setting and is compatible with surrounding land uses and public infrastructure availability.

Goal LU-3: A distinct community image and identity that promotes Lake Forest as a desirable place to live and do business.

Policy LU-3.4: Promote high-quality design for all public and private development projects, including building form, site design, landscaping, lighting, signage, and other components which impact the visual quality of a project.

Goal LU-4: A community with streetscapes that enhance the economic vitality and overall visual quality of the City, support the circulation network, and encourage pedestrian-scale streets and patterns of activity.

Policy LU-4.3: Reduce the bulk and perceived size of large buildings by dividing their mass into smaller parts, stepping down to adjacent structures, recessing openings for doors/windows, and using pedestrianscale features; single-plane massing is discouraged.

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Policy LU-4: Require and enforce appropriate residential and nonresidential development standards, including adequate building setbacks, to ensure that a building’s footprint does not negatively affect adjacent uses or the visual quality of the area.

Goal LU-5: Focus areas for economic stability and growth. A community featuring mixed-use activity centers located along the City’s major roadways and transportation facilities which allow for the co-location and harmonious development of housing, shopping, jobs, and public uses. 2) Zoning Code: The use, activity, or improvement(s) proposed by the application is consistent with the provisions of the Zoning Code.

The Foothill Ranch Planned Community Development Plan (“FRPC”) and Supplemental Text establishes land use and development regulations for all property within the FRPC boundaries. Properties falling within the Mixed-Use zoning designation are subject to Section 9.73 of the Lake Forest Municipal Code (“LFMC”). Retail uses are permitted by right, with projects involving new building construction subject to a Site Development Permit review and approval process.

Applicable development standards include a 65-ft. height limit, a 10-ft. minimum setback (15-ft when abutting an arterial street), and screening of loading areas, outdoor storage and mechanical equipment from public view. The proposed project is consistent with the applicable development standards of the LFMC, unless otherwise excepted per Use Permit 05-25- 5803.

The spirit and intent of the mixed-use building design and articulation regulations is to ensure development in the mixed-use zoning districts includes high quality, architecturally interesting buildings The applicant’s requested exceptions to the mixed-use development standards pertain to the provisions of open space, building massing breaks, and building vertical articulation. The applicant has incorporated design elements which break up the appearance of the building without creating a repetitive appearance of massing breaks, should the code be strictly followed. In addition, the applicant has maximized the open space on the site through landscape elements. The proposed landscaping continues the existing landscape design elements present in the Foothill Ranch Towne Centre, such as palm tree lines driveways, landscaped planters, and site boundary landscaping. The applicant’s proposed 8.8% open space marks a 0.7% increase from the existing open space that is on site as presently developed and further allows the applicant to maintain shared driveways and drive aisles and meet minimum parking requirements.

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The project requires on-site parking based on the parking to building floor area ratios specified in LFMC Chapter 9.168. The project location within Phase 4 of the FRTC, which meets the criteria to be parked at the shopping center ratio of 1 space for every 200 sq. ft., with the exception of the three Towne Centre Office Buildings (26632, 26642, & 26672 Towne Centre Dr), which are parked at the standard office ratio of 1 space for every 250 sq. ft. of gross floor area. All users within Phase 4 share parking facilities.

The project provides 2,068 parking spaces, which is a surplus of 74 spaces over the number required by the LFMC, including all required disabled accessible and electric vehicle charging stalls per the California Building Standards Code (CBSC). In addition, the project will provide 28 carpool spaces, 14 vanpool spaces, 46 short term bicycle racks, and 20 long-term bicycle lockers/racks in accordance with the CBSC and Chapter

9.160 of the LFMC.
3) CEQA: The approval of the permit application is in compliance with the requirements of the California Environmental Quality Act The proposed project is exempt from the provisions of the California Environmental Quality Act (CEQA) pursuant to Article 12 – Special Situations, Sec. 15183, Projects Consistent with a Community Plan, General Plan, or Zoning, of the CEQA Guidelines. This exemption applies to projects which are consistent with the development density established by existing zoning, community plan, or general plan policies for which an EIR was certified shall not require additional environmental review, except as might be necessary to examine whether there are project-specific significant effects which are peculiar to the project or its site. A technical memorandum prepared by the City’s consultant and further describing this exemption and its applicability to the project has been prepared in compliance with the provisions of CEQA, and is also incorporated by reference.
4) Compatibility: The location, size, design and operating characteristics of the proposed use will not create significant noise, traffic or other conditions or situations that may be objectionable, detrimental or incompatible with other permitted uses in the vicinity.

The proposed project is located in an already developed regional shopping center containing various commercial and office uses. The proposed building would be of a similar size to other anchor uses elsewhere within the Foothill Ranch Towne Centre and would be a retail use on a property Item: 11
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that is presently developed with and historically utilized as a retail use. The building design has incorporated elements of the Design Guidelines to ensure a compatible design with the surrounding uses
Furthermore, the project’s technical studies, which includes a noise impact analysis, concluded that the use will not have adverse impacts on surrounding properties with incorporation of standard conditions of approval. Additionally, a traffic study prepared for the project and reviewed by the City’s Traffic Engineering Manager concluded that the project will not result in traffic levels on adjacent roads that exceed the City’s standards. Site access with be provided via existing driveways along Towne Centre Drive and the project will utilize the existing circulation patterns connecting with the rest of the Foothill Ranch Towne Centre.

Trucks deliveries will occur at the rear of the building away from significant customer traffic, similar to the surrounding retail users before exiting the site along a defined path, minimizing conflicts with the surrounding users.

Ample open parking will be maintained with an excess of parking stalls available for all users within Phase 4 of the Foothill Ranch Towne Centre.

Should future projects within the Foothill Ranch Towne Centre propose residential development, additional planning studies would be required as part of those projects to ensure compatibility with the existing and future uses.
5) General Welfare: The application will not result in conditions or circumstances contrary to the public health and safety and the general welfare.

The Project's CEQA Environmental Compliance Checklist and technical studies determined that the proposed project will not result in adverse impacts to surrounding properties or the environment with implementation of standard conditions of approval. Therefore, the application will not result in conditions or circumstances contrary to the public health and safety and the general welfare.
6) Development Fees for Provision of Public Facilities:

Pursuant to the LFMC, the development will be subject to payment of all applicable development fees at the time of building permit issuance. 7) City Design Guidelines: The project has been reviewed in accordance with Citywide Design Guidelines and is consistent with the purpose and intent of the guidelines.

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The following guidelines, along with additional guidelines listed in an attachment to the staff report, are deemed applicable to the project:
• Buildings should contain low, medium and high elevation massing elements. Vertical and horizontal offsets should be provided to minimize building bulk.
• Building color and materials may also be used to emphasize elevation massing elements.
• Vehicular entries to commercial development should be enhanced with ornamental landscaping, decorative paving, raised medians, gateway structures and/or monument signage.
• Ensure that efforts to accommodate freeway-oriented signage and elevations do not detract from the overall building appearance. • Use consistent architecture on all sides, given high visibility of the corridor
• Incorporate landscaping that softens the appearance of buildings along the freeway.
• In designing fencing along the freeway, incorporate colors and materials compatible with the building architecture, to the fullest extent possible.

The proposed project complies with the purpose and intent of the guidelines, as follows:

The project design features elements, such as variation in materials, elevation, and massing, to provide visual interest. All rooftop equipment will be screened in a manner that is architecturally consistent with the rest of the building. Landscaping is proposed to buffer the property from SR241, in addition to soften the appearance along the sides of the building that are visually prominent to the public. Common landscape theming is continued that is typical for the Foothill Ranch Towne Centre, including palm tree lines driveways and landscaped pedestrian pathways.

SECTION 4. CITY COUNCIL ACTIONS. The City Council hereby takes the following actions:

1. Approves a CEQA exemption for the project pursuant to Article 12 – Special Situations, Sec. 15183, Projects Consistent with a Community Plan, General Plan, or Zoning, and directs the Director of Community Development to prepare and file with the Clerk for the County of Orange a Notice of Exemption pursuant to the provisions of Public Resources Code Section 21152(b) and CEQA Guidelines Section 15062.

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A copy of the exemption notice shall be kept on file and available for public review at the City of Lake Forest City Hall, 100 Civic Center Drive, Lake Forest CA 92630.

2. Approves Site Development Permit 05-25-5800 to develop a 16.3-acre parcel at 26602 Towne Centre Dr, with a retail building for Costco Wholesale, including the demolition of the existing movie theater building and accompanying site improvements and constructing a new 34 ft tall, 165,068 gross sq. ft. building with associated parking, landscaping, seasonal outdoor sale and display areas, and other associated improvements.

3. Approves Use Permit 05-25-5803 for exceptions to the mixed-use development standards as it relates to open space, massing breaks, and vertical articulation.

CONDITIONS OF APPROVAL
SDP 05-25-5800 and UP 05-25-5803
The following conditions of approval shall apply to the Applicant, developer and/or property owner, whichever is appropriate for the condition.

1. Indemnification: The applicant shall indemnify, protect, defend, and hold the City, and/or any of its officials, officers, employees, agents, departments, agencies, and instrumentalities thereof, harmless from any and all claims, demands, lawsuits, writs of mandamus, and other actions and proceedings (whether legal, equitable, declaratory, administrative or adjudicatory in nature), and alternative dispute resolution procedures (including, but not limited to arbitrations, mediations, and other such procedures), judgments, orders, and decisions (collectively “Actions”), brought against the City, and/or any of its officials, officers, employees, agents, departments, agencies, and instrumentalities thereof, that challenge, attack, or seek to modify, set aside, void, or annul, any action of, or any permit or approval issued by the City and/or any of its officials, officers, employees, agents, departments, agencies, and instrumentalities thereof (including actions approved by the voters of the City) for or concerning the project, whether such Actions are brought under the Ralph M. Brown Act, California Environmental Quality Act, the Planning and Zoning Law, the Subdivision Map Act, Community Redevelopment Law, Code of Civil Procedure Sections 1085 or 1094.5, or any other federal, state, or local constitution, statute, law, ordinance, charter, rule, regulation, or any decision of a court of competent jurisdiction. It is expressly agreed that the City shall have the right to approve, which approval Item: 11
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will not be unreasonably withheld, the legal counsel providing the City’s defense, and that applicant shall reimburse City for any costs and expenses directly and necessarily incurred by the City in the course of the defense.

City shall promptly notify the applicant of any Action brought and City shall cooperate with applicant in the defense of the Action.

2. Expiration: Site Development Permit No. 05-25-5800 and Use Permit 05-25- 5803 shall expire 24 months from the date of approval if building permits for the project have not been issued and an extension of time has not been approved by the Director of Community Development.

3. The Planning Division processes discretionary applications on a deposit basis. Deposit funds are provided by applicants/developers to cover the actual costs associated with staff time and resources utilized in processing an application. If, at any time, the cost to process the application exceeds the deposit on file, additional funds shall be deposited by the Project Applicant/Developer. A final accounting for this project will be prepared following the City Council’s decision on the project and if needed, a request for additional funds will be provided to the Project Applicant/Developer.

Should additional funds be required, the Project Applicant/Developer shall submit a check or money order, payable to the City of Lake Forest, for the additional funds within 30 days, or prior to issuance of a grading permit for the project, whichever is earlier.

4. The conditions of approval listed herein shall be printed verbatim on each set of plans submitted to the City for building permits.

No More Than Three Days Prior To Grading or Construction Activities:

5. Migratory Bird Treaty Act Compliance. In the event that Project construction or grading activities occur during the bird nesting season (between January 15 and September 15), a qualified Avian Biologist shall conduct pre-construction Nesting Bird Surveys (NBS) prior to Project-related disturbance to nestable vegetation to identify any active nests. If no active nests are found, no further action will be required. If an active nest is found, the biologist shall set appropriate no-work buffers around the nest which shall be based upon the nesting species, its sensitivity to disturbance, nesting stage and expected types, intensity and duration of disturbance. The nests and buffer zones shall be field checked weekly by a qualified biological monitor. The approved no-work buffer zone shall be clearly marked in the field, within which no disturbance activity shall commence until the qualified biologist has determined the young birds have successfully fledged and the nest is inactive. Prior to commencement of grading activities and issuance of Item: 11
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any building permits, the applicant shall submit a copy of the NBS to the City and demonstrate that any required no-work buffers zones have been established.

6. Archaeological awareness training for Project personnel conducting ground disturbing activities shall be conducted by the Project Applicant/Contractor prior to the start of work.

The applicant shall comply with the following Conditions of Approval released by the City of Lake Forest Public Works Department:

General Requirements:

7. All submittals to the Public Works Department shall be made electronically, unless otherwise specified.

8. All design, construction, and inspection shall comply with the City of Lake Forest Municipal Code, Public Works Standards and Specifications, and applicable State and Federal regulations.

9. The applicant shall obtain all required Public Works permits (grading, encroachment, improvement, storm drain) prior to commencing work.

10. Plans shall be prepared, signed, and stamped by a California licensed civil engineer.

11. The applicant shall schedule a pre-construction meeting with Public Works staff prior to issuance of any permit.

Improvement Plans:

12. Final grading, street, and drainage plans shall be submitted to and approved by the City Engineer prior to permit issuance.

13. All improvements shall be consistent with conditions of Planning approval.

14. As-built plans signed by the project engineer shall be submitted upon project completion. The applicant shall provide complete "as-built" plans on 24"x36" of the appropriate scale mylar and electronic format AutoCad, latest version, in accordance with City standards prior to Public Works approval to release utilities and certificate of occupancy.

15. The applicant shall submit to Public Works for review and approval a precise landscape and irrigation construction plan prepared by a licensed landscape Item: 11
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architect for the project consistent with the landscape plans approved by the City Council.

Fees and Bonds:

16. The applicant shall pay all applicable plan check, inspection, and impact fees as required by City fee schedule.

17. Performance, labor, and material bonds shall be posted for all public improvements prior to issuance of permits.

18. A one-year warranty bond shall be required for all public improvements, effective upon acceptance by the City.

Grading and Drainage:

19. The final grading and drainage plans shall be 24” x 36”, ink on mylar, with elevations to nearest 0.01 foot, scale 1” = 20’

20. The applicant shall submit to Public Works for review and approval a final grading plan showing building footprints, new and revised pads and elevations of finished grades, drainage routes, retaining walls, erosion control, slope easements, typical sections at adjoining properties showing all details of drainage, and other pertinent information.

21. A plan check deposit shall be posted prior to checking. The grading plan shall make provisions to ensure that the on-site drainage shall be in compliance with the NPDES guidelines.

22. A final grading plan shall be approved by the City Engineer and demonstrate compliance with site hydrology and slope stability requirements.

23. All stormwater runoff shall be conveyed to approved drainage facilities without causing nuisance or damage to adjacent properties.

24. Erosion and sediment control measures shall be installed and maintained throughout construction.

25. A final Geotechnical report shall be prepared and reviewed by Public Works prior to any grading activity.

Vector Control:

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26. All approved structural Best Management Practices (BMPs) and LID site design elements shall be designed so as to not allow the propagation and breeding of vectors such as mosquitos, flies, and other insects, or rodents and other non-domesticated animals.

27. All approved structural Best Management Practices (BMPs) and LID site design elements shall be serviced or maintained at a minimum once per year so as to not allow the propagation and breeding of vectors such as mosquitos, flies, and other insects, or rodents and other non- domesticated.

Traffic:

28. Public Works inspectors shall have access to the site at all times for inspection.

29. Work not conforming to approved plans or City standards shall be removed and replaced at the applicant’s expense.

Project Close-Out:

30. The applicant shall request a final inspection upon completion of improvements.

31. All punch list items identified by Public Works must be corrected before acceptance.

32. Upon acceptance of public improvements, warranty period shall commence, after which performance bond may be released.

33. Maintenance agreements for private stormwater or utility facilities shall be recorded prior to project close-out.

34. Prior to the issuance of the Certificate of Occupancy, applicant shall provide a certificate of substantial completion signed and sealed by the licensed landscape architect of record confirming the landscaping and irrigation system have been installed per approved plans.

35. The following must be signed off by Public Works prior to the Building Division issuing a certificate of occupancy:
a) Grading meets CDC Section 1804.4
b) Grading
c) Drainage
d) Camera inspection for drainage lines
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e) WQMP structural BMPs
f) Landscaping
g) Irrigation
h) ADA compliance
i) Public Streets
j) Private Streets
k) Signals
l) Roadway Signage
m) Outstanding and violations/fines cleared
The applicant shall comply with the following Conditions of Approval released by the Orange County Fire Authority:

36. The applicant or responsible party shall submit the plan(s) listed below to the Orange County Fire Authority (OCFA) for review and approval prior to the issuance of a precise grading permit.
a. Fire master plan (service code PR145)

37. The applicant or responsible party shall submit the plan(s) listed below to the OCFA for review and approval prior to the issuance of a precise grading permit, as applicable:
a. Tanks storing hazardous materials (service codes PR300-PR305) b. Hazardous materials compliance and chemical classification (service codes PR315-PR328)
c. Hazardous equipment, processes, or operations (service codes PR345- PR360)
d. High-piled storage (service code PR330)
e. Battery (service code PR375), for any system containing an aggregate quantity of electrolyte in excess of 50 gallons
f. Emergency responder ratio system design (service code PR 928). This submittal may be deferred when acceptable to the Building Division, but the required conduit must be installed prior to concealing interior construction.
g. Underground piping for private hydrants and fire sprinkler systems (service code PR 470-PR475).

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h. Alternate methods and materials (AM&M) request (PR910).

38. Prior to concealing interior construction, the applicant or responsible party shall have completed the following:
a. Sprinkler monitoring system (service code PR500)
b. Fire alarm system (service codes PR 500-PR520)
c. Fire sprinkler system (service codes PR430-PR455)
d. Hood and duct extinguishing system (service code PR335)

39. Prior to occupancy, the applicant or responsible party shall have completed the following:
a. Emergency responder radio system testing (service code PR928)

40. Pre-submittal Meeting: Prior to issuance of grading permit or submittal of any fire master plans or architectural plans to the OCFA, the applicant or responsible party shall attend a pre-submittal meeting with an OCFA plan reviewer. Call OCFA Planning & Development Services at 714-573-6108 at least two weeks in advance to arrange for scheduling and payment for the pre-submittal meeting.

41. Preconstruction Meeting: Before commencement of construction, the applicant or responsible party shall attend a pre-construction meeting with an OCFA inspector. Call OCFA Inspection Scheduling at 714-573-6150 at least five days in advance to schedule and pay for the pre-construction meeting.

42. Lumber-drop Inspection: After installation of required fire access roadways and hydrants, the applicant shall receive clearance from the OCFA prior to bringing combustible building materials on-site. Call OCFA Inspection Scheduling at 714-573-6150 with the Service Request number of the approved fire master plan at least five days in advance to schedule the lumber drop inspection.

43. Temporary/Final Occupancy Inspections: Prior to issuance of temporary or final certificate of occupancy, all OCFA inspections shall be completed to the satisfaction of the OCFA inspector and be in substantial compliance with codes and standards applicable to the project and commensurate with the type of occupancy (temporary or final) requested. Inspections shall be scheduled at least five days in advance by calling OCFA Inspection Scheduling at 714-573-6150.

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44. Phased Occupancy: Phased occupancy of this structure shall be permitted only with prior approval from OCFA and the Building Official. Requests for phased occupancy shall be submitted for evaluation by OCFA as an alternate materials and methods proposal (PR910) accompanying the architectural submittal. Such requests shall be made prior to start of construction only.

45. Emergency Access Easements: Irrevocable reciprocal access easements for emergency access purposes to the benefit of the city shall be recorded concurrently with the final map or, where no final map is required, prior to approval of the fire master plan.

46. Secured Fire Protection Agreement: Prior to clearance of a final map for recordation, or issuance of a building permit, whichever comes first, the applicant or responsible party shall enter into a secured fire protection agreement with OCFA Strategic Services (714-573-6199) to mitigate additional fire service impacts resulting from the project

47. Emergency Responder Digital Radio System: Emergency Responder Digital Radio System: An emergency responder digital radio system shall be provided in this structure. Refer to CFC 510 and the OCC/OCFA DAS/BDA guidelines (available at ocfa.org) for requirements. Evidence of compliance with emergency responder digital radio system design and performance criteria shall be provided prior to occupancy.

48. Traffic Pre-emption Devices: Prior to issuance of a final map, grading permit, or building permit, whichever comes first, the applicant or responsible party shall arrange with the appropriate city, county, or state public works department or agency for installation of traffic pre-emption devices on each traffic signal installed, relocated, or similarly modified as part of this project.

During grading and construction activities:

49. Accommodation for Unanticipated Cultural/Paleo Resources. If construction or grading activities result in the discovery of significant historic or prehistoric archaeological artifacts or unique paleontological resources, all work within 100 feet of the discovery shall cease, the Director of Community Development shall be notified, the resources shall be examined by a qualified archaeologist, paleontologist, or historian for appropriate protection and preservation measures; and work may only resume when appropriate protections are in place and have been approved by the Community Development Director.

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50. Public Resources Code (Human Remains). In the event that human remains are discovered, there shall be no disposition of such human remains, other than in accordance with the procedures and requirements set forth in California Health and Safety Code Section 7050.5 and Public Resources Code Section 5097.98. If human remains are discovered during any ground disturbing activity, work shall stop until the Director of Community Development and the Orange County Coroner have been contacted. If the human remains are determined to be of Native American origin, the Native American Heritage Commission and the most likely descendants shall be consulted; and work may only resume when appropriate measures have been taken and approved by the Community Development Director.

51. Noise associated with construction activities shall be limited to the hours specified in Lake Forest Municipal Code Section 11.16.080, unless otherwise exempted pursuant to Section 11.16.050.

52. During construction, the contactor shall ensure all construction equipment is equipped with mufflers and other suitable noise attenuating devices (i.e., engine shields).

53. Construction-related equipment, including heavy-duty equipment, motor vehicles and portable equipment, shall be turned off when not in use for more than 5 minutes.

The applicant shall obtain a building permit issued by the Building Division. Prior to issuance of any building permit, the following shall be completed:

54. A Building Permit will be required. To obtain the building permit, please submit three sets of drawings prepared by an architect or engineer, structural calculations prepared by the engineer, soils report prepared by a soils engineer, Energy analysis (T-24), along with building, electrical, mechanical, and plumbing permit applications and the pdf files to the Building Division.

55. Approvals shall be obtained from the following outside agencies:
a. OCFA
b. Irvine Ranch Water District (IRWD)
c. Orange County Health Care Agency
d. Air Quality Management District

56. All applicable development impact fees shall be paid to the appropriate agency.

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SDP 05-25-5800 & UP 05-25-5803 (Costco Wholesale) Agenda of March 17, 2026

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57. All signage shall be subject to a separate building permit.

Prior to the final of building permits/issuance of a Certificate of Occupancy, the following shall be completed:

58. The applicant shall ensure that mechanical equipment placed on the roof, such as, but not limited to, air conditioning, heating, ventilating ducts, and exhaust fans are screened from view per the approved plans. (PLNG)

59. The applicant shall submit a letter of certification to the Director of Community Development from the project architect certifying that all improvements have been constructed in accordance with the approved plans. Determination of consistency shall be subject to the review and approval of the Director of Community Development. (PLNG)

60. The applicant shall install the landscaping and irrigation in accordance with the approved landscape plans. The applicant shall submit a landscape installation verification letter to the Director of Community Development from a licensed landscape architect indicating that the landscaping for the project was installed in accordance with the approved plan. (PLNG)

61. In accordance the City’s Water Efficient Landscape Guidelines, the landscape architect shall submit a completed and signed “Landscape Installation Certificate of Completion” for all the landscaping at the site. As detailed in the certificate, the following items shall also be completed:
a. Irrigation scheduling parameters used to set the controller; b. Landscape and irrigation maintenance schedule;
c. Irrigation audit report; and
d. Soil analysis report, if not submitted with Landscape Documentation Package, and documentation verifying implementation of the soil report recommendations. (PLNG)
The use shall be operated and maintained in substantial conformance with the following:

62. The project shall be developed and maintained in substantial compliance with the plans approved by the City Council on March 17, 2026, and on file with the City of Lake Forest Community Development Department. Minor modification or changes to these plans shall be subject to the additional review as determined by the Community Development Director.

63. All landscaping shall be maintained in a healthy and living condition. If necessary, plants shall be replaced in a manner that is consistent with the Item: 11
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Resolution
SDP 05-25-5800 & UP 05-25-5803 (Costco Wholesale) Agenda of March 17, 2026

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approved landscaping plan. Landscaping shall be irrigated and all irrigation systems shall be maintained in good working order.

64. All seasonal sales occurring outside shall be limited to the seasonal sale area as identified on the plans approved by the City Council on March 17, 2026. Seasonal sales shall occur for no more than 30 days at a time, with a minimum of 14 calendar days between any successive seasonal sale. The site shall be returned to its previous condition upon the termination of the seasonal sale. (PLNG)
PASSED, APPROVED AND ADOPTED this 17th day of March 2026, by the following vote, to wit:
____________________
ROBERT PEQUEÑO
MAYOR
ATTEST:
_______________________

THY MERRITT

CITY CLERK
APPROVED AS TO FORM:
__________________________
MATTHEW E. RICHARDSON

CITY ATTORNEY

STATE OF CALIFORNIA )

COUNTY OF ORANGE ) SS

CITY OF LAKE FOREST )
I, Thy Merritt, City Clerk of the City of Lake Forest, California, do hereby certify that the foregoing Resolution No. 2026-__ was duly passed and adopted at a regular meeting Item: 11
535
Resolution
SDP 05-25-5800 & UP 05-25-5803 (Costco Wholesale) Agenda of March 17, 2026

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of the Lake Forest City Council on the 17th day of March 2026, by the following vote, to wit:

AYES: COUNCIL MEMBERS
NOES: COUNCIL MEMBERS
ABSTAIN: COUNCIL MEMBERS
ABSENT: COUNCIL MEMBERS
_______________________________

THY MERRITT

CITY CLERK
Item: 11
536
ATTACHMENT 2
Item: 11
537
Resolution
UP 05-25-5801 / PCN 12-25-5850
(Costco Wholesale Alcohol Sales) Agenda of March 17, 2026

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RESOLUTION NO. 2026-__

A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF LAKE
FOREST, CALIFORNIA, APPROVING USE PERMIT 05-25-5801

AND PUBLIC CONVENIENCE OR NECESSITY DETERMINATION
12-25-5850 TO ALLOW FOR THE RETAIL SALE OF BEER, WINE,

AND DISTILLED SPIRITS FOR OFF-SITE CONSUMPTION IN
CONJUNCTION WITH A TYPE 21 LICENSE FOR COSTCO
WHOLESALE AT 26602 TOWNE CENTRE DRIVE
WHEREAS, on May 27, 2025, Costco Wholesale ("Applicant") filed a Site Development Permit application to develop a 16.3-acre parcel at 26602 Towne Centre Dr, with a retail building for Costco Wholesale including the demolition of the existing movie theater building and accompanying site improvements and constructing a new 34 ft tall, 165,068 gross sq. ft. building with associated parking, landscaping, seasonal outdoor sale and display areas, and other associated improvements (the proposed "Project”); and
WHEREAS, included with the Project application is a request for a Use Permit (UP 05-25-5801) for the retail sales of beer, wine, and distilled spirits for off site consumption in accordance with a Type 21 Department of Alcoholic Beverage Control (“ABC”) license; and
WHEREAS, ABC has determined that an overconcentration of alcohol licenses exists within the Census Tract (Tract No. 0524.22) and a Public Convenience or Necessity (“PCN”) determination is required, for which the applicant has filed a PCN request (PCN 12-25-5850) in conjunction with an application for Use Permit 05-25-5801; and
WHEREAS, the project site is zoned Mixed Use 43 (“MU 43”) within the Foothill Ranch Planned Community (“FRPC”), which permits the retail sale of alcoholic beverages subject to approval of a Use Permit; and WHEREAS, on August 4, 2015, the Lake Forest City Council adopted a Policy for the Review of Requests for Alcohol Sales for Off-Site Consumption and Determination of Public Convenience or Necessity, which, among other things, delegates to the Lake Forest Planning Commission the decision to make PCN determinations pursuant to Business and Professions Code 23958.4(b)(2); and Item: 11
538
Resolution
UP 05-25-5801 / PCN 12-25-5850
(Costco Wholesale Alcohol Sales) Agenda of March 17, 2026

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WHEREAS, on February 5, 2026, the Planning Commission conducted a duly-noticed public hearing to consider Use Permit 05-25-5801 and Public Convenience or Necessity 12-25-5850, and approved the Project; and WHEREAS, an appeal was subsequently filed by Lozeau Drury LLP on behalf of the Supporters Alliance for Environmental Responsibility (“SAFER”); and
WHEREAS, the City gave notice of the public hearing at which the project would be considered by the City Council by publishing a notice in a newspaper of general circulation and by posting a notice at City Hall on March 5, 2026; and WHEREAS, on March 17, 2026, the City Council conducted a duly-noticed public hearing to consider Use Permit 05-25-5801 and Public Convenience or Necessity 12-25-5850, at which interested persons had an opportunity to testify in support of, or opposition to the Project, and at which the City Council considered the application; and
WHEREAS, all other legal prerequisites to the adoption of this Resolution have occurred.

NOW THEREFORE, THE CITY COUNCIL OF THE CITY OF LAKE
FOREST DOES RESOLVE, DETERMINE, FIND AND ORDER AS FOLLOWS:

SECTION 1. Incorporation of Recitals. The City Council hereby finds and determines that the Recitals above are true and correct and incorporated herein.

SECTION 2. California Environmental Quality Act. Pursuant to Resolution No. 2026-07 the City Council on March 17, 2026, has adopted a CEQA exemption for the Project pursuant to Article 12 – Special Situations, Sec. 15183, Projects Consistent with a Community Plan, General Plan, or Zoning, of the CEQA Guidelines. This action taken herein relies upon that CEQA determination, and no further environmental review is required.

SECTION 3. Use Permit Findings. With regard to Use Permit 05-25- 5801, the Lake Forest City Council hereby finds, based on consideration of the whole record before it, as follows:
1) General Plan Consistency: The use or project proposed is consistent with the General Plan.

Item: 11
539
Resolution
UP 05-25-5801 / PCN 12-25-5850
(Costco Wholesale Alcohol Sales) Agenda of March 17, 2026

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The project site is designated Mixed Use 43 (“MU 43”) on the General Plan Land Use Element Map. The MU 43 designation “provides opportunities for mixtures of commercial, office, and residential uses in the same building, on the same parcel of land, or within the same area.” While the designation allows for both vertical and horizontal integration of compatible uses, single-use projects are allowed. The ancillary sale of beer, wine, and distilled spirits within the proposed retail business is a commercial use consistent with the General Plan and applicable goals and policies. 2) Zoning Code: The use, activity, or improvement(s) proposed by the application is consistent with the provisions of the Zoning Code.

The Foothill Ranch Planned Community Development Plan (“FRPC”) and Supplemental Text establishes land use and development regulations for all property within the FRPC boundaries. Properties falling within the Mixed-Use zoning designation are subject to Section 9.73 of the Lake Forest Municipal Code (“LFMC”). Pursuant to LFMC Section 9.73.065, “Alcohol Sales for Off-Site Consumption” is permitted in this zone with the approval of a Use Permit.

Additionally, LFMC Section 9.146.130 includes four findings specific to the sale of alcohol for off-site consumption. These findings are included in this resolution (Findings 8-11). Accordingly, with the approval of this Use Permit, the project is consistent with the provisions of the City’s Zoning Code.
3) CEQA: The approval of the permit application is in compliance with the requirements of the California Environmental Quality Act.

Pursuant to Resolution No. 2026-07, the City Council on March 17, 2026, adopted a CEQA exemption for the Project pursuant to Article 12 – Special Situations, Sec. 15183, Projects Consistent with a Community Plan, General Plan, or Zoning, of the CEQA Guidelines. This action taken herein relies upon that CEQA determination, and no further environmental review is required.
4) Compatibility: The location, size, design and operating characteristics of the proposed use will not create significant noise, traffic or other conditions or situations that may be objectionable, detrimental or incompatible with other permitted uses in the vicinity.

The proposed sale of alcohol would occur in the Costco Wholesale business, which would be located in an already developed regional Item: 11
540
Resolution
UP 05-25-5801 / PCN 12-25-5850
(Costco Wholesale Alcohol Sales) Agenda of March 17, 2026

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shopping center containing various commercial and office uses. The proposed alcohol display area would comprise approximately 1% of the total floor sales area of the business and be ancillary to the business offerings, which include groceries, household items, clothing, hot and cold prepared foods, pharmacy and medical offerings, and automotive needs.

Site layout, including building design and site circulation, was reviewed under SDP 05-25-5800 and determined that the Project would not create significant noise, traffic, or other conditions or situations that may be objectionable, detrimental or incompatible with other permitted uses in the vicinity.
5) General Welfare: The application will not result in conditions or circumstances contrary to the public health and safety and the general welfare.

The proposed sale of alcohol would occur inside the building. Building design and site circulation in accordance with the Citywide Design Guidelines was reviewed under SDP 05-25-5800 and found to consistent with the purpose and intent of the guidelines.
8) Nuisance Activities: The sale of alcohol for off-site consumption, as part of the operation of the business, will not result in nuisance activities within the premises or in close proximity to the premises.

Based on a review of the proposed alcohol sales by the Chief of Police Services, the proposed use would not cause an increase in need for law enforcement services or contribute to a current law enforcement problem Item: 11
541
Resolution
UP 05-25-5801 / PCN 12-25-5850
(Costco Wholesale Alcohol Sales) Agenda of March 17, 2026

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in the area. Therefore, it is not expected that the sale of alcohol would result in nuisance activities.
9) Law Enforcement: The sale of alcohol for off-site consumption, as part of the operation of the business, will not create a need to change any operational requirements or staffing of law enforcement personnel.

Based on the Report of the Chief of Police Services, the proposed use is not expected to cause an increase in need for law enforcement services or contribute to a current law enforcement problem in the area. The proposed Costco Wholesale is in the Orange County Sheriff’s Department internal response area (IRA) LF52. According to the Report of the Chief of Police Services, 0% of the reported crimes in 2024 in IRA LF52 were alcohol violations of law.

In addition, the store is only open for Costco members and includes security measures such as extensive security cameras, verification of legal age prior to the sale of alcoholic beverages, and employee training. 10) Physical Design and Layout: The physical design and layout of the business floor plan and associated parking area will not create loitering, noise, traffic, or other conditions or situations that may be detrimental or incompatible with other businesses in the adjacent area or permitted uses in the vicinity.

The alcohol display area will comprise approximately 1.10% of the total sales floor area. Both the entry and exit points of the store are monitored by employees and security cameras will be installed throughout the store.

Once constructed, the Costco Wholesale will be located within a large, active shopping center with sufficient parking lot lighting and site circulation. Accordingly, no detrimental or incompatible conditions are anticipated.
11) Management Standards: The proposed management standards, training, and site supervision of the business will deter loitering, noise, traffic, and other conditions or situations that may be detrimental or incompatible with other businesses in the adjacent area or permitted uses in the vicinity.

Use Permit 05-25-5801 and PCN 12-25-5850 will be subject to numerous conditions designed to minimize any potential detrimental impacts, including a requirement for employee training pertaining to alcohol sales, and restricting the alcohol sales area to the approved floor plan.

Item: 11
542
Resolution
UP 05-25-5801 / PCN 12-25-5850
(Costco Wholesale Alcohol Sales) Agenda of March 17, 2026

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SECTION 4. Public Convenience or Necessity Findings. With regard to PCN 12-25-5850, the Lake Forest City Council hereby finds, based on consideration of the whole record before it, as follows:
1) The sale of alcohol at an additional location within the Census Tract will allow the consumer to purchase alcohol in conjunction with other specialty goods or services desired by the consumer at the business location.

Costco is a membership only retail business that offers a variety of products in bulk quantities in a consolidated shopping environment for its members. The sale of alcohol at this location would allow members to complete their shopping needs in a single environment which includes groceries, household items, clothing, hot and cold prepared foods, pharmacy and medical offerings, and automotive needs.
2) The business will offer a unique product in terms of price, quality, variety, or hours which are not readily available in the local area.

As a wholesale membership only establishment, Costco would offer a variety of alcoholic beverages at a value to its members. A variety of beverages are typically sold at Costco, including seasonal and bulk quantity packages in a consolidated shopping environment for its members.
3) If proposed in conjunction with another primary use, the sale of alcohol will be ancillary to the primary business operations.

The proposed alcohol sales areas would constitute approximately 1.10% of the floor area (1,765 sq. ft.) of the overall 160,942 sq. ft. sales area, which would be ancillary to the various other groceries, goods, and services Costco would offer at the location. Due to the small percentage of floor area and wide variety of other goods and services offered, the sale of alcohol is clearly ancillary to the primary business operation.

SECTION 5. CITY COUNCIL ACTIONS. The City Council hereby takes the following actions:
1) Approves Use Permit 05-25-5801 to allow for alcohol sales at Costco Wholesale to be located at 26602 Towne Centre Drive, subject to the following conditions.

Item: 11
543
Resolution
UP 05-25-5801 / PCN 12-25-5850
(Costco Wholesale Alcohol Sales) Agenda of March 17, 2026

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2) Approves a determination of Public Convenience or Necessity for a Type 21 Alcoholic Beverage Control license for Costco Wholesale to be located at 26602 Towne Centre Drive.
3) Directs staff to forward a copy of this Resolution to the California Department of Alcoholic Beverage Control.

CONDITIONS OF APPROVAL
UP 05-25-5801 and PCN 12-25-5850
The following conditions of approval shall apply to the Applicant, developer and/or property owner, whichever is appropriate for the condition.

1. Indemnification: The applicant shall indemnify, protect, defend, and hold the City, and/or any of its officials, officers, employees, agents, departments, agencies, and instrumentalities thereof, harmless from any and all claims, demands, lawsuits, writs of mandamus, and other actions and proceedings (whether legal, equitable, declaratory, administrative or adjudicatory in nature), and alternative dispute resolution procedures (including, but not limited to arbitrations, mediations, and other such procedures), judgments, orders, and decisions (collectively “Actions”), brought against the City, and/or any of its officials, officers, employees, agents, departments, agencies, and instrumentalities thereof, that challenge, attack, or seek to modify, set aside, void, or annul, any action of, or any permit or approval issued by the City and/or any of its officials, officers, employees, agents, departments, agencies, and instrumentalities thereof (including actions approved by the voters of the City) for or concerning the project, whether such Actions are brought under the Ralph M. Brown Act, California Environmental Quality Act, the Planning and Zoning Law, the Subdivision Map Act, Community Redevelopment Law, Code of Civil Procedure Sections 1085 or 1094.5, or any other federal, state, or local constitution, statute, law, ordinance, charter, rule, regulation, or any decision of a court of competent jurisdiction. It is expressly agreed that the City shall have the right to approve, which approval will not be unreasonably withheld, the legal counsel providing the City’s defense, and that applicant shall reimburse City for any costs and expenses directly and necessarily incurred by the City in the course of the defense.

City shall promptly notify the applicant of any Action brought and City shall cooperate with applicant in the defense of the Action.

2. Expiration: Use Permit No. 05-25-5801 shall expire 24 months from the date of approval if building permits for the project have not been issued and an Item: 11
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Resolution
UP 05-25-5801 / PCN 12-25-5850
(Costco Wholesale Alcohol Sales) Agenda of March 17, 2026

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extension of time has not been approved by the Director of Community Development.

The use shall be operated and maintained in compliance with the following:

4. The project shall be developed and maintained in substantial compliance with the project description, security measures and floor plans approved by the City Council and on file with the City of Lake Forest Community Development Department, except as modified by conditions of approval contained herein.

5. Prior to the sale of alcoholic beverages, the business owner must obtain, and then maintain, a Type 21 ABC license as required by the California Department of Alcoholic Beverage Control.

6. The business owner shall comply with all rules, regulations and conditions of the required alcohol licenses and the California Department of Alcoholic Beverage Control, as well as all applicable federal, state, and local laws.

7. There shall be no exterior advertising, promoting, or indicating the availability of alcoholic beverages at the business. Interior displays of alcoholic beverages or signs which are clearly visible to the exterior shall constitute a violation of this condition.

8. There shall be no change to the location(s) of the alcoholic beverages display(s) as shown on the approved floor plan without approval from the Chief of Police Services and Director of Community Development. Any major changes to the location of the alcoholic beverages, as determined by the Chief of Police Services or the Director of Community Development, may require an amendment to the approved Use Permit.

Item: 11
545
Resolution
UP 05-25-5801 / PCN 12-25-5850
(Costco Wholesale Alcohol Sales) Agenda of March 17, 2026

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9. The floor area dedicated to the display of alcohol shall not exceed 1.10% of the total floor area of the tenant space. Any increase requires an amendment to the approved Use Permit.

10. In the event security problems occur at the business, and at the request of the Chief of Police Services, the business owner, at his/her own expense, shall provide an amended security plan with additional security provisions as determined by the Chief of Police Services. The additional security provisions may include, but are not limited to, interior and exterior security cameras, additional lighting, posted signs and/or security guards. Nonmitigatable security problems directly related to the sale of alcohol may be cause for revocation of this Use Permit.

11. All required/approved digital recording camera equipment shall be in place and in good working order at all times. Video recordings from the equipment shall be submitted to the Chief of Police Services, upon request by the Chief, within 72 hours.

12. The possession of alcoholic beverages in open containers and/or the consumption of alcoholic beverages are prohibited within the subject premises and outdoor public areas surrounding the premises, including but not limited to, the parking lot.

13. All employees of the business involved in the sales of alcoholic beverages shall complete training from the State of California Department of Alcoholic Beverage Control (ABC) Leadership and Education in Alcohol and Drugs (LEAD) Program or an ABC-accepted equivalent program. The business shall maintain certificates of completion of the course for each employee at the site and provide the certificates to the City upon request.

14. The business owner shall post and maintain a professional-quality sign facing the premises parking lot in substantially the following form:
“Possession of unsealed or open containers of ALCOHOLIC BEVERAGES in this parking area or any public street or sidewalk is prohibited and is subject to criminal prosecution and a fine.” The sign shall conform to the provisions of Lake Forest Municipal Code Section 11.40.030.

PASSED, APPROVED AND ADOPTED this 17th day of March 2026, by the following vote, to wit:

Item: 11
546
Resolution
UP 05-25-5801 / PCN 12-25-5850
(Costco Wholesale Alcohol Sales) Agenda of March 17, 2026

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____________________
ROBERT PEQUEÑO
MAYOR
ATTEST:
_______________________

THY MERRITT

CITY CLERK
APPROVED AS TO FORM:
__________________________
MATTHEW E. RICHARDSON

CITY ATTORNEY

STATE OF CALIFORNIA )

COUNTY OF ORANGE ) SS

CITY OF LAKE FOREST )
I, Thy Merritt, City Clerk of the City of Lake Forest, California, do hereby certify that the foregoing Resolution No. 2026-__ was duly passed and adopted at a regular meeting of the Lake Forest City Council on the 17th day of March 2026, by the following vote, to wit:

AYES: COUNCIL MEMBERS
NOES: COUNCIL MEMBERS
ABSTAIN: COUNCIL MEMBERS
ABSENT: COUNCIL MEMBERS
_______________________________

THY MERRITT

CITY CLERK
Item: 11
547
ATTACHMENT 3
Item: 11
548
Resolution
UP 05-25-5802
(Costco Wholesale Light Auto Repair) Agenda of March 17, 2026

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RESOLUTION NO. 2026-__

A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF LAKE
FOREST, CALIFORNIA, APPROVING USE PERMIT 05-25-5802

TO ALLOW FOR LIGHT AUTOMOTIVE REPAIR IN THE TIRE
CENTER FOR COSTCO WHOLESALE AT 26602 TOWNE

CENTRE DRIVE
WHEREAS, on May 27, 2025, Costco Wholesale ("Applicant") filed a Site Development Permit application to develop a 16.3-acre parcel at 26602 Towne Centre Dr, with a retail building for Costco Wholesale including the demolition of the existing movie theater building and accompanying site improvements and constructing a new 34 ft tall, 165,068 gross sq. ft. building with associated parking, landscaping, seasonal outdoor sale and display areas, and other associated improvements (the proposed "Project”); and
WHEREAS, included with the Project application is a request for a Use Permit (UP 05-25-5802) to allow for light automotive repair in the tire center; and WHEREAS, the project site is zoned Mixed Use 43 (“MU 43”) within the Foothill Ranch Planned Community (“FRPC”), which permits light automotive repair subject to approval of a Use Permit; and
WHEREAS, on February 5, 2026, the Planning Commission conducted a duly-noticed public hearing to consider Use Permit 05-25-5802, and approved the Project; and
WHEREAS, an appeal was subsequently filed by Lozeau Drury LLP on behalf of the Supporters Alliance for Environmental Responsibility (“SAFER”); and
WHEREAS, the City gave notice of the public hearing at which the project would be considered by the City Council by publishing a notice in a newspaper of general circulation and by posting a notice at City Hall on March 5, 2026; and WHEREAS, on March 17, 2026, the City Council conducted a duly-noticed public hearing to consider Use Permit 05-25-5802, at which interested persons had an opportunity to testify in support of, or opposition to the Project, and at which the City Council considered the application; and
Item: 11
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Resolution
UP 05-25-5802
(Costco Wholesale Light Auto Repair) Agenda of March 17, 2026

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WHEREAS, all other legal prerequisites to the adoption of this Resolution have occurred.

NOW THEREFORE, THE CITY COUNCIL OF THE CITY OF LAKE
FOREST DOES RESOLVE, DETERMINE, FIND AND ORDER AS FOLLOWS:

SECTION 1. Incorporation of Recitals. The City Council hereby finds and determines that the Recitals above are true and correct and incorporated herein.

SECTION 3. Use Permit Findings. With regard to Use Permit 05-25- 5802, the Lake Forest City Council hereby finds, based on consideration of the whole record before it, as follows:
1) General Plan Consistency: The use or project proposed is consistent with the General Plan.

The project site is designated Mixed Use 43 (“MU 43”) on the General Plan Land Use Element Map. The MU 43 designation “provides opportunities for mixtures of commercial, office, and residential uses in the same building, on the same parcel of land, or within the same area.” While the designation allows for both vertical and horizontal integration of compatible uses, single-use projects are allowed. The establishment includes a designated area within the proposed retail business for tire and other light automotive services which are a commercial use consistent with the General Plan and applicable goals and policies.
2) Zoning Code: The use, activity, or improvement(s) proposed by the application is consistent with the provisions of the Zoning Code.

The Foothill Ranch Planned Community Development Plan (“FRPC”) and Supplemental Text establishes land use and development regulations for all property within the FRPC boundaries. Properties falling within the Mixed-Use zoning designation are subject to Section 9.73 of the Lake Forest Municipal Code (“LFMC”). Pursuant to LFMC Section 9.73.065, Item: 11
550
Resolution
UP 05-25-5802
(Costco Wholesale Light Auto Repair) Agenda of March 17, 2026

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“Light Automotive Repair” is permitted in this zone with the approval of a Use Permit. Accordingly, with the approval of this Use Permit, the project is consistent with the provisions of the City’s Zoning Code. 3) CEQA: The approval of the permit application is in compliance with the requirements of the California Environmental Quality Act.

The proposed automotive repair services would occur in the designated tire center of the Costco Wholesale retail building, which would be located in an already developed regional shopping center containing various commercial and office uses. The light automotive repair services would primarily be limited to the sale, installation, and maintenance of vehicle tires and do not include other services like oil changes and engine tuning.

Item: 11
551
Resolution
UP 05-25-5802
(Costco Wholesale Light Auto Repair) Agenda of March 17, 2026

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6) Development Fees for Provision of Public Facilities:

The proposed light automotive repair would occur within the tire center along the east elevation of the building. Building design and site circulation in accordance with the Citywide Design Guidelines was reviewed under SDP 05-25-5800 and found to consistent with the purpose and intent of the guidelines.

SECTION 4. CITY COUNCIL ACTIONS. The City Council hereby takes the following actions:
1) Approves Use Permit 05-25-5802 to allow for light automotive repair at Costco Wholesale to be located at 26602 Towne Centre Drive, subject to the following conditions.

CONDITIONS OF APPROVAL
UP 05-25-5802
The following conditions of approval shall apply to the Applicant, developer and/or property owner, whichever is appropriate for the condition.

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brought under the Ralph M. Brown Act, California Environmental Quality Act, the Planning and Zoning Law, the Subdivision Map Act, Community Redevelopment Law, Code of Civil Procedure Sections 1085 or 1094.5, or any other federal, state, or local constitution, statute, law, ordinance, charter, rule, regulation, or any decision of a court of competent jurisdiction. It is expressly agreed that the City shall have the right to approve, which approval will not be unreasonably withheld, the legal counsel providing the City’s defense, and that applicant shall reimburse City for any costs and expenses directly and necessarily incurred by the City in the course of the defense.

City shall promptly notify the applicant of any Action brought and City shall cooperate with applicant in the defense of the Action.

2. Expiration: Use Permit No. 05-25-5802 shall expire 24 months from the date of approval if building permits for the project have not been issued and an extension of time has not been approved by the Director of Community Development.

The use shall be operated and maintained in compliance with the following:

4. The project shall be developed and maintained in substantial compliance with the project description and plans approved by the City Council and on file with the City of Lake Forest Community Development Department, except as modified by conditions of approval contained herein.

PASSED, APPROVED AND ADOPTED this 17th day of March, 2026, by the following vote, to wit:

Item: 11
553
Resolution
UP 05-25-5802
(Costco Wholesale Light Auto Repair) Agenda of March 17, 2026

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____________________
ROBERT PEQUEÑO
MAYOR
ATTEST:
_______________________

THY MERRITT

CITY CLERK
APPROVED AS TO FORM:
__________________________
MATTHEW E. RICHARDSON

CITY ATTORNEY

STATE OF CALIFORNIA )

COUNTY OF ORANGE ) SS

CITY OF LAKE FOREST )
I, Thy Merritt, City Clerk of the City of Lake Forest, California, do hereby certify that the foregoing Resolution No. 2026-__ was duly passed and adopted at a regular meeting of the Lake Forest City Council on the 17th day of March, 2026, by the following vote, to wit:

AYES: COUNCIL MEMBERS
NOES: COUNCIL MEMBERS
ABSTAIN: COUNCIL MEMBERS
ABSENT: COUNCIL MEMBERS
_______________________________

THY MERRITT

CITY CLERK
Item: 11
554
ATTACHMENT 4
Item: 11
555
Resolution
PSP 05-25-5804
(FRTC Phase 4 PSP Amendments) Agenda of March 17, 2026

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RESOLUTION NO. 2026-__

A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF LAKE

FOREST, CALIFORNIA, APPROVING PLANNED SIGN
PROGRAM 05-25-5804, MODIFYING THE EXISTING PLANNED
SIGN PROGRAM APPROVED UNDER PSP 10-17-5094 FOR
PHASE 4 OF THE FOOTHILL RANCH TOWNE CENTRE (26562-
26672 TOWNE CENTRE DRIVE)
WHEREAS, on January 14, 2026, Todd Travis, with Travis Design Group, on behalf of the Foothill Business Association, filed an application for a planned sign program (“PSP”) for amendments to the existing PSP in effect for Phase 4 of the Foothill Ranch Towne Centre; and
WHEREAS, the Municipal Code allows a PSP to assure coordination and compatibility between all signs within a commercial center and amendments to a PSP shall be processed in the same manner as an original application; and WHEREAS, the PSP in effect was most recently approved by the Planning Commission on December 14, 2017, under application PSP 10-17-5094; and WHEREAS, on February 5, 2026, the Planning Commission conducted a duly-noticed public hearing to consider Planned Sign Program 05-25-5804, and approved the Project; and
WHEREAS, an appeal was subsequently filed by Lozeau Drury LLP on behalf of the Supporters Alliance for Environmental Responsibility (“SAFER”); and
WHEREAS, the City gave notice of the public hearing at which the project would be considered by the City Council by publishing a notice in a newspaper of general circulation and by posting a notice at City Hall on March 5, 2026; and WHEREAS, on March 17, 2026, the City Council conducted a duly-noticed public hearing to consider Planned Sign Program 05-25-5804, at which interested persons had an opportunity to testify in support of, or opposition to the Project, and at which the City Council considered the application; and WHEREAS, all other legal prerequisites to the adoption of this Resolution have occurred.

Item: 11
556
Resolution
PSP 05-25-5804
(FRTC Phase 4 PSP Amendments) Agenda of March 17, 2026

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NOW THEREFORE, THE CITY COUNCIL OF THE CITY OF LAKE
FOREST DOES RESOLVE, DETERMINE, FIND AND ORDER AS FOLLOWS:

SECTION 1. Incorporation of Recitals. The City Council hereby finds and determines that the Recitals above are true and correct and incorporated herein.

SECTION 2. California Environmental Quality Act. Pursuant to Resolution No. 2026-07, the City Council on March 17, 2026, has adopted a CEQA exemption for the Project pursuant to Article 12 – Special Situations, Sec. 15183, Projects Consistent with a Community Plan, General Plan, or Zoning, of the CEQA Guidelines. This action taken herein relies upon that CEQA determination, and no further environmental review is required.

SECTION 3. Planned Sign Program Findings. With regard to Planned Sign Program 05-25-5804, the Lake Forest City Council hereby finds, based on consideration of the whole record before it, as follows:
1) The Planned Sign Program achieves overall design and sign integration that exceeds what would have been achieved through sole implementation of the Sign Ordinance.

The amendments to the Planned Sign Program expand the applicability to cover major tenants occupying a gross-floor area greater than or equal to 25,000 sq. ft. The amendments further ensure that all signs on the site will be aesthetically consistent, and that wall signs will be properly spaced and comply with limitations based on the total number of signs, their size, number of lines of text, and illumination. Accordingly, the Planned Sign Program achieves overall design and sign integration that exceeds what would have been achieved through sole implementation of the Sign Ordinance
2) The proposed Planned Sign Program sign(s) will harmonize with other onsite signs and enhance the site, building, and/or use on the site.

The existing Planned Sign Program are limited to signage for businesses falling under the major tenant classification, which at present is limited to only those occupying 25,000 sq. ft. up to 120,000 sq. ft. The proposed amendments would expand the applicability of the Planned Sign Program to any tenant occupying a gross floor area greater than or equal to 25,000 sq. ft. and establish sign criteria proportionate to the larger building size.

Item: 11
557
Resolution
PSP 05-25-5804
(FRTC Phase 4 PSP Amendments) Agenda of March 17, 2026

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The Planned Sign Program wall sign regulations will still ensure that the tenant signage is consistent with the architectural character for each building type in the shopping center. Accordingly, the proposed sign regulations will ensure that tenant signs will enhance and harmonize with other tenants’ signs.
3) The proposed sign(s) will not negatively impact the aesthetics of the subject site or the surrounding properties.

The Planned Sign Program will ensure that new signage for major tenants occupying a building area in excess of 25,000 sq. ft. will be compatible with the architectural character of the buildings at the Foothill Ranch Towne Centre Shopping Center. The proposed regulations will provide for signs that are appropriate in size and number for the corresponding tenant/building classification. Accordingly, the proposed signs will not negatively impact the aesthetics of the subject site or the surrounding properties.
4) The proposed sign(s) are consistent with the purpose and intent of the Sign Ordinance.

This Planned Sign Program is consistent with the purpose and intent of the City’s Sign Ordinance, in that it amends the existing Planned Sign Program regulations to provide for the effective use wall signs, as a means of identification and communication for the tenants in the Foothill Ranch Towne Centre, occupying a building area in excess of 25,000 sq. ft..

Moreover, the Planned Sign Program permits only signs that will not, by reason of their size, location, construction or manner of display, endanger the public safety. Therefore, the proposed signs are consistent with the purpose and intent of the Sign Ordinance.
5) The signs are consistent with the purpose and intent of all applicable design guidelines.

Currently, the City has no adopted design guidelines specific to signage for this location.

SECTION 4. CITY COUNCIL ACTIONS. The City Council hereby takes the following actions:
1) Rescind approval of Planned Sign Program 10-14-5094.

Item: 11
558
Resolution
PSP 05-25-5804
(FRTC Phase 4 PSP Amendments) Agenda of March 17, 2026

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2) Approve Planned Sign Program 05-25-5804, subject to the following conditions:

CONDITIONS OF APPROVAL
PSP 05-25-5804
The following conditions of approval shall apply to the Applicant, developer and/or property owner, whichever is appropriate for the condition.

1. Indemnification: The applicant shall indemnify, protect, defend, and hold the City, and/or any of its officials, officers, employees, agents, departments, agencies, and instrumentalities thereof, harmless from any and all claims, demands, lawsuits, writs of mandamus, and other actions and proceedings (whether legal, equitable, declaratory, administrative or adjudicatory in nature), and alternative dispute resolution procedures (including, but not limited to arbitrations, mediations, and other such procedures), judgments, orders, and decisions (collectively “Actions”), brought against the City, and/or any of its officials, officers, employees, agents, departments, agencies, and instrumentalities thereof, that challenge, attack, or seek to modify, set aside, void, or annul, any action of, or any permit or approval issued by the City and/or any of its officials, officers, employees, agents, departments, agencies, and instrumentalities thereof (including actions approved by the voters of the City) for or concerning the project, whether such Actions are brought under the Ralph M. Brown Act, California Environmental Quality Act, the Planning and Zoning Law, the Subdivision Map Act, Community Redevelopment Law, Code of Civil Procedure Sections 1085 or 1094.5, or any other federal, state, or local constitution, statute, law, ordinance, charter, rule, regulation, or any decision of a court of competent jurisdiction. It is expressly agreed that the City shall have the right to approve, which approval will not be unreasonably withheld, the legal counsel providing the City’s defense, and that applicant shall reimburse City for any costs and expenses directly and necessarily incurred by the City in the course of the defense.

City shall promptly notify the applicant of any Action brought and City shall cooperate with applicant in the defense of the Action.

2. The Planning Division processes discretionary applications on a deposit basis. Deposit funds are provided by applicants/developers to cover the actual costs associated with staff time and resources utilized in processing an application. If, at any time, the cost to process the application exceeds the deposit on file, additional funds shall be deposited by the Project Applicant/Developer. A final accounting for this project will be prepared Item: 11
559
Resolution
PSP 05-25-5804
(FRTC Phase 4 PSP Amendments) Agenda of March 17, 2026

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following the City Council’s decision on the project and if needed, a request for additional funds will be provided to the Project Applicant/Developer.

3. All applicable building and electrical permits shall be obtained prior to the installation of signage.

PASSED, APPROVED AND ADOPTED this 17th day of March, 2026, by the following vote, to wit:
____________________
ROBERT PEQUEÑO
MAYOR
ATTEST:
_______________________

THY MERRITT

CITY CLERK
APPROVED AS TO FORM:
__________________________
MATTHEW E. RICHARDSON

CITY ATTORNEY

STATE OF CALIFORNIA )

COUNTY OF ORANGE ) SS

CITY OF LAKE FOREST )
Item: 11
560
Resolution
PSP 05-25-5804
(FRTC Phase 4 PSP Amendments) Agenda of March 17, 2026

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I, Thy Merritt, City Clerk of the City of Lake Forest, California, do hereby certify that the foregoing Resolution No. 2026-__ was duly passed and adopted at a regular meeting of the Lake Forest City Council on the 17th day of March, 2026, by the following vote, to wit:

AYES: COUNCIL MEMBERS
NOES: COUNCIL MEMBERS
ABSTAIN: COUNCIL MEMBERS
ABSENT: COUNCIL MEMBERS
_______________________________

THY MERRITT

CITY CLERK
Item: 11
561
Attachment 5
Item: 11
562
ATTACHMENT 5 - PC REPORT
Planning Commission Agenda Report
Meeting Date: February 5, 2026
Department: Community Development
INITIATED BY: Connor Musler, AICP, Associate Planner
SUBMITTED BY: Gayle Ackerman, AICP, Director of Community Development REVIEWED BY: Amy Stonich, AICP, Assistant Director of Community Development
SUBJECT: DEMOLITION OF THE EXISTING THEATER BUILDING

AND SITE IMPROVEMENTS AND CONSTRUCTION OF A
NEW COSTCO WHOLESALE RETAIL BUILDING AT 26602

TOWNE CENTRE DRIVE
EXECUTIVE SUMMARY:

This application is a request for a new Costco Wholesale in the Foothill Ranch Towne Centre at 26602 Towne Centre Drive. The project proposal includes demolishing the existing movie theater building, formerly occupied by Regal/Cinemark, and associated site improvements and constructing a new 34- foot tall, 165,068 sq. ft. building (SDP 05-25-5800) with alcoholic beverage sales for off-site consumption (UP 05-25-5801 and PCN 12-25-5850), light auto repair in the tire center (UP 05-25-5802), requests for exceptions to the mixed-use development regulations (UP 05-25-5803), and a Planned Sign Program (PSP 05- 25-5804) to amend the existing Phase 4 PSP regulations.

Figure 1 : Front Entrance Rendering
Item: 11
563
ATTACHMENT 5 - PC REPORT
PC Agenda Report – February 5, 2026
SDP 05-25-5800, UP 05-25-5801, UP 05-25-5802, UP 05-25-5803, PSP 05-25- 5804, PCN 12-25-5850 (Costco Wholesale)
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SITE INFORMATION:

Site Address 26602 Towne Centre Drive
Applicant/Agent
Michael Okuma, Costco Wholesale
Todd Travis, Travis Design Group (for PSP
amendment)
Property Owner Costco Wholesale Corporation
General Plan Designation Mixed Use 43
Zoning District Mixed Use 43 (MU 43) within the Foothill Ranch Planned Community (FRPC)
Surrounding Area
Land Uses Zoning
North: PetSmart and Walmart MU 43 in FRPC
South: Food Festival and Offices MU 43 in FRPC
East: Chuck E. Cheese, Chipotle MU 43 in FRPC
West: SR-241 and office/industrial
buildings across SR-241
SR-241 and Urban Activity in the
Baker Ranch Planned Community
Location Map
Item: 11
564
ATTACHMENT 5 - PC REPORT
PC Agenda Report – February 5, 2026
SDP 05-25-5800, UP 05-25-5801, UP 05-25-5802, UP 05-25-5803, PSP 05-25- 5804, PCN 12-25-5850 (Costco Wholesale)
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RECOMMENDED ACTION(S):

1. Find that the project is exempt pursuant to Article 12 – Special Situations, Sec. 15183, Projects Consistent with a Community Plan, General Plan, or Zoning, which mandates that projects which are consistent with the development density established by existing zoning, community plan, or general plan policies for which an EIR was certified shall not require additional environmental review, except as might be necessary to examine whether there are project-specific significant effects which are peculiar to the project or its site; and

2. Adopt a resolution entitled: A RESOLUTION OF THE PLANNING

COMMISSION OF THE CITY OF LAKE FOREST, CALIFORNIA, APPROVING SITE DEVELOPMENT PERMIT 05-25-5800 TO DEMOLISH THE EXISTING MOVIE THEATER BUILDING AND SITE IMPROVEMENTS AT 26602 TOWNE CENTRE DR AND CONSTRUCT A NEW 34-FT TALL, 165,068 GROSS SQ. FT.

COSTCO WHOLESALE RETAIL BUILDING TO INCLUDE SURFACE-LEVEL

PARKING, LANDSCAPING, SEASONAL OUTDOOR SALES AND DISPLAY AREAS, AND OTHER ASSOCIATED IMPROVEMENTS AND USE PERMIT 05- 25-5803 FOR EXCEPTIONS TO THE MIXED USE DEVELOPMENT

STANDARDS AND DETERMINING THE PROJECT TO BE EXEMPT FROM CEQA; and

3. Adopt a resolution entitled: A RESOLUTION OF THE PLANNING

COMMISSION OF THE CITY OF LAKE FOREST, CALIFORNIA, APPROVING USE PERMIT 05-25-5801 AND PUBLIC CONVENIENCE OR NECESSITY DETERMINATION 12-25-5850 TO ALLOW FOR THE RETAIL SALE OF BEER,

WINE, AND DISTILLED SPIRITS FOR OFF-SITE CONSUMPTION IN CONJUNCTION WITH A TYPE 21 LICENSE FOR COSTCO WHOLESALE AT 26602 TOWNE CENTRE DRIVE; and

4. Adopt a resolution entitled: A RESOLUTION OF THE PLANNING

COMMISSION OF THE CITY OF LAKE FOREST, CALIFORNIA, APPROVING USE PERMIT 05-25-5802 TO ALLOW FOR LIGHT AUTOMOTIVE REPAIR IN THE TIRE CENTER FOR COSTCO WHOLESALE AT 26602 TOWNE CENTRE DRIVE; and

5. Adopt a resolution entitled: A RESOLUTION OF THE PLANNING

COMMISSION OF THE CITY OF LAKE FOREST, CALIFORNIA, APPROVING PLANNED SIGN PROGRAM 05-25-5804, MODIFYING THE EXISTING PLANNED SIGN PROGRAM APPROVED UNDER PSP 10-17-5094 FOR PHASE 4 OF THE FOOTHILL RANCH TOWNE CENTRE (26562-26672 TOWNE CENTRE DRIVE).

Item: 11
565
ATTACHMENT 5 - PC REPORT
PC Agenda Report – February 5, 2026
SDP 05-25-5800, UP 05-25-5801, UP 05-25-5802, UP 05-25-5803, PSP 05-25- 5804, PCN 12-25-5850 (Costco Wholesale)
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BACKGROUND:

The subject property is presently developed with a movie theater building and associated site improvements. Originally developed in 1999 for Regal Cinemas, the building was most recently occupied by Cinemark before its closure in September 2024. The building has been unoccupied since then.

The property is located within Phase 4 of the larger Foothill Ranch Towne Centre.

Phase 4 is generally bounded by Bake Parkway, Towne Centre Drive, Market Place, and SR-241 and includes the Food Festival, multiple pad buildings, including Chipotle, Islands, and Chuck E. Cheese, and the three Towne Centre office buildings. Phase 4 was initially approved by the County of Orange under Planning Application (PA) 1998-69.

Costco Wholesale is a member-only retail business. Typical operating hours are Monday through Friday from 10:00 a.m. to 8:30 p.m., Saturdays from 9:30 a.m. to 7:00 p.m., and Sunday from 10:00 a.m. to 6:00 p.m. The store would also open at 9:00 a.m. Monday through Sunday for Executive Membership holders. Currently, the nearest Costco location to this project site is approximately 6.6 miles away in the City of Irvine at 115 Technology Drive. This proposed Costco would better serve the local community and surrounding area by offering a more convenient location in an existing shopping center.

PROJECT DESCRIPTION:

SDP 05-25-5800 is a proposal to demolish the former movie theater building, most recently occupied by Cinemark, and the accompanying site improvements and construct in its place a new Costco Wholesale retail store. The proposed store would be a maximum of 34 feet in height and have a building area of 161,295 sq. ft., with a 3,773 sq. ft. entrance canopy for a total square footage of 165,068 sq. ft.. All tenants within Phase 4 of the Foothill Ranch Towne Centre share parking facilities. A total of 2,068 parking stalls are proposed, with 913 parking stalls proposed immediately on the parcel owned by Costco. Within the retail space, a total of 160,942 sq. ft. will be dedicated to the storage and the retail sales of goods and services, including optical exams and sales, a hearing center and pharmacy, hot and cold food preparation and sales, and alcoholic beverage sales. A vehicle display area is proposed at the front of the store under the entrance canopy and a portion of the parking lot is designated for seasonal sales (i.e. Christmas trees).

The building would also include an approximately 5,065 sq. ft. tire sales and installation area, with five service bays facing east. The retail area will be accessible to Costco members only.

Item: 11
566
ATTACHMENT 5 - PC REPORT
PC Agenda Report – February 5, 2026
SDP 05-25-5800, UP 05-25-5801, UP 05-25-5802, UP 05-25-5803, PSP 05-25- 5804, PCN 12-25-5850 (Costco Wholesale)
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Access to the site will primarily be made from the existing signalized intersections at Towne Centre Drive and Market Place and Towne Centre Drive and Entertainment. Four truck loading bays are proposed at the south side of the building closest to SR-241. An average of ten truck deliveries is anticipated to occur on a typical weekday, with most deliveries occurring outside of regular operating hours. Figure 2 shows a portion of the proposed truck route, with receiving trucks arriving via Bake Parkway to Portola Parkway and into the site via the existing signalized intersection at Market Place. A traffic study was prepared by Kittelson and Associates for the applicant and determined that no improvements will be needed to the existing roadways or modifications to intersection turn pockets based on the anticipated traffic.

While all intersections will continue to operate above City standards for Level of Service, the applicant has agreed to contribute to the installation of traffic signal monitoring and operations infrastructure in the project vicinity. This will assist in furthering initiative SP #02 within the City’s Strategic Business Plan for 2025-2032, to provide an enhanced ability to supplement emergency responsiveness and Figure 2: Proposed Site Plan
Item: 11
567
ATTACHMENT 5 - PC REPORT
PC Agenda Report – February 5, 2026
SDP 05-25-5800, UP 05-25-5801, UP 05-25-5802, UP 05-25-5803, PSP 05-25- 5804, PCN 12-25-5850 (Costco Wholesale)
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public safety, address real-time traffic conditions, improve incident management, and address traffic safety.

Exceptions to Mixed-Use Development Standards (UP 05-25-5803):

LFMC Section 9.73.064 outlines that exceptions to the mixed-use development regulations may be requested using a Use Permit. The applicant has designed the project to incorporate as many design elements as feasible. These elements include: landscaping, canopies, and trellises along all pathways accessible to pedestrians; intermittent changes in material and color; and minor changes in building height to break up the roofline and accentuate building entrances and areas intended for signage.

However, in order to accommodate the standard Costco Wholesale store look, the applicant has requested the following exceptions, which are further discussed in the analysis section of this report:
• Open space: Non-residential development in the MU 43 zoning district shall provide a minimum of 25% of the project site as open space. The proposed landscape open space will total approximately 62,653 sq. ft. (8.8%). • Massing breaks: Minor massing breaks every 50 feet along the street frontage are required for all buildings. These minor breaks shall be a minimum depth of 12 inches and four feet wide extending the full height of the building. The applicant has incorporated design elements that emulate massing breaks, including changes of materials, architectural “pop-outs” via perforated metal paneling, and incorporated landscaping and canopies to provide variation to the façade. However, these design elements do not meet the criteria to be classified as massing breaks that comply with the mixed-use development standards.
• Vertical articulation: Rooflines are required to be vertically articulated every 50 feet along the street frontage. The applicant has incorporated roofline articulation and cornices in areas of visual interest (e.g. at areas of building ingress/egress). The distances between these areas of vertical articulation range from 20 ft to 87.5 ft in areas less accessible to the public.

The vertical articulation incorporated into the building design by the applicant does not, however, occur at consistent 50-foot intervals, thus triggering the requested exception to this requirement.

Item: 11
568
ATTACHMENT 5 - PC REPORT
PC Agenda Report – February 5, 2026
SDP 05-25-5800, UP 05-25-5801, UP 05-25-5802, UP 05-25-5803, PSP 05-25- 5804, PCN 12-25-5850 (Costco Wholesale)
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Tire Center (UP 05-25-5802):

An approximately 5,065 sq. ft. tire sales and installation area, with five service bays facing the east drive aisle is also proposed. As is typical with other Costco tire centers, the automotive services at this location will primarily be limited to the sale, installation, and maintenance of vehicle tires and not include other services like oil changes and engine tuning. Eight parking stalls are proposed to be designated as “TIRE CENTER ONLY” in the parking lot immediately adjacent to the tire center.

Patrons scheduled for tire service park in these designated spaces. For safety and traffic control purposes, only Costco tire center employees will be allowed to drive vehicles scheduled for service into the service bays. One employee will drive the vehicle while another guides the vehicle and directs traffic. Two speed humps are also proposed to be installed at the drive aisle on both sides of the tire center service bays to slow traffic.

Alcohol Sales & Public Convenience or Necessity (UP 05-25-5801/PCN 12-25- 5850):

The applicant has submitted for a Department of Alcoholic Beverage Control (ABC) Type 21 license. The display of alcoholic beverages available for purchase are proposed to occupy three aisles totaling approximately 1,765 sq. ft. of the overall 160,942 sq. ft. sales area (1.10%). The applicant has received confirmation from ABC that a “Determination of Public Convenience or Necessity” (PCN) is required due to an overconcentration of alcohol licenses within the Census Tract (Tract No. 0524.22).

The Analysis section of this report further discusses the alcohol sales and PCN provisions as it relates to the City Council “Policy for the Review of Requests for Alcohol Sales for Off-Site Consumption and Determination of Public Convenience or Necessity” and LFMC Sections 9.72.090(A) and 9.146.130 ANALYSIS:

Compliance with General Plan:

The project site is designated as Mixed Use 43 (MU 43) in the General Plan Land Use Element Map. The MU 43 designation “provides opportunities for mixtures of commercial, office, and residential uses in the same building, on the same parcel of land, or within the same area” in addition to single-use projects. Non-residential development in the MU 43 designation is subject to a maximum floor area ratio (FAR) of 1.2:1. The project FAR is 0.23:1, which is well below the General Plan maximum development intensity.

Item: 11
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ATTACHMENT 5 - PC REPORT
PC Agenda Report – February 5, 2026
SDP 05-25-5800, UP 05-25-5801, UP 05-25-5802, UP 05-25-5803, PSP 05-25- 5804, PCN 12-25-5850 (Costco Wholesale)
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Compliance with Zoning Code:

The project site is located in the Mixed Use 43 (MU-43) zoning district in the Foothill Ranch Planned Community, which requires a Site Development Permit for the development of a new commercial building. As previously mentioned, this project also includes requests for alcoholic beverage sale for off-site consumption (UP 05- 25-5801), light auto repair in the tire center (UP 05-25-5802), requests for exceptions to the mixed-use development regulations (UP 05-25-5803), and amendments to the existing Planned Sign Program (PSP 05-05-5804). As shown in Table 1, the project is in compliance with the applicable building development standards in the MU-43 district.

In addition to the MU 43 development standards outlined above in Table 1, the mixed-use regulations also include provisions for building design and articulation that apply to all mixed-use zoning districts. These building design and articulation regulations include provisions for horizontal and vertical massing breaks, architectural elements, and pedestrian-oriented features. The applicant has requested the following exceptions, as allowed by LFMC Section 9.73.064, subject to Planning Commission approval of a Use Permit:
• Open space: Non-residential development in the MU 43 zoning district shall provide a minimum of 25% of the project site as open space. The project site was originally developed in the 1990s with large areas dedicated to surface parking. Approximately 8.1% of the property is presently developed as landscape open space. Accordingly, the site does not presently have 25% of the site area dedicated to open space.

The applicant has designed the site to incorporate as much landscape open space as possible, which will include planters bordering the building, new Table 1: Applicable Building Development Standards
Zoning Development
Standards Requirement Proposed
Minimum Setbacks (measured from proposed building)
from north property line 10 feet 405 feet
from west property line 10 feet 62 feet
from east property line 10 feet 251 ft 7 in
from south property line 15 feet 63 ft 6 in
Maximum Floor Area Ratio
(FAR) 1.2:1 0.23:1
Maximum Building Height 65 feet 34 feet
Item: 11
570
ATTACHMENT 5 - PC REPORT
PC Agenda Report – February 5, 2026
SDP 05-25-5800, UP 05-25-5801, UP 05-25-5802, UP 05-25-5803, PSP 05-25- 5804, PCN 12-25-5850 (Costco Wholesale)
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site boundary landscaping, and new parking lot shade trees. Figure 3 shows the proposed landscape open space, which will total approximately 62,653 sq. ft. (8.8%), a minimal increase in landscape over what is provided on-site as presently developed. It is not feasible to meet the 25% open space requirement while maintaining the existing shared driveways and drive aisles and minimum parking requirements. As such, the applicant has requested an exception to this requirement.
• Massing breaks: Minor massing breaks every 50 feet along the street frontage are required for all buildings. These minor breaks shall be a minimum depth of 12 inches and four feet wide extending the full height of the building. Figure 4 shows the some of the incorporated design elements Figure 3: Proposed Landscape Plan
Item: 11
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ATTACHMENT 5 - PC REPORT
PC Agenda Report – February 5, 2026
SDP 05-25-5800, UP 05-25-5801, UP 05-25-5802, UP 05-25-5803, PSP 05-25- 5804, PCN 12-25-5850 (Costco Wholesale)
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that emulate massing breaks, including changes of materials, architectural “pop-outs” with perforated metal paneling, and incorporated landscaping and canopies to provide variation to the façade. However, these design elements do not meet the criteria to be classified as massing breaks that comply with the mixed-use development standards. Accordingly, the applicant has requested an exception to this requirement. • Vertical articulation: Rooflines are required to be vertically articulated every 50 feet along the street frontage. The applicant has incorporated roofline articulation and cornices in areas of visual interest (e.g. at areas of building ingress/egress). Figure 4 shows the vertical articulation proposed.

The distances between these areas of vertical articulation range from 20 ft to 60 ft apart in areas more readily accessible to the public, while those areas that are less accessible have vertical articulation ranging from 30ft to 87.5 ft apart. The vertical articulation incorporated into the building design by the applicant does not, however, occur at consistent 50-foot intervals, thus triggering the requested exception to this requirement.

The spirit and intent of the mixed-use building design and articulation regulations is to ensure development in the mixed-use zoning districts includes high quality, architecturally interesting buildings. The requested exceptions are reasonable as the applicant has incorporated design elements which break up the appearance of the building without creating a repetitive appearance of massing breaks, should the code be strictly followed. In addition, the applicant has maximized the open space on the site through landscape elements. The proposed landscaping continues the existing landscape design elements present in the Foothill Ranch Towne Centre, such as palm tree lined driveways, landscaped planters, and site boundary landscaping. The applicant’s proposed 8.8% increases the amount of landscape open space over what is on the site as presently developed while still allowing the applicant to maintain shared driveways and drive aisles and meet minimum parking requirements.

Figure 4: Elevation w/ proposed articulation
Item: 11
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ATTACHMENT 5 - PC REPORT
PC Agenda Report – February 5, 2026
SDP 05-25-5800, UP 05-25-5801, UP 05-25-5802, UP 05-25-5803, PSP 05-25- 5804, PCN 12-25-5850 (Costco Wholesale)
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Parking:

LFMC Section 9.168.080 establishes off-street parking requirements. Typical retail uses that are found in a shopping center meeting the criteria established in the City parking regulations may be parked at the shopping center ratio of 1 space for each 200 sq. ft. of gross floor area. Phase 4 of the Foothill Ranch Towne Centre, which is the area generally bounded by Bake Parkway, Towne Centre Drive, Market Place, and SR-241, meets the criteria of a shopping center. Accordingly, all uses within this phase are parked at the ratio of 1 space for every 200 sq. ft., with the exception of the three Towne Centre Office Buildings (26632, 26642, & 26672 Towne Centre Dr), which are parked at the standard office ratio of 1 space for every 250 sq. ft. of gross floor area.

All users within Phase 4 share parking facilities. Based on an ALTA survey prepared by the applicant’s civil engineer, there are presently 2,512 parking stalls available in Phase 4. Table 2 provides a breakdown of the parking requirements.

Table 2: Compliance with City’s Parking Requirements
Use Bldg. Square
Feet
City Parking
Requirement
Spaces
Required
Retail Uses 65,659 1 stall per 200 sq. ft. 329
Office 214,500 1 stall per 250 sq. ft. 858
Proposed Costco (retail) 161,295 1 stall per 200 sq. ft. 807 Total Parking Required 1,994 spaces
Total Parking Existing 2,512 spaces
Total Parking Spaces Removed 444 spaces
Total Parking Provided*
(*After removal of 444 parking spaces) 2,068 spaces
Based on the data shown in Table 2, an excess of 74 parking spaces will be provided. Accordingly, the project demonstrates compliance with the City’s parking requirements.

Signage:

All signage in Phase 4 of the Foothill Ranch Towne Centre is regulated by a Planned Sign Program (PSP). Said PSP is administered by the Foothill Business Association (“Association”) and establishes differing criteria for tenants occupying various building types and sizes, up to a “Major Tenant” occupying 25,000 to 120,000 sq. ft. Given that Costco is proposed to occupy 165,068 sq. ft., it is Item: 11
573
ATTACHMENT 5 - PC REPORT
PC Agenda Report – February 5, 2026
SDP 05-25-5800, UP 05-25-5801, UP 05-25-5802, UP 05-25-5803, PSP 05-25- 5804, PCN 12-25-5850 (Costco Wholesale)
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necessary to amend the PSP to accommodate a tenant of this size within the Phase 4 sign regulations.

The Association has prepared minor amendments to the PSP, which are summarized in Table 3.

Table 3: Proposed PSP Amendments
Existing PSP Regulation Proposed PSP Regulation
A major tenant is defined as any tenant
occupying 25,000 sq. ft. to 120,000 sq.
ft.

A major tenant would include any
tenant occupying a gross floor area of
25,000 sq. ft. or larger
Sign area limited to ten percent, up to
a maximum of 350 sq. ft. per elevation
Sign area limited to fifteen percent, up
to a maximum of 350 sq. ft. per
elevation
The maximum number of wall mounted
signs shall not exceed three (3)
The maximum number of wall signs
shall not exceed four (4)
Up to two (2) minor secondary wall
signs may be allowed
Up to three (3) minor secondary wall
signs may be allowed, limited to a
single line
The proposed amendments would allow for a large user like Costco to design signage that is appropriate for the scale of the building and surrounding retail uses, while not detracting from the overall building appearance.

Alcohol Sales and Public Convenience or Necessity:

In 2015, the City Council adopted a policy governing the review of off-site retail alcohol sales and Public Convenience or Necessity (PCN) determinations. The Policy establishes procedures for reviewing requests for off-site retail alcohol sales, requires Planning Commission consideration of PCN determinations, and reiterates the Lake Forest Municipal Code requirement for a Use Permit. The Policy also sets special findings, approval criteria, and enhanced public noticing requirements to ensure protection of public safety and welfare, as codified in LFMC Sections 9.72.090(A) and 9.146.130.

The California Department of Alcoholic Beverage Control (ABC) regulates alcohol licensing and generally prohibits new off-sale licenses in high-crime areas or where an undue concentration of licenses exists. Undue concentration occurs when crime rates exceed jurisdictional averages or when license-to-population ratios exceed county standards. ABC may approve a license in such cases if the City determines that public convenience or necessity would be served. While ABC retains final Item: 11
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ATTACHMENT 5 - PC REPORT
PC Agenda Report – February 5, 2026
SDP 05-25-5800, UP 05-25-5801, UP 05-25-5802, UP 05-25-5803, PSP 05-25- 5804, PCN 12-25-5850 (Costco Wholesale)
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authority over license issuance, it considers the City’s PCN determination as part of its review.

The applicant has submitted with ABC for a Type 21 license. The display of alcoholic beverages for purchase are proposed to occupy three aisles totaling approximately 1,765 sq. ft. of the overall 160,942 sq. ft. sales area (1.10%). A PCN is required due to an overconcentration of alcohol licenses within Census Tract 0524.22. At present, there are 13 Type 20 and 21 off-sale licenses within the Census Tract. Based on the ABC Census Tract Authorization, ABC determined that more than six off-sale licenses would be considered an undue concentration and thus subject to the PCN determination requirement.

Alcohol sales would occur during regular business hours, Monday through Friday from 10:00 a.m. to 8:30 p.m., Saturdays from 9:30 a.m. to 7:00 p.m., and Sunday from 10:00 a.m. to 6:00 p.m. (open at 9:00 a.m. for Executive members). No alcoholic beverages would be served or consumed on-site.

Figure 5: Proposed Alcohol Sales Area (in red)
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ATTACHMENT 5 - PC REPORT
PC Agenda Report – February 5, 2026
SDP 05-25-5800, UP 05-25-5801, UP 05-25-5802, UP 05-25-5803, PSP 05-25- 5804, PCN 12-25-5850 (Costco Wholesale)
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Pursuant to the City's Policy, the Chief of Police Services is charged with reviewing the proposed project and preparing a report for Planning Commission consideration. Accordingly, a report was prepared by Police Services and is provided as PC Attachment 8. The report of the Chief of Police Services concluded that issuance of the requested ABC license would not trigger a need for increased law enforcement services or contribute to a current law enforcement problem in the area. Police Services did not recommend any specific conditions of approval for this business.

In addition to the report of the Chief of Police Services, the City's policy also requires a report from the Director of Community Development which is provided as PC Attachment 8.

Along with the standard Use Permit findings in LFMC Section 9.184.040(E), the Policy and LFMC Section 9.164.130 require that the Planning Commission make findings specific to the sale of alcohol for off-site consumption when approving a Use Permit for off-sale alcohol. The additional required findings are identified and discussed below:

1. The sale of alcohol for off-site consumption, as part of the operation of the business, will not result in nuisance activities within the premises or in proximity to the premises.

2. The sale of alcohol for off-site consumption, as part of the operation of the business, will not create a need to change any operational requirements or staffing of law enforcement personnel.

3. The physical design and layout of the business floor plan and associated parking area will not create loitering, noise, traffic or other conditions or situations that may be detrimental or incompatible with other businesses in the adjacent area or permitted uses in the vicinity.

4. The proposed management standards, training and site supervision of the business will deter loitering, noise, traffic, or other conditions for situations that may be detrimental or incompatible with other businesses in the adjacent area or permitted uses in the vicinity
As indicated in the Polices Services report, the proposed alcohol sales use is not expected to result in nuisance activities or other conditions that may be detrimental or incompatible with the surrounding area. The Chief of Police Services has advised that the use will not generate a need to augment or alter police services.

Moreover, the sale of alcohol would represent approximately 1.10% of the floor Item: 11
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ATTACHMENT 5 - PC REPORT
PC Agenda Report – February 5, 2026
SDP 05-25-5800, UP 05-25-5801, UP 05-25-5802, UP 05-25-5803, PSP 05-25- 5804, PCN 12-25-5850 (Costco Wholesale)
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area of the store and be ancillary to the business offerings, which include groceries, household items, clothing, hot and cold prepared foods, pharmacy and medical offerings, and automotive needs. Therefore, the sale of alcohol is not expected to generate a change in operational conditions that is significant to affect loitering, noise, or traffic, nor is it anticipated to create situations that may be detrimental or incompatible with other businesses in the adjacent area.

To approve a PCN, the City’s Policy requires that an additional finding be made by the Planning Commission. The Planning Commission must evaluate and find in the affirmative at least one of the following factors to demonstrate that public convenience or necessity would be served by the issuance of an additional ABC license in the census tract:

1. The sale of alcohol at an additional location within the census tract will allow the consumer to purchase alcohol in conjunction with other specialty goods or services desired by the consumer at the business location.

2. The business will offer a unique product in terms of price, quality, variety, or hours which are not readily available in the local area.

3. The business has the ability to serve an unserved or under-served population.

4. If proposed in conjunction with another primary use, the sale of alcohol will be ancillary to the primary business operations.

Based on staff’s review of the project, the proposed sale of alcohol at the proposed Costco store satisfies factors 1, 2 and 4. Costco is a membership only retail business that offers a variety of products in bulk quantities in a consolidated shopping environment for its members. As previously mentioned, the proposed alcohol sales area would constitute approximately 1.10% of the floor area (1,765 sq. ft.) of the overall 160,942 sq. ft. sales area, which would be ancillary to the various other groceries, goods, and services Costco would offer at the location.

A list of recommended conditions of approval for Planning Commission consideration are listed in PC Attachment 2. The list was derived from the list of potential conditions of approval included in the Council’s PCN Policy. The Policy provides for any or all the conditions listed to be imposed on a case-by-case basis, at the Planning Commission’s discretion. The recommended conditions of approval are consistent with the conditions placed on retail establishments with recent Use Permits.

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ATTACHMENT 5 - PC REPORT
PC Agenda Report – February 5, 2026
SDP 05-25-5800, UP 05-25-5801, UP 05-25-5802, UP 05-25-5803, PSP 05-25- 5804, PCN 12-25-5850 (Costco Wholesale)
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Compliance with Citywide Design Guidelines:

The Citywide Design Guidelines include recommended development standards “to ensure that proposed development is constructed in an aesthetically-pleasing and high-quality manner that is within the character of the community.” The subject property further falls within the 241/Foothill Ranch Commercial Corridor district specific guidelines of the Citywide Design Guidelines. Some of the identifying features of this district are the visibility from the SR-241 corridor as a regional commercial area with large-scale, automobile-oriented destination shopping centers with palm trees as a consistent identifying feature. Table 4 outlines how the project demonstrates compliance with the associated guideline.

Table 4: Design Guidelines
Design Guideline Project Feature
Buildings should contain low,
medium and high elevation massing
elements. Vertical and horizontal
offsets should be provided to
minimize building bulk
Overall, the building design includes a
concrete masonry unit (CMU) block
wainscot, various types and colors of
metal paneling for the primary body, a red
band wrapping the building approximately
¾ of the way up, with coping and cornices
capping off the top. Perforated metal
paneling affixed the exterior walls provide
elements of horizontal offset and vertical
articulation is provided at varying intervals.

Building color and materials may
also be used to emphasize
elevation massing elements
The building includes earth tones with
various hues of tans and gray. The primary
body is constructed of flat metal panels
painted “Surrey Beige,” with the vertical
articulation elements being ribbed metal
paneling painted “Metallic Champagne.”
Vehicular entries to commercial
development should be enhanced
with ornamental landscaping,
decorative paving, raised medians,
gateway structures and/or
monument signage
Access to the project site is primarily
provided via existing signalized
intersections at Market Place/Towne
Centre Drive and Entertainment/Towne
Centre Drive. These shared driveways are
accented with landscape planting strips
and palm trees. This project proposes
maintaining these features and continuing
the ornamental landscape into the project
area.

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ATTACHMENT 5 - PC REPORT
PC Agenda Report – February 5, 2026
SDP 05-25-5800, UP 05-25-5801, UP 05-25-5802, UP 05-25-5803, PSP 05-25- 5804, PCN 12-25-5850 (Costco Wholesale)
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Clearly defined pedestrian paths
should be provided from parking
areas to primary building entrances
and sidewalks along the site’s
perimeter
Two primary pedestrian paths are
provided to the parking areas to the north
and east parking areas. These pedestrian
paths further provide connection to the
surrounding businesses and streets. All
pedestrian paths have a minimum width of
6 ft.
241/Foothill Ranch District Specific Design Guidelines
Design Guideline Project Feature
Ensure that efforts to accommodate
freeway-oriented signage and
elevations do not detract from the
overall building appearance.

Areas of signage are accentuated through
the use of vertical articulation and
perforated metal paneling. These accents
are also carried throughout the building
exterior to maintain a consistent
appearance and not detract from the
overall appearance.

Use consistent architecture on all
sides, given high visibility of the
corridor
The building maintains consistent usage
of CMU block and vertical metal paneling.

Varying heights are incorporated and
areas of pedestrian access are
accentuated through the use of canopies.

Incorporate landscaping that
softens the appearance of buildings
along the freeway
A minimum 15’ landscape planter is
proposed to border the edge of the
property between SR-241 containing a
mixture of bushes and trees.

In designing fencing along the
freeway, incorporate colors and
materials compatible with the
building architecture, to the fullest
extent possible
No new fencing is proposed along the
freeway. All existing fencing is to remain
as is.

Furthermore, the project has been reviewed and approved by the Architectural Review Committee for the Foothill Business Association.

Compatibility with Surrounding Uses:

The proposed project is located in an already developed regional shopping center containing various shops, restaurants, and offices. Also located within the Foothill Ranch Towne Centre are big-box retailers like Walmart and Target, occupying approximately 174,000 sq. ft., and 132,000 sq. ft. respectively. The proposed Costco would be an anchor use of similar size to the existing Walmart and Target Item: 11
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ATTACHMENT 5 - PC REPORT
PC Agenda Report – February 5, 2026
SDP 05-25-5800, UP 05-25-5801, UP 05-25-5802, UP 05-25-5803, PSP 05-25- 5804, PCN 12-25-5850 (Costco Wholesale)
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located on an already developed parcel and would be a retail use on a property that is presently developed with and historically utilized as a retail use. The building design has incorporated elements of the Design Guidelines to ensure a compatible design with the surrounding uses.

Site access with be provided via existing driveways along Towne Centre Drive and the project will utilize the existing circulation patterns connecting with the rest of the Foothill Ranch Towne Centre. Truck deliveries will occur at the rear of the building away from significant customer traffic, similar to the surrounding retail users, before exiting the site along a defined path, minimizing conflicts with the surrounding businesses. Ample open parking will be maintained with an excess of parking stalls available for all users within Phase 4 of the Foothill Ranch Towne Centre.

In 2022, the City Council adopted new mixed-use zoning districts, of which all properties in the Foothill Ranch Towne Centre were zoned as either Mixed Use 32 or Mixed Use 43. Future projects within the Foothill Ranch Towne Centre that propose residential development would be required to prepare additional planning studies to ensure compatibility with the existing and future uses.

ENVIRONMENTAL REVIEW:

The proposed project is exempt from the provisions of the California Environmental Quality Act (CEQA) pursuant to Article 12 – Special Situations, Sec. 15183, Projects Consistent with a Community Plan, General Plan, or Zoning, which mandates that projects which are consistent with the development density established by existing zoning, community plan, or general plan policies for which an EIR was certified shall not require additional environmental review, except as might be necessary to examine whether there are project-specific significant effects which are peculiar to the project or its site.

The City hired an environmental consultant, De Novo Planning Group, to peer review the technical documents related to this project and prepare an Environmental Compliance Checklist analyzing the project and its consistency with the City of Lake Forest 2040 General Plan and accompanying General Plan Final Environmental Impact Report (FEIR) which was certified by the City on June 2, 2020. The Environmental Checklist (PC Attachment 5) concluded that the proposed project is within the scope of the 2040 General Plan FEIR, and no further CEQA documentation is required.

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ATTACHMENT 5 - PC REPORT
PC Agenda Report – February 5, 2026
SDP 05-25-5800, UP 05-25-5801, UP 05-25-5802, UP 05-25-5803, PSP 05-25- 5804, PCN 12-25-5850 (Costco Wholesale)
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PUBLIC NOTICING:

In accordance with the requirements of Section 9.184.040(C)(2) of the Municipal Code of the City of Lake Forest, this project has been noticed in a newspaper of general circulation on January 22, 2026. In addition, on January 20, 2026, public notices were posted at City Hall, sent to all current occupants in Phase 4, and sent to owners of all property within 300 feet of the project boundary.

ATTACHMENTS:

1. Draft Resolution Approving SDP 05-25-5800 and UP 05-25-5803 (MU Exceptions)

2. Draft Resolution Approving UP 05-25-5801 and PCN 12-25-5850 (Alcohol Sales)

3. Draft Resolution Approving UP 05-25-5802 (Light Automotive Repair)

4. Draft Resolution Approving PSP 05-25-5804 (Planned Sign Program Amendments)

5. CEQA 15183 Environmental Checklist

6. Plan Drawings

7. Planned Sign Program Amendments

8. Report of the Chief of Police Services and Report of Director of Community Development for Alcoholic Beverage Sales
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PC ATTACHMENT 1
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PC ATTACHMENT 2
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PC ATTACHMENT 3
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PC ATTACHMENT 4
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PC Attachment 5
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ENVIRONMENTAL COMPLIANCE CHECKLIST
JANUARY 2026
Prepared for:

City of Lake Forest
Community Development Department
100 Civic Center Drive
Lake Forest, CA 92630
Prepared by:

De Novo Planning Group
180 E. Main Street, Suite 108
Tustin, CA 92780
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COSTCO WHOLESALE PROJECT
SITE DEVELOPMENT PERMIT 05-25-5800,
USE PERMIT 05-25-5801, USE PERMIT
05-25-5802, USE PERMIT 05-25-5803, PLANNED
SIGN PROGRAM 05-25-5804, PUBLIC
CONVENIENCE OR NECESSITY 12-25-5850
CEQA Guidelines 15183 Report |
Environmental Compliance Checklist
LEAD AGENCY: CITY OF LAKE FOREST
Community Development Department
100 Civic Center Drive
Lake Forest, CA 92630
Contact: Connor Musler, AICP, Associate Planner
[email protected]
(949) 461-3491
PREPARED BY: DE NOVO PLANNING GROUP
180 E. Main Street, Suite 108
Tustin, California 92780
Contact: Starla Barker, AICP
[email protected]
(949) 396-8193
January 2026
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CEQA Guidelines 15183 | Environmental Compliance Checklist Final | January 2026 i
Table of Contents

1.0 INTRODUCTION AND OVERVIEW......................................................................................................1

2.0 PROJECT DESCRIPTION......................................................................................................................3

2.1 Project Location ............................................................................................................................3

2.2 Existing Setting..............................................................................................................................3

2.3 Project Characteristics..................................................................................................................7

2.4 Project Objectives.........................................................................................................................8

2.5 Discretionary Approvals................................................................................................................9

3.0 CEQA GUIDELINES SECTION 15183 .................................................................................................15

4.0 ENVIRONMENTAL APPROACH AND ANALYSIS................................................................................17 I. Aesthetics....................................................................................................................................19 II. Agriculture and Forestry Resources............................................................................................25 III. Air Quality ...................................................................................................................................29 IV. Biological Resources....................................................................................................................41 V. Cultural Resources......................................................................................................................45 VI. Energy .........................................................................................................................................49 VII. Geology and Soils........................................................................................................................61 VIII. Greenhouse Gas Emissions.........................................................................................................69 IX. Hazards and Hazardous Materials ..............................................................................................85 X. Hydrology and Water Quality .....................................................................................................91 XI. Land Use and Planning..............................................................................................................101 XII. Mineral Resources ....................................................................................................................113 XIII. Noise .........................................................................................................................................115 XIV. Population and Housing............................................................................................................139 XV. Public Services...........................................................................................................................141 XVI. Recreation.................................................................................................................................145 XVII. Transportation ..........................................................................................................................147 XVIII. Tribal Cultural Resources..........................................................................................................153 XIX. Utilities and Service Systems ....................................................................................................156 XX. Wildfire......................................................................................................................................161 REFERENCES..............................................................................................................................................165 REPORT PREPARATION PERSONNEL .........................................................................................................167 Item: 11
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Appendices
Appendix A – Air Quality Report
Appendix B – Cultural Resources Report
Appendix C – Energy Report
Appendix D – Geotechnical Study
Appendix E – GHG Report
Appendix F – Hydrology Report
Appendix G – WQMP
Appendix H – Noise Impact Study
Appendix I – TIS Technical Memo
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List of Figures
Figure 1 Regional Vicinity.................................................................................................................. 5 Figure 2 Project Location .................................................................................................................. 6 Figure 3 Proposed Site Plan ............................................................................................................ 11 Figure 4 Proposed Exterior Elevations............................................................................................ 12 Figure 5 Proposed Landscape Plan ................................................................................................. 13 List of Tables
Table 4-1 South Coast Air Quality Management District Emissions Thresholds .............................. 31 Table 4-2 Construction-Related Maximum Daily Criteria Air Pollutant Emissions (Maximum Pounds Per Day) ............................................................................................. 34 Table 4-3 Operational-Related Maximum Daily Criteria Air Pollutant Emissions (Maximum Pounds Per Day) ............................................................................................. 35 Table 4-4 Comparison of On-site Project Emissions to SCAQMD LSTs............................................. 36 Table 4-5 On-Road Mobile Fuel Generated by Project Construction Activities – By Phase............. 52 Table 4-6 Project Operational Natural Gas and Electricity Usage .................................................... 53 Table 4-7 Energy Resource Summary for Project Construction ....................................................... 54 Table 4-8 Energy Resource Summary for Project Operation............................................................ 54 Table 4-9 Project Consistency with the Lake Forest 2040 General Plan Energy Efficiency Strategies.............................................................................................. 56 Table 4-10 Project Consistency with Applicable State Renewable Energy and Energy Efficiency Strategies....................................................................................... 57 Table 4-11 Annual Average GHG Emissions........................................................................................ 74 Table 4-12 Project Consistency with the CARB’s 2022 Scoping Plan.................................................. 77 Table 4-13 Project Consistency with SCAG’s Connect SoCal (2024-2050 RTP/SCS) ........................... 79 Table 4-14 Project Consistency with the Lake Forest 2040 General Plan ........................................ 104 Table 4-15 Land Use Compatibility for Community Noise Environment.......................................... 117 Table 4-16 Performance Standards for Stationary Noise Sources, Including Affected Projects............................................................................................. 118 Item: 11
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Table 4-17 Existing Ambient Noise Levels ........................................................................................ 123 Table 4-18 Typical Construction Equipment Noise Levels................................................................ 127 Table 4-19 On-Site Construction Noise Impacts............................................................................... 128 Table 4-20 On-Site Construction Noise Impacts – Overlapping Construction.................................. 128 Table 4-21 Mechanical Noise Levels................................................................................................. 129 Table 4-22 Loading Dock Operation Noise Levels............................................................................. 130 Table 4-23 Warehouse Delivery Truck Noise Levels......................................................................... 131 Table 4-24 Trash Compactors Operation Noise Levels..................................................................... 131 Table 4-25 Parking Lot Operation Noise Levels................................................................................ 132 Table 4-26 Parking Lot Cleaning Noise Levels................................................................................... 133 Table 4-27 Tire Installation Center Noise Levels .............................................................................. 133 Table 4-28 Composite On-Site Operational Noise Impacts.............................................................. 134 Table 4-29 Construction Vibration Impacts – Building Damage....................................................... 136 Table 4-30 Construction Vibration Impacts – Human Annoyance ................................................... 137 Table 4-31 Change in Regional Total VMT........................................................................................ 149 Item: 11
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1.0 INTRODUCTION AND OVERVIEW
The City of Lake Forest is the Lead Agency under the California Environmental Quality Act (CEQA).

California Public Resources Code Section 21083.3 and CEQA Guidelines Section 15183 provide that additional environmental review shall not be required for projects that are consistent with the development density established by existing zoning, community plan or general plan policies for which an Environmental Impact Report (EIR) was certified, except as might be necessary to examine whether there are project-specific significant effects which are peculiar to the project or its site. Section 15183 specifies that examination of environmental effects shall be limited to those effects that: (1) Are peculiar to the project or the parcel on which the project would be located; (2) Were not analyzed as significant effects in a prior EIR on the zoning action, general plan, or community plan, with which the project is consistent; (3) Are potentially significant off-site impacts and cumulative impacts which were not discussed in the prior EIR prepared for the general plan, community plan or zoning action; or (4) Are previously identified significant effects which, as a result of substantial new information which was not known at the time the EIR was certified, are determined to have a more severe adverse impact than discussed in the prior EIR.

Section 15183(c) further specifies that if an impact is not peculiar to the parcel or to the proposed project, has been addressed as a significant effect in the prior EIR, or can be substantially mitigated by the imposition of uniformly applied development policies or standards, then an additional EIR need not be prepared for that project solely on the basis of that impact.

Lake Forest 2040 General Plan and FEIR
In early 2018, the City of Lake Forest embarked on an effort to update its General Plan, a State-mandated long-term policy document which identifies the community’s vision for the future. The General Plan provides a framework to guide decisions on growth, development, and conservation of open space and resources in a manner consistent with the quality of life desired by residents and business owners.

In June 2020, the City Council adopted the 2040 Lake Forest General Plan (2040 General Plan). The 2040 General Plan Land Use and Design Element designates the general distribution and intensity of residential, commercial, industrial, open space, public/semi-public, and other categories of public and private land uses throughout the City, which includes mixed-use land use designations in five key areas throughout the City. It also identifies high-level community design objectives for the City of Lake Forest, including the relationship between the public and private realm, streetscapes, best site planning practices, and placemaking strategies.

The environmental impacts resulting from implementation of future development consistent with the land use densities and intensities established in the 2040 General Plan have been evaluated in the 2040 Lake Forest General Plan Final Environmental Impact Report (2040 General Plan FEIR) (State Clearinghouse No. 2019090102). The 2040 General Plan FEIR is a program EIR and was prepared in accordance with CEQA and the CEQA Guidelines. The program EIR comprehensively evaluated environmental impacts that would result from 2040 General Plan implementation, including information related to existing site conditions, analyses of the types and magnitude of project-level and cumulative environmental impacts, and feasible mitigation measures that could reduce or avoid environmental impacts.

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CEQA Assessment
An Environmental Checklist has been prepared pursuant to CEQA Guidelines Section 15183 (Projects Consistent with a Community Plan or Zoning) to determine whether there are project-specific significant effects that are peculiar to the Project or the site and if the proposed project meets the conditions for a streamlined environmental review process.

Summary of Findings
The Environmental Checklist provides an analysis of the proposed Costco Wholesale Project (Project) with respect to the Project’s consistency with the 2040 General Plan, the analysis contained in the 2040 General Plan FEIR, and any site-specific environmental impacts or cumulative impacts that may result from Project implementation.

As explained in the following pages, the proposed Project is consistent with the 2040 General Plan, for which an EIR was prepared and certified, and there are no-site specific or cumulative impacts associated with the proposed Project that have not been fully addressed in a previous environmental document, or that cannot be mitigated to a less than significant level through the application of the uniformly applied development policies and/or standards. This evaluation concludes that the proposed Project is within the scope of the 2040 General Plan FEIR, and that no further CEQA documentation is required.

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2.0 PROJECT DESCRIPTION

2.1 Project Location
The Costco Wholesale Project (referred to herein as “Project” or “Proposed Project”) is located in the northern portion of the City of Lake Forest (City) within the County of Orange; refer to Figure 1, Regional Vicinity. The Project site comprises parcel APN 612-093-13 totaling approximately 16.3-acres located at 26602 Towne Centre Drive; refer to Figure 2, Project Location. The Project site is located within the larger Foothill Ranch Towne Centre, an established multi-tenant commercial center located along Towne Centre Drive between Bake Parkway and Alton Parkway. More specifically, the Project site is located within the portion of the Towne Centre generally bounded by Bake Parkway, Towne Centre Drive, Market Place and the Foothill Transportation Corridor (SR-241), referred to as Phase 4.

Regional access to the site is provided via SR-241 to the south/southwest and the Santa Ana Freeway (I5) located to the southwest. Local access to the site is provided from Towne Centre Drive from Bake Parkway and Alton Parkway.

2.2 Existing Setting
On-Site Land Uses
The Project site is a relatively flat, irregular-shaped property located within the southwestern portion of the Foothill Ranch Towne Centre. The site is developed with an existing 87,263-square foot commercial building formerly operated as a movie theater, a 126,878-square foot building pad, and a 582,225-square foot surface parking area. The Project site is accessible from three driveways on Towne Centre Drive and two driveways from Market Place. Landscape planters with ornamental landscaping and sidewalks are located along the existing building pad and along internal driveways providing access to the site.

Landscape planters with ornamental landscaping and trees are also dispersed throughout the parking aisles within the site.

General Plan and Zoning
According to the City of Lake Forest General Plan Land Use Map, the Project site is designated as MixedUse 43 (MU-43), which provides opportunities for mixtures of commercial, office, and residential uses in the same building, on the same parcel of land, or within the same area. The City of Lake Forest Zoning Map identifies the zoning for the Project site as Mixed-Use 43 in the Foothill Ranch Planned Community, which is consistent with the General Plan. This zoning allows for single-use commercial projects and includes retail uses and light automotive repair/service subject to Lake Forest Municipal Code Chapter

9.73, Mixed-Use District, and any applicable permit requirements. The proposed Project (as described below) is consistent with the development intensity established by the Lake Forest General Plan and Zoning Map for which an EIR was certified; refer also to Section 3.0.

Surrounding Uses
Uses surrounding the Project site include:
• East/northeast: East/northeast of the Project site, situated between the adjacent parking lot and Towne Centre Drive, are Islands and Chipotle restaurants, Chuck E. Cheese, and Heavenly Plastic Item: 11
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CEQA Guidelines 15183 | Environmental Compliance Checklist Final | January 2026 4
Surgery medical office building. These properties are zoned Mixed-Use 43 (MU-43). East of these properties is Towne Centre Drive.
• North: Directly north of the Project site is Market Place, a shared driveway providing access to the Foothill Ranch Towne Centre, followed by a Red Robin restaurant, PetSmart, and a former At Home retail store. These properties are zoned MU-43.
• West/southwest: Immediately west/southwest of the Project site is a landscaped slope, followed by the Foothill Transportation Corridor (SR-241). West/southwest of SR-241 are business park uses zoned Urban Activity (UA) in the Baker Ranch Planned Community. • South: South of the Project site is the Food Festival food court followed by a shared driveway.

Further south of the driveway are three office buildings. Areas to the south are zoned MU-43.

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Beach
Irvine
Laguna
Beach
Laguna
Hills
Laguna Niguel
Laguna Woods
Lake Forest
Mission Viejo
Newport Beach
Orange
Placentia
Rancho Santa
Margarita
Riverside
San Clemente
San Juan
Capistrano
Santa Ana
Tustin
Villa
Park
Yorba Linda
261
73 91
1 55
90 241
22 91
55 74
1 57
133
133
71 5
5 5
405
15 Legend
Project Location
County Boundary
Incorporated Area
National Forest
Sources: California State Geoportal; USGS Transportation Dataset; USDA. Map Date: December 17, 2025.

Figure 1. Regional Map

COSTCO WHOLESALE PROJECT
0 2 4
Miles
Project Location
P a c i f i c O c e a n
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Irvine Lake Forest
Serrano Creek
Borrego Canyon Wash
Lake Forest Dr
Rancho Pkwy
Bake Pkwy
Bake Pkwy
Portola Pkwy
Alton Pkwy
Lake Forest St
Rancho Pkwy
Corozal
Rancho Cir
S
a
g
e
Burbank
Agave
Antibes
Cantora
Forster
Fairfield
Sorrel
Ala
mitos
Blanco
Espalier Pl
Tavella Pl
Salinas
Calliope
Poppy
Blazewood
Lantana
CarriageDr
Rue Monet
Anacapa Ct
Bluebell
Cook
R
u
e
De
Fortuna
Clover
Mission Ct
Kendall
Fuchsia
Galeana
Lunette Ave
Bonita Vis
Catalina
E
nfi
a
l
de
Ave
Monarch
Hyacinth
Lark
Aster
Flore
s
Towne Centre Dr
Finch
Bel l Vista
Blanco
Barberry
Swift
Vista Ter
Torino Dr
Heron
Alton Pkwy
Orchard Rd
Caspian
Auto
Center Dr
Wild
R
o
s
e
Towne Centre Dr
Atlantic Ocean Dr
Dimen
s
ion Dr
Juniper
Windrow Dr
Mallorca
Alter
Private St
Mariposa
Cress
Manzanillo
Wright
Paloma
Morning Glory
Bake Pkwy
Market Pl
Legend
Project Location
City Boundary
Sources: Orange County GIS; California State Geoportal; Vivid Advanced Imagery, 4/26/2023. Map Date: December 17, 2025.

Figure 2. Project Location

COSTCO WHOLESALE PROJECT
0 500 1,000
Feet
Project Location
P a c i f i c O c e a n
241
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2.3 Project Characteristics
The Project proposes to demolish the former movie theater building and existing site improvements (e.g., asphalt and concrete pavement, landscape/shrub islands, utility infrastructure) and construct a new 34- foot tall, 165,068 gross -square foot retail warehouse building with a tire service center located within the northwestern portion of the site; refer to Figure 3, Proposed Site Plan. The proposed building would consist of the main building (158,192 square feet), employee locker mezzanine (489 square feet), a fire department room (477 square feet), a main switch board room (589 square feet), and an open canopy (3,773 square feet). The business is anticipated to be open seven days a week, excluding holidays, and have operating hours between the hours of 10:00 AM and 8:30 PM on weekdays, 9:30 AM to 7:00 PM on Saturdays, and 9:30 AM to 6:00 PM on Sundays (note the business is open one hour earlier Sunday through Friday, and half an hour earlier on Saturdays for Executive Member Hours).

Additional site improvements include parking, landscaping, and utility infrastructure, as described below.

Parking and Site Access
A total of 913 automobile parking spaces would be distributed throughout the site, primarily within the northern, eastern, and southern portions of the site. Additional shared parking is provided throughout Phase 4 of the Foothill Ranch Towne Centre. On-site parking would consist of 647 10-foot wide stalls, 195 9-foot wide stalls, 21 accessible stalls (including 4 van stalls), 12 electric vehicle (EV) stalls, 28 carpool stalls, and 14 vanpool stalls. A bike rack providing short-term parking for 48 bikes would be provided along the southern boundary of the proposed warehouse building, near the building’s primary entrance. Bike lockers providing long-term storage for 10 bikes would be located along the southwestern boundary of the proposed warehouse building. Four solar canopies, totaling 29,880 square feet, and associated battery storage would be located within the parking lot, east of the proposed warehouse building. Shopping cart corrals would be distributed throughout the parking area.

Similar to existing conditions, vehicular and pedestrian access to the larger commercial center and Project site would be provided via existing driveways along Towne Centre Drive and Market Place. These driveways connect to common driveways and drive aisles within the interior of the larger Phase 4 area.

As part of the Project, the common driveway (i.e., Market Place) that extends from Towne Centre Drive between the Project site and the PetSmart building would be partially reconstructed. The existing fourway stop intersection located along the northern boundary of the Project site would be removed and a new three-way stop intersection would be constructed to the east. Pedestrian walkways and crosswalks would be reconstructed along the common driveway. The existing driveway east of the former movie theater building would also be removed and reconstructed to the east of the proposed Costco Warehouse building. Four truck loading docks would be located along the southwestern boundary of the proposed warehouse building. Trucks are anticipated to access the loading docks via the Towne Centre Drive/Market Place intersection.1
1 Delivery trucks would approach from Bake Parkway, turn left onto Portola Parkway, and turn left onto Market Place to access the site via the Towne Centre Drive/Market Place intersection.

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Architecture and Landscaping
The proposed building would incorporate a variety of materials including painted concrete masonry unit (CMU) walls, metal paneling, metal and glass window panels, single- and double-doors, and metal rolling service doors; refer to Figure 4, Proposed Exterior Elevations. Other architectural features include steel trellises, steel columns, perforated metal panels, and branded signage.

Landscaping including groundcover, bushes, and trees would be located around the northern, eastern, and southern perimeters of the building. Interior landscape islands would be added to the parking areas.

Landscaping would be provided along the western perimeter of the Project site, providing separation from SR-241. Street trees would be preserved or replaced as required by the City’s landscape standards; refer to Figure 5, Proposed Landscape Plan.

Infrastructure and Utilities
The Project would connect to existing utilities within the Project area, as described below.

The Project would install domestic water, fire water, and irrigation service lines within the Project site to connect to existing water lines within the site. A proposed sewer lateral would connect to the existing sanitary sewer line within the site. Grease interceptors would be installed along the southern, eastern, and western boundaries of the warehouse building.

The Project would install inlets to capture and convey stormwater into a biofiltration best management practice (BMP) and convey treated flows into a proposed underground detention system, where it would ultimately discharge into the existing onsite storm drain system.

The proposed Project would connect to existing electrical, natural gas, and telecommunications infrastructure.

Project Construction and Phasing
Project construction is anticipated to occur over approximately nine months beginning in October 2026 and ending in June 2027. Construction activities would include demolition, site preparation, grading, building construction, paving, and architectural coating. Construction equipment is anticipated to include concrete/industrial saws, excavators, rubber tired dozers, tractors/loaders/backhoes, graders, scrapers, cranes, forklifts, generator sets, welders, pavers, paving equipment, rollers, and air compressors.

2.4 Project Objectives
The following Project objectives are established for the proposed Project:
• Construct and operate a new Costco warehouse that serves the local community with goods and services from both nationally known businesses and regional and local businesses. • Reduce energy consumption by incorporating sustainable design features and systems with enhanced energy efficiencies meeting State and federal code requirements. • Provide a Costco warehouse in a location that is convenient for its members, the community, and employees to travel to shop and work.
• Provide a state-of-the-art Costco warehouse to better serve the membership in the City of Lake Forest area including members using Costco’s home and/or business delivery service.

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• Enhance the area with a warehouse whose architecture is designed to be responsive to the City of Lake Forest’s Community goals.
• Expand the space available for integrated retail sales of goods and services in the area. • Provide a Costco warehouse in a location that is serviced by adequate infrastructure including roadways and utilities.
• Develop a Costco warehouse that is large enough to accommodate all the uses and services Costco provides to its members elsewhere.

2.5 Discretionary Approvals
The City of Lake Forest, as the Lead Agency, has discretionary authority over the proposed Project. The Project is consistent with the General Plan land use designation and zoning for the site and would require the following discretionary approvals:
• Site Development Permit (SDP 05-25-5800)
• Use Permit (UP 05-25-5801) and Public Convenience or Necessity (PCN 12-25-5850) for alcoholic beverage sale for off-site consumption;
• Use Permit (UP 05-25-5802) for light auto repair in the tire center; • Use Permit (UP 05-25-5803) for exceptions to the mixed-use development regulations; and • Planned Sign Program (PSP 05-25-5804).

The Project would also require administrative approvals from the City for issuance of grading, building, and occupancy permits.

Other agencies, in addition to the City of Lake Forest, may use this document in their decision-making process in the granting of permits/approvals:
• San Diego Regional Water Quality Control Board – National Pollutant Discharge Elimination System (NPDES) Compliance/Low Impact Development (LID) approvals.

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Source: MG2 Corporation, January 16, 2026. Map Date: January 23, 2026.

Figure 3. Proposed Site Plan

FOOTHILL RANCH TOWNE CENTER - COSTCO

LAKE FOREST, CALIFORNIA
0 100 200
Feet
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Source: MG2 Corporation, November 3, 2025. Map Date: December 17, 2025.

Figure 4. Proposed Exterior Elevations

COSTCO WHOLESALE PROJECT
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Source: CCA, Inc., December 4, 2025. Map Date: December 17, 2025.

Figure 5. Proposed Landscape Plan

COSTCO WHOLESALE PROJECT
0 50 100
Feet
Bloodgood London Plane Tree
Fern Pine
Brisbane Box
Date Palm
Mexican Fan Palm
TREES

TREE PALMS
Lemon Drop Fortnight Lily
Texas Japanese Privet
Enchantress Indian Hawthorn
Compact Xylosma
SHRUBS
Halls Honeysuckle

GROUND COVERS
Existing Landscape to Remain

EXISTING LANDSCAPE
Mesa Cobble 2-4"
ES2 Wood Bark Mulch

NON-LIVING GROUND COVER
39 86
26 5
37 837
537
1,477
280
2,119 sf
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3.0 CEQA GUIDELINES SECTION 15183
CEQA Guidelines Section 15183, Projects Consistent with a Community Plan or Zoning, mandates that projects which are consistent with the development density established by existing zoning, community plan, or general plan policies for which an EIR was certified shall not require additional environmental review, except as might be necessary to examine whether there are project-specific significant effects which are peculiar to the project or its site. This streamlines the review of such projects and reduces the need to prepare repetitive environmental studies.

According to the City of Lake Forest General Plan Land Use Map, the Project site is designated as MixedUse 43 (MU-43). The City of Lake Forest Zoning Map identifies the zoning for the Project site as MixedUse 43 in the Foothill Ranch Planned Community. The Project is consistent with the development intensity established by the Lake Forest General Plan and Zoning Map for which an EIR was certified. Specifically, per the Land Use and Design Element of the General Plan and Lake Forest Municipal Code Section

9.73.030(C), the maximum floor area ratio (FAR) for the non-residential portion of a project in the MU-43 land use designation and zoning district is 1.2:1. The Project proposes a FAR of approximately 0.23, and is within the assumed development potential of the MU-43 designation identified in the General Plan Land Use Element Table LU-1 (Land Use Development Potential Summary), and is therefore consistent the development intensity of the General Plan and zoning.

A comprehensive environmental evaluation has been completed for the Project, as documented in the Environmental Checklist. This evaluation concludes that the Project qualifies for streamlined environmental review under CEQA Guidelines Section 15183.

Project-Specific Environmental Review
CEQA Guidelines Section 15183(b) states that:

In approving a project meeting the requirements of this section, a public agency shall limit its examination of environmental effects to those which the agency determines, in an initial study or other analysis:
(1) Are peculiar to the project or the parcel on which the project would be located, (2) Were not analyzed as significant effects in a prior EIR on the zoning action, general plan, or community plan, with which the project is consistent,
(3) Are potentially significant off-site impacts and cumulative impacts which were not discussed in the prior EIR prepared for the general plan, community plan or zoning action, or (4) Are previously identified significant effects which, as a result of substantial new information which was not known at the time the EIR was certified, are determined to have a more severe adverse impact than discussed in the prior EIR.

The attached Environmental Checklist includes a discussion and analysis of any peculiar or site-specific environmental impacts associated with construction and operation of the proposed Project. The Environmental Checklist identifies the applicable City of Lake Forest development standards and policies that would apply to the proposed Project during both the construction and operational phases, and Item: 11
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explains how the application of these uniformly applied standards and policies would ensure that no peculiar or site-specific environmental impacts would occur.

Conclusion
As described above, the proposed Costco Wholesale Project is consistent with the land use designations and development intensities assigned to the Project site by the 2040 General Plan. Cumulative impacts associated with development and buildout of the Project site, as proposed, were fully addressed in the 2040 General Plan FEIR (SCH# 2019090102). Since the proposed Project is consistent with the land use designation and development intensity for the site identified in the 2040 General Plan and analyzed in the 2040 General Plan FEIR, implementation of the proposed Project would not result in any new or altered impacts beyond those addressed in the 2040 General Plan FEIR.

The analysis in the attached CEQA Environmental Checklist demonstrates that there are no site-specific or peculiar impacts associated with the Project and identifies uniformly applied standards and policies that would be applied to the Project.

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4.0 ENVIRONMENTAL APPROACH AND ANALYSIS
This environmental checklist provides an analysis of potential environmental impacts resulting from the proposed Project. Following the format of the City’s Local Guidelines for Implementing the California Environmental Quality Act,
2 environmental effects are evaluated to determine if the project would result in a potentially significant impact triggering additional review under Guidelines Section 15183.

1. Items checked “Significant Project Impact” indicates that the project could result in a significant effect which either requires mitigation for the impact to be reduced to a less than significant level or which has a significant, unmitigated impact.

2. Items checked “Impact not identified by GP EIR” indicates the project would result in a project specific significant impact (peculiar off-site or cumulative) that was not identified in the 2040 General Plan FEIR.

3. Items checked “Substantial New Information” indicates that there is new information which leads to a determination that a project impact is more severe than what had been anticipated by the 2040 General Plan FEIR.

4. Items checked “Consistent with GP EIR” indicates the project meets the following findings, as included in CEQA Guidelines Section 15183:
o The Project is consistent with the development density established by existing zoning or the 2040 General Plan policies for which the 2040 General Plan FEIR was certified. o There are no Project specific effects which are peculiar to the Project or its site, and which the 2040 General Plan FEIR failed to analyze as significant effects. o There are no potentially significant off-site and/or cumulative impacts which the 2040 General Plan FEIR failed to evaluate.
o There is no substantial new information which results in more severe impacts than anticipated by the 2040 General Plan FEIR.

A project does not qualify for a streamlined environmental review under CEQA Guidelines Section 15183 if it is determined that it would result in: 1) a peculiar impact that was not identified as a significant impact under the General Plan EIR; 2) a more severe impact due to new information; or 3) a potentially significant off-site impact or cumulative impact not discussed in the General Plan EIR.

An analysis of each potential environmental effect is provided below the checklist for each subject area. 2 City of Lake Forest, Appendix A: City Of Lake Forest CEQA Significance Thresholds Guide, November 20, 2001 (revised May 6, 2025).

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I. Aesthetics
Would the project:

Significant
Impact
Peculiar to
the Project or
Project Site
Impact
Adequately
Addressed in
the General
Plan EIR
Impact
Substantially
Mitigated by
Uniformly
Applicable
Development
Standards
New
Potentially
Significant
Off-Site or
Cumulative
Impact not
Addressed in
the General
Plan EIR
a. Substantially damage scenic resources,
including scenic vistas from public parks
and views from designated state scenic
highways or arterial roadways?
No Yes No No
b. Create a new source of substantial night
lighting that would result in “sky glow” (i.e.
illumination of the night sky in urban
areas) or “spill light” (i.e. light that falls
outside of the area intended to be lighted)
onto adjacent sensitive land uses?
No Yes No No
c. Create a new source of substantial glare
which would adversely affect daytime
visibility and/or views in the area?
No Yes No No
d. Substantially degrade the existing visual
character or quality of the site and its
surroundings where:
1) The project exceeds the allowed height
or bulk regulations, or exceeds the
prevailing height and bulk of existing
structures?
No Yes No No
2) The project is proposed to have an
architectural style or use the building
materials that will be in vivid contrast to
an adjacent development where that
development has been constructed
adhering to a common architectural
style or theme?
No Yes No No
3) The project is located on a visually
prominent site and, due to its height,
bulk, architecture or signage, will be in
vivid contrast to the surrounding
development or environment
degrading the visual unity of the area?
No Yes No No
4) A project would include unscreened
outdoor uses or materials? No Yes No No
5) A project would result in the
introduction of an architectural feature
or building mass that conflicts with the
No Yes No No
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character of the surrounding
development?
Discussion: The 2040 General Plan FEIR determined that impacts to aesthetic resources would be less than significant through the implementation of policies and actions in the 2040 General Plan. a) Substantially damage scenic resources, including scenic vistas from public parks and views from designated state scenic highways or arterial roadways?
As discussed in the 2040 General Plan FEIR, while Lake Forest contains numerous areas and viewsheds with relatively high scenic value, there are no officially designated scenic vista points in the Lake Forest Planning Area. Additionally, there are no officially designated scenic highways located in the vicinity of Lake Forest. Significant visual resources in the Planning Area include several prominent creeks, including Aliso Creek, Serrano Creek, San Diego Creek, and the Borrego Canyon Wash, and the Eucalyptus groves that surround portions of the lakes. Other prominent visual features throughout the Planning Area include views of ridgelines, hillsides, and canyons.

The nearest public park to the Project site is Borrego Park, located approximately 0.4 miles to the northeast. Mid-to-long range views of the Foothill Ranch Towne Centre, including portions of the Project site, are available from Borrego Park. In addition, long-range views of the Foothill Ranch Towne Centre, including portions of the Project site, are available from the Borrego Canyon Overlook Park, located approximately 1.0 miles to the northeast. There are no officially designated State Scenic Highways that traverse Lake Forest.3 Views from Portola Parkway and Alton Parkway, which are designated as major arterials, and Bake Parkway, a designated primary arterial, are limited due to topography, landscaping features, and existing structures located within the larger Foothill Ranch Towne Centre development. The existing former movie theater building on the Project site can be seen from SR-241, although thisis a State Highway and not a designated arterial.

The Project site is located within the Foothill Ranch Towne Centre, an established multi-tenant commercial center consisting primarily of commercial buildings, parking lots, and landscaping. The Project proposes to demolish a former movie theater building and construct a new retail warehouse building with a tire service center. The Project site itself does not include significant visual resources or prominent visual features, as identified in the 2040 General Plan or 2040 General Plan FEIR. Therefore, redevelopment of the site as proposed would not substantially damage on-site scenic resources. While mid-to-long range views of the Project site are available from Borrego Park and long-range views of the Project site are available from Borrego Canyon Overlook Park, there are no scenic vista points at either of these parks.

Thus, the Project would not substantially damage scenic resources, including scenic vistas from public parks and views from designated scenic highways or arterial roadways. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site 3 California Department of Transportation, California State Scenic Highway System Map, https://caltrans.maps.arcgis.com/apps/webappviewer/index.html?id=465dfd3d807c46cc8e8057116f1aacaa accessed December 15, 2025.

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have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.
b) Create a new source of substantial night lighting that would result in “sky glow” (i.e. illumination of the night sky in urban areas) or “spill light” (i.e. light that falls outside of the area intended to be lighted) onto adjacent sensitive land uses? The Project site and larger Foothill Ranch Towne Centre are developed with commercial uses and currently experience lighting typical of an urbanized area, such as building interior and exterior lighting, parking lot security lighting, landscape lighting, and street lighting along surrounding roadways, including Towne Centre Drive, Alton Parkway, Bake Parkway, and SR-241.

The Project proposes to demolish a former movie theater building and construct a new retail warehouse building with a tire service center. Redevelopment of the site, as proposed, would not involve the introduction of significant new lighting within the Project site or larger Foothill Ranch Towne Centre. The proposed Project would include interior lighting as well as exterior security lighting around the structure, within parking areas, and landscaped areas, similar to existing conditions. The Foothill Ranch Planned Community Development Plan and Supplemental Text requires that all interior and exterior lighting is designed and located to confine direct rays to the premises. 4 Further, Lake Forest Municipal Code Chapter

9.72, Non-Residential Zoning Districts, requires all outdoor lighting be designed and installed so that lighting is confined to the site, and adjacent properties are protected from glare. As part of the City’s review process, the Project’s lighting plan would be reviewed to ensure compliance with Municipal Code Chapter 9.72. Thus, compliance with the City’s established regulatory framework, which would be verified through the City’s plan review process, would ensure potential impacts associated with proposed Project lighting would remain less than significant, consistent with the conclusions in the 2040 General Plan FEIR.

Similar to existing conditions, the proposed building includes potential reflective materials, such as metal paneling and architectural features and glass window panels; however, surface coverage is minimal, and the proposed building is low-rise and would be partially obstructed by vegetation and other commercial buildings in the Foothill Ranch Towne Centre. Further, the proposed building elevation facing SR-241 does not contain glass and would be partially obstructed from drivers along SR-241 by landscaping provided along the western perimeter of the Project site. Therefore, potential glare effects are minimal and would not involve highly reflective materials potentially resulting in significant glare impacts. Access to the Project site would continue to occur from the existing driveways along Towne Centre Drive and Market Place, as well as the common driveways and drive aisles within Phase 4 of the Foothill Ranch Towne Centre shared parking lot, similar to existing conditions. Thus, the Project would not introduce new conditions related to glare from vehicles and trucks exiting the site. Therefore, the Project would not create a new source of substantial glare which would adversely affect daytime visibility and/or views in the area. 4 Foothill Ranch Company, Foothill Ranch Planned Community Development Plan and Supplemental Text, April 1988.

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Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. d) Substantially degrade the existing visual character or quality of the site and its surroundings where:
1) The project exceeds the allowed height or bulk regulations, or exceeds the prevailing height and bulk of existing structures?
2) The project is proposed to have an architectural style or use the building materials that will be in vivid contrast to an adjacent development where that development has been constructed adhering to a common architectural style or theme? 3) The project is located on a visually prominent site and, due to its height, bulk, architecture or signage, will be in vivid contrast to the surrounding development or environment degrading the visual unity of the area?
4) A project would include unscreened outdoor uses or materials? 5) A project would result in the introduction of an architectural feature or building mass that conflicts with the character of the surrounding development? The Project site is within the Foothill Ranch Towne Centre, an established multi-tenant commercial center consisting primarily of commercial buildings, parking lots, and landscaping. The Project proposes to demolish a former movie theater building and construct a new 34-foot tall, 165,068 gross -square foot retail warehouse building with a tire service center located within the northwestern portion of the site.

While the proposed new retail warehouse building and tire service center would occupy a larger building footprint than the exiting former movie theater building, the proposed building is generally consistent in height and scale to the existing commercial building and other buildings within the Foothill Ranch Towne Centre. Further, per the Land Use and Design Element of the General Plan and Lake Forest Municipal Code Section 9.73.030(C), the maximum FAR for the non-residential portion of a project in the MU-43 land use designation and zoning district is 1.2:1. The Project proposes a FAR of approximately 0.23 and is therefore consistent the development intensity of the General Plan and zoning. Thus, the overall building height and bulk of the proposed Project would be consistent with the prevailing height and bulk of other existing structures in the vicinity of the Project site.

The proposed retail warehouse building would incorporate a variety of materials including painted CMU walls, metal paneling, metal and glass window panels, single- and double-doors, and metal rolling service doors. Other architectural features include steel trellises, steel columns, perforated metal panels, and branded signage. The other existing buildings within the Foothill Ranch Towne Centre contain a mix of building materials, colors, and architectural styles, and do not adhere to a common architectural style or theme. Thus, the proposed Project would not have an architectural style or use building materials that would be in vivid contrast to the adjacent buildings.

The Project is not located on a visually prominent site; however, the southwestern portion of the site is visible from SR-241. The proposed Project’s height, bulk, architecture, and signage is generally consistent with the existing commercial buildings within the Foothill Ranch Towne Centre. Thus, the proposed Item: 11
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Project would not be in vivid contrast to the surrounding development or environment degrading the visual unity of the area, nor would the Project result in the introduction of an architectural feature or building mass that would conflict with the character of the surrounding development.

Project operations would occur within the proposed retail building and tire service center. The proposed Project would not include unscreened outdoor uses or materials.

The Project requires approval of a Site Development Permit (Municipal Code Chapter 9.184, Discretionary Permits), which would allow for discretionary review of the Project. The decision-making authority would be required to make findings for approval including consistency with the General Plan, consistency with the Zoning Code, compliance with CEQA, compatibility with surrounding development, and consistency with the Citywide Design Guidelines. Thus, compliance with the City’s established regulatory framework, which would be verified through the City’s development review process, would ensure that the proposed Project would not conflict with applicable development standards, design guidelines, or other regulations governing visual character. Overall, the Project would not degrade the existing visual character of quality of the site and impacts would be less than significant, consistent with the 2040 General Plan FEIR.

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II. Agriculture and Forestry Resources
Would the project:

However, the 2040 General Plan FEIR determined that implementation of the 2040 General Plan would result in the conversion of farmlands, including Prime Farmland and Unique Farmland, to non-agricultural use. As such, impacts would be significant and unavoidable relative to this topic.

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a) Convert Prime Farmland, Unique Farmland, or Farmland of Statewide Importance (Farmland), as shown on the maps prepared pursuant to the Farmland Mapping and Monitoring Program of the California Resources Agency, to non-agricultural use? As discussed in the General Plan FEIR, the City has one zoning district for agricultural uses: A1, Agriculture District. The A1 District is established to provide for agriculture, outdoor recreational uses, and those low intensity uses which have a predominately open space character. It is also intended that this district may be used as an interim zone in those areas which the 2040 General Plan may designate for more intensive urban uses in the future. The majority of the land zoned A1 is currently developed with urban uses or is currently designated for urban uses by both the existing and proposed Land Use Maps. There are some areas in Lake Forest zoned A1 that are not urbanized, but rather, are designated for Regional Park/Open Space uses on the Land Use Map. All of the land within the Planning Area is planned for urban development in one form or another, with the exception of areas designated for Open Space or Regional Park/Open Space uses. The 2040 General Plan FEIR assumed that the land within the City zoned A1 and not designated for Open Space or Regional Park/Open Space uses will eventually be developed with urban land uses, consistent with the 2040 General Plan and Land Use Map. Given the purpose, intent, and flexibility of the established A1 Zoning District, the 2040 General Plan FEIR determined the 2040 General Plan and Land Use Map would not conflict with existing agricultural zoning in the City of Lake Forest.

The Project site is currently developed with a commercial building and paved parking areas and does not contain any Prime Farmland, Unique Farmland, or Farmland of Statewide Importance pursuant to the Farmland Mapping and Monitoring Program.5 Thus, the Project would not involve the conversion of farmland to a non-agricultural use. While the 2040 General Plan FEIR determined that program-level impacts related to implementation of the 2040 General Plan would be significant and unavoidable relative to this criterion, no project-level impacts would occur as a result of Project implementation. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. b) Conflict with existing zoning for agricultural use, or a Williamson Act contract? According to the 2040 General Plan FEIR, there are no lands within the Lake Forest Planning Area that are under a Williamson Act contract. The Project site is currently developed with a commercial building and paved parking areas. The Project site is zoned Mixed-Use 43 and is not zoned for agricultural use, nor is the site under a Williamson Act contract. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. 5 California Department of Conservation, California Important Farmland Finder, https://maps.conservation.ca.gov/DLRP/CIFF/ accessed December 12, 2025.

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c) Conflict with existing zoning for, or cause rezoning of, forest land (as defined in Public Resources Code Section 12220(g)), timberland (as defined by Public Resources Code Section 4526), or timberland zoned Timberland Production (as defined by Government Code Section 51104(g))? d) Result in the loss of forest land or conversion of forest land to non-forest use? According to the 2040 General Plan FEIR, there are no forest lands or timber lands located within the Lake Forest Planning Area. There are also no parcels that are currently zoned as forest land, timber, or timber production.

The Project site is zoned Mixed-Use 43. According to the General Plan, no forest land, timberland, or timberland zoned Timberland Production occur within the City. The Project site is located within an urbanized area and is currently developed. Thus, the proposed Project would not result in the loss of forest land or conversion of forest land to non-forest use. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.
e) Involve other changes in the existing environment, which, due to their location or nature, could result in conversion of Farmland, to non-agricultural use or conversion of forest land to nonforest use? As demonstrated above, the Project site and surrounding area are currently urbanized and are not zoned for or developed with agricultural or forest uses. There are there are no farmlands or forest lands within the Project site or surrounding area. Development of the Project site, as proposed, would be consistent with the General Plan land use and zoning for the site. Therefore, the Project would not involve other changes in the existing environment, which, due to their location or nature, could result in conversion of Farmland, to non-agricultural use or conversion of forest land to non-forest use. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.

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III. Air Quality
Would the project:

No Yes No No
c. Result in a cumulatively considerable net
increase of any criteria pollutant for which
the project region is non-attainment under
an applicable federal or state ambient air
quality standard (including releasing
emissions which exceed qualitative
thresholds for ozone precursors)?
No Yes No No
d. Expose sensitive receptors to substantial
pollutant concentrations? Methodologies
established by SCAQMD for assessing local
impacts, including but not limited to Local
Significance Thresholds and thresholds for
PM2.5 are used for this assessment.

No Yes No No
e. Create objectionable odors affecting a
substantial number of people? No Yes No No
f. Result in a cumulatively considerable net
increase of any criteria pollutants for which
the project region is non-attainment under
an applicable federal or state ambient air
quality standard (including releasing
emissions which exceed quantitative
thresholds for ozone precursors) where
the incremental effect of the project
emissions, considered together with past,
present, and reasonably anticipated further
project emissions, increase the level of any
criteria pollutant above the existing
ambient level?
No Yes No No
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This section is based in part on the Foothill Ranch Costco Project Air Quality Technical Report (Air Quality Report) prepared by Ramboll Americas Engineering Solutions, Inc., dated December 2025, included in its entirety as Appendix A, Air Quality Report.

Discussion: The 2040 General Plan FEIR determined that the 2040 General Plan would not conflict with or obstruct implementation of the applicable air quality plan, nor would it result in odors affecting a substantial number of people. As such, impacts would be less than significant relative to these topics through the implementation of policies and actions in the 2040 General Plan. However, the 2040 General Plan FEIR determined that implementation of the 2040 General Plan has the potential to result in a cumulatively considerable net increase of criteria pollutants for which the project region is nonattainment under an applicable federal or state ambient air quality standard; expose sensitive receptors to substantial pollutant concentrations; and result in localized operational impacts, construction and operational health and toxic air impacts. As such, impacts would be significant and unavoidable relative to these topics.

South Coast Air Quality Management District (SCAQMD) Thresholds The SCAQMD has established significance thresholds to assess the impacts of project-related construction and operational emissions on regional and local ambient air quality. Table 4-1, South Coast Air Quality Management District Emissions Thresholds, shows the mass daily thresholds for construction and operation as adopted by the SCAQMD for criteria air pollutant (CAP) and toxic air contaminant (TAC) emissions. This analysis estimates project-related construction and operational mass emissions and compares the emissions to these mass daily significance thresholds. The analysis also evaluates the localized ambient air quality impacts from on-site construction and operational activities (e.g., emissions from off-road construction equipment, area emissions, energy emissions, mobile emissions, and stationary source emissions) using SCAQMD’s localized significance threshold (LST) methodology. If emission estimates for the proposed Project activities are below the LST emission levels found in the LST mass look-up tables, the proposed construction or operational activity would be considered not significant for air quality.

The SCAQMD has established significance thresholds to assess health risk impacts of TACs from projectrelated emissions sources on nearby sensitive receptors including residents and other human populations.

A substance released into the air is considered toxic if it has the potential to cause adverse health effects in humans, including increasing the risk of cancer upon exposure, or acute and/or chronic noncancer health effects. Examples include certain aromatic and chlorinated hydrocarbons, certain metals, and asbestos. TACs are generated by a number of sources, including stationary sources such as dry cleaners, gas stations, combustion sources, waste processing facilities, and laboratories; mobile sources such as automobiles; and area sources such as landfills.

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Table 4-1
South Coast Air Quality Management District Emissions Thresholds Mass Daily Thresholds (lbs/day)
Pollutant Construction-Related Operational-Related
Nitrogen Oxides (NOx) 100 55
Volatile Organic Compounds (VOC)1 75 55
Coarse Particulates (PM10) 150 150
Fine Particulates (PM2.5) 55 55
Sulfur Oxides (SOx) 150 150
Carbon Monoxide (CO) 550 550
Lead (Pb) 3 3
Toxic Air Contaminants (TACs), Odor, and GHG Thresholds TACs
(including carcinogens and
non-carcinogens)
Maximum Incremental Cancer Risk ≥ 10 in 1 million
Cancer Burden > 0.5 excess cancer cases (in areas ≥ 1 in 1 million) Chronic & Acute Hazard Index ≥ 1.0 (project increment)
Odor Project creates an odor nuisance pursuant to SCAQMD Rule 402 GHG 10,000 MT/yr CO2e for industrial facilities
Ambient Air Quality Standards for Criteria Pollutants
NO2
1-hour average
Annual Arithmetic Mean
SCAQMD is in attainment; project is significant if it causes or contributes to an exceedance of the following attainment standards:

0.18 ppm (state)

0.03 ppm (state) and 0.0534 ppm (federal)
PM10
24-hour Average
Annual Average

10.4 μg/m3(construction); 2.5 μg/m3(operation)

1.0 μg/m3
PM2.5
24-hour Average 10.4 μg/m3
(construction); 2.5 μg/m3(operation)
SO2
1-hour Average
24-hour Average

0.25 ppm (state); 0.075 ppm (federal – 99th percentile)

0.04 ppm (state)
CO
1-hour Average
8-hour Average
SCAQMD is in attainment; project is significant if it causes or contributes to an exceedance of the following attainment standards:
20 ppm (state) and 35 ppm (federal)

9.0 ppm (state/federal)
Source: Ramboll Americas Engineering Solutions, Inc., Foothill Ranch Costco Project Air Quality Technical Report, December 2025.
a) Conflict with or obstruct implementation of the applicable air quality plan? As part of its enforcement responsibilities, the United States Environmental Protection Agency (USEPA) requires that each state with nonattainment areas prepare and submit a State Implementation Plan (SIP) that demonstrates the means to attain the federal standards. The SIP must integrate federal, state, and local plan components and regulations to identify specific measures to reduce pollution in nonattainment areas, using a combination of performance standards and market-based programs. Similarly, under State law, the California Clean Air Act requires an air quality attainment plan to be prepared for areas designated Item: 11
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as nonattainment regarding the federal and State ambient air quality standards. Air quality attainment plans outline emissions limits and control measures to achieve and maintain these standards by the earliest practical date.

The Project site is located within the South Coast Air Basin (SCAB), which is under SCAQMD’s jurisdiction.

The SCAQMD is required, pursuant to the Federal Clean Air Act (FCAA), to reduce emissions of criteria pollutants for which SCAB is in non-attainment. To reduce such emissions, the SCAQMD drafted the 2022 Air Quality Management Plan (AQMP). The 2022 AQMP establishes a program of rules and regulations directed at reducing air pollutant emissions and achieving State and national air quality standards. The 2022 AQMP is a regional and multi-agency effort including the SCAQMD, the California Air Resources Board (CARB), the Southern California Association of Governments (SCAG), and the USEPA. The AQMP’s pollutant control strategies are based on the latest scientific and technical information and planning assumptions, including SCAG’s Regional Transportation Plan/Sustainable Communities Strategy (RTP/SCS), updated emission inventory methodologies for various source categories, and SCAG’s latest growth forecasts. SCAG’s latest growth forecasts were defined in consultation with local governments and with reference to local general plans. The proposed Project is subject to the SCAQMD’s AQMP.

This analysis uses the following indicators to determine consistency with the AQMP:
• Consistency Criterion No. 1: A proposed project would not result in an increase in the frequency or severity of existing air quality violations, or cause or contribute to new violations, or delay the timely attainment of the AQMP’s air quality standards or the interim emissions reductions. • Consistency Criterion No. 2: A proposed project would not exceed the AQMP’s assumptions or increments based on the years of the project build-out phase.

Consistency Criterion No. 1 refers to the California Ambient Air Quality Standards (CAAQS) and National Ambient Air Quality Standards (NAAQS). As shown in Table 4-2 and Table 4-3, the proposed Project construction and operational emissions would be below SCAQMD’s thresholds. As the Project would not generate localized construction or regional construction or operational emissions that would exceed SCAQMD thresholds of significance, the Project would not violate any air quality standards. Thus, no impact is expected, and the Project would be consistent with the first criterion.

Consistency Criterion No. 2 refers to SCAG’s growth forecasts and associated assumptions included in the AQMP. The future air quality levels projected in the AQMP are based on SCAG’s growth projections, which are based, in part, on the general plans of cities located within the SCAG region. Therefore, projects that are consistent with the applicable assumptions used in the development of the AQMP would not jeopardize attainment of the air quality levels identified in the AQMP.

Growth projections included in the 2022 AQMP form the basis for the projections of air pollutant emissions and are based on the General Plan land use designations. The Project proposes to remove a former movie theater building and construct a new retail warehouse building with a tire service center.

The Project would be consistent with the 2040 General Plan land use designation and zoning for the site.

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General Plan. The Project anticipates providing approximately 300 jobs.6 Conservatively assuming the 300 new employees (and their families) relocate to Lake Forest, Project implementation would result in a potential population increase of approximately 834 persons.7 This is a conservative assumption, as it assumes employees would relocate to the City along with their families instead of a scenario of existing Lake Forest residents filling some of the new employment opportunities. It also does not take into the consideration the employees of the recently closed movie theater. The additional increase of 834 persons in the City would increase the City’s existing (2025) population of 87,639 persons8 by less than one percent (approximately 0.95 percent) to 88,473 persons. The 2040 General Plan FEIR estimates a population of 152,462 persons in the City by 2040, constituting an increase of 70,574 people compared to the existing (2019) condition. The Project would be within the population projections anticipated and planned for by the City’s General Plan and would not increase growth beyond the AQMP’s projections. Therefore, the Project would be consistent with the above criteria. Further, the proposed Project’s long-term influence on air quality in the air basin would also be consistent with the SCAQMD and SCAG’s goals and policies and is considered consistent with the 2022 AQMP. The Project would not conflict with or obstruct implementation of the applicable air quality plan. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. b) Violate any air quality standard or contribute substantially to an existing or projected air quality violation? The SCAQMD construction and operational emission thresholds identified in Table 4- 3 of the City of Lake Forest CEQA Significance Thresholds Guide are used for this assessment.

Construction Emissions
Project construction activities would generate short-term emissions of criteria air pollutants.

Construction-generated emissions are short term and temporary, lasting only while construction activities occur, but would be considered a significant air quality impact if the volume of pollutants generated exceeds the SCAQMD’s thresholds of significance.

Construction-related emissions were calculated using the CARB-approved CalEEMod computer program; refer to Appendix A for additional information regarding construction assumptions used in this analysis.

The Project’s predicted maximum daily construction-related emissions are summarized in Table 4-2, Construction-Related Maximum Daily Criteria Air Pollutant Emissions (Maximum Pounds Per Day).

As shown in Table 4-2, all criteria pollutant emissions would remain below their respective thresholds.

While impacts would be considered less than significant, the proposed Project would be subject to compliance with SCAQMD Rules 402, 403, and 1113, which would further reduce specific constructionrelated emissions. As the proposed Project emissions would not worsen ambient air quality, create 6 Kittelson & Associates, Inc., Focused Transportation Impact Study (TIS) Technical Memorandum, November 26, 2025.
7 Based upon an average household size of 2.78 persons per household per the State of California, Department of Finance, E-5 Population and Housing Estimates for Cities, Counties, and the State, 2020-2025, May 2025. 8 State of California, Department of Finance, E-5 Population and Housing Estimates for Cities, Counties, and the State, 2020-2025, May 2025
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additional violations of federal and State standards, or delay SCAB’s goal for meeting attainment standards, impacts associated with Project construction emissions would be less than significant.

Table 4-2
Construction-Related Maximum Daily Criteria Air Pollutant Emissions (Maximum Pounds Per Day) Scenario1
Volatile
Organic
Compounds
(VOC)2
Nitrogen
Oxides
(NOx)
Carbon
Monoxide
(CO)
Sulfur
Oxides
(SOx)2
Coarse
Particulates
(PM10)
Fine
Particulates
(PM2.5)
Unmitigated
Construction (2026) 3.2 31.6 30.3 0.1 10.0 5.1
Unmitigated
Construction (2027) 48.2 40.9 46.1 0.1 3.6 1.9
SCAQMD Threshold 75 100 550 150 150 55
Exceed Threshold? No No No No No No
Source: Ramboll Americas Engineering Solutions, Inc., Foothill Ranch Costco Project Air Quality Technical Report, December 2025.

Notes:

1. Emissions for project construction were estimated using CalEEMod and additional concrete truck idling emissions.

Project construction emissions assume watering control consistent with SCAQMD Rule 403; refer to Appendix A for model outputs.

2. For purposes of this analysis VOC emissions are assumed to be equal to ROG, and SOx emissions are assumed to be equal to SO2.

Operational Emissions
Operational emissions are associated with mobile sources, energy sources, and area sources. Mobile source emissions are generated from vehicle operations associated with Project operations. Energy source emissions include on-site natural gas usage for heating, on-site electricity use, and electricity generated by offsite power plants. Area source emissions are direct sources within four categories:
hearths, consumer products (such as household-type cleaners), architectural coatings, and landscape equipment.

Project operational emissions are shown in Table 4-3, Operational-Related Maximum Daily Criteria Air Pollutant Emissions (Maximum Pounds Per Day). The operations-related criteria air quality impacts have been analyzed using CalEEMod; refer to Appendix A for additional information regarding assumptions used in this analysis.

As shown in Table 4-3, the Project’s operational emissions would not exceed SCAQMD thresholds.

Therefore, impacts would be less than significant. While the 2040 General Plan FEIR determined that implementation of the 2040 General Plan would result in a cumulatively considerable net increase of criteria pollutants for which the project region is non-attainment under an applicable federal or state ambient air quality standard and impacts would be significant and unavoidable, no project-level impacts would occur as a result of Project implementation. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.

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Table 4-3
Operational-Related Maximum Daily Criteria Air Pollutant Emissions (Maximum Pounds Per Day) Emission Category1
Volatile
Organic
Compounds
(VOC)2
Nitrogen
Oxides
(NOx)
Carbon
Monoxide
(CO)
Sulfur
Oxides
(SOx)2
Coarse
Particulates
(PM10)
Fine
Particulates
(PM2.5)
Area 5.2 0.06 7.2 0.0 0.01 0.01
Energy 0.01 0.27 0.22 0.0 0.02 0.02
Mobile3 33.3 11.8 74.4 0.02 -2.4 -0.5
Stationary Sources 0.0 0.02 0.14 0.0 0.0 0.0
SCAQMD Threshold 75 100 550 150 150 55
Exceed Threshold? No No No No No No
Source: Ramboll Americas Engineering Solutions, Inc., Foothill Ranch Costco Project Air Quality Technical Report, December 2025.

Notes:

1. Emissions for project construction were estimated using CalEEMod; refer to Appendix A for model outputs.

2. For purposes of this analysis VOC emissions are assumed to be equal to ROG, and SOx emissions are assumed to be equal to SO2.

3. Negative mobile PM10 and PM2.5 emissions are attributed to the negative VMT for customer and employee vehicles, obtained from the Focused Transportation Impact Study (TIS) Technical Memorandum (TIS Technical Memo) prepared by Kittelson & Associates, Inc.; refer to Appendix I.
c) Result in a cumulatively considerable net increase of any criteria pollutant for which the project region is non-attainment under an applicable federal or state ambient air quality standard (including releasing emissions which exceed qualitative thresholds for ozone precursors)? The proposed Project is located within Orange County, which is currently designated as non-attainment for the federal and State O3 standards, the State PM10 standards, and the federal and State PM2.5 standards. Ozone precursors include VOC and NOX. Construction and operation of cumulative projects would further degrade the local air quality, as well as the air quality of the SCAB. The greatest cumulative impact on regional air quality would be the incremental addition of pollutants mainly from increased traffic from residential, commercial, and industrial development and the use of heavy equipment and trucks associated with the construction of these projects. Air quality would be temporarily degraded during construction activities that occur separately or simultaneously. However, in accordance with the SCAQMD methodology, projects that do not exceed the SCAQMD criteria or can be mitigated to less than criteria levels are not significant and do not add to the overall cumulative impact. Further, adherence to SCAQMD rules and regulations would alleviate potential impacts related to cumulative conditions on a project-by-project basis. As shown in Table 4-2 and Table 4-3, the Project would not result in short-term construction or long-term operational air quality impacts. As a result, the proposed Project would not contribute to a cumulatively considerable net increase of any nonattainment criteria pollutant. Therefore, cumulative impacts associated with implementation of the proposed Project would be less than significant. While the 2040 General Plan FEIR determined that implementation of the 2040 General Plan would result in a cumulatively considerable net increase of criteria pollutants for which the project region is non-attainment under an applicable federal or state ambient air quality standard and impacts would be significant and unavoidable, no project-level impacts would occur as a result of Project implementation.

Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No Item: 11
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impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. d) Expose sensitive receptors to substantial pollutant concentrations? Methodologies established by SCAQMD for assessing local impacts, including but not limited to Local Significance Thresholds and thresholds for PM2.5 are used for this assessment.

Localized Significance Thresholds
The SCAQMD’s LST Methodology was used to evaluate localized ambient air quality impacts from on-site construction (e.g., emissions from on-site off-road construction equipment, material movement, demolition, and construction worker/vendor/haul vehicle travel) and on-site operational activities (e.g., mobile emissions from trucks and passenger vehicles, area emissions, and energy emissions), and whether the proposed Project would expose sensitive receptors to substantial pollutant concentrations. SCAQMD’s LST Methodology is recommended for projects that are less than or equal to five acres. As shown in Table 4-4, Comparison of On-site Project Emissions to SCAQMD LSTs, when assuming a size of five acres, the maximum daily on-site emissions from Project construction and operation are below the SCAQMD LST thresholds. Since the SCAQMD LST thresholds become more stringent with decreasing project area, the use of a five acre LST presents a conservative threshold when used for the Project site, which is approximately 16.3 acres. Therefore, the Project would have a less than significant impact on localized ambient air quality.

Table 4-4
Comparison of On-site Project Emissions to SCAQMD LSTs
Scenario
Maximum Daily On-site Emissions (lbs/day)
Carbon
Monoxide
(CO)
Nitrogen
Oxides (NOx)
1-Hour
Nitrogen
Oxides (NOx)1
Coarse
Particulates
(PM10)
Fine
Particulates
(PM2.5)
Project Construction
Project Construction 40.5 35.2 35.2 8.9 5.1
SCAQMD LSTs2 1,804.0 197.0 109.4 12.0 8.0
SCAQMD LSTs at High
End of Interpolation 1,804.0 197.0 109.4 12.0 8.0
Exceeds SCAQMD LSTs? No No No No No
Project Operation
Project Operation 83.4 8.9 8.9 1.4 0.4
SCAQMD LSTs 1,804.0 197.0 109.4 3.0 2.0
Exceeds SCAQMD LSTs? No No No No No
Source: Ramboll Americas Engineering Solutions, Inc., Foothill Ranch Costco Project Air Quality Technical Report, December 2025.

Notes:

1. An approximated LST was estimated to evaluate the federal 1-hour NO2 standard, as the SCAQMD LST has not been updated to reflect this standard. This value was estimated by scaling the SCAQMD LST that represents the state 1-hr NO2 standard with the ratio of the federal to state 1-hr NO2 standard (0.10 ppm/0.18 ppm).

2. LSTs based on the receptor located at less than 25 meters from a 16.3-acre project site in SRA 19 (Saddleback Valley).

Distance was measured using ArcGIS. LSTs were obtained from the 2008 SCAQMD Final Localized Significance Threshold Methodology, Appendix C, Mass Rate LST Look-up Tables. Available at: http://www.aqmd.gov/home/regulations/ceqa/airquality-analysis-handbook/localized-significance-thresholds. Accessed: September 2025.

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Localized Carbon Monoxide Impacts
There is a potential for the formation of microscale CO “hotspots” in the area immediately around points of congested traffic. Projects contributing to adverse traffic impacts may result in the formation of CO hotspots. Based on the analysis below, the proposed Project would not result in a CO “hot spot”, and a CO “hot spots” analysis is not needed to determine whether the change in the level of service of an intersection in the proposed Project area would have the potential to result in exceedances of the CAAQS or NAAQS or expose sensitive receptors to substantial pollutant concentrations.

The analysis prepared for CO attainment in the SCAB by the SCAQMD can be used to assist in evaluating the potential for CO exceedances in the SCAB. CO attainment was thoroughly analyzed as part of the SCAQMD’s 2003 Air Quality Management Plan (2003 AQMP) and the 1992 Federal Attainment Plan for Carbon Monoxide (1992 CO Plan). As discussed in the 1992 CO Plan, peak CO concentrations in the SCAB are due to unusual meteorological and topographical conditions, and not due to the impact of particular intersections. Considering the region’s unique meteorological conditions and the increasingly stringent CO emissions standards, CO modeling was performed as part of 1992 CO Plan and subsequent plan updates and air quality management plans.

In the 1992 CO Plan, a CO hot spot analysis was conducted for four busy intersections in Los Angeles at the peak morning and afternoon time periods. These analyses did not predict a violation of CO standards.

The busiest intersection evaluated was that at Wilshire Boulevard and Veteran Avenue, which has a daily traffic volume of approximately 100,000 vehicles per day. The 2003 AQMP estimated that the 1-hour concentration for this intersection was 4.6 ppm, which indicates that the most stringent 1-hour CO standard (20.0 ppm) would likely not be exceeded until the daily traffic at the intersection exceeded more than 400,000 vehicles per day.

According to the TIS Technical Memo, which shows existing plus Project peak hour traffic volumes for the main roadway intersections around the proposed Project, the highest peak hourly traffic volumes would be approximately 4,863 vehicles at the intersection of Portola Parkway, El Toro Road, and Santa Margarita Parkway for weekdays and approximately 3,919 vehicles at the same intersection for Saturdays. Further, projected 2028 “with Project peak hour” traffic volumes for the main roadway intersections around the proposed Project would be approximately 5,201 vehicles at the intersection of Portola Parkway, El Toro Road, and Santa Margarita Parkway for weekdays and approximately 4,178 vehicles at the same intersection for Saturdays. Even if these trips happened at every hour of the day, both Project trips and non-Project trips would be below 400,000 vehicles per day at the intersection with the highest daily traffic volumes. Therefore, there is no reason unique to SCAB meteorology to conclude that the CO concentrations at the proposed Project intersections would exceed the 1-hour CO standard. Therefore, the Air Quality Report concludes that the proposed Project would not result in a localized CO “hot spot” and is therefore not expected to have the potential to result in exceedances of the CAAQS/NAAQS or expose sensitive receptors to substantial pollutant concentrations.

Health Risk
The SCAQMD has established significance thresholds to assess health risk impacts of TACs from projectrelated emissions sources on nearby sensitive receptors including residents and other human populations.

A substance released into the air is considered toxic if it has the potential to cause adverse health effects in humans, including increasing the risk of cancer upon exposure, or acute and/or chronic non-cancer health effects. Examples include certain aromatic and chlorinated hydrocarbons, certain metals, and Item: 11
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asbestos. TACs are generated by a number of sources, including stationary sources such as dry cleaners, gas stations, combustion sources, waste processing facilities, and laboratories; mobile sources such as automobiles; and area sources such as landfills.

Construction of the Project is estimated to last approximately nine months, and measurable diesel TAC emissions from the Project would occur for only a brief period during construction activities that would require the on-site use of heavy-duty equipment. The SCAQMD does not require the analysis of health risk from construction-related diesel emissions, due to the short period for which the majority of diesel exhaust emissions would occur.

Based on the nature of the Project construction and operational emissions sources, the Project is not expected to generate TAC emissions that would exceed the health risk significance thresholds.

Conclusion
The Project would not expose sensitive receptors to substantial pollutant concentrations. While the 2040 General Plan FEIR determined that implementation of the 2040 General Plan would expose sensitive receptors to substantial pollutant concentrations, resulting in significant and unavoidable impacts, no project-level impacts would occur as a result of Project implementation. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.
e) Create objectionable odors affecting a substantial number of people? Construction
Odors that could be generated by construction activities are required to follow SCAQMD Rule 402 to prevent odor nuisances on sensitive land uses. SCAQMD Rule 402, Nuisance, states:

A person shall not discharge from any source whatsoever such quantities of air contaminants or other material which cause injury, detriment, nuisance, or annoyance to any considerable number of persons or to the public, or which endanger the comfort, repose, health or safety of any such persons or the public, or which cause, or have a natural tendency to cause, injury or damage to business or property.

During construction, emissions from construction equipment, such as diesel exhaust, and volatile organic compounds from architectural coatings and paving activities may generate odors. However, these odors would be temporary, are not expected to affect a substantial number of people and would disperse rapidly. Therefore, impacts related to odors associated with the Project’s construction-related activities would be less than significant.

Operational
The SCAQMD CEQA Air Quality Handbook identifies certain land uses as sources of odors. These land uses include agriculture (farming and livestock), wastewater treatment plants, food processing plants, chemical plants, composting facilities, refineries, landfills, dairies, and fiberglass molding. The Project would not include any of the land uses that have been identified by the SCAQMD as odor sources. The proposed Project would include various trash receptacles. On-site trash receptacles used by the proposed Item: 11
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project would be properly maintained to prevent adverse odors. With proper housekeeping practices, trash receptacles would be maintained in a manner that promotes odor control, and no adverse odor impacts are anticipated from the uses. Therefore, the proposed Project would not create objectionable odors and operational impacts would be less than significant.

Conclusion
Similar to the conclusions of the 2040 General Plan FEIR, the Project would result in less than significant impacts with respect to odors. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. f) Result in a cumulatively considerable net increase of any criteria pollutants for which the project region is non-attainment under an applicable federal or state ambient air quality standard (including releasing emissions which exceed quantitative thresholds for ozone precursors) where the incremental effect of the project emissions, considered together with past, present, and reasonably anticipated further project emissions, increase the level of any criteria pollutant above the existing ambient level?
As demonstrated above, the proposed Project would not contribute to a cumulatively considerable net increase of any nonattainment criteria pollutant. Therefore, cumulative impacts associated with implementation of the proposed Project would be less than significant. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.

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IV. Biological Resources
Would the project:

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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 Game 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 Game or U.S. Fish and Wildlife Service?
c) Have a substantial adverse effect on state or federally protected wetlands (including, but not limited to, marsh, vernal pool, coastal, etc.) through direct removal, filling, hydrological interruption, or other means?
The Project site is located within the Foothill Ranch Towne Centre and is currently developed with a commercial building and paved parking areas as part of the larger commercial development. Landscape planters with ornamental trees, shrubs, and grass occurs around the building, along internal driveways, and within the parking aisles within the site. Vegetation within the site is not associated with natural vegetation communities. The surrounding area is developed, comprised primarily of commercial uses associated with the Foothill Ranch Towne Centre to the east/northeast, north, and south. Immediately west/southwest of the Project site is a landscaped slope, followed by the Foothill Transportation Corridor (SR-241). The disturbed and maintained condition of the Project site is generally not suitable for any special status species, is devoid of sensitive habitat, and does not contain wetlands or wetland habitat.

The Project site contains some trees, shrubs, and other vegetation that could provide potential nesting habitat for common birds, including birds and raptors protected under the Migratory Bird Treaty Act (MBTA) and California Fish and Game Code (CFG). Construction of the proposed Project could occur during the general bird nesting season (January 15 through September 15) and, therefore, could result in impacts to nesting birds and violation of the MBTA and CFG Code. Direct impacts could occur as a result of the removal of vegetation supporting an active nest. Indirect impacts could occur as a result of construction noise impacting nearby trees if they support an active nest. Given that habitat for nesting birds and raptors is not uncommon within the City, the site does not include any peculiar conditions relative to nesting birds. Project construction activities would be required to comply with the provisions of the MBTA and Sections 3503, 3503.5, 3513 of the CFG, which protect active nests of avian species. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.
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?
The Project site is located within the Foothill Ranch Towne Centre and is currently developed with a commercial building and paved parking areas as part of the larger commercial development. The surrounding area is developed, comprised primarily of commercial uses associated with the Foothill Ranch Towne Centre to the east/northeast, north, and south. Immediately west/southwest of the Project site is a landscaped slope, followed by the Foothill Transportation Corridor (SR-241). The Project site and surrounding area do not serve as a native resident or migratory wildlife corridor or wildlife nursery site, Item: 11
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as the area is completely developed and there are no open space areas or corridors within or adjacent to the Project site. Project construction activities would be required to comply with the provisions of the MBTA and Sections 3503, 3503.5, 3513 of the CFG, which protect active nests of avian species, as previously discussed. Impacts would be less than significant, consistent with the 2040 General Plan FEIR.

Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. e) Conflict with any local policies or ordinances protecting biological resources, such as a tree preservation policy or ordinance?
The Lake Forest Eucalyptus Tree Conservation Ordinance (Lake Forest Municipal Code Chapter 6.20) regulates the transportation and cutting of eucalyptus trees or logs during the period of April 1 through October 31 without a City Permit. The City of Lake Forest does not have any other local policies or ordinances specific to tree preservation, but the General Plan does include policies which support the provision of trees and protection of biological resources throughout the City.

The Project site does not contain any eucalyptus trees that would be removed. Additionally, while the Project would remove existing trees and landscaping to accommodate the proposed improvements, the Project would include new landscaping, including groundcover, bushes, and trees, around the proposed building, within the parking areas, and within the western perimeter of the Project site. Therefore, the Project would not conflict with any local policies or ordinances protecting biological resources and impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.
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? The City of Lake Forest is a participant in the Orange County Central-Coastal Natural Community Conservation Plan/Habitat Conservation Plan (NCCP/HCP). The Project site is currently developed and within an urbanized area and is not located within the boundaries of the NCCP/HCP reserve system.

Therefore, the proposed Project would not conflict with the NCCP/HCP or other approved local, regional, or State habitat conservation plan. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.

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V. Cultural Resources
Would the project:

Discussion: The 2040 General Plan FEIR determined that impacts to cultural resources would be less than significant through the implementation of policies and actions in the 2040 General Plan. a) Cause a substantial adverse change in the significance of a historical resource pursuant to § 15064.5?
According to CEQA Guidelines Section 15064.5, a historical resource is a resource listed in, or determined to be eligible for listing in, the California Register of Historical Resources (CRHR); a resource included in a local register of historical resources; or any object, building, structure, site, area, place, record, or manuscript that a lead agency determines to be historically significant. Generally, a resource shall be considered historically significant if it:
• Is associated with events that have made a significant contribution to the broad patterns of California’s history and cultural heritage;
• Is associated with the lives of persons important in our past; • Embodies the distinctive characteristics of a type, period, region, or method of construction, or represents the work of an important creative individual, or possesses high artistic values; or • Has yielded, or may be likely to yield, information important in prehistory or history.

The Project proposes to demolish the former movie theater building and existing site improvements (e.g., asphalt and concrete pavement, landscape/shrub islands, utility infrastructure) and construct a new retail warehouse building with a tire service center. The existing former movie theater building is part of the larger Foothill Ranch Towne Centre and was constructed in the mid-1990s; thus, the subject building and surrounding structures are less than 50 years old. The Project site and surrounding area does not include any structures that are eligible for listing in the CRHR, listed in a local register of historic resources, or Item: 11
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identified by the City of Lake Forest as historically significant. The Project would not cause a substantial adverse change in the significance of a historical resource pursuant to CEQA Guidelines Section 15064.5.

Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. b) Cause a substantial adverse change in the significance of an archaeological resource pursuant to § 15064.5?
According to CEQA Guidelines Section 15064.5, if an archaeological resource (as defined by Section 21083.2 of the Public Resources Code) is found, the Project site shall be treated in accordance with the provisions of Section 21083.2. If it can be demonstrated that a project will cause damage to a unique archaeological resource, the lead agency may require reasonable efforts to be made to permit any or all of these resources to be preserved in place or left in an undisturbed state.

As part of the Cultural Resources Report, a search of the California Historic Resources Information System (CHRIS) was performed at the South Central Coastal Information Center (SCCIC) that includes the Project site and a one-half mile radius. Results of the records search indicate that 19 previous cultural studies have been conducted within one-half mile of the Project site, seven of which intersected the Project site.

One previously recorded cultural resource was identified within the Project site and 23 cultural resources were identified within a one-half mile radius. The Cultural Resources Report concluded that due to the presence of precontact, isolated surface artifacts within the Project site and precontact sites in the vicinity, there is high sensitivity for precontact resources to occur within the Project area.

It is noted that the Project site is currently developed and has been extensively altered by previous ground disturbance associated with development of the Project site and larger Foothill Ranch Towne Centre. The Project site is underlain by approximately four to 9.5 feet of artificial fill underlain by Capistrano Formation sandstone. Minimal grading, resulting in cuts of less than two feet and fills of less than six feet, are anticipated to occur within the Project site.

Given that the potential for unknown or undiscovered cultural resources to be uncovered through construction activities is not uncommon within the City, the site does not include any peculiar conditions relative to cultural resources. As a standard condition of approval, the Project would be required to comply with 2040 General Plan Action RR-3b, which requires that if construction or grading activities result in the discovery of significant historic or prehistoric archaeological artifacts, all work within 100 feet of the discovery shall cease, the Director of Community Development shall be notified, the resources shall be examined by a qualified archaeologist, paleontologist, or historian for appropriate protection and preservation measures; and work may only resume when appropriate protections are in place and have been approved by the Director of Community Development, reducing potential impacts to less than significant. Additionally, as a condition of approval, archaeological awareness training for Project personnel conducting ground disturbing activities would be conducted by the Project Applicant/Contractor prior to the start of work. Therefore, similar to the conclusion in the 2040 General Plan FEIR, implementation of the 2040 General Plan policies and actions, including Action RR-3b, would ensure the Project would not cause a substantial adverse change in the significance of an archaeological resource pursuant to CEQA Guidelines Section 15064.5 and impacts would be reduced to less than significant. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan Item: 11
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FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. c) Disturb any human remains, including those interred outside of dedicated cemeteries? There are no dedicated cemeteries within the Project site or surrounding area and there is no information to suggest that the site has any undiscovered human remain. The Project site and surrounding area is developed and has been altered by previous ground disturbance associated with past grading activities.

Furthermore, anticipated grading and excavation activities associated with the Project would be minimal.

Due to the extensive ground disturbance that has occurred on the Project site, the potential for the proposed Project to disturb previously undiscovered human remains is highly unlikely.

If human remains are inadvertently discovered, the remains would require proper treatment in accordance with applicable laws, including California Health and Safety Code Section 7050.5, Public Resources Code Section 5097.98, and the California Code of Regulations Section 15064.5(e), which mandate procedures of conduct following the discovery of human remains on non-federal lands.

According to these applicable regulations, should human remains be encountered, all work in the immediate vicinity of the burial would be required to cease, and any necessary steps to ensure the integrity of the immediate area must be taken. The County Coroner would be immediately notified and must then determine whether the remains are Native American in origin. If the Coroner determines the remains are Native American, the Coroner has 24 hours to notify the Native American Heritage Commission (NAHC), who will in turn, notify the person they identify as the Most-Likely-Descendent (MLD) of any human remains. In addition, 2040 General Plan Action RR-3b requires that if human remains are discovered during any ground disturbing activity, work shall stop until the Director of Community Development and the Orange County Coroner have been contacted. If the human remains are determined to be of Native American origin, the NAHC and the MLDs shall be consulted; and work may only resume when appropriate measures have been taken and approved by the Community Development Director.

Therefore, similar to the conclusion in the 2040 General Plan FEIR, compliance with the established regulatory framework (California Health and Safety Code Section 7050.5, Public Resources Code Section 5097.98, and the California Code of Regulations Section 15064.5(e)), including Action RR-3b, which details the appropriate actions required in the event human remains are encountered, will ensure the Project’s potential impacts concerning human remains would be less than significant. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.

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VI. Energy
Would the project:

Discussion: The 2040 General Plan FEIR determined that impacts to energy would be less than significant through the implementation of policies and actions in the 2040 General Plan. This topical area is addressed in the 2040 General Plan FEIR Greenhouse Gases, Climate Change, and Energy section.

REGULATORY FRAMEWORK
Federal and State agencies regulate energy use and consumption through various means and programs.

On the federal level, the United States Department of Transportation (USDOT), the United States Department of Energy, and the USEPA are three federal agencies with substantial influence over energy policies and programs. On the state level, the California Public Utilities Commission (PUC) and the California Energy Commission (CEC) are two agencies with authority over different aspects of energy. Key federal and State energy-related laws and plans are summarized below.

California Green Building Standards (Title 24, Part 11) The California Green Building Standards Code (California Code of Regulations, Title 24, Part 11), commonly referred to as CALGreen, establishes standards to enhance the design and construction of buildings through the use of sustainable construction practices and building concepts that have positive environmental impacts. The California Building Standards Commission developed CALGreen in an effort to meet the State’s landmark initiative Assembly Bill (AB) 32 goals, which established a comprehensive program of cost-effective reductions of greenhouse gas (GHG) emissions to 1990 levels by 2020. CALGreen was developed to (1) reduce GHG emissions from buildings; (2) promote environmentally responsible, cost-effective, and healthier places to live and work; (3) reduce energy and water consumption; and (4) respond to the environmental directives of the administration. CALGreen requires that new buildings employ water efficiency and conservation, increase building system efficiencies (e.g., lighting, Item: 11
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heating/ventilation and air conditioning [HVAC], and plumbing fixtures), divert construction waste from landfills, and incorporate electric vehicles charging infrastructure.

California Building Energy Efficiency Standards (Title 24, Part 6) The California Building Energy Efficiency Standards (California Code of Regulations Title 24, Part 6), also known as the California Energy Code, was first established in 1978 in response to a legislative mandate to reduce California's energy consumption. The Energy Code contains energy and water efficiency requirements (and indoor air quality requirements) for newly constructed buildings, additions to existing buildings, and alterations to existing buildings. The standards are updated periodically to allow consideration and possible incorporation of new energy efficiency technologies and methods.

In general, Title 24 requires the design of building shells and building components to conserve energy, such as through the installation of energy efficient windows, insulation, lighting, ventilation systems, rooftop solar panels, and other features that reduce energy consumption in homes and businesses. The standards are updated periodically to allow consideration and possible incorporation of new energy efficiency technologies and methods. Buildings permitted on or after January 1, 2026, must comply with the 2025 Title 24 Standards. When compared to the 2022 Title 24 standards, the 2025 update focuses on expanding the use of heat pumps for space conditioning and water heating in newly constructed singlefamily, multifamily, and select nonresidential buildings; increasing on-site renewable energy using solar panels and battery storage systems; encouraging electric-readiness; and strengthening ventilation standards.

Senate Bill 100
Senate Bill (SB) 100 (Chapter 312, Statutes of 2018) renewed and accelerated the Renewable Portfolio Standard. It requires that retail sellers and local publicly owned electric utilities procure a minimum quantity of electricity products from eligible renewable energy resources so that the total kilowatt-hours (kWh) of those products sold to their retail end-use customers achieve 44 percent of retail sales by December 31, 2024; 52 percent by December 31, 2027; 60 percent by December 31, 2030; and 100 percent by December 31, 2045. SB 100 requires the California Public Utilities Commission (CPUC), CEC, CARB, and all other State agencies to incorporate the policy into all relevant planning. In addition, SB 100 requires the CPUC, CEC, and CARB to utilize programs authorized under existing statutes to achieve that policy and, as part of a public process, issue a joint report to the Legislature by January 1, 2021, and every four years thereafter, that includes specified information relating to the implementation of SB 100. a) Result in potentially significant environmental impact due to wasteful, inefficient, or unnecessary consumption of energy resources, during project construction or operation? For purposes of this analysis, impacts to energy resources are considered to be significant if the Project would result in the wasteful, inefficient or unnecessary consumption of fuel or energy, and conversely if the Project would not incorporate renewable energy or energy efficiency measures into building design, equipment use, transportation or other Project features. To determine whether a Project would result in the wasteful, inefficient or unnecessary consumption of fuel or energy, and conversely whether the Project would fail to incorporate renewable energy or energy efficiency measures into building design, equipment use, transportation or other Project features, Appendix F of the CEQA Guidelines identifies six categories of potential energy-related environmental impacts:

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1. The Project’s energy requirements and its energy use efficiencies by amount and fuel type for each stage of the Project including construction, operation, maintenance, and/or removal. If appropriate the energy intensiveness of materials may be discussed.

2. The effects of the Project on local and regional energy supplies and on requirements for additional capacity.

3. The effects of the Project on peak and base period demands for electricity and other forms of energy.

4. The degree to which the Project complies with existing energy standards.

5. The effects of the Project on energy resources.

6. The Project’s projected transportation energy use requirements and its overall use of efficient transportation alternatives.

The following discussion provides calculated levels of energy use expected for the proposed Project, based on commonly used modelling software (i.e., CalEEMod v.2022.1 and the California Air Resource Board’s EMFAC2021). It should be noted that many of the assumptions provided by CalEEMod are conservative relative to the Project; thus, this discussion provides a conservative estimate of proposed Project emissions.

Project Construction
Construction of the proposed Project requires the use of transportation fuel, including gasoline, and diesel use in construction equipment, material transport and delivery via vendor/hauling trucks, and construction worker vehicles. Fuel consumed by off-road construction equipment would be the primary energy resource expended over the course of construction, while VMT associated with the transportation of construction materials and construction worker commutes would also result in fuel consumption. Offroad construction equipment associated with construction activities would use diesel fuel. Construction workers would travel to and from the Project site throughout the duration of construction; this analysis assumes that construction workers would primarily use gasoline-powered passenger vehicles.

On-Road Vehicles (Construction)
Project construction would require the use of on-road trucks for soil hauling and deliveries. Table 4-5, OnRoad Mobile Fuel Generated by Project Construction Activities – By Phase, describes gasoline and diesel fuel used by on-road mobile sources during each phase of the construction schedule.

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Table 4-5
On-Road Mobile Fuel Generated by Project Construction Activities – By Phase Construction Phase # of
Days
Total Daily
Worker
Trips(1)
Total Daily
Vendor
Trips(1)
Total
Hauler
Trips(1)
Gallons of
Gasoline
Fuel(2)
Gallons of
Diesel Fuel(2)
Demolition (2026) 48 15.0 0 121.3 491 18,972
Site Preparation (2026) 12 17.5 0 0 143 0
Grading (2026) 16 20.0 0 50.8 218 2,646
Grading (2027) 50 20.0 0 50.8 671 8,162
Building Construction
(2027) 135 52.8 27.1 0 4,782 6,542
Concrete Pour (2027) 102 0 8.2 0 0 1,720
Paving (2027) 18 15.0 0 0 181 0
Architectural Coating
(2027) 38 21.1 0 0 538 0
Total 7,024 38,042
Source: Ramboll Americas Engineering Solutions, Inc., Foothill Ranch Costco Project Energy Technical Report, December 2025.

Notes:

1. Provided by CalEEMod.

2. Refer to Appendix C for further detail.

Off-Road Vehicles (Construction)
Off-road construction vehicles would primarily use diesel fuel during the construction phase of the Project. Off-road construction vehicles expected to be used during the construction phase of the Project include, but are not limited to, excavators, tractors/loaders/backhoes, forklifts, and graders. The Project is estimated to use 45,288 gallons of diesel fuel for off-road construction equipment during the demolition, site preparation, grading, building construction, paving, and architectural coating phases of the Project; refer to Appendix C for detailed calculations.

Project Operation
Electricity and Natural Gas
Energy requirements are evaluated for the first year of the proposed Project operations, which would be 2027. The proposed Project’s energy consumption was estimated using CalEEMod default methodologies for non-mobile sources, including building energy use, which is assumed to include both natural gas and electricity consumption.

The proposed Project would generate energy demand during operation of the proposed building and parking lot. Total annual unmitigated electricity (kWh) and natural gas (kBTU) usage associated with the operation of the Project is shown in Table 4-6, Project Operational Natural Gas and Electricity Usage.

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Table 4-6
Project Operational Natural Gas and Electricity Usage
Energy Resource Project Annual
Consumption
Orange County
Annual
Consumption
Project Construction
Contribution to Orange
County Annual
Consumption
Annual Electricity Demand (kWh/year) 2,097,813 19,225,145,140 0.01% Annual Natural Gas Demand (kBTU/yr) 988,265 56,160,224,134 0.002% Source: Ramboll Americas Engineering Solutions, Inc., Foothill Ranch Costco Project Energy Technical Report, December 2025.

As shown in Table 4-6, Project operational electricity usage is forecast to represent an approximately 0.01 percent increase above the County’s typical annual electricity consumption. Project operational natural gas usage is forecast to represent an approximately 0.002 percent increase above the County’s typical annual natural gas consumption. This increase is minimal in the context of the County as a whole.

On-Road Vehicles (Operation)
The Project would generate vehicle trips during its operational phase, including customer and employee vehicles visiting the proposed warehouse, warehouse and tire center delivery trucks, and Transport Refrigeration Units (TRU) that are mounted on the trailers of a portion of the warehouse delivery trucks.

On-road vehicle fuel consumption for the proposed Project operation is calculated by dividing the VMT by each vehicle type with the respective average fuel efficiency of these vehicle types operating in Orange County in calendar year 2027. TRU fuel consumption is calculated based on the hours of TRU operation and the average fuel consumption rate of TRU trailers operating in Orange County in calendar year 2027.

As discussed in Section XVII, Transportation, the TIS Technical Memo concluded that the Project would result in a net reduction in VMT across the region by shifting a proportion of existing warehouse trips to other existing Costco locations to a new, more convenient (i.e., shorter travel distance) location. The proposed Project would provide an additional option for existing Costco members and would serve members near the Project site more efficiently, resulting in less transportation energy consumption compared to warehouse locations further away. Overall, the proposed Project is expected to result in a net reduction in on-road vehicle fuel consumption due to the net decrease in VMT from customer and employee vehicles visiting the warehouse.

Operational mobile source gasoline consumption due to on-road customer and employee vehicles (gasoline and plug in hybrid vehicles) is estimated to be -58,677 gallons per year. Operational mobile source natural gas consumption due to on-road customer and employee vehicles (natural gas vehicles) is estimated to be -4,092 kBTU per year. Operational mobile source diesel consumption due to on-road customer and employee vehicles (diesel vehicles), delivery trucks, and TRUs is estimated to be 43,636 gallons per year.

Other
The proposed Project will result in gasoline usage from landscape equipment used on-site during Project operation. The estimated annual consumption of gasoline from landscape equipment is 381 gallons.

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The proposed Project includes one compressed natural gas-powered emergency generator, rated at 95 horsepower, to support warehouse operations. The estimated annual consumption of natural gas from the emergency generator is 91,301 kBTU.

Conclusion
Table 4-7, Energy Resource Summary for Project Construction, and Table 4-8, Energy Resource Summary for Project Operation, show the overall energy consumption estimated for Project construction and operation, respectively. These amounts are compared to Orange County annual consumption. As shown, the Project’s contribution to the overall County energy consumption would be minimal. The proposed Project’s projected energy demand is consistent with, and a small percentage of, regional projections and would not require additional electricity generation capacity or petrol or fossil fuel resource extraction.

Further, the Project is not expected to have a substantial impact on peak and base period demands for electricity and other forms of energy. In addition, energy use during construction would be temporary and would cease at the completion of construction activities.

Table 4-7
Energy Resource Summary for Project Construction
Energy Resource
Project Construction
Energy Consumption
(gallons)
Orange County
Annual Consumption
(gallons)
Project Construction
Contribution to
Orange County
Annual Consumption
Gasoline (2026) 853 1,123,161,101 0.0001%
Diesel (2026) 36,523 175,840,601 0.02%
Gasoline (2027) 6,173 1,102,433,345 0.001%
Diesel (2027) 46,807 175,943,536 0.03%
Sources: Ramboll Americas Engineering Solutions, Inc., Foothill Ranch Costco Project Energy Technical Report, December 2025.

Table 4-8
Energy Resource Summary for Project Operation
Energy Resource Project Operation
Energy Consumption
Orange County
Annual
Consumption1,2
Project Operation
Contribution to
Orange County
Annual Consumption
Electricity (kWh/yr) 2,065,126 19,225,145,140 0.01%
Natural Gas (kBTU/yr) 1,075,473 56,160,224,134 0.002%
Gasoline (gallons/yr) -58,296 1,102,433,345 -0.01%
Diesel (gallons/yr) 43,637 175,943,536 0.02%
Sources: Ramboll Americas Engineering Solutions, Inc., Foothill Ranch Costco Project Energy Technical Report, December 2025.

Notes:

1. Diesel and gasoline consumption data for Orange County and the State of California are obtained from EMFAC2021 and OFFROAD2021 for calendar year 2027.

2. Electricity and natural consumption data for Orange County obtained from https://www.energy.ca.gov/ for calendar year 2024 as that was the most recent data available.

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The proposed Project would use energy resources for the operation of the proposed building and landscaping maintenance (e.g., electricity, natural gas, and gasoline), for on-road vehicle trips (e.g., gasoline and diesel fuel) generated by the Project (both during Project construction and operation), and from off-road construction activities associated with the Project (e.g. diesel fuel). Each of these activities would require the use of energy resources. There are no unusual Project characteristics or construction processes that would require the use of equipment that would be more energy intensive than is used for comparable activities, or equipment that would not conform to current emissions standards (and related fuel efficiencies). Similarly, there are no unusual Project characteristics that would require electricity, gasoline, natural gas, and diesel consumption that would be more energy intensive than is used for comparable activities, or equipment that would not conform to current emissions standards (and related fuel efficiencies).

The Project would be responsible for conserving energy, to the extent feasible, and would be required to comply with Statewide and local measures regarding energy conservation, such as Title 24 building efficiency standards. Similar to the conclusions of the General Plan FEIR, the proposed Project would be in compliance with all applicable federal, State, and local regulations regulating energy usage. For example, Southern California Edison (SCE) is responsible for the mix of energy resources used to provide electricity for its customers, and it is in the process of implementing the Statewide Renewable Portfolio Standard (RPS) to increase the proportion of renewable energy (e.g., solar and wind) within its energy portfolio. SCE has achieved at least a 33 percent mix of renewable energy resources and will be required to achieve a renewable mix of at least 50 percent by 2030. Additionally, energy-saving regulations, including the latest State Title 24 building energy efficiency standards (“part 6”), would be applicable to the proposed Project. Other statewide measures, including those intended to improve the energy efficiency of the statewide passenger and heavy-duty truck vehicle fleet (e.g., the Pavley Bill and the Low Carbon Fuel Standard) are improving vehicle fuel economies, thereby conserving gasoline and diesel fuel.

These energy savings would continue to accrue over time.

Over the lifetime of the proposed Project, the fuel efficiency of the vehicles being used for Project operation is expected to improve. The amount of fuel consumption from vehicular trips to and from the Project site during operation would correspondingly decrease over time as vehicles become more efficient. Numerous regulations have been adopted that encourage, and require, increased fuel efficiency.

For example, CARB has adopted an approach to passenger vehicles that combines the control of smogcausing pollutants and GHG emissions into a single coordinated package of standards. The approach also includes efforts to support and accelerate the numbers of plug-in hybrids and zero-emissions vehicles in California. As such, operation of the proposed Project is expected to use decreasing amounts of fuel over time, due to advances in fuel economy.

As a result, the Project would not result in any significant adverse impacts related to Project energy requirements, energy use inefficiencies, and/or the energy intensiveness of materials by amount and fuel type for each stage of the Project including construction, operations, maintenance, and/or removal. The electricity provider to the site, SCE, maintains sufficient capacity to serve the proposed Project. The Project would be required to comply with all existing energy efficiency standards and would not result in significant adverse impacts on energy resources. Therefore, the proposed Project would not result in a wasteful, inefficient, or unnecessary use of energy resources during Project construction or operation.

Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Item: 11
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Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. b) Conflict with or obstruct a state or local plan for renewable energy or energy efficiency? The Project is required to comply with all applicable local and State plans, regulations, and policies for renewable energy or energy efficiency. The Project proposes features consistent with the applicable requirements of the Title 24 Building Energy Efficiency Standards, including the installation of solar panels and accompanying onsite solar PV batteries which will generate onsite renewable energy for the Project.

Furthermore, as discussed above, the proposed Project is expected to result in a net reduction in on-road vehicle fuel consumption due to the net decrease in VMT from customer and employee vehicles visiting the warehouse. Overall, the Project would not conflict with applicable State renewable energy and energy efficiency strategies or the policies and actions related to energy efficiency in the City of Lake Forest General Plan, as demonstrated in Table 4-9, Project Consistency with the Lake Forest 2040 General Plan Energy Efficiency Strategies, and Table 4-10, Project Consistency with Applicable State Renewable Energy and Energy Efficiency Strategies. As such, similar to the conclusions of the 2040 General Plan FEIR, the Project would not conflict with or obstruct a State or local plan for renewable energy or energy efficiency.

Table 4-9
Project Consistency with the Lake Forest 2040 General Plan Energy Efficiency Strategies # Policy/Action Consistency Analysis
PF-6.1 Compliance with State Legislation. Comply
with all state requirements regarding the
generation of power and encourage energy
providers to investigate the use or expansion
of renewable sources of energy.

Consistent. The Project would comply with all state
requirements regarding the generation of power.

The electricity for the operation of the Project would
be supplied by SCE, which is required by the
California Renewables Portfolio Standard program to
meet the retail sales milestones for the power it
delivers to customers. Additionally, the Project
includes solar panels which would generate
renewable electricity and displace some of the
electricity used by the Project.

PF-6.2 New Development. Continue to require new
development and redevelopment to provide
verification from energy utilities that states
they are able to accommodate the additional
demand for service.

Consistent. This is a measure that the City would
implement rather than an individual project.

However, the Project would not conflict with the
City's ability to implement this measure.

Additionally, the additional energy demand of the
Project can be accommodated by local energy
utilities.

PF-6.3 City-Sponsored Projects and Activities.

Evaluate renewable energy capacity on
municipal property and renewable energy use
in City-sponsored projects and activities.

PF-6.4 Business Community. Support the decisions of
the Lake Forest business community as they
select and implement the most appropriate,
financially feasible, and responsible energy
source for their individual operations.

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Table 4-9 (continued)
Project Consistency with the Lake Forest 2040 General Plan Energy Efficiency Strategies # Policy/Action Consistency Analysis
PF-6.5 Conservation. Promote conservation
strategies during design, construction, and
maintenance of facilities.

Consistent. The Project includes a number of
measures to reduce energy usage and incorporates
sustainability features consistent with Title 24 energy requirements, such as energy-efficient lighting,
building materials, and HVAC systems. For a full list
of measures, refer to Section VIII, Greenhouse Gas
Emissions.

PF-6.8 Innovation. Encourage innovative energy
management solutions in new developments.

Consistent. The Project would meet or exceed the
Title 24 energy efficiency standards in effect at the
time of building permit application. The Project
includes a number of measures to reduce energy
usage and incorporates sustainability features
consistent with Title 24 energy requirements, such as
energy-efficient lighting, building materials, and
HVAC systems. Additionally, the Project would
include solar panels which would provide renewable
energy to the Project.

PF-6.9 Promote Energy Conservation in Existing
Building Stock. Promote energy conservation
by residents and businesses in existing
structures, through the City’s newsletter,
flyers, and website, in close coordination with
other agencies and local energy providers,
including the SCAQMD and Southern
California Edison.

PF-6b Continue to review development projects to
ensure that all new public and private
development complies with the California
Code of Regulations, Title 24 standards as well
as the energy efficiency standards established
by the General Plan and the Municipal Code.

Consistent. The Project would meet or exceed the
Title 24 energy efficiency standards in effect at the
time of building permit application. Furthermore, the
proposed Project will comply with the CALGreen
standards in effect at the time of the building permit
application, as applicable.

Source: City of Lake Forest, Lake Forest 2040 General Plan, June 2020.

Table 4-10
Project Consistency with Applicable State Renewable Energy and Energy Efficiency Strategies Plan Category Description Consistency Analysis
California
Renewables
Portfolio
Standard
(RPS) and SB
100
As most recently amended by SB 100
(2018), California’s RPS increases the
proportion of electricity from renewable
sources to 33 percent renewable power
by 2020; 50 percent renewable power by
2026; and 60 percent renewable power
by 2030. SB 350 (2015) also requires the
State Energy Resources Conservation
and Development Commission to double
(by 2030) the energy efficiency savings in
electricity and natural gas final end uses
of retail customers through energy
efficiency and conservation.

Consistent. The Project would comply with all State
requirements regarding the generation of power.

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Table 4-10 (continued)
Project Consistency with Applicable State Renewable Energy and Energy Efficiency Strategies Plan Category Description Consistency Analysis
California
Code of
Regulations,
Title 24, Part
6 Title 24, Part 6 of the California Code of
Regulations establishes energy and
water efficiency requirements for
residential and non-residential new
construction, additions to existing
buildings, and alterations to existing
buildings.

Standards include requirements for
water heating, HVAC, lighting, electrical
systems, and solar design.

Consistent. The Project would meet or exceed the
Title 24 energy efficiency standards in effect at the
time of building permit application. The Project
includes a number of energy and water efficiency
features, such as energy-efficient lighting, building
materials, and HVAC systems and water-efficient
landscaping and plumbing fixtures. For a full list of
measures, refer to Section VIII, Greenhouse Gas
Emissions.

Assembly Bill
1109
The Lighting Efficiency And Toxics
Reduction Act (AB 1109) requires a
reduction in average statewide electrical
energy consumption by not less than 50
percent from the 2007 levels for indoor
residential lighting and not less than 25
percent from the 2007 levels for indoor
commercial and outdoor lighting by
2018.

Consistent. The Project would not conflict with the
implementation of AB 1109. Additionally, the
proposed Project will incorporate several
sustainability and energy efficiency measures
including green building practices as required by the
Title 24 energy efficiency standards in effect at the
time of building permit application.

California
Green
(CALGreen)
Building
Standards
Code
CalGreen establishes green building
standards to meet the goals of AB 32.

CalGreen includes standards for
residential and nonresidential structures
such as new buildings or portions of new
buildings, additions and alterations, and
all occupancies where no other state
agency has the authority to adopt green
building standards applicable to those
occupancies. Standards include
requirements for site development,
indoor and outdoor water use,
construction waste reduction, disposal
and recycling and building maintenance
and operation.

Consistent. The Project would comply with the
CALGreen standards in effect at the time of the
building permit application, as applicable.

AB 1493
(Pavley
Regulations)
Reduces GHG emissions in new
passenger vehicles from model years
2012-2016 (Phase I) and model years
2017–2025 (Phase II). Also reduces
gasoline consumption to a rate of 31
percent of 1990 gasoline consumption
(and associated GHG emissions) by 2020.

Consistent. Although this goal is not the
responsibility of an individual development project,
the Project would not conflict with the
implementation of the AB 1493 regulations. Further,
as shown in Table 4-8, Energy Resource Summary for
Project Operation, the Project would reduce
operational regional gasoline consumption.

Low Carbon
Fuel Standard
(LCFS)
Establishes protocols for measuring and
reducing the life-cycle carbon intensity
of transportation fuels and helps to
establish use of alternative fuels.

Consistent. Although this goal is not the
responsibility of an individual development project,
the Project would not conflict with implementation
of the LCFS.

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Table 4-10 (continued)
Project Consistency with Applicable State Renewable Energy and Energy Efficiency Strategies Plan Category Description Consistency Analysis
Advanced
Clean Cars
(ACC)
Program
In 2012, the California Air Resources
Board (CARB) adopted the ACC program
to reduce criteria pollutant emissions
and GHG emissions for model year
vehicles 2015 through 2025. ACC
includes the Low-Emission Vehicle (LEV)
regulations that reduce criteria
pollutants and GHG emissions from lightand medium-duty vehicles, and the ZeroEmission Vehicle (ZEV) regulations that require manufacturers to produce an
increasing number of pure ZEVs
(meaning battery electric and fuel cell
electric vehicles), with provisions to also
produce plug-in hybrid electric vehicles
(PHEV) in the 2018 through 2025 model
years. In 2022, CARB developed the ACC
II regulations which seeks to reduce
criteria and greenhouse gas emissions
from new light- and medium-duty
vehicles beyond the 2025 model year,
and increase the number of ZEVs for
sale. On December 18, 2024, the USEPA
granted a waiver for California’s ACC II
regulation.

Consistent. The Project would not conflict with
implementation of the ACC program. The United
States Congress and Senate voted to disapprove
California’s Clean Air Act waivers for Advanced Clean
Cars II using the Congressional Review Act (CRA) in
late May 2025. In response to this action, CARB
stated that they “will pursue every remedy available
to challenge these actions.”
Advanced
Clean Trucks
(ACT)
In 2021, the CARB adopted the ACT
regulation to accelerate the market for
on-road zero-emission vehicles and to
reduce emissions of oxides of nitrogen
(NOx), fine particulate matter (PM),
other criteria pollutants, toxic air
contaminants, and GHG from mediumand heavy-duty on-road vehicles. ACT applies to any manufacturer that
certifies on-road vehicles over 8,500 lbs.
gross vehicle weight rating for sale in
California unless specified as exempt.

Consistent. The Project would not conflict with
implementation of the ACT regulation. The United
States Congress and Senate voted to disapprove
California’s Clean Air Act waivers for Advanced Clean
Trucks using the Congressional Review Act (CRA) in
late May 2025. In response to this action, CARB
stated that they “will pursue every remedy available
to challenge these actions.”
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Table 4-10 (continued)
Project Consistency with Applicable State Renewable Energy and Energy Efficiency Strategies Plan Category Description Consistency Analysis
Advanced
Clean Fleets
(ACF)
In October 2022, CARB approved the
Advanced Clean Fleets (ACF) regulation,
which has requirements for fleets to
phase in the use of ZEVs from 2024 to
2042 and beyond. The fleets required to
comply with the regulation include State
and local government agency fleets, high
priority and federal fleets, and drayage
fleets. The regulation also includes a
requirement for manufacturers to only
sell zero-emission trucks starting in
2036. The ACF regulation is meant to
complement the ACT regulation and will
contribute to meeting the goals set out
in Governor Newsom’s Executive Order
N-79-20.

Consistent. The Project would not conflict with
implementation of the ACF regulation. In January
2025, CARB withdrew its request for authorization of
this rule from the USEPA.

Transport
Refrigeration
Unit (TRU) Air
Toxic Control
Measure
(ATCM)
CARB adopted the ATCM for TRUs, TRU
generator sets, and facilities where TRUs
and TRU generator sets operate in 2004
(amendments in 2010, 2011, and 2022)
to reduce diesel particulate matter
emissions from diesel-powered TRUs
and TRU generator sets.

Consistent. The Project would comply with all
applicable requirements of the TRU ATCM. In January
2025, CARB withdrew its request to the USEPA for
authorization of parts of this rule that require TRU
owners to turnover at least 15 percent of their dieselfueled truck TRU fleet to ZE TRU by December 31, 2023, and each year thereafter.

SB 375 SB 375 establishes mechanisms for the
development of regional targets for
reducing passenger vehicle GHG
emissions. Under SB 375, CARB is
required, in consultation with the State’s
Metropolitan Planning Organizations, to
set regional GHG reduction targets for
the passenger vehicle and light-duty
truck sector for 2020 and 2035.

Consistent. Although this goal is not the
responsibility of an individual development project,
the Project would not conflict with the
implementation of SB 375; refer to Section VIII,
Greenhouse Gas Emissions.

Source: Ramboll Americas Engineering Solutions, Inc., Foothill Ranch Costco Project Energy Technical Report, December 2025.

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VII. Geology and Soils
Would the project:

1. Rupture of a known earthquake fault, as
delineated on the most recent AlquistPriolo 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. No Yes No No

2. Strong seismic ground shaking? No Yes Yes No

3. Seismic-related ground failure,
including liquefaction? No Yes No No

4. Landslides? No Yes Yes No
b. Result in substantial soil erosion or the loss
of topsoil? No Yes No No
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?
No Yes No No
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?
No Yes Yes No
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 waste water?
No Yes No No
f. Directly or indirectly destroy a unique
paleontological resource or site or unique
geologic feature?
No Yes Yes No
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This section is based in part on the Geotechnical Study (Revised) Proposed Costco Wholesale Warehouse 26602 Towne Centre Drive Foothill Ranch, California (Geotechnical Study) prepared by Kleinfelder, dated April 4, 2025 (Revised November 21, 2025), included in its entirety as Appendix D, Geotechnical Study.

Discussion: The 2040 General Plan FEIR determined that impacts to geology and soils would be less than significant through the implementation of policies and actions in the 2040 General Plan. a) Directly or indirectly cause potential substantial adverse effects, including the risk of loss, injury, or death involving:
1) 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.

As discussed in the 2040 General Plan FEIR, there are no known active or potentially active faults, or Alquist-Priolo Earthquake Fault Zones, located within Lake Forest. The Geotechnical Study confirms that the Project site is not within a currently established Alquist-Priolo Earthquake Fault Zone. The nearest mapped Earthquake Fault Zone to the Project site is the Glen Ivy Segment of the Elsinore fault, located approximately 11.4 miles to the northeast. Additionally, the San Joaquin Hills Blind Thrust Fault is approximately 4.2 miles southwest of the Project site and, while it is not mapped under the Alquist-Priolo Act as an Earthquake Fault Zone and does not present a potential for surface fault rupture, is an important fault with respect to geologic hazards. As indicated in the Geotechnical Study, there are no known faults within the Project site. Therefore, the Project would not directly or indirectly cause potential substantial adverse effects involving rupture of a known earthquake fault; impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.
2) Strong Seismic Ground Shaking
As indicated in the Geotechnical Study, there are several faults within Southern California that are capable of producing large earthquakes. The nearest Holocene-active faults near the Project site include the San Joaquin Hills thrust, Glen Ivy segment of the Elsinore Fault, Newport-Inglewood, San Jacinto, and San Andreas, located approximately 4.2 miles southwest, 11.4 miles northwest, 16.7 miles southwest, 33.9 miles northeast, and 41.0 miles northeast, respectively. The Geotechnical Study concludes that because the Project site is located in the seismically active southern California region, the site could be subjected to moderate to strong ground shaking in the event of an earthquake on one of the many active southern California faults.

The City of Lake Forest has adopted the California Building Code (Municipal Code Chapter 8.02), with amendments, which prescribes regulations for the erection, construction, enlargement, alteration, repair, improving, removal, conversion, demolition, occupancy, equipment, use, height, area and maintenance of all buildings and structures. The California Building Code (CBC) includes standards related to soils and foundations, structural design, building materials, and structural testing and inspections to minimize hazards during a seismic event. The Project would be required to comply with the applicable regulations in the CBC, which would reduce potential impacts associated with strong seismic ground shaking, as well Item: 11
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as the Geotechnical Study prepared for the Project, which includes site-specific geotechnical design recommendations. The City of Lake Forest Building Division would review Project construction plans for compliance with the Geotechnical Study, CBC, and the Lake Forest Municipal Code. Thus, compliance with the City’s established regulatory framework and standard engineering practices and design criteria, which would be verified through the City’s construction plan review process would ensure potential impacts associated with strong seismic ground shaking at the Project site would be reduced to a less than significant impact, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.
3) Seismic-Related Ground Failure, Including Liquefaction The term liquefaction describes a phenomenon in which saturated, cohesionless soils temporarily lose shear strength (liquefy) due to increased pore water pressures induced by strong, cyclic ground motions during an earthquake. Structures founded on or above potentially liquefiable soils may experience bearing capacity failures due to the temporary loss of foundation support, vertical settlements (both total and differential), and/or undergo lateral spreading. The factors known to influence liquefaction potential include soil type, relative density, grain size, confining pressure, depth to groundwater, and the intensity and duration of the seismic ground shaking. Liquefaction is most prevalent in loose to medium dense, silty, sandy, and gravelly soils below the groundwater table.

Seismic compression results from the accumulation of contractive volumetric strains in unsaturated soil during earthquake shaking. Loose to medium dense granular material with no fines or with low plasticity fines are most susceptible to seismic compression. Based on the density and soil composition of the underlying soils, the Geotechnical Report concludes that the potential for seismic compression (dynamic dry settlement) is considered to be very low.

As indicated in the Geotechnical Study, the Project site is not located within a State hazard zone for liquefaction. Because of the lack of groundwater and the soil types at the site, the Geotechnical Study concludes that the potential for liquefaction is not considered a hazard at the site. Therefore, impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.
4) Landslides
A landslide results from the downgradient movement of earth material along a slope or hillside. Landslides occur on slopes when soil and base material lose strength, typically from an increase in pore-water pressures and the forces of gravity, causes the soil and base material to move down-gradient. Landslides can result from a variety or combination of root causes such as steepness of slope, type of material, water content of slope soils, amount and type of vegetation, and major natural hazards such as earthquakes, volcanic eruptions, wildfires, and floods. Steeper slopes and weaker rocks are the most vulnerable to mass wasting events. Landslides can occur as slow but progressive movements of soil over time or from the rapid deterioration of soil on a slope. They are frequently triggered by intense rainfall or seismic shaking.

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As indicated in the Geotechnical Study, a portion of the site is located within a State-designated Seismic Hazard Zone for Earthquake Induced-Landslides. The California Geological Survey and California Department of Conservation Landslide Inventory online database shows the same landslide and describes it as a dormant mature/old/relict rock slide that had failed from near to the northwest. More specifically, the landslide failed from the northwest boundary of the site into a small tributary to Borrego Canyon Wash. According to historical photographs, grading of the site as early as 1994 levelled the site. No evidence of the landslide remains. No evidence of distress was observed at the time of the geotechnical investigation conducted as part of the Geotechnical Study. The Geotechnical Study concludes that the risk from landslides and other forms of mass wasting is considered low due to the lack of significant slopes at the site.

Temporary excavations associated with construction activities may result in temporary slopes. The Geotechnical Study provides recommendations during construction activities associated with site preparation and excavations. The City of Lake Forest Building Division would review Project construction plans for compliance with the Geotechnical Study, CBC, and the Lake Forest Municipal Code. Thus, compliance with the City’s established regulatory framework and standard engineering practices and design criteria, which would be verified through the City’s construction plan review process, would ensure potential impacts associated with temporary slopes within the Project site would be reduced to a less than significant impact, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.
b) Result in substantial soil erosion or the loss of topsoil? Grading and earthwork activities associated with Project construction would expose soils to potential short-term erosion by wind and water. Project construction activities would be required to comply with applicable City water quality measures, including the Lake Forest Grading and Excavation Code (Lake Forest Municipal Code Chapter 8.30) and Municipal Code Chapter 15.14, Stormwater Quality Management, which include conditions and requirements established by the City related to the reduction or elimination of storm water runoff pollutants during construction and operation of the Project.

The Project site is currently developed with a commercial building, paved parking areas, and landscaping.

Development of the Project would reduce the total impervious area from 94 percent in the existing condition to 93 percent in the proposed condition due to increased landscaping. The Project would install inlets to capture and convey stormwater into a biofiltration BMP and convey treated flows into a proposed underground detention system; refer to Section X, Hydrology and Water Quality. The Project would be required to implement operational-level BMPs in accordance with the Project’s Preliminary Water Quality Management Plan (WQMP) (refer to Section X). Following compliance with the established regulatory framework identified in the Lake Forest Municipal Code regarding stormwater and runoff pollution control and implementation of the Project’s WQMP, potential impacts associated with soil erosion and the loss of topsoil would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.

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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?
Refer to the discussion above related to landslides and liquefaction. As demonstrated, the Project would not result in significant impacts related to landslides or liquefaction.

Liquefaction may induce lateral spreading, which is a type of ground deformation that occurs when surface material extends or spreads on gentle slopes.9 Areas identified to have high liquefaction susceptibility or areas with a sloping terrain may be vulnerable to lateral spreading. As the Geotechnical Study concludes that the potential for liquefaction is not considered a hazard at the site due to a lack of groundwater and the soil types at the site, lateral spreading is similarly not considered to be a hazard.

Ground subsidence is a gradual settling or sudden sinking of the earth's surface owing to subsurface movement of earth materials. Ground subsidence results from fluid (water or petroleum) extraction from underlying sediments and/or formations, which causes the collapse of pore spaces previously occupied by the removed fluid. The collapse of these pore spaces compacts the underlying formations leading to a gradual drop in ground surface elevation. Ground subsidence is most often found in areas where large volumetric withdrawals of fluids from underground reservoirs has occurred or is ongoing. Ground shaking from tectonic activity can exacerbate the vertical sinking of land in an area over the withdrawal site.

Structures and improvements located in subsidence-prone areas are at risk for damage if subsidence were to occur.

As indicated in the Geotechnical Study, most of the subsidence in the State of California has resulted from excessive groundwater pumping for municipal, industrial, and agricultural uses, although oil extraction is also a documented cause. A review of the United States Geological Survey (USGS) subsidence interactive online map conducted as part of the Geotechnical Study shows the Project site is not documented to be experiencing subsidence. Further, neither current on-site operations, nor proposed operations associated with the Project would include activities known to cause subsidence, such as groundwater extraction.

The Geotechnical Study provides site-specific geotechnical design and construction recommendations based on CBC seismic design standards in place at the time of the report. The recommendations within the Geotechnical Study would provide protection for the proposed development to the extent required to reduce seismic risk to an acceptable level as defined by the California Code of Regulations. The proposed Project would be required to comply with the Geotechnical Study prepared for the Project and the CBC, as adopted by Lake Forest Municipal Code Chapter 8.02. The CBC includes standards related to soils and foundations, structural design, building materials, and structural testing and inspections to minimize geotechnical hazards. The City of Lake Forest Building Division would review Project construction plans for compliance with the Geotechnical Study, CBC, and the Lake Forest Municipal Code. Thus, compliance with the City’s established regulatory framework and standard engineering practices and design criteria, which would be verified through the City’s construction plan review process would ensure potential impacts associated with a geologic unit or soil that is unstable or would become unstable at the Project site would be reduced to a less than significant impact, consistent with the 2040 General Plan FEIR. 9 United States Geological Survey, Lateral Spread, https://www.usgs.gov/media/images/lateral-spread, accessed December 12, 2025.

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Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. 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? Expansive soils are characterized by their ability to undergo significant volume changes (shrink or swell) due to variations in moisture content. Changes in soil moisture content can result from precipitation, landscape irrigation, utility leakage, roof drainage, perched groundwater, drought, or other factors, and may result in unacceptable settlement or heave of structures or concrete slabs supported on grade.

The surficial soils at the Project site are generally silty to clayey sands overlying sandstone and do not undergo significant volume changes when exposed to various moisture contents. Accordingly, the Geotechnical Study concludes that expansion potential of the near surface soils is considered low.

The Geotechnical Study includes site-specific construction and design recommendations that address identified potential geologic and soil hazards. The proposed Project would be required to comply with the Geotechnical Study prepared for the Project and the CBC, as adopted by Lake Forest Municipal Code Chapter 8.02. The CBC includes standards related to soils and foundations, structural design, building materials, and structural testing and inspections to minimize geotechnical hazards. The City of Lake Forest Building Division would review Project construction plans for compliance with the Geotechnical Study, CBC, and the Lake Forest Municipal Code. Thus, compliance with the City’s established regulatory framework and standard engineering practices and design criteria, which would be verified through the City’s plan review process, would reduce potential impacts associated with expansive soils at the Project site. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. 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 waste water? The Project site is currently served by the City’s sewer system and would continue to be served by the existing sewer system under the Project. The Project would not involve the use of septic tanks or alternative wastewater disposal systems and would have no impact relative to septic tanks or alternative wastewater disposal systems, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.
f) Directly or indirectly destroy a unique paleontological resource or site or unique geologic feature?
Significant paleontological resources are determined to be fossils or assemblages of fossils that are unique, unusual, rare, uncommon, or diagnostically important. Significant fossils can include remains of large to very small aquatic and terrestrial vertebrates or remains of plants and animals previously not represented in certain portions of the stratigraphy. Assemblages of fossils that might aid stratigraphic Item: 11
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correlation, particularly those offering data for the interpretation of tectonic events, geomorphologic evolution, and paleoclimatology is also critically important.

According to the 2040 General Plan FEIR, it is possible that undiscovered paleontological resources could be encountered during ground-disturbing activities within the City. The 2040 General Plan FEIR concluded that this would be a potentially significant impact, which would be mitigated to a less than significant level through the implementation of the policies and actions in the 2040 General Plan.

The Project site is currently developed and has been extensively altered by previous ground disturbance associated with development of the Project site and larger Foothill Ranch Towne Centre. The Project site is underlain by approximately four to 9.5 feet of artificial fill underlain by Capistrano Formation sandstone.

Minimal grading, resulting in cuts of less than two feet and fills of less than six feet, are anticipated to occur within the Project site. Due to the extensive ground disturbance that occurred within the Project site and surrounding area associated with construction of the existing development, the presence of artificial fill materials within the site, and the minimal grading and excavation that would occur with the proposed Project, the likelihood of encountering paleontological resources in the Project site is anticipated to be low. In the unlikely event that buried resources are encountered during ground disturbance activities, the General Plan includes policies and actions that reduce impacts to paleontological resources. Specifically, General Plan Action RR-3d would require all new development, infrastructure, and other ground-disturbing projects to stop all work if construction or grading activities result in the discovery of paleontological resources and that the resources be examined by a qualified paleontologist. Thus, similar to the conclusions of the 2040 General Plan FEIR, potential impacts pertaining to the direct or indirect destruction of a unique paleontological resource or site or unique geologic feature would be less than significant. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.

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VIII. Greenhouse Gas Emissions
Would the project:

Discussion: The 2040 General Plan FEIR determined that impacts to greenhouse gas (GHG) emissions would be less than significant through the implementation of policies and actions in the 2040 General Plan.

REGULATORY FRAMEWORK
The following section summarizes pertinent federal, State, and local regulations related to GHGs.

U.S. Environmental Protection Agency Endangerment Finding The USEPA’s authority to regulate GHG emissions stems from the US Supreme Court decision in Massachusetts v. EPA (2007). The Supreme Court ruled that GHGs meet the definition of air pollutants under the existing Clean Air Act and must be regulated if these gases could be reasonably anticipated to endanger public health or welfare. Responding to the Court’s ruling, the USEPA finalized an endangerment finding in December 2009. Based on scientific evidence it found that six GHGs (CO2, CH4, N2O, HFCs, PFCs, and SF6) constitute a threat to public health and welfare. Thus, it is the Supreme Court’s interpretation of the existing FCAA and the USEPA’s assessment of the scientific evidence that form the basis for the USEPA’s regulatory actions.

On July 29, 2025, the USEPA proposed to rescind the 2009 GHG endangerment finding. Absent this finding, the USEPA lacks statutory authority under Section 202 of the FCAA to prescribe standards for GHG emissions. Therefore, the USEPA also proposed to remove GHG regulations for light-, medium-, and heavy-duty on-highway vehicles. However, the USEPA intends to retain, without modification, regulations necessary for criteria pollutant and air toxic measurement and standards, Corporate Average Fuel Economy (CAFE) testing, and associated fuel economy labeling requirements.

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Assembly Bill 32 (California Global Warming Solutions Act of 2006) The California Global Warming Solutions Act of 2006 (AB 32; California Health and Safety Code Division

25.5, Sections 38500-38599) establishes regulatory, reporting, and market mechanisms to achieve quantifiable reductions in GHG emissions and establishes a cap on statewide GHG emissions. AB 32 required that statewide GHG emissions be reduced to 1990 levels by 2020 (this goal has been met). In order to achieve this reduction mandate, AB 32 required CARB to adopt rules and regulations to achieve the maximum technologically feasible and cost-effective GHG reductions.

Senate Bill 375
SB 375, signed in September 2008 (Chapter 728, Statutes of 2008), aligns regional transportation planning efforts, regional GHG reduction targets, and land use and housing allocations. SB 375 requires Metropolitan Planning Organizations (MPOs) to adopt a SCS or alternative planning strategy (APS) that will prescribe land use allocation in that MPO’s regional transportation plan. CARB, in consultation with MPOs, is required to provide each affected region with GHG reduction targets emitted by passenger cars and light trucks in the region for the years 2020 and 2035. These reduction targets are to be updated every eight years but can be updated every four years if advancements in emissions technologies affect the reduction strategies to achieve the targets. CARB is also charged with reviewing each MPO’s SCS or APS for consistency with its assigned targets. If MPOs do not meet the GHG reduction targets, transportation projects may not be eligible for funding.

Executive Order S-3-05
Executive Order S-3-05 set forth a series of target dates by which Statewide emissions of GHGs would be progressively reduced, as follows:
• By 2010, reduce GHG emissions to 2000 levels;
• By 2020, reduce GHG emissions to 1990 levels; and
• By 2050, reduce GHG emissions to 80 percent below 1990 levels.

Executive Order S-3-05 directed the California Environmental Protection Agency (Cal/EPA) Secretary to coordinate a multi-agency effort to reduce GHG emissions to the target levels. The Secretary is required to submit biannual reports to the Governor and California Legislature describing the progress made toward the emissions targets, the impacts of global climate change on California’s resources, and mitigation and adaptation plans to combat these impacts. To comply with Executive Order S-3-05, the Cal/EPA Secretary created the California Climate Action Team, made up of members from various State agencies and commissions. The Climate Action Team released its first report in March 2006, which proposed to achieve the targets by building on the voluntary actions of California businesses, local governments, and communities and through State incentive and regulatory programs.

Title 24, Part 6
The California Energy Efficiency Standards for Residential and Nonresidential Buildings, Title 24, Part 6 of the California Code of Regulations (CCR) and commonly referred to as the “Energy Code” or “Title 24” were established in 1978 in response to a legislative mandate to reduce California’s energy consumption.

Part 6 of Title 24 requires the design of building shells and building components to conserve energy. The Item: 11
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standards are updated periodically to allow consideration and possible incorporation of new energy efficiency technologies and methods. The 2025 Energy Code standards took effect on January 1, 2026.

Title 24, Part 11
The California Green Building Standards Code (CCR Title 24, Part 11), commonly referred to as CALGreen, is a Statewide mandatory construction code developed and adopted by the California Building Standards Commission and the Department of Housing and Community Development. CALGreen also provides voluntary tiers and measures that local governments may adopt that encourage or require additional measures in five green building topical areas. The 2025 CALGreen Code went into effect on January 1, 2026.

Senate Bill 32
Signed into law on September 2016, SB 32 codifies the 2030 GHG reduction target in Executive Order B30-15 (40 percent below 1990 levels by 2030). SB 32 authorizes CARB to adopt an interim GHG emissions level target to be achieved by 2030. CARB also must adopt rules and regulations in an open public process to achieve the maximum, technologically feasible, and cost-effective GHG reductions.

CARB Scoping Plan
On December 11, 2008, CARB adopted its Climate Change Scoping Plan (Scoping Plan), which functions as a roadmap of CARB’s plans to achieve GHG reductions in California required by Assembly Bill (AB) 32 through subsequently enacted regulations. The Scoping Plan contains the main strategies California will implement to reduce carbon dioxide-equivalent (CO2e) emissions by 169 million metric tons (MMT), or approximately 30 percent, from the State’s projected 2020 emissions level of 596 MMT of CO2e under a business-as-usual scenario. The Scoping Plan also breaks down the amount of GHG emissions reductions CARB recommends for each emissions sector of the State’s GHG inventory.

CARB updated the Scoping Plan in 2013 and again in 2017. The 2013 Update built upon the initial Scoping Plan with new strategies and recommendations, and also set the groundwork to reach the long-term goals set forth by the State. Successful implementation of existing programs (as identified in previous iterations of the Scoping Plan) has allowed California to meet the 2020 target. The 2017 Update expanded the scope of the plan further by focusing on the strategy for achieving the State’s 2030 GHG target of 40 percent emissions reductions below 1990 levels (to achieve the target codified into law by SB 32), and substantially advanced toward the State’s 2050 climate goal to reduce GHG emissions by 80 percent below 1990 levels.

The 2017 Update relied on the preexisting programs paired with an extended, more stringent Cap-andTrade Program, to deliver climate, air quality, and other benefits. The 2017 Update identified new technologically feasible and cost-effective strategies to ensure that California meets its GHG reduction goals.

CARB adopted the 2022 Scoping Plan Update (2022 Scoping Plan) on December 15, 2022. The 2022 Scoping Plan assesses progress towards the SB 32 GHG reduction target of at least 40 percent below 1990 emissions by 2030, while laying out a path to achieving carbon neutrality no later than 2045 and a reduction in anthropogenic emissions by 85 percent below 1990 levels. Unlike the 2017 Scoping Plan, CARB no longer includes a numeric per capita threshold and instead advocates for compliance with a local GHG reduction strategy (CAP) consistent with CEQA Guidelines section 15183.5.

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SCAG Regional Transportation Plan and Sustainable Communities Strategy (RTP/SCS) As previously discussed, SB 375 required MPOs such as SCAG to incorporate a Sustainable Communities Strategy into its Regional Transportation Plan (RTP) that achieves the GHG emission reduction targets set by CARB. SCAG’s Sustainable Communities Strategy was first included in the 2016 RTP/SCS, which was adopted by SCAG in April 2016. The original plan has since been superseded by SCAG’s 2024-2050 RTP/SCS, also known as Connect SoCal 2024, which was certified by CARB in August 2025.

In general, the goals and policies of the Sustainable Communities Strategy are to improve mobility, accessibility, reliability, efficiency, livability, sustainability, and equity. The RTP/SCS adopted by SCAG is expected to reduce GHG emissions from automobiles and light-duty trucks and achieve the GHG emissions reduction target for the region set by the CARB (Govt. Code Section 65080(b)(2)(B)).

THRESHOLDS OF SIGNIFICANCE
The GHG Report assesses significance of GHG impacts based on Section VIII, Greenhouse Gases, of Appendix G of the CEQA Guidelines. In the absence of a quantitative GHG threshold from SCAQMD, GHG impacts for the first threshold are assessed based on the tiered approach presented in SCAQMD’s Interim CEQA GHG Significance Threshold for Stationary Sources, Rules and Plan (“SCAQMD Interim GHG Threshold”). Specifically, with respect to Tier 3, SCAQMD estimated that a screening level of 3,000 MT CO2e/yr would capture 90 percent of GHG emissions from new residential and commercial projects. For the purposes of evaluating against Threshold 1, the Tier 3 screening level for residential and commercial projects, 3,000 MT CO2e/yr, was used to determine if the Project would generate GHG emissions that may have a significant impact on the environment. For the second threshold, significance is assessed based on whether the proposed Project would conflict with the CARB 2022 Scoping Plan, the current RTP/SCS for SCAG, or the City of Lake Forest General Plan. a) Generate greenhouse gas emissions, either directly or indirectly, that may have a significant impact on the environment?
The City developed the 2040 General Plan to achieve local per capita GHG emissions levels that would be consistent with the statewide reduction targets established by AB 32, SB 32, and the CARB’s 2017 Scoping Plan. As discussed in the 2040 General Plan FEIR, upon adoption of the 2040 General Plan and implementation of the policies and actions, the City of Lake Forest would not exceed the per capita GHG emission targets established to ensure compliance with SB 32 and other California legislation for future year 2030 and 2040 General Plan buildout year 2040. Therefore, the 2040 General Plan FEIR concluded that the 2040 General Plan would not generate GHG emissions, either directly or indirectly, that may have a significant impact on the environment and there would be a less than significant impact following adoption and implementation of the policies and actions in the 2040 General Plan.

The following discussion provides calculated levels of construction and operational GHG emissions associated with the proposed Project, based on commonly used modelling software (i.e., CalEEMod v.2022.1). CalEEMod utilizes widely accepted models for emission estimates combined with appropriate default data that can be used if site-specific information is not available. The GHG Report uses default factors for the Orange County area for the emissions inventory, unless otherwise noted; refer to Appendix E. It should be noted that many of the assumptions provided by CalEEMod are conservative and do not account for many of the Project design features. For example, the Project would include 12 EV stalls which would reduce the operational GHG emissions beyond the levels modeled in this analysis by replacing Item: 11
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conventionally fueled VMT with EV miles traveled. In addition, the Project proposes to install solar panels which would generate renewable electricity and displace some of the electricity used by the Project. This would further reduce the operational GHG emissions beyond levels modeled in this analysis by decreasing the average carbon intensity of the electricity used by the Project.

The proposed Project would generate GHGs during the construction and operational phases of the Project. Total GHG emissions for the proposed Project construction are summarized in Table 4-11, Annual Average GHG Emissions. For construction phase Project emissions, GHGs are quantified and amortized over the life of the Project.10 To amortize the emissions over the life of the Project, the SCAQMD recommends calculating the total GHG emissions for the construction activities, dividing it by a 30-year Project life then adding that number to the annual operational phase GHG emissions. As such, Project construction emissions were amortized over a 30-year period and added to the annual operational phase GHG emissions.

As shown in Table 4-11, the Project’s annual operational GHG emissions were estimated to be 932 MT CO2e per year. The amortized construction emissions were added to the Project’s annual operational GHG emissions, and the combined emissions were estimated to be 962 MT CO2e per year. These emissions are below SCAQMD’s draft GHG emissions screening level (3,000 MT CO2e/yr). Therefore, the GHG emissions associated with the construction and operation of the proposed Project would not have a significant impact on the environment. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR.

No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. 10 The Project lifetime is based on SCAQMD’s standard 30-year assumption (South Coast Air Quality Management District, Minutes for the GHG CEQA Significance Threshold Stakeholder Working Group #13, August 26, 2009).

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Table 4-11
Annual Average GHG Emissions
Emissions Category Average GHG Emissions
(MT CO2e/yr)1
Area Sources 3.4
Energy Usage 326
Mobile 348
Stationary Sources 5.1
Water 28
Waste Disposed 222
Refrigerant 0.1
Vegetation -0.17
Operational Sub-Total 932
Construction Amortized2 29.7
Total Emissions3 962
SCAQMD Draft Screening Level 3,000
Exceeds Threshold? No
Source: Ramboll Americas Engineering Solutions, Inc., Foothill Ranch Costco Project Greenhouse Gas Emissions Technical Report, December 2025.

Notes:

1. Emissions are presented as CO2e, which include CO2, CH4, and N2O emissions, weighted by their respective global warming potentials.

2. One-time emissions from construction was amortized over a 30-year period.

3. Sum of amortized one-time emissions and operational sub-total emissions. b) Conflict with an applicable plan, policy or regulation adopted for the purpose of reducing the emissions of greenhouse gases?
The 2040 General Plan FEIR concluded that the 2040 General Plan would be consistent with the CARB’s 2017 Scoping Plan, and thus all current statewide GHG reduction laws (i.e., AB 32 and SB 32) relevant to the 2040 General Plan that have been adopted to reduce GHG emissions. The 2040 General Plan would reduce emissions to below the per capita thresholds through buildout of the 2040 General Plan (i.e., for years 2030 and 2040), which ensures that the 2040 General Plan is consistent with all GHG reduction targets established for the state. Therefore, the 2040 General Plan FEIR concluded that the 2040 General Plan would not conflict with the State of California’s GHG reduction goals and targets. The 2040 General Plan FEIR ultimately concluded that the 2040 General Plan would not conflict with an applicable plan, policy, or regulation adopted for the purpose of reducing the emissions of greenhouse gases and impacts would be less than significant.

The discussion below analyzesthe Project’s consistency with CARB’s 2022 Scoping Plan, SCAG’s 2024-2050 RTP/SCS (Connect SoCal 2024), and the City of Lake Forest 2040 General Plan.

CARB’s 2022 Scoping Plan Consistency
The 2022 Scoping Plan contains a table of priority GHG reduction strategies that can be utilized by local governments. The three main priority areas addressed are Transportation Electrification, VMT Reduction, Item: 11
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and Building Decarbonization.11 These measures represent the core strategies that local jurisdictions in California can implement to reduce GHGs in alignment with State goals.

As discussed below and shown in Table 4-12, Project Consistency with the CARB’s 2022 Scoping Plan, the proposed Project would be consistent with the 2022 Scoping Plan. The Project would include 12 EV stalls for plug-in electric vehicles as part of the Project design. This directly supports the Transportation Electrification priority area by providing a convenient, low-cost EV charging station to members which would in turn replace conventionally fueled VMT with EV miles traveled.

The second priority area of the Scoping Plan is VMT Reduction. As discussed in the TIS Technical Memo, the Project would result in a net reduction in VMT across the region by shifting a proportion of existing warehouse trips to other existing Costco locationsto a new, more convenient (i.e., shorter travel distance) location. Additionally, the Project would be an infill development project located adjacent to existing commercial development and would therefore support the preservation of natural and working lands and compact infill development.

The Project includes a number of measures to reduce energy usage and incorporates sustainability features consistent with Title 24 energy requirements. The Project would comply with CALGreen requirements, which include a number of green building practices to reduce energy use. These practices are listed below and would further support the Building Decarbonization priority area of the 2022 Scoping Plan.
• Parking lot light standards are designed in order to provide even light distribution, and utilize less energy compared to a greater number of fixtures at lower heights. The use of LED lamps provides a higher level of perceived brightness with less energy than other lamps such as high pressure sodium.
• New and renewable building materials are typically extracted and manufactured within the region.
• The use of pre-manufactured building components, including structural framing and metal panels, helps to minimize waste during construction.
• Pre-manufactured metal wall panels with insulation carry a higher R-Value and greater solar reflectivity to help conserve energy. Building heat absorption is further reduced by a decrease in the thermal mass of the metal wall when compared to a typical masonry block wall. • Costco uses a reflective cool roof material to produce lower heat absorption and thereby lowering energy requirements during the hot summer months. This roofing material meets the requirements for the EPA’s Energy Star energy efficiency program. • The irrigation system includes the use of deep root watering bubblers for parking lot trees to minimize usage and ensure that water goes directly to the intended planting areas. • Storm water management plans are designed to maintain quality control and storm water discharge rates.
11 California Air Resources Board, Final 2022 Scoping Plan Update and Appendices, December 2022, https://ww2.arb.ca.gov/our-work/programs/ab-32-climate-change-scoping-plan/2022-scoping-plan-documents, accessed December 23, 2025.

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• Use of native species vegetation and drip irrigation systems greatly reduces potable water consumption.
• High-efficiency restroom fixtures achieve a 40% decrease and water savings over U.S. standards by using high-efficient restroom fixtures.
• Commissioning of mechanical systems to ensure the system is functioning as designed. • HVAC comfort systems are controlled by a computerized building management system to maximize efficiency.
• HVAC units are high-efficiency direct ducted units.
• HVAC units have phased out the use of hydrochlorofluorocarbons completely. Long before the Montreal Protocol timeline.
• Parking lot and exterior lights are controlled by a centrally controlled Energy Management system. • Lighting is controlled by the overall Project energy management system. • High-efficiency light source and ballasts (LED) and bi-level switching for fluorescent fixtures are used.
• Energy efficient Transformers.
• Use of variable speed motors on make-up air units and booster pumps. • Gas water heaters are direct vent and 94% efficient or greater. • Main Building structure is a pre-engineered system that uses 100% recycled steel materials and is designed to minimize the amount of material utilized.
• Roof material is recycled standing seam metal panel, designed to maximum efficiency for spanning the structure.
• When masonry and concrete are used, the materials purchased are local to the Project minimizing the transportation and impact to local road networks.
• Construction waste is recycled whenever possible.
• Floor sealant is No-VOC and represents over 80% of the floor area. • CO2 is monitored throughout the warehouse.
• Extensive recycling/reuse program is implemented for warehouse and office space including tires, cardboard, grease, plastics, and electronic waste.
• Use of plastic shopping bags is avoided.
• Suppliers are required to reduce packaging and consider alternative packaging solutions. • Distribution facilities are strategically located to minimize miles traveled for delivery. Deliveries are made in full trucks.
• All Costco trucks are equipped with an engine idle shut off timer.

Further, the Project would install solar panels which would generate renewable electricity and displace some of the electricity used by the Project. This would support the Building Decarbonization priority area as well by decreasing the average carbon intensity of the electricity used by the Project.

Based on the Project elements described above, and the consistency analysis presented in Table 4-12, the Project would not interfere with the implementation of the 2022 Scoping Plan and would include elements that support the goals of the plan.

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Table 4-12
Project Consistency with the CARB’s 2022 Scoping Plan
Priority GHG Reduction Strategies Consistency Analysis
Transportation Electrification
Convert local government fleets to ZEVs and
provide EV charging at public sites
Consistent. Although this goal is not the responsibility of an individual development project, the Project includes 12 EV stalls which would provide Costco members with convenient EV charging at a lower cost.

Create a jurisdiction-specific ZEV ecosystem to
support deployment of ZEVs statewide (such as
building standards that exceed state building
codes, permit streamlining, infrastructure
siting, consumer education, preferential
parking policies, and ZEV readiness plans)
VMT Reduction
Reduce or eliminate minimum parking
standards
Consistent. Although this goal is not the responsibility of an individual commercial development project, according to the TIS Technical Memo, the Project would result in a net negative VMT impact, therefore supporting the VMT reduction priority area of the Scoping Plan. Furthermore, the Project is located on a parcel that is adjacent to existing infrastructure and development. The Project is expected to serve the existing population of the area by providing more convenient access to Costco services and would allow customers to have multiple needs served in one trip, including but not limited to: eye exams, purchase of household goods and groceries, and tire service.

Implement Complete Streets policies and
investments, consistent with general plan
circulation element requirements
Increase access to public transit by increasing
density of development near transit, improving
transit service by increasing service frequency,
creating bus priority lanes, reducing or
eliminating fares, microtransit, etc.

Increase public access to clean mobility options
by planning for and investing in electric
shuttles, bike share, car share, and walking
Implement parking pricing or transportation
demand management pricing strategies
Amend zoning or development codes to enable
mixed-use, walkable, transit-oriented, and
compact infill development (such as increasing
the allowable density of a neighborhood)
Preserve natural and working lands by
implementing land use policies that guide
development toward infill areas and do not
convert “greenfield” land to urban uses (e.g.,
green belts, strategic conservation easements)
Reduce or eliminate minimum parking
standards
Implement Complete Streets policies and
investments, consistent with general plan
circulation element requirements
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Table 4-12 (continued)
Project Consistency with the CARB’s 2022 Scoping Plan
Priority GHG Reduction Strategies Consistency Analysis
Building Decarbonization
Adopt all-electric new construction reach codes
for residential and commercial uses
Consistent. Although this goal is not the responsibility of an individual development project, as described above, the Project includes a number of energy-saving design features and would meet the CALGreen standards in effect at the time of building permit application. Further, the Project would include solar panels which would provide renewable energy to the Project and further reduce the GHG emissions associated with the building energy.

Adopt policies and incentive programs to
implement energy efficiency retrofits for
existing buildings, such as weatherization,
lighting upgrades, and replacing energyintensive appliances and equipment with more efficient systems (such as Energy Star-rated
equipment and equipment controllers)
Adopt policies and incentive programs to
electrify all appliances and equipment in
existing buildings such as appliance rebates,
existing building reach codes, or time of sale
electrification ordinances
Facilitate deployment of renewable energy
production and distribution and energy storage
on privately owned land uses (e.g., permit
streamlining, information sharing)
Deploy renewable energy production and
energy storage directly in new public projects
and on existing public facilities (e.g., solar
photovoltaic systems on rooftops of municipal
buildings and on canopies in public parking lots,
battery storage systems in municipal buildings)
Source: California Air Resources Board, 2022 Scoping Plan for Achieving Carbon Neutrality, December 2022.

SCAG’s Connect SoCal (2024-2045 RTP/SCS) Consistency
As discussed below and shown in Table 4-13, Project Consistency with SCAG’s Connect SoCal (2024-2050 RTP/SCS), the proposed Project would not conflict with the State’s GHG reduction goals and strategies as detailed in SCAG’s Connect SoCal 2024 (the current RTP/SCS for the region), which fall into four main categories: Mobility, Communities, Environment, and Economy.

As shown in Table 4-13, the proposed Project would not conflict with the implementation of Connect SoCal 2024 and has several elements that are expected to support the main categories in Connect SoCal 2024. The Project would create new employment opportunities and is located near an Orange County Transportation Authority (OCTA) bus route, therefore placing jobs that are accessible via public transit, in line with the Economy category of Connect SoCal 2024. In addition, the Project would be consistent with CALGreen standards and proposes a number of energy-saving design features, as discussed above. This would support the Environmental category of the SCAG’s Connect SoCal 2024. Lastly, per the conclusions of the TIS Technical Memo, the proposed Project would result in a net negative regional VMT and therefore would not impede the Mobility and Communities categories of the SCAG’s Connect SoCal 2024.

As such, the Project is consistent with SCAG’s Connect SoCal 2024.

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Table 4-13
Project Consistency with SCAG’s Connect SoCal (2024-2050 RTP/SCS) Regional Planning
Policy Area Regional Planning Policy Consistency Analysis Mobility: Build and maintain an integrated multimodal transportation network Complete Streets Pursue the development of Complete Streets that comprise a safe, multi modal network with
flexible use of public rights-of-way for people of
all ages and abilities using a variety of modes
(e.g., people walking, biking, rolling, driving,
taking transit)
Consistent. The Project site is located
near the Bake-Towne Centre bus stop
and is within close proximity of multiple
multifamily complexes, as well as other
shops in the Foothill Ranch Towne
Centre, therefore promoting
multimodal transit options, which
would reduce peak-hour vehicle trips.

Additionally, the Project would include
bicycle parking which would further
support multimodal transportation
options, including for employees
commuting to work.

The proposed Project is expected to
serve the existing population of the
area by providing more convenient
access to Costco services and would
allow customers to have multiple needs
served in one trip, including but not
limited to: eye exams, purchase of
household goods and groceries, and
tire service.

Facilitate the implementation of Complete
Streets and curb space management strategies
that accommodate and optimize new
technologies, micromobility devices and
first/last mile connections to transit and lastmile delivery Transit and
Multimodal
Integration
Encourage and support the implementation of
projects, both physical and digital, that facilitate
multimodal connectivity, prioritize transit and
shared mobility, and result in improved mobility,
accessibility and safety
Encourage and support the implementation of
projects, both physical and digital, that facilitate
multimodal connectivity, prioritize transit and
shared mobility, and result in improved mobility,
accessibility and safety
Transportation
System
Management
Pursue efficient use of the transportation system
using a set of operational improvement
strategies that maintain the performance of the
existing transportation system instead of adding
roadway capacity, where possible
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Table 4-13 (continued)
Project Consistency with SCAG’s Connect SoCal (2024-2050 RTP/SCS) Regional Planning
Policy Area Regional Planning Policy Consistency Analysis Communities: Develop, connect and sustain livable and thriving communities Priority
Development
Areas
Promote the growth of origins and destinations,
with a focus on future housing and population
growth, in areas with existing and planned urban
infrastructure that includes transit and utilities
Consistent. The Projectsite islocated in
the Foothill Ranch Towne Centre,
which consists of existing urban
infrastructure. The new warehouse
would provide nearby residential areas
with more convenient access to Costco
services, including eye exams,
purchases of household goods and
groceries, and tire services.

Promote the growth of origins and destinations,
in areas with a proclivity toward multi modal
options like transit and active transportation, to
reduce single occupant vehicle (SOV)
dependency and vehicle miles traveled
Consistent. The Project site is located
near existing residential areas and an
existing bus stop. The proposed Project
would include bicycle parking. The
Project would provide retail uses and
jobs near a housing-rich area served by
the OCTA, which would support
reduced vehicle trip distances. Further,
according to the TIS Technical Memo,
the Project would result in a net
negative VMT.

Seek to realize scale economies or a critical mass
of jobs and destinations in areas across the
region that can support non-SOV options and
shorter trip distances, combined trips and
reduced vehicle miles traveled
15-Minute
Communities
Promote 15-minute communities as places with
a mix of complementary land uses and accessible
mobility options that align with and support the
diversity of places (or communities) across the
region. These are communities where residents
can either access their most basic, day-to-day
needs within a 15-minute walk, bike ride or roll
from their home or as places that result in fewer
and shorter trips because of the proximity of
complementary land uses
Consistent. The proposed Project is
expected to serve the existing
population of the area by providing
more convenient access to Costco
services. The Project would be located
in a central location that is within a 15-
minute walk of the nearest residences
and would allow customers to have
multiple needs served in one trip,
including but not limited to: eye exams,
purchase of household goods and
groceries, and tire service.

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Table 4-13 (continued)
Project Consistency with SCAG’s Connect SoCal (2024-2050 RTP/SCS) Regional Planning
Policy Area Regional Planning Policy Consistency Analysis Environment: Create a healthy region for the people of today and tomorrow Sustainable
Development
Promote sustainable development and best
practices that enhance resource conservation,
reduce resource consumption and promote
resilience
Consistent. The proposed Project
would reduce energy consumption by
incorporating sustainable design
features and systems with enhanced
energy efficiencies meeting State and
federal code requirements. The
Project's proposed architectural design
fits within the Development Guidelines
and incorporates sustainable,
recyclable, durable and low
maintenance materials, and design
elements. A full list of measures is
provided above.

Support communities across the region to
advance innovative sustainable development
practices
Recognize and support the diversity of
communities across the region by promoting
local place-making, planning and development
efforts that advance equity, mobility, resilience
and sustainability
Air Quality Reduce hazardous air pollutants and greenhouse gas emissions and improve air quality
throughout the region through planning and
implementation efforts
Consistent. Although this policy is not
applicable to an individual
development project, Section III, Air
Quality, and Section VIII, Greenhouse
Gas Emissions, demonstrate that the
Project would result in less than
significant air quality and GHG impacts.

Support investments that reduce hazardous air
pollutants and greenhouse gas emissions
Reduce the exposure and impacts of emissions
and pollutants and promote local and regional
efforts that improve air quality for vulnerable
populations, including but not limited to Priority
Equity Communities and the AB 617
Communities
Clean
Transportation
Accelerate the deployment of a zero-emission
transportation system and use near-zeroemission technology to offer short-term benefits where zero-emissions solutions are not yet
feasible or commercially viable
Consistent. Although this policy is not
applicable to an individual project, the
Project would include 12 EV stalls.

Promote equitable use of and access to clean
transportation technologies so that all may
benefit from them
Natural and
Agricultural Lands
Preservation
Prioritize the climate mitigation, adaptation,
resilience and economic benefits of natural and
agricultural lands in the region
Consistent. The Project is an infill
development project with construction
occurring in a previously occupied
commercial land parcel. The Project
would not be constructed over any
natural and agricultural lands or natural
habitat and wildlife corridors. As
demonstrated in Section II, Agriculture
and Forestry Resources, and Section IV,
Biological Resources, the Project would
result in less than significant impacts to
natural and agricultural lands.

Encourage the protection and restoration of
natural habitat and wildlife corridors
Encourage the conservation and viability of
agricultural lands to protect the regional and
local food supply and ensure the sustainability of
local agriculture as a vital part of the region’s
economy
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Table 4-13 (continued)
Project Consistency with SCAG’s Connect SoCal (2024-2050 RTP/SCS) Regional Planning
Policy Area Regional Planning Policy Consistency Analysis Climate Resilience
Support local and regional climate and hazard
planning and implementation efforts for
transportation, land use, and other factors
Consistent. The Project would
incorporate an on-site storm water
management system and implement
BMPs to maintain water quality control
and storm water discharge rates.

According to the TIS Technical Memo,
the Project would result in a net
negative VMT. Further, the proposed
Project would include a number of
sustainability design elements, which
are described in detail above.

Promote sustainable water use planning,
practices and storage that improve regional
water security and resilience in a drier
environment
Consistent. The Project proposes to
include the use of native species
vegetation and drip irrigation systems
to reduce potable water consumption,
high-efficiency restroom fixtures for
greater water savings, and an on-site
storm water management system and
implementation of BMPs to maintain
quality control and storm water
discharge waters.

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Table 4-13 (continued)
Project Consistency with SCAG’s Connect SoCal (2024-2050 RTP/SCS) Regional Planning
Policy Area Regional Planning Policy Consistency Analysis Economy: Support a sustainable, efficient and productive regional economic environment that provides opportunities for all people in the region
Goods Movement
Prioritize community and environmental justice
concerns, together with economic needs, and
support workforce development opportunities,
particularly around deployment of zeroemission and clean technologies and their supporting infrastructure
Consistent. The proposed Project
would introduce a new Costco
warehouse that serves the local
community with goods and services
from both nationally known businesses
and regional and local businesses. It
would enable patrons to travel shorter
distances to access eye exams,
purchase of household goods and
groceries, and tire services, therefore
reducing emissions from vehicle travel.

Furthermore, the proposed Project
would create new jobs in the region
that are accessible via transit.

Explore and advance the transition toward zeroemission and clean technologies and other transformative technologies, where viable
Consistent. All Costco delivery trucks
would be equipped with an engine idle
shut off timer to reduce idling
emissions. Additionally, the Project
would include 12 EV stalls.

Ensure continued, significant investment in a
safe, secure, clean and efficient transportation
system—including both highways and rail—to
support the intermodal movement of goods
across the region
Consistent. Regional highway
connections to the Project site include
SR-241 and I-5. SR-241 is located
adjacent to the Project site and is
directly accessible from Alton Parkway.

Direct access to the Project site from I5 occurs from Towne Centre Drive via Bake Parkway and Portola Parkway via
Market Place. Therefore, the proposed
Project would be strategically located
to minimize miles traveled for delivery.

Source: Southern California Association of Governments, Connect SoCal – 2024-2050 Regional Transportation Plan/Sustainable Communities Strategy, April 2024.

Lake Forest 2040 General Plan
As discussed below and shown in Table 4-14, Project Consistency with the Lake Forest 2040 General Plan, in Section XI, Land Use and Planning, the proposed Project would not conflict with the City of Lake Forest 2040 General Plan. The Project is expected to serve the existing population of the area by providing more convenient access to Costco services. The Project site is located in a central location, and the proposed Project would allow customers to have multiple needs served in one trip, including but not limited to eye exams, purchase of household goods and groceries, and tire service. Additionally, the Project would be an infill development project located near existing commercial and residential developments, and would be located near existing transit facilities which would support numerous policies within the General Plan, as Item: 11
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demonstrated in Table 4-14. The Project would also include EV charging facilities, which would support Policy RR-4.9 by providing a convenient, low-cost EV charging station to members which would in turn replace conventionally fueled VMT with EV miles traveled, therefore reducing the GHG emissions of VMT in the region.

Based on the Project elements described above and the consistency analysis presented in Table 4-14, the Project would not interfere with the implementation of the Lake Forest General Plan and would include elements that support the goals of the plan.

Conclusion
As shown above, the Project would be consistent with the goals and policies of CARB’s 2022 Scoping Plan, SCAG’s Connect SoCal 2024, and the Lake Forest General Plan specific to reducing GHG emissions. The Project's GHG emissions do not exceed the SCAQMD Interim GHG Threshold and are in compliance with the reduction goals of the Lake Forest General Plan, AB 32, and SB 32. Furthermore, the Project would comply with applicable CALGreen standards and City of Lake Forest’s policies regarding sustainability as dictated by the 2040 General Plan. Impacts are less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR.

No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.

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IX. Hazards and Hazardous Materials
Would the project:

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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?
Construction activities associated with the proposed Project may involve the routine transport, use, or disposal of hazardous materials, such as petroleum-based fuels or hydraulic fluid used for construction equipment. The level of risk associated with the accidental release of hazardous substances is not considered significant due to the small volume and low concentration of hazardous materials utilized during construction. The construction contractor would be required to use standard construction controls and safety procedures that would avoid and minimize the potential for accidental release of such substances into the environment. Standard construction practices would be observed such that any materials released are appropriately contained and remediated as required by local, State, and federal law.

The Project includes commercial uses that would involve the use or storage of limited quantities of hazardous materials such as solvents, cleaners, pesticides, and other materials used for business operations, regular maintenance of buildings, and landscaping. Potentially hazardous materials may also be used, stored, and sold at the Costco warehouse and tire service center. Appropriate documentation for all hazardous materials, fuel, and other hazardous waste transported, sold, and stored in connection with operation of the Project would be provided as required for compliance with existing hazardous materials regulations. The quantities of these materials would not typically be at an amount that would pose a significant hazard to the public or the environment. Further, hazardous materials would be required to be stored, used, and disposed of in compliance with local, State, and federal regulations. The Project would be required to comply with additional regulatory requirements including, but not limited to, the Code of Federal Regulations, Title 49, Transportation, specific to the transport of hazardous materials; California Code of Regulations Titles 8, 22, and Title 26, and their enabling legislation set forth in California Health and Safety Code Division 20, Chapter 6.95, Hazardous Materials Release Response Plans and Inventory; and the requirements of the Certified Unified Program Agency, which would ensure safety standards related to the use and storage of hazardous materials are implemented. Adherence to existing regulations would ensure compliance with safety standards related to the use and storage of hazardous materials, and the safety procedures mandated by applicable federal, State, and local laws and regulations, which would ensure that risks resulting from the routine transportation, use, storage, or disposal of hazardous materials or hazardous wastes associated with implementation of the proposed Project would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. c) Emit hazardous emissions or handle hazardous or acutely hazardous materials, substances, or waste within one-quarter mile of an existing or proposed school? The Project site is located approximately 0.1-mile southeast of the Alpha School Lake Forest and Guidepost Montessori, both located at 26462 Towne Centre Drive. As discussed, construction activities associated with the proposed Project may involve the routine transport, use, or disposal of hazardous materials, such as petroleum-based fuels or hydraulic fluid used for construction equipment. The level of Item: 11
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risk associated with the accidental release of hazardous substances is not considered significant due to the small volume and low concentration of hazardous materials utilized during construction. The construction contractor would be required to use standard construction controls and safety procedures that would avoid and minimize the potential for accidental release of such substances into the environment. Standard construction practices would be observed such that any materials released are appropriately contained and remediated as required by local, State, and federal law. With respect to Project operation, the proposed commercial land uses are not associated with the types of uses that utilize large quantities of hazardous materials. While the proposed Costco warehouse and tire service center would involve the use or storage of limited quantities of hazardous materials, the use of these materials would be subject to federal, State, and local regulations. Any transport, storage, use, or disposal of hazardous materials would be subject to applicable State and federal laws, minimizing the potential for upset and accident conditions to occur within the site. Thus, impacts would be consistent with the less than significant impact determination of the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.
d) Be located on a site which is included on a list of hazardous materials sites compiled pursuant to Government Code Section 65962.5 and, as a result, would it create a significant hazard to the public or the environment?
Government Code Section 65962.5, commonly referred to as the “Cortese List,” requires the Department of Toxic Substances Control (DTSC) and the State Water Resources Control Board (SWRCB) to compile and update a regulatory sites list (pursuant to the criteria of the Section). The California Department of Health Services is also required to compile and update, as appropriate, a list of all public drinking water wells that contain detectable levels of organic contaminants and that are subject to water analysis pursuant to Health and Safety Code Section 116395. Government Code Section 65962.5 requires the local enforcement agency, as designated pursuant to Section 18051 of Title 14 of the California Code of Regulations, to compile, as appropriate, a list of all solid waste disposal facilities from which there is a known migration of hazardous waste.

The 2040 General Plan FEIR found that there are no hazardous materials release sites compiled pursuant to Government Code Section 65962.5 located in the 2040 General Plan Planning Area. Development allowed by the 2040 General Plan could create a hazard to the public or the environment through a disturbance or release of contaminated materials if the development occurs on or adjacent to contaminated sites without appropriate measures to contain or mitigate the existing contamination.

Federal and State regulations ensure that existing hazards, including those associated with known hazardous materials sites, are addressed prior to development. Additionally, before accepting as complete an application for any development project, the Local Guidelines for Implementing the California Environmental Quality Act Section states that the City shall consult lists compiled by the Secretary for Environmental Protection of the California EPA pursuant to Government Code Section 65962.5 listing hazardous waste sites and other specified sites located in the City’s boundaries. When acting as Lead Agency, the City shall notify an applicant for a development project if the project site is located on such a list and not already identified. The 2040 General Plan includes policies that are intended to ensure cleanup sites are identified, reviewed, and if needed, remediated, to prevent inappropriate release of hazardous materials. Additionally, as determined in the 2040 General Plan FEIR, compliance with Federal and State regulations and review requirements included in the City’s “Local Guidelines for Item: 11
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Implementing the California Environmental Quality Act” would ensure that potential impacts associated with the hazardous conditions on sites listed pursuant to Government Code Section 65962.5 would be less than significant.

A 2025 search of federal and State environmental databases comprising the Cortese list indicates that the Project site is not included on any of the data resources identified as meeting the Cortese List requirements.12,13,14 Therefore, the Project site has not been included on the list of hazardous materials sites compiled pursuant to the Government Code Section 65962.5, and it would not create a significant hazard to the public or environment. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. e) For a project located within an airport land use plan or, where such a plan has not been adopted, within two miles of a public airport or public use airport, would the project result in a safety hazard or excessive noise for people residing or working in the project area? The Project site in not located within an airport land use plan, nor is the Project site located within two miles of a public airport or public use airport. The closest airport to the Project site is John Wayne Airport, located approximately 11 miles to the west of the site. Thus, the Project would not result in a safety hazard or excessive noise for people residing or working in the Project area. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.
f) Impair implementation of or physically interfere with an adopted emergency response plan or emergency evacuation plan?
According to the 2040 General Plan, the City is a member of the Orange County Operational Area and the Orange County Emergency Management Organization. Both entities provide mutual aid to communities via the Orange County Sheriff's Department, Orange County Fire Authority, and the State of California Office of Emergency Services. The General Plan ensures that the City’s emergency access routes, emergency contact lists, and public information regarding designated facilities and routes are regularly reviewed to ensure that up to date information is available to the City and the public in the event of an emergency.

The Project site is located within Phase 4 of the Foothill Ranch Towne Centre, an established multi-tenant commercial center located along Towne Centre Drive. Bake Parkway and Alton Parkway provide access to Towne Centre Drive. Alton Parkway provides direct access to SR-241. Construction vehicles and 12 California Environmental Protection Agency, Cortese List Data Resources, https://calepa.ca.gov/sitecleanup/corteselist/, accessed December 14, 2025. 13 California Department of Toxic Substances Control, EnviroStor, https://www.envirostor.dtsc.ca.gov/public/map/?global_id=71002656, accessed December 14, 2025. 14 State Water Resources Control Board, GeoTracker, https://geotracker.waterboards.ca.gov/search, accessed December 14, 2025.

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equipment would be staged within the Project site. Construction activities are not anticipated to result in significant traffic or queuing along Towne Centre Drive or other roadways within the area that could potentially impede emergency vehicles or impair any emergency evacuation plan.

Similar to existing conditions, emergency vehicle access to the Project site would be provided via existing driveways along Towne Centre Drive and Market Place. These driveways connect to common driveways and drive aisles within the interior of the larger Phase 4 area. As part of the Project, the common driveway (i.e., Market Place) that extends from Towne Centre Drive between the Project site and the PetSmart building would be partially reconstructed. The existing four-way stop intersection located along the northern boundary of the Project site would be removed and a new three-way stop intersection would be constructed to the east. The existing driveway east of the former movie theater building would also be removed and reconstructed to the east of the proposed Costco Warehouse building. The proposed Project improvements would not involve physical modifications to Towne Centre Drive or other public roadways within the vicinity of the Project site. The proposed improvements within the Foothill Ranch Towne Centre would be required to comply with all applicable design requirements, including the CBC and California Fire Code, as adopted and amended by the City, and would be subject to approval by the City. As such, construction and operation of the proposed Project would not impair implementation of or physically interfere with an adopted emergency response plan or emergency evacuation plan. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.
g) Expose people or structures, either directly or indirectly, to a significant risk of loss, injury or death involving wildland fires?
The area surrounding the Project site is generally urbanized and developed with roadways and commercial uses. According to the California Department of Forestry and Fire Protection (CAL FIRE), the Project is located within a Local Responsibility Area (LRA) and is not identified as being within a Very High Fire Hazard Severity Zone (VHFHSZ).15 Thus, the Project site and surrounding area are not identified as having a significant risk associated with wildland fires. While the Project site is not located within a State Responsibility Area (SRA) or lands classified as VHFHSZ, a VHFHSZ within an LRA is located approximately

0.5 miles northwest of the site.

The Project proposes to demolish a former movie theater building and construct a new retail warehouse building with a tire service center. The proposed Project would be consistent with the General Plan land use and zoning for site and would not introduce new occupants or structures to a previously undeveloped site. Lake Forest Municipal Code Chapter 8.24, California Fire Code, adopts the California Fire Code, with amendments, which would further reduce potential impacts related to wildland fire. Compliance with Municipal Code, and State and federal regulations pertaining to fire safety, would ensure the Project does not expose people to a significant risk of loss, injury or death involving wildland fires. While the 2040 General Plan FEIR determined that program-level impacts related to implementation of the 2040 General 15 California Department of Forestry and Fire Protection, Find your Fire Hazard Severity Zone (FHSZ), https://osfm.fire.ca.gov/what-we-do/community-wildfire-preparedness-and-mitigation/fire-hazard-severity-zones, accessed December 14, 2025.

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Plan would be significant and unavoidable relative to this criterion, no project-level impacts would occur as a result of Project implementation. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.

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X. Hydrology and Water Quality
Would the project:

Significant
Impact
Peculiar to
the Project or
Project Site
Impact
Adequately
Addressed in
the General
Plan EIR
Impact
Substantially
Mitigated by
Uniformly
Applicable
Development
Standards
New
Potentially
Significant
Off-Site or
Cumulative
Impact not
Addressed in
the General
Plan EIR
Surface Water and Flooding
a. Substantially alter the existing drainage
pattern of the site or area, including
through the alteration of the course of a
stream or river, or substantially increase
the rate or amount of surface runoff in a
manner which would result in flooding onor offsite?
No Yes Yes No
b. Create or contribute runoff water which
would exceed the capacity of existing or
planned stormwater drainage systems?
No Yes Yes No
c. Place housing within a 100-year flood
hazard area as mapped on a federal Flood
Hazard Boundary or Flood Insurance Rate
Map or other flood hazard delineation
map?
No Yes No No
d. Place within a 100-year flood hazard area
structures which would impede or redirect
flood flows?
No Yes No No
e. Expose people or structures to a significant
risk of loss, injury or death involving
flooding, including flooding as a result of
the failure of a levee or dam?
No Yes No No
f. Cause inundation by a seiche, tsunami, or
mudflow? No Yes No No
g. Deposit sediment and debris materials
within existing channels obstructing flows? No Yes Yes No h. Exceed the capacity of a channel and cause
overflow during design storm conditions? No Yes Yes No
Groundwater
i. Substantially deplete groundwater
supplies or interfere substantially with
groundwater recharge such that there
would be a net deficit in aquifer volume or
a lowering of the local groundwater table
level (e.g. the production rate of preNo Yes No No
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existing nearby wells would drop to a level
which would not support existing land uses
or planned uses for which permits have
been granted)?
j. Adversely change the rate, direction or flow
of groundwater? No Yes No No
k. Have an impact on groundwater that is
inconsistent with a groundwater
management plan prepared by the water
agencies with the responsibility for
groundwater management?
No Yes No No
Water Quality
l. Violate any water quality standards or
waste discharge requirements? No Yes Yes No
m. Cause a significant alteration of receiving
water quality during or following
construction?
No Yes Yes No
n. Substantially degrade groundwater
quality? No Yes No No
o. Substantially alter the existing drainage
pattern of the site or area, including
through the alteration of the course of a
stream or river, in a manner which would
result in substantial erosion or siltation onor off-site? No Yes Yes No
p. Create or contribute runoff water which
would generate substantial additional
sources of polluted runoff?
No Yes Yes No
q. Substantially degrade water quality by
discharge which affects the beneficial uses
(i.e., swimming, fishing, etc.) of the
receiving or downstream waters?
No Yes Yes No
r. Increase in any pollutant for which the
receiving water body is already impaired as
listed on the Clean Water Act Section
303(d) list.

No Yes Yes No
This section is based in part on the Preliminary Hydrology & Hydraulics Report for SDP 05-25-5800 Costco Foothill Ranch (Hydrology Report), prepared by Kimley-Horn and Associates, Inc., dated November 2025 and included in its entirety as Appendix F, Hydrology Report; and the Santa Ana Region Priority Project Preliminary Water Quality Management Plan (PWQMP), Costco Foothill Ranch 26602 Towne Centre Drive, Foothill Ranch, CA (WQMP), prepared by Kimley-Horn and Associates, Inc., dated May 18, 2025 (Revised November 3, 2025) and included in its entirety as Appendix G, WQMP.

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Discussion: The 2040 General Plan FEIR determined that impacts to hydrology and water quality would be less than significant through the implementation of policies and actions in the 2040 General Plan.

SURFACE WATER AND FLOODING
a) Substantially alter the existing drainage pattern of the site or area, including through the alteration of the course of a stream or river, or substantially increase the rate or amount of surface runoff in a manner which would result in flooding on- or offsite? b) Create or contribute runoff water which would exceed the capacity of existing or planned stormwater drainage systems?
The Project site is currently developed with a commercial building, paved parking areas, and landscaping.

The site consists of approximately 94 percent impervious and six percent pervious surfaces. Under existing conditions, the Project site sheet flows in a southerly direction, where flows are captured by on-site catch basins. All runoff is captured into the existing underground storm drain system where it ultimately drains to Serrano Creek.

The Project would reduce the total impervious area from 94 percent in the existing condition to 93 percent in the proposed condition. Under proposed conditions, the site would continue to drain in a southerly direction. Stormwater flows would be captured by inlets and conveyed into a biofiltration BMP. Treated flows would be conveyed into a proposed underground detention system, which has been designed to meet water quality requirements and reduce peak flow. The detention basin’s outlet would restrict peak flows under proposed conditions to a level equal to or less than the existing flows. Overflow from the basin would discharge into the existing onsite storm drain system, which outfalls to Serrano Creek.

According to the Hydrology Report, the proposed on-site storm drain system would discharge less stormwater than existing conditions and is not expected to cause a negative impact to the downstream systems. Thus, the Project would not substantially alter the existing drainage pattern of the site or the area or substantially increase the rate or amount of surface runoff from the site. Further, the Project would not create or contribute runoff water which would exceed the capacity of existing or planned stormwater drainage systems. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. c) Place housing within a 100-year flood hazard area as mapped on a federal Flood Hazard Boundary or Flood Insurance Rate Map or other flood hazard delineation map? d) Place within a 100-year flood hazard area structures which would impede or redirect flood flows?
The Project site is not located within a 100-year Federal Emergency Management Agency (FEMA) flood zone.16 The Project does not propose any housing and would not place any structures within a 100-year flood zone. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. 16 Federal Emergency Management Agency, Flood Insurance Rate Map, Map Number 06059C0316J, December 3, 2009.

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Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. e) Expose people or structures to a significant risk of loss, injury or death involving flooding, including flooding as a result of the failure of a levee or dam? As previously discussed, the Project site is not located within a 100-year FEMA flood zone. In addition, the Project site is not within a mapped dam inundation area.17 The Project proposes an on-site storm drainage system which would be appropriately sized to reduce the risk of onsite flooding. According to the Hydrology Report, the proposed on-site storm drain system has been designed to restrict peak flows under proposed conditions to a level equal to or less than the existing flows. As such, the Project would not expose people or structures to a significant risk of loss, injury or death involving flooding, including flooding as a result of the failure of a levee or dam. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.
f) Cause inundation by a seiche, tsunami, or mudflow?
The Project site is approximately 11.5 miles inland of the Pacific Ocean and there are no large bodies of standing water near the Project site. As a result, tsunamis and seiches do not pose hazards due to the Project site’s inland location and lack of nearby bodies of standing water. The Project site and larger Foothill Ranch Towne Centre are relatively flat; there are no significant hillsides or landforms that would result in inundation associated with mudflow. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. g) Deposit sediment and debris materials within existing channels obstructing flows? Soil disturbance would temporarily occur during Project construction due to grading activities. Disturbed soils would be susceptible to increased rates of erosion from wind and rain, resulting in sediment transport via stormwater runoff from the Project site. The Project would be subject to compliance with the requirements set forth in Lake Forest Municipal Code Chapter 8.30, Grading and Excavation, and Chapter 15.14, Stormwater Quality Management, which include conditions and requirements related to erosion control and the reduction or elimination of storm water runoff pollutants during construction and operation. These regulations would require the Project contractor to include BMPs to ensure that the discharge of pollutants from the site would be effectively prohibited and would not cause or contribute to an exceedance of water quality standards or alter water quality during construction. Compliance with the Municipal Code would reduce the volume of sediment-laden runoff discharging from the site during construction activities.
17 California Department of Water Resources, Division of Safety of Dams, Dam Breach Inundation Map Web Publisher, https://fmds.water.ca.gov/webgis/?appid=dam_prototype_v2, accessed December 18, 2025.

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Given the nature of proposed use and the urbanized Project setting, long-term operation of the Project would not have the potential to result in a substantial increase in erosion or siltation offsite. The Project does not include large areas of exposed soils that would be subject to runoff; rather, any unpaved areas would retain existing landscaping and or areas would be improved with groundcover and landscaping to minimize the potential for erosion/siltation. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. h) Exceed the capacity of a channel and cause overflow during design storm conditions? As demonstrated above, the proposed Project would reduce the impervious surface area compared to existing conditions. In addition, the Project proposes an onsite storm drain system, which includes an underground detention system that has been designed to meet water quality requirements and reduce peak flows. As discussed in the Hydrology Report, the detention basin’s outlet would restrict peak flows under proposed conditions to a level equal to or less than the existing flows. Therefore, runoff from the Project would not exceed the capacity of the downstream storm drain system. Potential impacts related to exceedance of the capacity of a channel (or storm drain) or channel overflow during design storm conditions would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.

GROUNDWATER
i) Substantially deplete groundwater supplies or interfere substantially with groundwater recharge such that there would be a net deficit in aquifer volume or a lowering of the local groundwater table level (e.g. the production rate of pre-existing nearby wells would drop to a level which would not support existing land uses or planned uses for which permits have been granted)?
j) Adversely change the rate, direction or flow of groundwater? k) Have an impact on groundwater that is inconsistent with a groundwater management plan prepared by the water agencies with the responsibility for groundwater management? Irvine Ranch Water District (IRWD) provides water to the Project site. According to IRWD’s 2020 Urban Water Management Plan (UWMP), IRWD receives its water supplies from a mix of purchased imported water, surface water, groundwater and recycled water.18 Approximately 50 percent of IRWD’s overall supply comes from local groundwater wells in the Orange County Groundwater Basin and the Irvine and Lake Forest Sub-basins. IRWD is an operator of groundwater-producing facilities in the main portion of the Orange County Groundwater Basin and the Sub-basins.

The Orange County Water District (OCWD) serves as the groundwater manager over the Orange County Groundwater Basin and sub-basins. The majority of the groundwater rights of the producers within the 18 Irvine Ranch Water District, 2020 Urban Water Management Plan, June 2021.

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Basin have not been adjudicated, although IRWD holds an adjudicated right to the use of up to 4,500 AF of groundwater from the Basin. In 2014, the California Sustainable Groundwater Management Act (SGMA) was passed to help manage groundwater sustainably, and limit adverse effects such as significant groundwater-level declines, land subsidence, and water quality degradation. SGMA requires all high- and medium-priority basins, as designated by the Department of Water Resources (DWR), be sustainably managed. DWR designated the non-adjudicated Coastal Plain of OC Basin (Basin 8-1) as a medium-priority basin, primarily due to heavy reliance on the Basin’s groundwater as a source of water supply. The agencies within Basin 8-1 collaborated to prepare and submit an Alternative to a Groundwater Sustainability Plan on December 22, 2016.
19 On July 17, 2019, DWR determined that the Alternative satisfied SGMA objectives and was therefore approved. Approved alternatives are required to submit annual reports to DWR on April 1 of each year, and to resubmit the alternative by January 1 every five years. The 2022 Update to the Alternative, prepared to satisfy Water Code § 10733.8 and submitted in 2020, shows that the OCWD management area continues to be managed sustainably.

The Project proposes to demolish a former movie theater building and construct a new retail warehouse building with a tire service center. Employment-generating uses have recently occurred within the site and have been anticipated by 2040 General Plan. Further, the forecast population growth associated with the Project represents an increase of less than one percent (approximately 0.95 percent) in population over existing conditions and is within the growth projections anticipated by the 2040 General Plan; refer to Section XIV, Population and Housing. Due to the nature of the proposed use (retail warehouse and tire service center) and the relatively small number of new employees, the Project would not require a significant increase in water demand beyond land uses anticipated for the site. Further, IRWD’s 2020 UWMP indicates adequate water supplies would be available to serve future water demands during normal, dry, and multiple dry years through 2040, which includes water demand associated with commercial use of the site. Thus, Project implementation would not substantially decrease groundwater supplies.

Under existing conditions, the Project site is almost entirely paved and does not currently provide for significant groundwater recharge. According to the Preliminary WQMP, the Project’s percolation testing results from the Geotechnical Study state that infiltration is infeasible. As the Project site does not currently allow for infiltration and groundwater recharge, the Project would not interfere substantially with groundwater recharge such that there would be a net deficit in aquifer volume or a lowering of the local groundwater table; adversely change the rate, direction or flow of groundwater; or have an impact on groundwater that is inconsistent with a groundwater management plan. Impacts to groundwater would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.
19 Orange County Water District (OCWD), Basin 8-1 Alternative 2022 Update, January 2022.

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WATER QUALITY
l) Violate any water quality standards or waste discharge requirements? m) Cause a significant alteration of receiving water quality during or following construction? p) Create or contribute runoff water which would generate substantial additional sources of polluted runoff?
q) Substantially degrade water quality by discharge which affects the beneficial uses (i.e., swimming, fishing, etc.) of the receiving or downstream waters? r) Increase in any pollutant for which the receiving water body is already impaired as listed on the Clean Water Act Section 303(d) list.

Section 303(d) of the Clean Water Act (CWA) requires states to identify and list water bodies that do not meet, or are not expected to meet, water quality standards (i.e., “impaired” water bodies). The SWRCB’s Integrated Report includes the 303(d) listings for various water bodies within the Santa Ana RWQCB region and throughout the State. The 303(d) category lists the potential impairments associated with the constituents of concern (pollutants) for a particular water body. A Total Maximum Daily Loads (TMDL) is an estimate of the daily load of pollutants that a water body may receive from point sources, non-point sources, and natural background conditions (including an appropriate margin of safety), without exceeding its water quality standard. The purpose of TMDLs is to ensure that beneficial uses are restored and that water quality objectives are achieved. Those facilities and activities that are discharging into the water body, collectively, must not exceed the 303(d)-listed impairment and TMDL.

The Project site discharges to Serrano Creek, whose receiving waters include San Diego Reach 2, San Diego Reach 1, Newport Bay Upper, and Newport Bay Lower. Serrano Creek is listed as impaired from the following pollutants: ammonia (Unionized), toxicity, pH, indicator bacteria, and benthic community effects.
20 San Diego Reach 2 is listed as impaired from the following pollutants: benthic community effects, indicator bacteria, nutrients, sedimentation/siltation, and toxicity. San Diego Reach 1 is listed as impaired from the following pollutants: benthic community effects, DDT (dichlorodiphenyltrichloroethane), indicator bacteria, malathion, nutrients, sedimentation/siltation, selenium, toxaphene, and toxicity.

Newport Bay Upper is listed as impaired from the following pollutants: Chlordane, copper, DDT (Dichlorodiphenyltrichloroethane), indicator bacteria, malathion, nutrients, PCBs (polychlorinated biphenyl), sedimentation/siltation, and toxicity. Newport Bay Lower is listed as impaired from the following pollutants: chlordane, copper, DDT (Dichlorodiphenyltrichloroethane), indicator bacteria, nutrients, PCBs (polychlorinated biphenyl), and toxicity.

Short-Term Construction
The grading and site preparation required for Project implementation would result in exposed soils that may be subject to wind and water erosion. Construction-related erosion effects would be addressed 20 State Water Quality Control Board, 2024 Integrated Report, https://gispublic.waterboards.ca.gov/portal/apps/webappviewer/index.html?id=f0e4ac76fd0e4a53bebead89339e f3c9, accessed December 19, 2025.

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through compliance with the regulatory requirements of the Orange County Stormwater Program for North and Central Orange County and the NPDES General Permit for Stormwater Discharges Associated With Construction and Land Disturbance Activities (General Permit). Construction activity subject to the General Permit includes any construction or demolition activity, including, but not limited to, clearing, grading, grubbing, or excavation, or any other activity that results in a land disturbance of equal to or greater than one acre. The Project would disturb more than one acre and therefore would be subject to the General Permit. To obtain coverage under the General Permit, dischargers are required to file Permit Registration Documents with the SWRCB, which include a Notice of Intent and other compliance-related documents. The General Permit requires development and implementation of a SWPPP and monitoring plan, which must include erosion-control and sediment-control BMPs that would meet or exceed measures required by the General Permit to control potential construction-related pollutants. Erosioncontrol BMPs are designed to prevent erosion, whereas sediment controls are designed to trap sediment once it has been mobilized.

Construction activities would also be required to comply with water quality measures included in Lake Forest Municipal Code Chapter 8.30, Grading and Excavation, and Chapter 15.14, Stormwater Quality Management. These regulations would require the Project contractor to include BMPs to ensure that the discharge of pollutants from the site would be effectively prohibited and would not cause or contribute to an exceedance of water quality standards or alter water quality during construction. In accordance with Lake Forest Municipal Code Section 15.14.040, Control of Urban Runoff from New Development and Significant Redevelopment, prior to the issuance of grading permits, the Department of Public Works and/or Community Development would be required to review the Project plans and impose terms, conditions and requirements of the Project in accordance with the best management practices for pollution prevention, the City’s NPDES permit for discharges into and from its municipal separate storm sewer system (MS4), the Orange County Drainage Area Management Plan (DAMP), and any other conditions, requirements and water quality management plans adopted by the City. Thus, through adherence to the NPDES’s General Permit Program and City of Lake Forest Municipal Code regulations, water quality impacts associated with Project construction activities would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.

Long-Term Operations
The City manages local storm drain facilities and the Orange County Flood Control District (OCFCD) is responsible for regional flood control planning within the County. Provision of stormwater detention facilities as needed would reduce runoff rates and peak flows. The implementation of the 2040 General Plan includes policies aimed to enhance stormwater quality and infiltration as well as actions to review development projects to identify potential stormwater and drainage impacts and require development to include measures to ensure off-site runoff is not increased beyond pre-development levels. Existing regulatory requirements that manage water quality include requirements to obtain approval from the RWQCB for NPDES permits, other discharge permits, WQMPs, SWPPPs, and to implement BMPs. These regulatory requirements are intended to ensure that water quality does not degrade to levels that would violate water quality standards.

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The Project site is located within the jurisdiction of the Santa Ana Regional Water Quality Control Board (RWQCB) and would be subject to compliance with the NPDES Phase I MS4 permit. Under the Countywide MS4 permit issued by the Santa Ana RWQCB (Waste Discharge Requirements for the County of Orange, Orange County Flood Control District and Incorporated Cities of Orange County within the Santa Ana Region Areawide Urban Storm Water Runoff, Order No. R8-2009-0030, as amended), co-permittees, including the City of Lake Forest, must prepare a WQMP and implement BMPs, where feasible, to capture and treat stormwater prior to discharge to their MS4 facilities. Prior to building permit issuance, the Applicant would be required to submit a Final WQMP to the City for review and compliance with the County’s NPDES stormwater permit. The Final WQMP would be required to incorporate specific BMPs into the final Project design to address pollutants of concern associated with runoff from the Project site.

A Preliminary WQMP has been prepared for the Project to comply with the requirements of the Orange County Stormwater Program. The Preliminary WQMP identifies pollutants of concern associated with proposed Project, including suspended-solid/sediment, nutrients, heavy metals, pathogens (bacteria/virus), pesticides, oil and grease, toxic organic compounds, and trash and debris. Additionally, the Preliminary WQMP documents the various BMPs that would be implemented as part of the Project, which include site design, hydrologic source controls, biotreatment, hydromodification, treatment control, non-structural source control, and structural source control BMPs to address water quality conditions associated with the proposed Project. Proposed hydrologic source control BMPs include impervious area dispersion; proposed biotreatment BMPs include proprietary vegetated biotreatment systems; proposed hydromodification and treatment control BMPs include an EcoStream systems for treatment of runoff, proposed non-structural control BMPs include education, activity restrictions, common area landscape management, BMP maintenance, uniform fire code implementation, common area litter control, employee training, housekeeping of loading docks, common area catch basin inspection, and street sweeping; and structural source control BMPs include storm drain stenciling and signage, trash and waste storage design, efficient irrigation systems and landscape design, dock areas, requirements applicable to individual priority project categories, and wash water control for food preparation areas; refer to Appendix G for a detailed list of proposed BMPs.

Under proposed conditions, the site would continue to drain in a southerly direction. Stormwater flows would be captured by inlets and conveyed into a biofiltration BMP. Treated flows would be conveyed into a proposed underground detention system and overflow would discharge into the existing onsite storm drain system, which outfalls to Serrano Creek. Implementation of the proposed on-site stormwater system and Final WQMP, including water quality operational BMPs, would reduce pollutants of concern associated with the stormwater runoff from the Project site in compliance with the County’s MS4 Permit and ensure the proposed Project would not violate any water quality standards or waste discharge requirements; cause a significant alteration of receiving water quality; create or contribute runoff water which would generate substantial additional sources of polluted runoff; substantially degrade water quality by discharge which affects the beneficial uses of receiving downstream waters; or increase any pollutant for which the receiving water body is already impaired. Overall, the Project would reduce impervious surfaces when compared to existing conditions and would improve the quality of stormflows through the proposed on-site biotreatment system. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified.

Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.

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XI. Land Use and Planning
Would the project:

The Project proposes to demolish a former movie theater building and construct a new retail warehouse building with a tire service center. The Project proposes improvements to the common driveway (i.e., Market Place) and drive aisles within the interior of the larger Phase 4 area; however, these improvements would not involve any new roadways or significant infrastructure systems that would physically divide the site or separate the site from surrounding uses. Development of the site, as proposed, would be consistent with other land uses that occur within the surrounding area and would be consistent with the current General Plan land use designation and zoning for the site. Thus, the Project would not physically divide an Item: 11
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established community; impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR.

No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. b) Substantially conflict with existing on-site or adjacent land use due to project-related significant unavoidable indirect effects (e.g., noise, aesthetics, etc.) that preclude use of the land as it was intended by the General Plan?
The Project site is designated Mixed-Use 43 (MU-43). The Mixed-Use 43 designation provides opportunities for mixtures of commercial, office, and residential uses in the same building, on the same parcel of land, or within the same area. This designation allows for vertical integration of compatible uses, whereby such uses share the same building or lot, or horizontal integration of uses, where compatible uses are located next to each other. Single-use projects are allowed; stand-alone residential projects should be located in proximity to nonresidential development. The maximum intensity of development is a floor area ratio of 1.2:1.

The Project proposes to demolish a former movie theater building and construct a new retail warehouse building with a tire service center. The proposed Project would not substantially conflict with existing onsite or adjacent land uses, as the Project would result in a continuation of commercial uses within the site.

The proposed uses would be consistent with the General Plan and zoning for the site and would not require a General Plan amendment or zone change. Further, as discussed throughout this Environmental Compliance Checklist, the proposed use would not result in significant unavoidable indirect effects that would impact an existing on-site or adjacent land use precluding use of the land as it was intended by the General Plan. Thus, less than significant impacts would occur in this regard, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. c) Conflict with any applicable land use plan, policy, or regulation of an agency with jurisdiction over the project (including, but not limited to the general plan, planned community, or zoning ordinance) adopted for the purpose of avoiding or mitigating an environmental effect? The Project site is designated Mixed-Use 43 (MU-43). The Mixed-Use 43 designation provides opportunities for mixtures of commercial, office, and residential uses in the same building, on the same parcel of land, or within the same area. Single-use projects are allowed; stand-alone residential projects should be located in proximity to nonresidential development. The proposed Project would be an allowed use per the 2040 General Plan land use designation and no amendments to the General Plan would be required. Thus, the proposed Project would not conflict with the 2040 General Plan.

The Project site is zoned Mixed-Use 43 (MU-43) in the Foothill Ranch Planned Community. The MU-43 district provides for mixtures of commercial, office, and residential uses in the same building, on the same parcel of land or within the same area. Single-use projects, such as projects that are all residential, or all commercial are allowed. Land Use regulations for the MU-43 zoning district are subject to the regulations in Lake Forest Municipal Code Section 9.73.065, Mixed-use Land Use Matrix, Column MU 43. Retail businesses are permitted uses by right; light auto repair uses are permitted with approval of a Use Permit.

Use Permit (UP 05-25-5802) for light auto repair in the tire center. Thus, with approval of UP 05-25-5802, the Project would be consistent with the zoning for the site and impacts would be less than significant.

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The Project would be required to comply with the relevant development standards and design guidelines, such as those established in the City’s Municipal Code, Citywide Design Guidelines, and the Foothill Ranch Planned Community Development Plan and Supplemental Text. The Project requires approval of a Site Development Permit (Municipal Code Chapter 9.184, Discretionary Permits), which would allow for discretionary review of the Project. The decision-making authority would be required to make findings for approval including consistency with the General Plan, consistency with the Zoning Code, compliance with CEQA, compatibility with surrounding development, and consistency with the Citywide Design Guidelines.

Further, the Project requires approval of a Use Permit to allow for alcoholic beverage sale for off-site consumption, for light auto repair in the tire center, and for exceptions to the mixed-use development regulations. In accordance with Lake Forest Municipal Code Chapter 9.184, Discretionary Permits, a Use Permit provides for public review of detailed final plans for a proposed use. A Use Permit is a precise plan of development and is required to include a description of the use(s) and operating characteristics; a plot plan showing the location of all uses; supplementary exhibits, as necessary, to show other information which may be required such as building elevations, landscaping, and grading; and conditions of approval.

Processing of a Use Permit would require a public hearing. Thus, with approval of the Site Development Permit (SDP 05-25-5800) and Use Permits and Public Convenience and Necessity (UP 05-25-5801 and PCN 12-25-5850 for alcoholic beverage sale for off-site consumption; UP 05-25-5802 for light auto repair in the tire center; and UP 05-25-5803 for exceptions to the mixed-use development regulations), the Project would be consistent with the site development standards of the MU-43 zone and impacts would be less than significant.

An analysis of the proposed Project’s consistency with relevant policies of the 2040 General Plan adopted for the purpose of avoiding or mitigating an environmental effect, is provided in Table 4-14, Project Consistency with the Lake Forest 2040 General Plan. As indicated in Table 4-14, the Project would not conflict with any General Plan policies adopted for the purpose of avoiding or mitigating an environmental effect.

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Table 4-14
Project Consistency with the Lake Forest 2040 General Plan # Policy Consistency Analysis
Land Use and Design Element
LU-1.8 Consistent Standards. Require projects to
adhere to the City’s Municipal Code.

Consistent. As demonstrated in the discussion
above, the Project would be consistent with the
zoning for the Project site and would adhere to the
City’s development standards for the MU-43 zoning
district. The Project requires approval of a Site
Development Permit, which would allow for
discretionary review of the Project. The decisionmaking authority would be required to make findings for approval including, but not limited to, consistency with the Zoning Code.

LU-2.5 Visual Compatibility. Require new
development projects achieve visual
compatibility with surrounding development
through building, site, or design techniques,
such as landscaping and architectural design,
to achieve visual compatibility.

Consistent. As demonstrated in Section I, Aesthetics,
the Project would be visually compatible with
surrounding development. Further, the Project
requires approval of a Site Development Permit,
which would allow for discretionary review of the
Project. The decision-making authority would be
required to make findings for approval including
consistency with the General Plan, consistency with
the Zoning Code, compliance with CEQA,
compatibility with surrounding development, and
consistency with the Citywide Design Guidelines.

LU-2.11 Federal Aviation Administration Imposed
Height Restrictions. Require projects 200 feet
above ground level to file with the Federal
Aviation Administration (FAA) Form 7460-1
Notice of Proposed Construction and
Alteration and provide notification to the
ALUC; note that the City of Lake Forest
prohibits development at this height but
should projects at this height be considered at
some point in the future, this policy shall
apply.

Consistent. The Project proposes a building height of
34 feet, which is less than the 200 feet notification
threshold.

LU-4.4 Building Footprint. Require and enforce
appropriate residential and nonresidential
development standards, including adequate
building setbacks, to ensure that a building’s
footprint does not negatively affect adjacent
uses or the visual quality of the area.

Consistent. Refer to response to Policies LU-1.8 and
LU-2.5, above.

LU-5.6 Design Integration. Require that residential
and nonresidential portions of mixed-use
buildings and sites be integrated through site
and building design to ensure compatibility
among uses.

Consistent. While the Project is located within the
MU-43 zoning district, the Project proposes only
non-residential uses. Refer to response to Policy LU2.5.

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Table 4-14 (continued)
Project Consistency with the Lake Forest 2040 General Plan # Policy Consistency Analysis
Recreation and Resources Element
RR-2.3 Scenic Resources. Protect Lake Forest’s scenic
resources, including scenic corridors along
roads and views of the hillsides, prominent
ridgelines, canyons, and other significant
natural features, to the extent practical.

Consistent. As demonstrated in Section I, Aesthetics,
the Project would not substantially damage scenic
resources.

RR-3.1 Preservation. Protect areas containing
significant historic, archaeological, and
paleontologic resources, as defined by the
California Public Resources Code.

Consistent. As discussed in Section V, Cultural
Resources and Section VII, Geology and Soils, there
are no known historic, archaeological, and
paleontological resources within the Project site;
however, as with the rest of Lake Forest, there is the
potential for unknown or undiscovered cultural
resources to be uncovered through construction
activities. As a condition of approval, archaeological
awareness training for Project personnel conducting
ground disturbing activities would be required prior
to the start of work. Further, the Project would be
required to implement applicable 2040 General Plan
policies and actions, including Actions RR-3b and RR3d. Therefore, as demonstrated in Section V, Cultural Resources and Section VII, Geology and Soils, The
Project would not result in significant impacts to
historic, archaeological, or paleontological
resources.

RR-3.3 Development. Ensure that human remains are
treated with sensitivity and dignity, and
ensure compliance with the provisions of
California Health and Safety Code Section
7050.5 and California Public Resources Code
Section 5097.98.

Consistent. As discussed in Section V, Cultural
Resources, compliance with the established
regulatory framework (California Health and Safety
Code Section 7050.5, Public Resources Code Section
5097.98, and the California Code of Regulations
Section 15064.5(e)), including General Plan Action
RR-3b, which details the appropriate actions
required in the event human remains are
encountered, will ensure the Project’s potential
impacts concerning human remains would be less
than significant.

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Table 4-14 (continued)
Project Consistency with the Lake Forest 2040 General Plan # Policy Consistency Analysis
RR-4.2 Land Use Planning. Utilize land-use planning
techniques to reduce traffic congestion and
promote alternative modes of transportation
for the community.

Consistent. The Project site is located near the BakeTowne Centre bus stop and is within walking/biking distance of the nearest residences, as well as other
shops in the Foothill Ranch Towne Centre, therefore
promoting alternative modes of transportation
which would reduce peak-hour vehicle trips. The
Project site is located in a central location that is
within a 15-minute walk of the nearest residences
and would allow Project customers to have multiple
needs served in one trip, including but not limited to:
eye exams, purchase of household goods and
groceries, and tire service. The Project would provide
retail and jobs near a housing-rich area served by the
OCTA. Additionally, as shown in Table 4-31, the
Project is estimated to result in a net decrease of
4,737 miles to total regional daily VMT.

RR-4.3 Development. Encourage and incentivize the
development of mixed-use residential
opportunities and live-work environments
within the City to lessen the impacts of traffic
congestion on local air quality.

RR-4.8 Local Reduction Targets. The City of Lake
Forest establishes the following per capita
GHG reduction targets, in order to meet the
requirements established by the state under
AB 32 and SB 32, consistent with the CARB’s
2017 Scoping Plan:
• 3.99 MT CO2e per capita by 2030
• 2.66 MT CO2e per capita by 2040; and
• 1.33 MT CO2e per capita by 2050
Consistent. This is a City-wide target and it is not
applicable to an individual project. Nonetheless, as
demonstrated in Section VIII, Greenhouse Gas
Emissions, the Project would have a less than
significant GHG impact.

RR-4.9 GHG Reduction. Consider and adopt new
policies and programs that will help to provide
energy efficient alternatives to fossil fuel use
and reduce consumption in order to reduce
greenhouse gas emissions.

Consistent. This is a policy that the City would
implement rather than an individual project.

However, the Project would include a number of
energy saving requirements, which would lead to
GHG reduction as well, which are described in detail
above. Further, the Project would include solar
panels which would provide renewable energy to the
Project and further reduce the GHG emissions
associated with the building energy.

RR-4.10 Carbon Reduction. Expand the number of
parks and trees in Lake Forest to provide a
larger carbon sink or area containing natural
sources that retain more carbon than what
those sources emit.

Consistent. This is a policy that the City would
implement rather than an individual project.

However, the Project would include a greater
amount of landscaped area when compared to
existing conditions. Proposed landscaping includes
groundcover, bushes, and trees.

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Table 4-14 (continued)
Project Consistency with the Lake Forest 2040 General Plan # Policy Consistency Analysis
RR-5.3 Sensitive Communities. Protect and conserve
Lake Forest’s biological resources, with a
special focus on sensitive, rare, or endangered
plant and wildlife species in accordance with
state and federal resource agency
requirements.

Consistent. As discussed in Section IV, Biological
Resources, as the Project site is currently developed
and disturbed, it is generally not suitable for any
special status species, is devoid of sensitive habitat, and does not contain wetlands or wetland habitat.

However, the Project site contains some trees,
shrubs, and other vegetation that could provide
potential nesting habitat for common birds, including
birds and raptors protected under the MBTA and
CFG. Project construction activities would be
required to comply with applicable State and federal
requirements, including the provisions of the MBTA
and Sections 3503, 3503.5, 3513 of the CFG, which
protect active nests of avian species. As such, the
Project would be consistent with this policy.

RR-5.7 Development. Require that all new
development identify potential impacts to
existing biological resources and provide
mitigation measures as necessary pursuant to
CEQA in order to protect these resources from
negative externalities.

Consistent. Refer to response to Policy RR-5.3.

RR-6.1 Compliance with State Legislation. Continue
to comply with all State regulations regarding
waste diversion, source reduction, recycling,
and composting, and strive to achieve an 85%
diversion rate from landfills by 2040.

Consistent. As discussed in Section XIX, Utilities and
Service Systems, the Project would be required to
comply with State requirements related to solid
waste. For example, Project construction would be
required to comply with CALGreen and the Lake
Forest Municipal Code Chapter 16.12, Construction
and Demolition Debris Diversion, which promotes the
recycling of construction and demolition debris to
meet the City’s obligations under AB 939. Projects
are required to reuse, recycle, salvage, or divert a
minimum percentage or amount of construction and
demolition debris in accordance with the
requirements of CALGreen. Project operation would
also be required to comply with Chapter 16.14,
Mandatory Organic Waste Disposal, which addresses
organic waste disposal consistent with the Shortlived Climate Pollutant Reduction Act (SB 1383).

RR-6.2 Compliance with Regional Plans. Reduce the
per capita generation of solid waste in Lake
Forest in concert with the County of Orange
source reduction and recycling plans for
reducing solid waste.

Consistent. The Project would be required to reduce
solid waste in compliance with State and regional
solid waste and recycling plans; refer to response to
Policy RR-6.1.

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Table 4-14 (continued)
Project Consistency with the Lake Forest 2040 General Plan # Policy Consistency Analysis
Public Safety Element
PS-1.2 Earthquake Protection. Enforce State seismic
design guidelines and all relevant building
codes to reduce the risk of damage associated
with seismic activity.

Consistent. As discussed in Section VII, Geology and
Soils, the Project would be required to comply with
the seismic design standards of the CBC.

PS-1.3 Liquefaction. Require special site-specific
studies in areas potentially subject to
liquefaction (shown in Figure 9-5 of the
General Plan Existing Conditions Report) to
determine the nature and extent of possible
liquefaction and to identify engineering and
development siting measures to permit
development to occur.

Consistent. As discussed in Section VII, Geology and
Soils, the Project site is not located within a State
hazard zone for liquefaction. Because of the lack of
groundwater and the soil types at the site, the
Geotechnical Study concludes that the potential for
liquefaction is not considered a hazard at the site.

PS-1.4 Development. Require assessment and
mitigation of hazards related to liquefaction,
landslides, and flooding for new development
projects or City improvement projects that are
identified by the City as susceptible to these
hazards.

Consistent. As discussed in Section VII, Geology and
Soils and Section X, Hydrology and Water Quality, the
Project would result in less than significant impacts
related to liquefaction, landslides, and flooding.

PS-2.1 Building Fire Codes. Require that all buildings
and facilities within Lake Forest comply with
local, state, and federal regulatory standards
such as the California Building and Fire Codes
as well as other applicable fire safety
standards.

Consistent. As discussed in Section IX, Hazards and
Hazardous Materials, the Project would be required
to comply with the CBC and California Fire Code, as
adopted and amended by the Lake Forest Municipal
Code.

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Table 4-14 (continued)
Project Consistency with the Lake Forest 2040 General Plan # Policy Consistency Analysis
PS-2.4 Very High Fire Hazard Severity Zones. Require
that all development in VHFHSZs meet the
following standards:
a. Minimize new residential
development in VHFHSZs when possible.
b. Coordinate with OCFA to ensure
adequate fire protection services, fire
protection plans, and emergency vehicle
access are provided for new development in
VHFHSZs.
c. As part of future a land use plan
updates or amendments, assess site
constraints when considering land use
designations near wildlands to avoid or
minimize wildfire hazards.
d. Coordinate with OCFA to identify
building and site design methods or other
methods to minimize damage if new
structures are proposed to be in VHFHSZs on
undeveloped land and when rebuilding after a
fire.
e. As part of the OCFA review process,
require ongoing brush management, fuel
management/modification, defensible space,
fire retardant landscaping, and other project
design features for new development located
in areas of or adjacent to high wildfire risk.
f. Coordinate with the applicable water
district to ensure necessary water supply
systems and flow for structural fire
suppression are provided and maintained.
g. Work with OCFA and local HOAs to
identify and maintain fire hazard reduction
projects, including community fire breaks and
private road and public road clearance.
h. Coordinate with OCFA to define
minimum standards for evacuation of
residential areas in VHFHSZs. If areas with
inadequate access/evacuation routes are
identified, develop appropriate mitigation
measures, improvement plans, or education
programs to ensure safe evacuation.

Consistent. As discussed in Section IX, Hazards and
Hazardous Materials, the Project site is not located
within a VHFHSZ.

PS-3.3 Municipal Code. Implement the standards and
requirements defined in the Municipal Code
to reduce flood hazards and address floodprone areas within Lake Forest.

Consistent. As discussed in Section X, Hydrology and
Water Quality, the Project site is not located within a 100-year FEMA flood hazard zone and would not
result in significant impacts related to flooding.

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Table 4-14 (continued)
Project Consistency with the Lake Forest 2040 General Plan # Policy Consistency Analysis
PS-3.6 Mitigation. Require that all new development
and redevelopment in areas susceptible to
flooding incorporate mitigation measures
designed to reduce flood hazards.

Consistent. Refer to response to Policy PS-3.3.

PS-4.2 Cleanup Sites. Require that developers
coordinate with the Orange County Health
Care Agency to confirm that hazardous waste
cleanup sites located within the City are
remediated by the property owner in a
manner that keeps the public safe.

Consistent. As discussed in Section IX, Hazards and
Hazardous Materials, the Project site is not located
on the Cortese list and would result in less than
significant impacts related to hazardous materials
sites.

PS-6.1 Land Use Planning. Require development and
infrastructure projects to be consistent with
the maximum allowable noise exposure
criteria identified in Table PS-1 to ensure
acceptable noise levels for future
development.

Consistent. As discussed in Section XIII, Noise, the
Project would be consistent with the City’s noise
exposure criteria and would not result in significant
noise impacts.

PS-6.3 Site Design. Require site planning and project
design techniques to minimize noise impacts
adjacent to sensitive uses in order to comply
with City standards.

Consistent. Refer to response to Policy PS-6.1.

PS-6.8 Commercial Noise. Require the use of noise
attenuation measures, including screening
and buffering techniques, for all new
commercial development expected to
produce excessive noise; in existing cases
where the City's noise standards are
exceeded, work with Code Enforcement to
require compliance.

Consistent. Refer to response to Policy PS-6.1.

Public Facilities
PF-1.4 Impact on Resources. Require new utility
infrastructure to avoid sensitive natural and
cultural resources to the greatest extent
feasible.

Consistent. Refer to responses to Policy RR-3.1 and
Policy RR-5.3.

PF-2.1 New Development. Require that new
development participates in the provision and
expansion of public services, recreational
amenities, and facilities.

Consistent. As demonstrated in Section XV, Public
Services and Section XVI, Recreation, the Project
would result in less than significant impacts related
to public services and facilities, including recreational amenities.

PF-2.2 Demonstrate Capacity. Request to
demonstrate that the City’s public services and
facilities can accommodate the increased
demand for said services and facilities
associated with the project as part of the
entitlement process.

Consistent. Refer to response to Policy PF-1.4.

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Table 4-14 (continued)
Project Consistency with the Lake Forest 2040 General Plan # Policy Consistency Analysis
PF-2.3 Mitigate Impacts. Require new development
to offset or mitigate impacts to community
services and facilities to ensure that service
levels for existing users are not degraded or
impaired by new development, to the
satisfaction of the City.

Consistent. Refer to response to Policy PF-1.4.

PF-3.6 Water Conservation. Support water
conservation measures that comply with state
and federal legislation and that are consistent
with measures adopted in all applicable Urban
Water Management Plans.

Consistent. The Project would comply with
CALGreen standards and includes water
conservation and water-efficient measures, as
discussed in Section VIII, Greenhouse Gas Emissions.

Source: City of Lake Forest, Lake Forest 2040 General Plan, June 2020.

As discussed, the Project would be consistent with the General Plan land use designation and would be consistent with the zoning for the Project site. Further, the Project would be consistent with the development standards for the MU-43 zone. As demonstrated in Table 4-14, the proposed Project would be consistent with applicable General Plan policies. Thus, the proposed Project would not cause a significant environmental impact due to a conflict with any land use plan, policy, or regulation adopted for the purpose of avoiding or mitigating an environmental effect. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.
d) Conflict with the Central and Coastal Natural Communities Conservation Program/Habitat Conservation Plan (NCCP/HCP) of which the City of Lake Forest is a participant? Impacts under this criterion are discussed in Section 4.3, Biological Resources, of the 2040 General Plan FEIR, which concluded that future projects that do not comply with the Orange County Central-Coastal NCCP/HCP could result in potentially significant impacts, which would be mitigated to a less than significant level through the implementation of 2040 General Plan Action RR-5b. 2040 General Plan Action RR-5b requires new development projects to comply with the requirements of the NCCP/HCP to ensure that potentially significant impacts to special-status species and sensitive resources are adequately addressed.

The Project site is currently developed and within an urbanized area and is not located within the boundaries of the NCCP/HCP reserve system. Therefore, the proposed Project would not conflict with the NCCP/HCP or other approved local, regional, or State habitat conservation plan. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.

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XII. Mineral Resources
Would the project:

However, the significance of the deposit is undetermined. • MRZ-3b: Areas where the available geologic information indicates that mineral deposits are likely to exist. However, the significance of the deposit is undetermined. • MRZ-4: Areas where there is not enough information available to determine the presence or absence of mineral deposits.

As stated in the 2040 General Plan FEIR, the Planning Area does not contain a locally-important mineral resource recovery site delineated on a local general plan, specific plan, or other land use plan. The Project site is currently developed with commercial uses and is not used for mineral resource recovery operations.

The Project site and surrounding area are not identified as MRZs and the Project would not result in the loss of availability of known mineral resources of value to the region or result in the loss of a locallyimportant mineral resource recovery site delineated on a local general plan, specific plan, or other land Item: 11
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use plan. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.

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XIII. Noise
Would the project:

No Yes No No
2) The resulting “future with project” noise
level exceeds the noise standard for
sensitive land uses as identified in the
City of Lake Forest General Plan (refer
to Table 3-1 in Section 3.3 Interior and
Exterior Noise Standards).

No Yes No No
b. Exceed the stationary noise criteria for the
City of Lake Forest as specified by the
exterior noise standards set forth in the
Noise Control Chapter of the Lake Forest
Municipal Code?
No Yes No No
c. Generation of excessive groundborne
vibration or groundborne noise levels? No Yes No No
d. For a project located within the vicinity of a
private airstrip or an airport land use plan
or, where such a plan has not been adopted,
within two miles of a public airport or
public use airport, would the project
expose people residing or working in the
project area to excessive noise levels?
No Yes No No
This section is based in part on the Environmental Noise Impact Study, Costco Wholesale Warehouse Project Foothill Ranch, California (Noise Impact Study), prepared by Acoustical Engineering Services, Inc., dated January 2026, and included in its entirety as Appendix H, Noise Impact Study.

Discussion: The 2040 General Plan FEIR determined that noise and vibration impacts would be less than significant through the implementation of policies and actions in the 2040 General Plan.

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FUNDAMENTALS OF SOUND AND ENVIRONMENTAL NOISE
Noise is commonly defined as sound that is undesirable because it can interfere with speech communication and hearing, may cause sleep disturbance, or may otherwise be considered annoying (unwanted sound). The decibel (dB) is a conventional unit for measuring the amplitude of sound because it accounts for the large variations in sound pressure amplitude and reflects the way people perceive changes in sound amplitude. The human hearing system is not equally sensitive to sound at all frequencies. Therefore, to approximate this human frequency-dependent response, the A-weighted filtering system is used to adjust measured sound levels (dBA). The term “A-weighted” refers to filtering the noise signal in a manner that corresponds to the way the human ear perceives sound.

Generally, people judge the relative magnitude of sound sensation by subjective terms such as “loudness” or “noisiness.” To the normal human ear, a change in sound level of 3 dB is considered “just perceptible,” a change in sound level of 5 dB is considered “clearly noticeable,” and a change (i.e., increase) of 10 dB is generally recognized as “twice as loud.

Environmental Noise Descriptors
Equivalent Sound Level (Leq). Leq is a measurement of the acoustic energy content of noise averaged over a specified period. Thus, the Leq of a time-varying sound and that of a steady sound are the same if they deliver the same amount of energy to the receptor’s ear during exposure. Leq for one-hour periods, during the daytime or nighttime hours, and 24 hours are commonly used in environmental noise assessments.

Leq can be measured for any period but is typically measured for an increment of no less than 15 minutes for environmental studies. For evaluating community impacts, this rating scale does not vary, regardless of whether the noise occurs during day or night.

Sound Exposure Level (SEL). SEL is used to evaluate noise effects from the operation of the helistop (i.e., helicopter flight noise) on noise sensitive land uses such as residential. SEL is an energy-based sum of the noise experienced during a single noise event, normalized to one second duration.

Community Noise Equivalent Level (CNEL). CNEL is the time average of all A-weighted sound levels for a 24-hour period with a 10 dBA adjustment (upward) added to the sound levels that occur between the hours of 10:00 p.m. and 7:00 a.m. (nighttime), and a 5 dBA adjustment (upward) added to the sound levels which occur between the hours of 7:00 p.m. and 10:00 p.m. (evening). These penalties attempt to account for increased human sensitivity to noise during the nighttime and evening periods, particularly where sleep is the most probable activity. CNEL has been adopted by the State of California to define the community noise environment for development of the community noise element of a General Plan.

Groundborne Vibration
Vibration is commonly defined as an oscillatory motion through a solid medium in which the motion’s amplitude can be described in terms of displacement, velocity, or acceleration. The peak particle velocity (PPV) or the root-mean square (RMS) velocity is usually used to describe vibration amplitudes. PPV is defined as the maximum instantaneous peak of the vibration signal and is typically used for evaluating potential building damage. The RMS velocity is defined as the square-root of the average of the squared amplitude of the vibration signal and is typically more suitable for evaluating human response to groundborne vibration. The RMS vibration velocity level can be presented in inch per second or in VdB (a decibel unit referenced to 1 micro-inch per second). Ground-borne vibration generated by man-made activities Item: 11
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(e.g., road traffic, construction operations) typically weakens with greater horizontal distance away from the source of the vibration.

REGULATORY FRAMEWORK
City of Lake Forest 2040 General Plan
The City’s General Plan Public Safety Element Tables PS-1 and PS-2 identifies the maximum allowable noise exposure standards to ensure acceptable noise levels for existing and future development and performance standards for stationary noise sources; refer to Table 4-15, Land Use Compatibility for Community Noise Environment and Table 4-16, Performance Standards for Stationary Noise Sources, Including Affected Projects.

Table 4-15
Land Use Compatibility for Community Noise Environment
Land Use Outdoor Activity
Areas2,3
Interior Spaces
Ldn/CNEL, dB Leq, dB4
Residential 60 45 --
Motels/Hotels 65 45 --
Mixed-Use 65 45 --
Hospitals, Nursing Homes 60 45 --
Theaters, Auditoriums -- -- 35
Churches 60 -- 40
Office Buildings 65 -- 45
Schools, Libraries, Museums 70 -- 45
Playgrounds, Neighborhood Parks 70 -- --
Industrial 75 -- 45
Golf Courses, Water Recreation 70 -- --
Source: City of Lake Forest General Plan 2040; Table PS-1 Notes:

1. Where a proposed use is not specifically listed, the use shall comply with the standards for the most similar use as determined by the City.

2. Outdoor activity areas for residential development are considered to be the backyard patios or decks of single-family units and the common areas where people generally congregate for multi-family developments. Where common outdoor activity areas for multi-family developments comply with the outdoor noise level standard, the standard will not be applied at patios or decks of individual units provided noise-reducing measures are incorporated (e.g., orientation of patio/deck, screening of patio with masonry or other noise-attenuating material). Outdoor activity areas for non-residential developments are the common areas where people generally congregate, including pedestrian plazas, seating areas, and outside lunch facilities; not all residential developments include outdoor activity areas.

3. In areas where it is not possible to reduce exterior noise levels to achieve the outdoor activity area standard using a practical application of the best noise-reduction technology, an increase of up to 5 Ldn over the standard will be allowed provided that available exterior noise reduction measures have been implemented and interior noise levels are in compliance with this table.

4. Determined for a typical worst-case hour during periods of use.

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Table 4-16
Performance Standards for Stationary Noise Sources, Including Affected Projects Noise Level Descriptor Daytime
7 am to 10 pm
Nighttime
10 pm to 7 am
Hourly Leq, dBA 55 50
Source: City of Lake Forest General Plan 2040; Table PS-12.

Notes:

1. Each of the noise levels specified above should be lowered by 5 dB for simple noise tones, noises consisting primarily of speech or music, or recurring impulsive noises. Such noises are generally considered to be particularly annoying and are a primary source of noise complaints.

2. No standards have been included for interior noise levels. Standard construction practices should, with the exterior noise levels identified, result in acceptable interior noise levels.

3. Stationary noise sources which are typically of concern include, but are not limited to, the following:

HVAC Systems Cooling Towers/Evaporative Condensers
Pump Stations Lift Stations
Emergency Generators Boilers
Steam Valves Steam Turbines
Generators Fans
Air Compressors Heavy Equipment
Conveyor Systems Transformers
Pile Drivers Grinders
Drill Rigs Gas or Diesel Motors
Welders Cutting Equipment
Outdoor Speakers Blowers

4. The types of uses which may typically produce the noise sources described above include but are not limited to:
industrial facilities, pump stations, trucking operations, tire shops, auto maintenance shops, metal fabricating shops, shopping centers, drive-up windows, car washes, loading docks, public works projects, batch plants, bottling and canning plants, recycling centers, electric generating stations, race tracks, landfills, sand and gravel operations, and athletic fields.

Action PS-6d states: In making a determination of impact under the California Environmental Quality Act (CEQA), a substantial increase will occur if ambient noise levels have a substantial increase. Generally, a 3 dB increase in noise levels is barely perceptible, and a 5 dB increase in noise levels is clearly perceptible.

Therefore, increases in noise levels shall be considered to be substantial when the following occurs:
● When existing noise levels are less than 60 dB, a 5 dB increase in noise will be considered substantial;
● When existing noise levels are between 60 dB and 65 dB, a 3 dB increase in noise will be considered substantial;
● When existing noise levels exceed 65 dB, a 1.5 dB increase in noise will be considered substantial.

Action PS-6e states: Update the City’s Noise Ordinance (Chapter 11.16) to reflect the noise standards established in this General Plan and proactively enforce the City’s Noise Ordinance, including requiring the following measures for construction:
● Restrict construction activities to the hours of 7:00 a.m. to 7:00 p.m. on Monday through Friday, and 8:00 a.m. to 6:00 p.m. on Saturdays. No construction shall be permitted outside of these hours or on Sundays or federal holidays, without a specific exemption issued by the City. ● A Construction Noise Management Plan shall be submitted by the Applicant for construction projects, when determined necessary by the City. The Construction Noise Management Plan shall Item: 11
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include proper posting of construction schedules, appointment of a noise disturbance coordinator, and methods for assisting in noise reduction measures. ● Noise reduction measures may include, but are not limited to, the following:
o Equipment and trucks used for project construction shall utilize the best available noise control techniques (e.g., improved mufflers, equipment redesign, use of intake silencers, ducts, engine enclosures and acoustically attenuating shields or shrouds) wherever feasible.
o Except as provided herein, impact tools (e.g., jack hammers, pavement breakers, and rock drills) used for project construction shall be hydraulically or electrically powered to avoid noise associated with compressed air exhaust from pneumatically powered tools.

However, where use of pneumatic tools is unavoidable, an exhaust muffler on the compressed air exhaust shall be used. This muffler can lower noise levels from the exhaust by up to about 10 dBA. External jackets on the tools themselves shall be used, if such jackets are commercially available. this could achieve a reduction of 5 dBA. Quieter procedures shall be used, such as drills rather than impact equipment, whenever such procedures are available and consistent with construction procedures. o Temporary power poles shall be used instead of generators where feasible. o Stationary noise sources shall be located as far from adjacent properties as possible, and they shall be muffled and enclosed within temporary sheds, incorporate insulation barriers, or use other measures as determined by the City to provide equivalent noise reduction.
o The noisiest phases of construction shall be limited to less than 10 days at a time.

Exceptions may be allowed if the City determines an extension is necessary and all available noise reduction controls are implemented.
o Delivery of materials shall observe the hours of operation described above. Truck traffic should avoid residential areas to the extent possible.
● Require new development to minimize vibration impacts to adjacent uses during demolition and construction. For sensitive historic structures, a vibration limit of 0.08 in/sec PPV (peak particle velocity) will be used to minimize the potential for cosmetic damage to the building. A vibration limit of 0.30 in/sec PPV will be used to minimize the potential for cosmetic damage at buildings of normal conventional construction.

Lake Forest Municipal Code
The Project operational noise impacts are governed by the Lake Forest Municipal Code, Chapter 11.16, Noise Control. The following sections of the Municipal Code are relevant to the Project.

Municipal Code Section 11.16.040, Exterior Noise Standards A. The following exterior noise standards set limits for noise that land uses are allowed to generate as received by other land uses. These standards may be used during code enforcement of potential noise violations. For purposes of determining potential project impacts during environmental impact review processes pursuant to the California Environmental Quality Act ("CEQA"), the average hourly level (Leq) standards shall be utilized unless all sources are impact in nature. The standards shall apply to the corresponding land use in residential and mixed-use zones only. It is unlawful for any person to create any noise either within or outside the City due to a stationary noise source (or any mobile noise source not pre-empted by State or Federal laws), Item: 11
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or to allow the creation of any noise on property owned, leased, occupied, or otherwise controlled by such person, which causes the noise level when measured at the property line of any residential use in a residential or mixed-use zone, to exceed the applicable noise standards listed in Table 1—Exterior Noise Standards:

Table 1—Exterior Noise Standards
Land Use Noise Level
(dBA Leq)
Noise Level
(dBA Leq) Time Period
Residential in Residential Zones 60 80 7:00 a.m. to 10:00 p.m. 50 70 10:00 p.m. to 7:00 a.m.

Residential Portion of Mixed-Use in
Mixed-Use Zones
65 85 7:00 a.m. to 10:00 p.m.
50 70 10:00 p.m. to 7:00 a.m.

Places of Worship, Hospitals, and
Schools in Residential and Mixed-Use
Zones
65 85 All hours
Places of Worship, Hospitals, and
Schools in Commercial and Industrial
Zones
70 90 All hours
B. In the event the alleged offensive noise consists entirely of impulsive noise, simple tone noise, amplified speech, music, or any combination thereof, each of the above noise levels shall be reduced by five dBA. Such noises are generally considered to be particularly annoying and are a primary source of noise complaints.

C. If the alleged offense affects a property outside the City's jurisdiction, the exterior noise standards shall be enforced at the City boundary.

D. In the event the measured ambient noise level exceeds any of the noise limit categories above, the noise limit as applied to the contribution of the source(s) in question shall be the ambient noise level.

E. If the noise source and the affected property are within different land use categories, the noise standards of the affected property shall apply.

F. For mixed-use residential land uses affected by noise on the same property (e.g., commercial sources affecting the residential portion of the same property), the exterior noise standard shall be applicable at exterior areas provided for private or common usable open space purposes.

Private usable open space is defined as usable open space intended for use by occupants of one dwelling unit, normally including yards, decks, and balconies. Common usable open space is defined as open space intended for common use by any/all residents of a development, including swimming pools, recreation courts, patios, open landscaped areas, and greenbelts with pedestrian walkways and bicycle trails, but not including off-street parking and loading areas or driveways. If no balcony or private open space is provided for a residential unit, the noise limit shall be applicable at the exterior of accessible openings (doors and windows) to the unit.

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Municipal Code Section 11.16.050, Exemptions
D. Noise sources associated with Construction, repair, remodeling, or grading of any real property, provided that: (1) the City has issued a building permit, grading permit, or similar permit for such activities; (2) said activities do not take place between the hours of 8:00 p.m. and 7:00 a.m., Monday through Saturday, or at any time on Sunday or a legal City of Lake Forest holiday; and (3) the average construction noise levels do not exceed 80 dBA Leq at the first floor of nearby noisesensitive residential uses.

E. Noise sources associated with solid waste collection and removal, provided such activities take place in accordance with LFMC Section 16.05.000(D).

Municipal Code Section 11.16.060, Construction
The following regulations established hours, allowed maximum noise levels, and best management practices for construction noise that occurs within the City of Lake Forest. These standards may be used during code enforcement of potential noise violations or used to determine potential project impacts during environmental review processes pursuant to the California Environmental Quality Act ("CEQA").

The following is required for construction:

A. Construction activities, including delivery of material or equipment, shall not take place between the hours of 8:00 p.m. and 7:00 a.m., Monday through Saturday, or at any time on Sunday or a City holiday; and the average construction noise levels shall not exceed 80 dBA Leq (one-hour) on the first floor of nearby noise-sensitive land uses.

B. If construction noise has the potential to exceed the standards in Section 11.16.090(A), as determined by code enforcement of noise violations, analysis of potential construction noise impacts during a review pursuant to the California Environmental Quality Act, or if construction using heavy equipment is proposed within 100 feet of noise-sensitive land uses, a construction noise management plan shall be prepared by a qualified acoustician and submitted by the applicant. The noise reduction measures shall be determined in the plan and shall be quantified to demonstrate that noise levels would not exceed the standards.

Municipal Code Section 11.16.090, Vibration
A. Operating or permitting the operation of any device that creates vibration that exceeds current published Caltrans vibration criteria at a receiving vibration-sensitive land use is prohibited.

B. For projects implementing a phase or phases of construction that incorporate equipment as presented in Table 2 below: during the pre-building permit issuance phase and after a specific equipment list has been determined: (1) a qualified structural engineer, as approved by the Director of Community Development, or designee, shall identify all structures that are located within the distances established in Table 2 and that have the potential to be affected by groundborne vibration originating from the construction; and (2) a qualified acoustical engineer shall compile a list of proposed construction equipment and compare to the City's accepted vibration criteria. If it is determined that the proposed equipment would generate vibration levels below the City's standard of 0.3 inches per second (in/sec) peak particle velocity (PPV), no further Item: 11
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vibration assessment is necessary. However, if vibration levels would potentially exceed the City's standard of 0.3 in/sec PPV, the project applicant shall develop a vibration monitoring and construction contingency plan for approval by the Director of Community Development, or designee, to ensure that vibration levels would not exceed the City's accepted vibration damage criteria of 0.3 in/sec PPV. If a vibration monitoring and construction contingency plan is deemed necessary, monitoring of vibration during initial construction activities shall be required.

Monitoring results may indicate the need for more or less intensive measurements. The vibration monitoring and construction contingency plan, at the discretion of the Director of Community Development or designee, shall include the following items as necessary:

1. Identification of structures where monitoring would be conducted;

2. A vibration monitoring schedule;

3. Defined structure-specific vibration limits;

4. Photographic, elevation, and crack surveys to document before and after construction conditions; and

5. Identification of construction contingencies for when vibration levels approach the limits.

When vibration levels approach the limits specified in this chapter, construction shall be suspended and contingencies identified in the approved vibration monitoring and construction contingency plan shall be implemented as necessary to lower vibration levels. For some projects, the ability to shield or protect the affected building from potential vibration impacts may be possible as an alternative to changing construction methods.

Table 2—Vibration Assessment Guidelines
Phase of Construction Distance (ft)
Grading
-Large equipment
*Example: D9 dozer, loaded dump truck 15
-Impact hand tools
*Example: Jackhammer 10
Pile Driving
-Impact pile driver 300 or within 5 times the depth of the pile, whichever is less
-Vibratory pile driver 150 or within 5 times the depth of the pile, whichever is less

EXISTING NOISE ENVIRONMENT
Existing Ambient Noise Levels
Some land uses are considered more sensitive to intrusive noise than others based on the types of activities typically involved at the receptor location. Based on a review of the land uses in vicinity of the Project site, the Noise Impact Study identified a total of six noise sensitive receptor locations to represent nearest noise sensitive uses (including residential and school) surrounding the Project site. The locations Item: 11
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of the six noise-sensitive receptors are identified as R1 through R6 in Figure 2 of the Noise Impact Study; refer to Appendix H. A descriptions of the noise receptor locations is provided below. • Sensitive Receptor R1 consists of multi-family residential uses located on the north side of Alton Parkway, approximately 1,570 feet north of the Project site. • Sensitive Receptor R2 consists of single-family residential uses located at the cul-de-sac of Blanco, approximately 1,910 feet northeast of the Project site. • Sensitive Receptor R3 consists of multi-family residential uses located on the south side of Bake Parkway, approximately 1,610 feet southeast of the Project site. • Sensitive Receptor R4 consists of single-family residential uses located on the north side of Newton, approximately 2,015 feet southwest of the Project site. • Sensitive Receptor R5 consists of multi-family residential uses located on the south side of Indigo Place, approximately 665 feet northwest of the Project site. • Sensitive Receptor R6 consists of Guidepost Montessori and Alpha School Lake Forest, located at 26462 Towne Centre Drive, approximately 760 feet north of the Project site.

As part of the Noise Impact Study, two 15-minute measurements, one during the daytime hours (between 10 a.m. and 12 p.m.) and another during the nighttime hours (between 10 p.m. and 12 a.m.), were conducted at the off-site receptor locations, on July 14, 2025. Table 4-17, Existing Ambient Noise Levels, presents the measured ambient noise levels at the sensitive noise receptors located in the vicinity of the Project site in Leq (average sound level). Based on field observation and measured sound data, the current ambient noise environment in the vicinity of the Project site is controlled primarily by vehicular traffic on nearby roadways (i.e., Alton Parkway, Portola Parkway, Bake Parkway, Towne Centre Drive, and SR-241).

Asindicated in Table 4-17, the existing daytime ambient noise levels ranged from 43.7 dBA Leq at receptor R2 to 63.8 dBA Leq at receptor R3. The existing nighttime ambient noise levels ranged from 37.6 dBA Leq at receptor R4 to 53.7 dBA Leq at receptor R3. The existing ambient noise levels are below the City’s exterior noise standards of 60 dBA Leq during daytime hours and 50 dBA Leq during the nighttime hours at receptors R1, R2, R4, R5 and R6.

Table 4-17
Existing Ambient Noise Levels
Measured Ambient Noise Levels
Location1 Noise-Sensitive Land Use Daytime Hours
(between 10 a.m. and 12 p.m.)
Nighttime Hours
(between 10 p.m. and 12 a.m.)
R1 Residential 52.6 48.5
R2 Residential 43.7 41.5
R3 Residential 63.8 53.7
R4 Residential 50.9 37.6
R5 Residential 49.4 44.3
R6 School 50.02 40.02
Source: Acoustical Engineering Services, Inc., Environmental Noise Impact Study, Costco Wholesale Warehouse Project Foothill Ranch, California, January 2026.

Notes:

1. Noise level monitoring locations are illustrated in Figure 2 of the Noise Impact Study; refer to Appendix H.

2. Estimated based on nearby measurements.

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SIGNIFICANCE THRESHOLDS
The Project significance thresholds are based on the City’s General Plan and Municipal Code as described above, and the City’s CEQA Significance Thresholds Guide. 21 The project would normally have significant construction noise impacts if it would:
• Exceed 80 dBA Leq (1-hour) between the hours of 7:00 a.m. and 8:00 p.m., Monday through Saturday.22
Per the City’s CEQA Significance Thresholds Guide, the project would normally have significant vibration impacts if it would exceed the applicable standards from the Federal Transit Administration (FTA) or Caltrans. Therefore, based on FTA standards as described above, the project would result in significant vibration impacts if:
• Project construction activities cause ground-borne vibration levels to exceed 0.5 PPV at the nearest off-site non-engineered timber and masonry building (typical woodframe buildings). • Project construction activities cause ground-borne vibration levels to exceed 75 VdB at off-site residential uses or 78 VdB at off-site school uses.

The operational noise impacts would be considered significant if:
• The noise level generated by on-site noise sources would exceed the City’s exterior noise standards or the measured ambient noise levels, whichever is greater, as follows:
o At residential uses: 60 dBA (Leq) during the daytime hours (between 7:00 a.m. and 10:00 p.m.) and 50 dBA (Leq) during the nighttime hours (between 7:00 a.m. and 10:00 p.m.). o At school site uses: 65 dBA (Leq) at all hours.
• The noise level generated by off-site traffic results in:
o An increase the 3 dBA CNEL when the existing noise levels are between 60 dBA and 65 dBA CNEL, or
o An increase of 1.5 dBA CNEL when the existing noise levels exceed 65 dBA CNEL. 21 City of Lake Forest, Appendix A: City Of Lake Forest CEQA Significance Thresholds Guide, November 20, 2001 (revised May 6, 2025).
22 Per the City, construction is prohibited between 8:00 p.m. and 7:00 a.m., Monday through Saturday, or at any time on Sunday or a City holiday.

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a) A proposed project would normally have a significant offsite traffic noise impact if both of the following criteria are met:
1) Project traffic will cause a noise level increase of 3dB or more on a roadway segment adjacent to a noise sensitive land use. Noise sensitive land uses include the following:
residential (single-family, multi-family, mobile home); hotels; motels; nursing homes; hospitals; parks, playgrounds and recreation areas; and schools. 2) The resulting “future with project” noise level exceeds the noise standard for sensitive land uses as identified in the City of Lake Forest General Plan (refer to Table 3-1 in Section 3.3 Interior and Exterior Noise Standards).

As part of the Noise Impact Study, Project-generated traffic noise impacts were evaluated by comparing the increase in noise levels from the “future without project” condition to the “future with project” condition with the Project’s significance threshold. Based on this analysis, the Noise Impact Study concludes that the Project would result in a maximum noise increase of 2.5 dBA CNEL (relative to the “future without project” conditions) along Town Centre Drive (between Alton Parkway and Bake Parkway). The estimated traffic noise levels along Alton Parkway (East of Portola Parkway), Rancho Parkway, Town Center Drive (between Alton Parkway and Bake Parkway), and Portola Parkway (North of Alton Parkway) fall between 60 dBA and 65 dBA CNEL, which would be below the 3 dBA CNEL significance threshold (applicable to noise levels between 60 dBA and 65 dBA CNEL). The noise increase at all other roadway segments is less than 1.2 dBA CNEL, which would be below the 1.5 dBA CNEL significance threshold (applicable to noise levels greater than 65 dBA CNEL).

An additional analysis was performed to determine the potential noise impacts based on the increase in noise levels due to Project-related traffic (“existing with project” conditions) compared with the “existing without project” noise conditions. Based on this analysis, the Noise Impact Study concludes that traffic from the Project would result in a maximum noise increase of 2.6 dBA CNEL (relative to the “existing without project” conditions) along Towne Centre Drive (between Alton Parkway and Bake Parkway). The estimated traffic noise levels along Alton Parkway (East of Portola Parkway), Rancho Parkway, Town Center Drive (between Alton Parkway and Bake Parkway), and Portola Parkway (North of Alton Parkway) fall between 60 dBA and 65 dBA CNEL, which would be below the 3 dBA CNEL significance threshold. The noise increase at all other roadway segments is less than 1.3 dBA CNEL, which would be below the 1.5 dBA CNEL significance threshold.

The Project combined with the future growth and related projects in the area would produce traffic (i.e., off-site mobile sources) that would generate cumulative traffic roadway noise. Cumulative noise impacts due to off-site traffic were analyzed by comparing the projected increase in traffic noise levels from “existing conditions” to “future plus Project” conditions to the applicable significance criteria. Based on this analysis, the Noise Impact Study concludes that cumulative traffic would result in a maximum noise increase of 2.8 dBA CNEL along Towne Centre Drive (between Alton Parkway and Bake Parkway). The estimated traffic noise levels along Alton Parkway (East of Portola Parkway), Rancho Parkway, Town Center Drive (between Alton Parkway and Bake Parkway), and Portola Parkway (North of Alton Parkway) fall between 60 dBA and 65 dBA CNEL, which would be below the 3 dBA CNEL significance threshold. The noise increase at all other roadway segments are 1.4 dBA CNEL or lower, which would be below the 1.5 dBA CNEL significance threshold. Therefore, noise impacts associated with off-site traffic would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Item: 11
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Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.
b) Exceed the stationary noise criteria for the City of Lake Forest as specified by the exterior noise standards set forth in the Noise Control Chapter of the Lake Forest Municipal Code? Short-Term Construction Noise Impacts
Noise impacts from Project construction activities would be a function of the noise generated by construction equipment, the location of the equipment, the timing and duration of the noise-generating construction activities, and the relative distance to noise-sensitive receptors. Construction activities for the Project would generally include demolition, site grading and excavation, building construction, and landscaping. Each stage of construction would involve the use of various types of construction equipment and would, therefore, have its own distinct noise characteristics. Demolition would involve the use of excavators, breakers, backhoes, and heavy-duty trucks. Grading and excavation would require the use of graders, excavators, breakers, jackhammers, backhoes, compactors, and heavy-duty trucks. Building construction would involve the use of air compressors, cranes, concrete trucks, paving trucks, compactors, and delivery trucks. Landscaping would involve the use of backhoes and work trucks. Noise from construction equipment would generate both steady-state and episodic noise that could be heard within and adjacent to the Project site.

Typical noise levels associated with construction equipment are shown in Table 4-18, Typical Construction Equipment Noise Levels. As shown, individual pieces of construction equipment that would be used for construction of the Project produce maximum noise levels of 74 dBA to 90 dBA at a reference distance of 50 feet from the noise source. The construction equipment noise levels at 50 feet distance (Referenced Maximum Noise Levels) are based on the FHWA Roadway Construction Noise Model User’s Guide, which is a technical report containing actual measured noise data for construction equipment. These maximum noise levels would occur when equipment is operating under full power conditions (i.e., the equipment engine at maximum speed). However, equipment used on construction sites often operates under less than full power conditions, or part power. To more accurately characterize construction-period noise levels, the average (Hourly Leq) noise level associated with each construction stage is calculated based on the quantity, type, and usage factors for each type of equipment that would be used during each construction stage. These noise levels are typically associated with multiple pieces of equipment operating simultaneously.

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Table 4-18
Typical Construction Equipment Noise Levels
Type of Equipment Acoustical Usage Factor (%)1 Reference Maximum Noise Levels at 50 Feet, Lmax (dBA)2
Air Compressor 40 78
Backhoe 40 78
Cement and Mortar Mixers 50 80
Concrete Mixer Truck 40 79
Concrete Saw 20 90
Crane 16 81
Dozer 40 82
Dump/Haul Truck 40 76
Excavator 40 81
Forklift 20 75
Generator 50 81
Loader 40 79
Paving Equipment 50 77
Rollers 20 80
Tractors/Loaders/Backhoes 40 84
Water Truck 10 82
Welders 40 74
Source: Acoustical Engineering Services, Inc., Environmental Noise Impact Study, Costco Wholesale Warehouse Project Foothill Ranch, California, January 2026.

Notes:

1. The usage factor is the estimated percentage of time during an 8-hour day that a piece of construction equipment is operating at full power.

2. Construction equipment noise levels are based on the FHWA Roadway Construction Noise Model User’s Guide.

Construction, generally, would start with the demolition of existing structures, follow by site preparation and grading, building construction, paving/landscaping, and architectural coating. Table 4-19, On-Site Construction Noise Impacts, provides the estimated, unmitigated construction noise levels at the off-site noise sensitive receptors by construction phase. To present a conservative noise impact analysis, the estimated noise levels were calculated with all pieces of construction equipment assumed to be operating simultaneously and located at the construction area nearest to the affected receptors. As indicated in 4- 19, the estimated construction noise levels would be below the Project significance threshold (80 dBA) at all off-site noise receptors.

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Table 4-19
On-Site Construction Noise Impacts
Receptor
Location
Estimated Construction Noise Levels by Phase, dBA (Leq) Significance Threshold
dBA (Leq)
1 Significant
Demolition Impact? Site
Prep Grading Building Construction Paving Architectural Coating R1 55.6 59.3 60.3 56.1 53.1 44.1 80.0 No
R2 54.0 58.3 59.2 54.5 52.1 42.4 80.0 No
R3 51.8 55.4 56.3 50.9 49.2 38.9 80.0 No
R4 50.8 51.8 52.8 49.0 45.6 36.9 80.0 No
R5 63.1 66.3 67.2 63.2 60.2 51.5 80.0 No
R6 60.6 68.3 68.8 62.0 61.8 50.4 80.0 No
Source: Acoustical Engineering Services, Inc., Environmental Noise Impact Study, Costco Wholesale Warehouse Project Foothill Ranch, California, January 2026.

Notes:

1. Significance thresholds are equivalent to the City’s daytime construction noise limits of 80 dBA.

The construction phases of the Project would have the potential to overlap. Therefore, overlapping construction noise activities were evaluated to determine the potential impacts. Construction noise impacts associated with the overlapping construction are provided in Table 4-20, On-Site Construction Noise Impacts – Overlapping Construction. As indicated in Table 4-20, the estimated noise levels due to overlapping construction activities would be below the Project significance threshold (80 dBA) at all offsite receptor locations. Therefore, temporary noise impacts associated with the Project’s on-site construction would be less than significant. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.

Table 4-20
On-Site Construction Noise Impacts – Overlapping Construction Receptor
Location
Estimated Construction Noise Levels by Phase, dBA (Leq) Significance Threshold
dBA (Leq)
1 Significant
Impact? Grading + Building
Construction
Building
Construction
+ Paving
Building Construction
+ Paving +
Architectural Coating
R1 61.7 57.9 58.0 80.0 No
R2 60.5 56.5 56.6 80.0 No
R3 57.4 53.1 53.3 80.0 No
R4 54.3 50.6 50.8 80.0 No
R5 68.7 65.0 65.2 80.0 No
R6 69.6 64.9 65.1 80.0 No
Source: Acoustical Engineering Services, Inc., Environmental Noise Impact Study, Costco Wholesale Warehouse Project Foothill Ranch, California, January 2026.

Notes:

1. Significance thresholds are equivalent to the City’s daytime construction noise limits of 80 dBA.

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Long-Term Operational Noise Impacts
On-site operation noise levels associated with the Project would include on-site mechanical equipment, loading dock operation, warehouse delivery trucks, trash compactors, parking lot operation, parking lot cleaning, and operation of the tire installation center.

Mechanical
The Project would include mechanical equipment (e.g., air ventilation equipment and emergency generator), which would be located at the roof level and/or placed within the building structure. Projectrelated outdoor mechanical equipment would be designed to comply with the City’s exterior noise standards. Table 4-21, Mechanical Noise Levels presents the estimated on-site mechanical equipment noise levels at the off-site receptor locations. As shown on Table 4-21, the estimated noise levels from the mechanical equipment would range from 30.9 dBA (Leq) at receptor location R2 to 39.4 dBA (Leq) at receptor location R5, which would be below the Project significance thresholds. As such, noise impacts from the Project mechanical equipment would be less than significant.

Table 4-21
Mechanical Noise Levels
Receptor
Location
Existing Ambient
Noise Levels,
dBA (Leq)
Estimated Noise
from Mechanical
Equipment,
dBA (Leq)
Significance
Threshold
dBA (Leq)
1 Exceed over
Significance
Threshold,
dBA (Leq)
Significant
Impact?
R1 48.5 33.1 50.0 0.0 No
R2 41.5 30.9 50.0 0.0 No
R3 53.7 31.7 50.0 0.0 No
R4 37.6 31.4 50.0 0.0 No
R5 44.3 39.4 50.0 0.0 No
R6 40.0 38.3 65.0 0.0 No
Source: Acoustical Engineering Services, Inc., Environmental Noise Impact Study, Costco Wholesale Warehouse Project Foothill Ranch, California, January 2026.

Notes:

1. Significance threshold equal to City’s nighttime noise limits.

Loading Dock Operation
The Project includes a loading dock, which is planned to be located at the southeast corner of the warehouse building. The loading dock includes four loading bays. Noise sources associated with the loading dock would include delivery truck loading/unloading of goods. Based on measured noise levels from typical loading dock facilities, delivery trucks could generate noise levels of approximately 64.7 dBA (Leq) at a distance of 100 feet. The noise analysis assumed maximum of four delivery trucks loading/unloading simultaneously to represent a conservative analysis. Table 4-22, Loading Dock Operation Noise Levels, presents the estimated noise levels associated with the loading dock operations at the off-site receptor locations. As shown, the estimated noise levels from the loading dock range from

12.8 dBA (Leq) at receptor R2 to 36.8 dBA (Leq) at receptor location R4, which would be below the Project significance thresholds. Therefore, noise impacts from the loading dock operations would be less than significant.

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Table 4-22
Loading Dock Operation Noise Levels
Receptor
Location
Existing Ambient
Noise Levels,
dBA (Leq)
Estimated Noise
from Loading Dock
Operation,
dBA (Leq)
Significance
Threshold
dBA (Leq)
1 Exceed over
Significance
Threshold,
dBA (Leq)
Significant
Impact?
R1 48.5 15.0 50.0 0.0 No
R2 41.5 12.8 50.0 0.0 No
R3 53.7 19.6 50.0 0.0 No
R4 37.6 36.8 50.0 0.0 No
R5 44.3 25.0 50.0 0.0 No
R6 40.0 20.8 65.0 0.0 No
Source: Acoustical Engineering Services, Inc., Environmental Noise Impact Study, Costco Wholesale Warehouse Project Foothill Ranch, California, January 2026.

Notes:

1. Significance threshold equal to City’s nighttime noise limits.

Warehouse Delivery Trucks
The warehouse deliveries would take place between 2:00 a.m. and 10:00 a.m. with 14 to 16 deliveries per day, and with a maximum of two deliveries per hour. The noise analysis assumed the delivery trucks would enter and leave the Project site through Portola Parkway and Bake Parkway. Table 4-23, Warehouse Delivery Truck Noise Levels, presents the estimated noise levels associated with the warehouse delivery trucks at the off-site noise sensitive receptors. As indicated in Table 4-23, the estimated noise levels from the warehouse delivery truck operation range from 26.0 dBA (Leq) at receptor R1 to 49.3 dBA (Leq) at receptor location R3, which would be below the significance threshold. Therefore, noise impacts from the warehouse delivery trucks would be less than significant.

As demonstrated above, the estimated noise levels associated with warehouse delivery trucks would be below the City’s nighttime noise limit. Furthermore, a noise analysis has been prepared to address the potential sleep disturbance using the Sound Exposure Level (SEL). It should be noted that the SEL analysis with respect to potential sleep disturbance is mainly applicable to aviation related noises. Currently, there are no noise standards, or limit, to address traffic noise impacts on sleep (sleep disturbance), using SEL noise descriptor. Therefore, the recommended SEL noise limit from the LAX South Airfield Improvement Project EIR (LAX EIR) was used to evaluate potential sleep disturbance for the Project, which specified a maximum 81 dBA SEL at the interior of the residence. Per the LAX EIR, buildings with window open would provide approximately 13 dBA exterior/interior noise reduction. Therefore, based on the interior noise limit of 81 dBA SEL and typical noise reduction of a building with window open of 13 dBA, the maximum exterior noise limit would be 94 dBA SEL, which is the considered threshold for the sleep disturbance to occur. The estimated SEL due to a delivery truck would range from 58.6 dBA SEL at the exterior of receptor R1 (nearest residences to the north) to 81.9 dBA SEL at the exterior of receptor R3 (nearest residence to the east). As analyzed, the estimated SEL levels at the off-site sensitive receptors would be below the 94 dBA SEL exterior noise limits. In addition, the estimated SEL at the interior of the nearest residences, with the window opens (worst-case noise scenario) would be approximately 45.6 (nearest residences to the north) to 68.9 dBA SEL (residences to the east), which would be below the 81 dBA SEL interior noise limits.

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Table 4-23
Warehouse Delivery Truck Noise Levels
Receptor
Location
Existing Ambient
Noise Levels,
dBA (Leq)
Estimated Noise from
Delivery Trucks,
dBA (Leq)
Significance
Threshold
dBA (Leq)
1 Exceed over
Significance
Threshold,
dBA (Leq)
Significant
Impact?
R1 48.5 26.0 50.0 0.0 No
R2 41.5 35.6 50.0 0.0 No
R3 53.7 49.3 50.0 0.0 No
R4 37.6 40.9 50.0 0.0 No
R5 44.3 30.2 50.0 0.0 No
R6 40.0 39.3 65.0 0.0 No
Source: Acoustical Engineering Services, Inc., Environmental Noise Impact Study, Costco Wholesale Warehouse Project Foothill Ranch, California, January 2026.

Notes:

1. Significance threshold equal to City’s nighttime noise limits.

Trash Compactors
The Project includes two trash compactors located along the east side of the warehouse building. The trash compactors would operate during the daytime hours between 9:30 a.m. and 8:30 p.m. Based on measured noise levels from typical trash compactor, a trash compactor could generate noise levels of approximately 65.5 dBA (Leq) at 50 feet. The noise analysis assumed both trash compactors would operate simultaneously to represent a conservative analysis. Table 4-24, Trash Compactors Operation Noise Levels, presents the estimated noise levels associated with the trash compactors operation at the off-site receptor locations. As shown, the estimated noise levels from the trash compactors range from

8.7 dBA (Leq) at receptor R2 to 41.6 dBA (Leq) at receptor location R5, which would be below the Project significance thresholds. Therefore, noise impacts from the trash compactors operation would be less than significant.

Table 4-24
Trash Compactors Operation Noise Levels
Receptor Location
Existing
Ambient
Noise Levels,
dBA (Leq)
Estimated
Noise from
Trash
Compactors,
dBA (Leq)
Significance
Threshold
dBA (Leq)
1 Exceed over
Significance
Threshold,
dBA (Leq)
Significant
Impact?
R1 52.6 11.4 60.0 0.0 No
R2 43.7 8.7 60.0 0.0 No
R3 63.8 11.0 60.0 0.0 No
R4 50.9 28.9 60.0 0.0 No
R5 49.4 41.6 60.0 0.0 No
R6 50.0 16.2 65.0 0.0 No
Source: Acoustical Engineering Services, Inc., Environmental Noise Impact Study, Costco Wholesale Warehouse Project Foothill Ranch, California, January 2026.

Notes:

1. Significance threshold equal to City’s daytime noise limits.

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Parking Lot Operation
The Project parking lot includes 913 parking spaces mostly along the eastern and southern sides of the Project Site. Sources of noise within the parking lot would primarily include vehicular movements and engine noise, sounding of doors opening and closing, and people talking. Noise levels within the parking structure would fluctuate with the amount of automobile and human activity. Table 4-25, Parking Lot Operation Noise Levels, presents the estimated noise levels associated with the parking lot at the off-site receptor locations. As shown on Table 4-25, the estimated noise levels from the parking lot range from

33.3 dBA (Leq) at receptor R1 to 44.5 dBA (Leq) at receptor location R6, which would be below the existing ambient noise levels. As such, the estimated noise levels at all off-site receptor locations would be below the significance thresholds. Therefore, noise impacts from the parking lot operations would be less than significant.

Table 4-25
Parking Lot Operation Noise Levels
Receptor Location
Existing Ambient
Noise Levels,
dBA (Leq)
Estimated Noise
from Parking
Lot,
dBA (Leq)
Significance
Threshold
dBA (Leq)
1 Exceed over
Significance
Threshold,
dBA (Leq)
Significant
Impact?
R1 52.6 33.3 60.0 0.0 No
R2 43.7 34.2 60.0 0.0 No
R3 63.8 35.2 60.0 0.0 No
R4 50.9 36.7 60.0 0.0 No
R5 49.4 34.4 60.0 0.0 No
R6 50.0 44.5 65.0 0.0 No
Source: Acoustical Engineering Services, Inc., Environmental Noise Impact Study, Costco Wholesale Warehouse Project Foothill Ranch, California, January 2026.

Notes:

1. Significance threshold equal to City’s daytime noise limits.

Parking Lot Cleaning
In addition, the parking lot will be cleaned with a vacuum truck. The parking lot cleaning would typically occur during the early morning or late evening hours (before and after the warehouse opens and closes).

Reference noise level for a typical vacuum street sweeper, as published by the FHWA RCNM, is approximately 72 dBA (Leq) at 50 feet. Table 4-26, Parking Lot Cleaning Noise Levels, presents the estimated noise levels associated with the parking lot at the off-site receptor locations. As shown on Table 4-26, the estimated noise levels from the parking lot range from 34.9 dBA (Leq) at receptor R1 to 46.7 dBA (Leq) at receptor location R6, which would be below the significance thresholds. Therefore, noise impacts from the parking lot cleaning would be less than significant.

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Table 4-26
Parking Lot Cleaning Noise Levels
Receptor Location
Existing Ambient
Noise Levels,
dBA (Leq)
Estimated Noise
from Parking Lot
Cleaning,
dBA (Leq)
Significance
Threshold
dBA (Leq)
1 Exceed over
Significance
Threshold,
dBA (Leq)
Significant
Impact?
R1 48.5 33.1 50.0 0.0 No
R2 41.5 34.8 50.0 0.0 No
R3 53.7 35.8 50.0 0.0 No
R4 37.6 38.2 50.0 0.0 No
R5 44.3 43.9 50.0 0.0 No
R6 40.0 44.9 65.0 0.0 No
Source: Acoustical Engineering Services, Inc., Environmental Noise Impact Study, Costco Wholesale Warehouse Project Foothill Ranch, California, January 2026.

Notes:

1. Significance threshold equal to City’s nighttime noise limits.

Tire Installation Center
The Project includes a member-only tire installation center, located at the west side of the warehouse building. Typical operations within the tire installation center would include various noise sources including wheel balancers, tire changers, air-compressors, and pneumatic tools. Based on previous noise measurements made at a similar Costco facility, operation of the member-only tire installation center would generate average noise levels of approximately 65 dBA (Leq), at a distance of 50 feet from the tire installation center open bay doors. Table 4-27, Tire Installation Center Noise Levels, presents the estimated noise levels associated with the parking lot at the off-site receptor locations. As shown on Table 4-27, the estimated noise levels from the parking lot range from 9.0 dBA (Leq) at receptor R4 to 32.7 dBA (Leq) at receptor location R6, which would be below the significance thresholds. Therefore, noise impacts from the tire installation center would be less than significant.

Table 4-27
Tire Installation Center Noise Levels
Receptor
Location
Existing Ambient
Noise Levels,
dBA (Leq)
Estimated Noise
from Tire Installation
Center,
dBA (Leq)
Significance
Threshold
dBA (Leq)
1 Exceed over
Significance
Threshold,
dBA (Leq)
Significant
Impact?
R1 52.6 27.9 60.0 0.0 No
R2 43.7 29.0 60.0 0.0 No
R3 63.8 30.0 60.0 0.0 No
R4 50.9 9.0 60.0 0.0 No
R5 49.4 11.5 60.0 0.0 No
R6 50.0 32.7 65.0 0.0 No
Source: Acoustical Engineering Services, Inc., Environmental Noise Impact Study, Costco Wholesale Warehouse Project Foothill Ranch, California, January 2026.

Notes:

1. Significance threshold equal to City’s daytime noise limits.

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Composite On-Site Operational Noise Impacts
An evaluation of composite operational noise levels, including all Project on-site noise sources plus existing ambient noise levels, was conducted to identify the potential Project-related noise level increase that may occur at the noise-sensitive receptor locations. On-site noise sources associated with the Project would include mechanical equipment, loading dock operation, warehouse delivery trucks, trash compactors, parking lot operation (including parking lot cleaning), and tire center. Table 4-28, Composite On-Site Operational Noise Levels, presents the estimated daytime and nighttime noise levels from Projectrelated on-site noise sources at the off-site noise receptors. As indicated in Table 4-28, the estimated daytime composite noise levels due to the Project would range from 38.6 dBA (Leq) at receptor R1 to 49.8 dBA (Leq) at receptor R3, which would be below the Project daytime significance threshold of 60.0 dBA (Leq) at receptors R1 through R3 and 65.0 dBA (Leq) at receptor R6. The estimated nighttime composite noise levels due to the Project would range from 36.5 dBA (Leq) at receptor R1 to 49.6 dBA (Leq) at receptor R3, which would be below the Project nighttime significance threshold of 50.0 dBA (Leq) at receptors R1 through R3 and 65 dBA (Leq) at receptor R6. Therefore, the composite noise level impacts due to Project operation would be less than significant, consistent with the 2040 General Plan FEIR.

Table 4-28
Composite On-Site Operational Noise Impacts
Receptor
Location
Project Composite Noise
Levels, dBA (Leq)
Ambient Noise
Levels, dBA (Leq)
Significance Threshold
dBA (Leq)
1 Significant
Impact?
Daytime Hours
R1 38.6 52.6 60.0 No
R2 40.5 43.7 60.0 No
R3 49.8 63.8 60.0 No
R4 44.8 50.9 60.0 No
R5 47.1 49.4 60.0 No
R6 48.8 50.0 65.0 No
Nighttime Hours
R1 36.5 48.5 50.0 No
R2 39.0 41.5 50.0 No
R3 49.6 53.7 50.0 No
R4 44.0 37.6 50.0 No
R5 45.4 44.3 50.0 No
R6 46.7 40.0 65.0 No
Source: Acoustical Engineering Services, Inc., Environmental Noise Impact Study, Costco Wholesale Warehouse Project Foothill Ranch, California, January 2026.

Notes:

1. Significance threshold equal to City’s daytime and nighttime noise limits.

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c) Generation of excessive groundborne vibration or groundborne noise levels? Construction activities can generate varying degrees of ground vibration, depending on the construction procedures and the type of construction equipment used. The operation of construction equipment generates vibrations that travel through the ground and diminish in amplitude with distance from the source. The effect on buildings located in the vicinity of the construction site often varies, depending on soil type, ground strata, and construction characteristics of the receptor buildings.

Regarding potential building damage, the Project would generate ground-borne construction vibration forces during the demolition, site preparation, grading, and paving phases when heavy construction equipment, such as vibratory rollers, large bulldozers, and loaded trucks, would be used. The FTA has published standard vibration velocity levels for various construction equipment operations. Vibration impacts regarding structures are evaluated at the nearest off-site buildings to the Project Site (commercial buildings to the north, south, east and west), whereas the potential for human annoyance associated with construction-related vibration are evaluated at the six human annoyance vibration-sensitive receptor locations (i.e., receptor locations R1 through R6).

Table 4-29, Construction Vibration Impacts – Building Damage, provides the estimated vibration levels (in terms of inch per second PPV) at the nearest off-site structures adjacent to the Project site. To present a worst-case vibration impact analysis, the estimated vibration levels were calculated with the construction equipment assumed to be operating at the closest distance to the nearest off-site building structures. As indicated in Table 4-29, the estimated vibration velocity levels from all construction equipment would be below the building damage significance criteria at all off-site building structures. As such, on-site vibration impacts, pursuant to the significance criteria for building damage, during construction of the Project would be less than significant.

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Table 4-29
Construction Vibration Impacts – Building Damage
Nearest OffSite Building
Structures1
Estimated Vibration Velocity Levels at the Nearest Off-Site Structures from the Project Construction Equipment
inch/second (PPV)2
Significance
Threshold,
inch/second
(PPV)3
Significant
Impact? Vibratory
Roller
Large
Bulldozer
Loaded
Trucks
JackhammerSmall
Bulldozer
Commercial
Buildings to
the North

0.031 0.013 0.011 0.005 <0.001 0.50c No
Commercial
Buildings to
the East

0.057 0.024 0.020 0.009 0.001 0.50c No
Commercial
Buildings
to the South

0.368 0.156 0.133 0.061 0.005 0.50c No
Commercial
Buildings to
the West

0.003 0.001 0.001 <0.001 <0.001 0.50c No
Source: Acoustical Engineering Services, Inc., Environmental Noise Impact Study, Costco Wholesale Warehouse Project Foothill Ranch, California, January 2026.

Notes:

1. Represents off-site building structures located nearest to the Project Site to the north, south, east, and west.

2. Vibration levels calculated based on FTA reference vibration level at 25-foot distance.

3. FTA criteria for non-engineered concrete and masonry buildings.

Table 4-30, Construction Vibration Impacts – Human Annoyance, presents the estimated vibration velocity levels (in terms of VdB) due to construction equipment at the off-site vibration sensitive receptors. To present a worst-case analysis, the estimated vibration levels were calculated with the construction equipment assumed to be operating at the closest distance to the nearest off-site sensitive receptors. As indicated in Table 4-30, the estimated vibration levels due to on-site construction equipment would be below the significance threshold for human annoyance at all off-site vibration sensitive receptors.

Therefore, on-site vibration impacts, pursuant to the significance criteria for human annoyance, during construction of the Project would be less than significant, consistent with the 2040 General Plan FEIR.

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Table 4-30
Construction Vibration Impacts – Human Annoyance
Off-Site
Receptor
Location
Estimated Vibration Velocity Levels at the Nearest Off-Site Sensitive Receptors from the Project Construction
Equipment, VdB1
Significance
Threshold,
VdB
Significant
Impact? Vibratory
Roller
Large
Bulldozer
Loaded
Trucks
JackhammerSmall
Bulldozer
R1 40 33 32 25 4 75 No
R2 38 31 30 23 2 75 No
R3 40 33 32 25 4 75 No
R4 37 30 29 22 1 75 No
R5 51 44 43 36 15 75 No
R6 50 43 42 35 14 78 No
Source: Acoustical Engineering Services, Inc., Environmental Noise Impact Study, Costco Wholesale Warehouse Project Foothill Ranch, California, January 2026.

Notes:

1. Vibration levels calculated based on FTA reference vibration level at 25-foot distance. d) For a project located within the vicinity of a private airstrip or an airport land use plan or, where such a plan has not been adopted, within two miles of a public airport or public use airport, would the project expose people residing or working in the project area to excessive noise levels?
The Project site in not located within an airport land use plan, nor is the Project site located within two miles of a private airstrip, public airport, or public use airport. Thus, the Project would not result in a safety hazard or excessive noise for people residing or working in the Project area. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.

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XIV. Population and Housing
Would the project:

The Project site is designated Mixed-Use 43 (MU-43) and is zoned Mixed-Use 43 in the Foothill Ranch Planned Community. The Project is consistent with the General Plan land use designation and zoning for the site. Employment-generating uses have recently occurred within the site and have been anticipated by the 2040 General Plan. The Project anticipates providing approximately 300 jobs. 23 It should be noted
that estimating the number of future employees who would choose to relocate to the City would be highly speculative since many factors influence personal housing location decisions (i.e., family income levels and the cost and availability of suitable housing in the local area). Assuming the 300 new employees (and their families) relocate to Lake Forest, Project implementation would result in a potential population increase of approximately 834 persons.24 This is a conservative assumption, as it assumes employees would relocate to the City along with their families instead of a scenario of existing Lake Forest residents 23 Kittelson & Associates, Inc., Focused Transportation Impact Study (TIS) Technical Memorandum, November 26, 2025.
24 Based upon an average household size of 2.78 persons per household per the State of California, Department of Finance, E-5 Population and Housing Estimates for Cities, Counties, and the State, 2020-2025, May 2025.

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filling some of the new employment opportunities. It also does not take into the consideration the employees of the recently closed movie theater. The additional increase of 834 persons in the City would increase the City’s existing (2025) population of 87,639 persons25 by less than one percent (approximately

0.95 percent) to 88,473 persons. The 2040 General Plan FEIR estimates a population of 152,462 persons in the City by 2040, constituting an increase of 70,574 people compared to the existing (2019) condition.

The Project would be within the population growth projections anticipated and planned for by the General Plan and would not induce substantial unplanned population growth in the area. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.
b) Displace substantial numbers of existing people or housing, necessitating the construction of replacement housing elsewhere?
The Project site is currently developed with commercial uses and does not contain any housing. Therefore, the proposed Project would not displace substantial numbers of existing people or housing, necessitating the construction of replacement housing elsewhere. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified.

Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.
25 State of California, Department of Finance, E-5 Population and Housing Estimates for Cities, Counties, and the State, 2020-2025, May 2025
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XV. Public Services
Would the project:

Significant
Impact
Peculiar to
the Project or
Project site
Impact
Adequately
Addressed in
the General
Plan EIR
Impact
Substantially
Mitigated by
Uniformly
Applicable
Development
Standards
New
Potentially
Significant
Off-Site or
Cumulative
Impact not
Addressed in
the General
Plan EIR
a. Result in substantial adverse physical
impacts associated with the provision of
new or physically altered governmental
facilities, need for new or physically altered
governmental facilities, the construction of
which could cause significant
environmental impacts, in order to
maintain acceptable service ratios,
response times or other performance
objectives for any of the public services:
1) Fire protection? No Yes No No
2) Police protection? No Yes No No
3) Schools? No Yes No No
4) Parks? No Yes No No
5) Other public facilities? No Yes No No
Discussion: The 2040 General Plan FEIR determined that impacts to public services would be less than significant through the implementation of policies and actions in the 2040 General Plan. a) Would the project result in substantial adverse physical impacts associated with the provision of new or physically altered governmental facilities, need for new or physically altered governmental facilities, the construction of which could cause significant environmental impacts, in order to maintain acceptable service ratios, response times or other performance objectives for any of the public services:
1) Fire protection?
The Orange County Fire Authority (OCFA) provides fire protection and emergency response services to the City, including the Project site. There are three fire stations within Lake Forest. The nearest fire station to the Project site is Station 95, located at 19811 Pauling Avenue, approximately 0.8 miles to the southeast.

The Project proposes to demolish a former movie theater building and construct a new retail warehouse building with a tire service center. Similar to existing conditions, access to the Project site would continue to be provided via existing driveways along Towne Centre Drive and Market Place. These driveways connect to common driveways and drive aisles within the interior of the larger Phase 4 area. As part of Item: 11
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the Project, the common driveway (i.e., Market Place) that extends from Towne Centre Drive between the Project site and the PetSmart building would be partially reconstructed. The existing four-way stop intersection located along the northern boundary of the Project site would be removed and a new threeway stop intersection would be constructed to the east. The existing driveway east of the former movie theater building would also be removed and reconstructed to the east of the proposed Costco Warehouse building.

The proposed Project is not anticipated to result in the need for construction of new or physically altered fire protection facilities. Service to the Project site by the OCFA occurs under existing conditions and Project implementation is not anticipated to significantly increase calls for service or alter response times or other performance objectives that would result in the need for new or substantially altered fire facilities. The Project is consistent with the General Plan land use designation and zoning for the site.

Implementation of Fire Code requirements and approval of site plans by the OCFA would further reduce potential impacts concerning fire protection and emergency services. Therefore, the Project would not significantly impact fire protection and emergency services resulting in the need for new or physically altered facilities. Impacts would be less than significant, consistent with the 2040 General Plan FEIR.

The proposed Project is not anticipated to result in the need for construction of new or physically altered police protection facilities. Service to the Project site by the OCSD occurs under existing conditions and Project implementation is not anticipated to significantly increase calls for service or alter response times or other performance objectives that would result in the need for new or substantially altered police facilities. The Project is consistent with the General Plan land use designation and zoning for the site.

Employment-generating uses have recently occurred within the site and have been anticipated by the 2040 General Plan. Further, the forecast population growth associated with the Project represents an increase of less than one percent (approximately 0.95 percent) in population over existing conditions and is within the growth projections anticipated by the 2040 General Plan; refer to Section XIV, Population and Housing. Therefore, the Project would not significantly impact police protection services resulting in the need for new or physically altered facilities. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the Item: 11
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2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. 3) Schools?
The Project site is within the boundaries of the Saddleback Valley Unified School District (SVUSD). The Project does not propose the development of residential uses; therefore, the Project would not directly result in new students to the SVUSD. The Project is consistent with the General Plan land use designation and zoning for the site. Employment-generating uses have recently occurred within the site and have been anticipated by 2040 General Plan; refer to Section XIV, Population and Housing. Pursuant to Senate Bill (SB) 50, payment of fees to the applicable school district is considered full mitigation for project impacts, including impacts related to the provision of new or physically altered governmental facilities, need for new or physically altered governmental facilities, the construction of which could cause significant environmental impacts, in order to maintain acceptable service ratios, or other performance objectives for schools. The Project Applicant/Developer would be required to pay all statutory fees in place at the time and demonstrate proof of payment to the City. Implementation of SB 50 would ensure impacts to the schools remain less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. 4) Parks?
According to the 2040 General Plan FEIR, the City of Lake Forest maintains approximately 294 acres of public parkland. The Project is consistent with the General Plan land use designation and zoning for the site. Employment-generating uses have recently occurred within the site and have been anticipated by 2040 General Plan. Further, the forecast population growth associated with the Project represents an increase of less than one percent (approximately 0.95 percent) in population over existing conditions and is within the growth projections anticipated by the 2040 General Plan; refer to Section XIV, Population and Housing. Due to the nature of the proposed use (retail warehouse and tire service center) and the relatively small number of new employees, the Project would not induce substantial unplanned population growth within the City that would potentially result in a significant increase in the use of existing parks within the area. The proposed Project would not involve the construction of new park facilities, nor would it result in the need for new or physically altered park facilities. Therefore, the Project would not result in substantial adverse physical impacts associated with the provision of new or physically altered park facilities. Impacts would be less than significant, consistent with the 2040 General Plan FEIR.

Further, the forecast population growth associated with the Project represents an increase of less than one percent (approximately 0.95 percent) in population over existing conditions and is within the growth projections anticipated by the 2040 General Plan; refer to Section XIV, Population and Housing. Due to the nature of the proposed use (retail warehouse and tire service center) and the relatively small number Item: 11
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of new employees, the Project would not induce substantial unplanned population growth within the City that would potentially result in a significant increase in the use of other public facilities within the area.

The proposed Project would not require the provision of new or physically altered libraries or other public facilities and would not result in substantial adverse physical impacts associated with the provision of new or physically altered public facilities. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.

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XVI. Recreation
Would the project:

The potential environmental effects associated with construction and operation of the Project are analyzed within this environmental document and impacts have been determined to be less than significant with compliance with regulatory requirements and implementation of 2040 General Plan policies and actions. The proposed Project would not include recreational facilities or require the construction or expansion of recreational facilities that would have a significant adverse physical effect on the environment.

The 2040 General Plan FEIR determined impacts associated with recreation would be less than significant through the implementation of policies and actions in the 2040 General Plan. As demonstrated above and in Section XV, the proposed Project would also result in less than significant impacts associated with recreation, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.

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XVII. Transportation
Would the project:

Discussion: The 2040 General Plan FEIR determined that impacts to transportation would be less than significant through the implementation of policies and actions in the 2040 General Plan. a) A proposed project would normally have a significant circulation/traffic impact if:
1) The proposed project does not meet any of the screening criteria set forth in the City of Lake Forest Transportation Analysis Guidelines?
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2) The proposed project exceeds the vehicle-miles of travel (VMT) thresholds of significance set forth in the City of Lake Forest Transportation Analysis Guidelines? In July 2020, the City of Lake Forest revised its CEQA Significance Thresholds Guide to remain compliant with State requirements and adopted its own VMT significance thresholds for analyzing transportation impacts under CEQA, consistent with State guidance. The City of Lake Forest Transportation Analysis Guidelines (July 21, 2020) states that for retail projects, a proposed project that does not result in a net increase in total VMT will be considered to have a less-than-significant impact on transportation. Per guidance from City staff, there are two acceptable methodologies for analyzing VMT for retail projects:
either based on VMT per employee or based on the total project VMT accounting. As part of the TIS Technical Memo, a VMT analysis was conducted based on the total project VMT accounting. A summary of the VMT analysis methodology and findings is presented below.

The Project’s impact on regional VMT is comprised of the following components:
• Primary Warehouse Trips consist of vehicle trips made by Costco members to the proposed Project site. In general, the proposed new Costco location would provide an additional option for existing Costco members and would replace existing warehouse trips to the existing nearby Costco locations, resulting in lower average trip lengths for members who choose to shift their existing trip to a more convenient location. Primary trips are expected to either:
o Replace existing warehouse trips to the existing nearby Costco locations; or o Be new warehouse trips made on the transportation network. • Diverted Warehouse Trips include existing trips on nearby roadways on which the motorist decides to drive out-of-direction for a distance to stop at Costco, and when their shopping is concluded, continue on their trip to the ultimate destination. • Employee Trips consist of VMT associated with employees traveling to/from the proposed facility. • Latent Demand at Existing Costco Locations consists of the VMT associated with Costco members making more frequent trips to existing Costco locations due to latent demand that would occur after some members shift to the proposed facility and the existing warehouses become less busy.

As shown in Table 4-31, Change in Regional Total VMT, the Project is estimated to result in a net decrease of 4,737 miles to total regional daily VMT. As such, the Project would not result in a net increase in total VMT and would not exceed the VMT thresholds of significance set forth in the City of Lake Forest Transportation Analysis Guidelines. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.

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Table 4-31
Change in Regional Total VMT
Trip Type Change in Regional Daily VMT
Primary Warehouse Trips -18,738
Shifted from Existing Costco Locations -22,096
New Primary Warehouse Trips +3,358
Diverted Warehouse Trips +1,545
Employee Trips +7,230
Latent Demand at Existing Costco Locations +5,225
All Trips -4,737
Source: Kittelson & Associates, Inc., Focused Transportation Impact Study (TIS) Technical Memorandum, November 26, 2025.
b) Conflict with a program plan, ordinance or policy addressing the circulation system, including transit, roadway, bicycle and pedestrian facilities?
Transit Facilities
Orange County Transportation Authority (OCTA) provides public transportation services within the area of the Project site. In the Project vicinity, bus service is provided along the following routes:
• Route 177 – Laguna Niguel to Mission Viejo via Foothill Ranch Towne Centre • Route 89 – Laguna Beach to Rancho Santa Margarita along El Toro Road • Route 480 – Irvine Metrolink Station to Lake Forest
The Project site would continue to be served by the existing transit system and no modifications to routes or the bus stops within the area would occur as a result of the proposed Project. Further, the Project would not physically alter any roadways that are used by OCTA busses or otherwise interfere with transit facilities. Costco members or employees may utilize existing transit services; however, the Project would not induce substantial unplanned population growth within the City that would potentially exceed existing transit system capacity. The Project would not conflict with a program plan, ordinance or policy addressing the circulation system specific to transit facilities.

Roadway Facilities
The Project site is located within the larger Foothill Ranch Towne Centre. The Project site is accessible via existing driveways along Towne Centre Drive and Market Place, which are accessible via Bake Parkway, Portola Parkway, and Alton Parkway. Regional access to the site is provided via SR-241 to the south/southwest and the I-5 freeway located to the southwest. As part of the Project, the common driveway (i.e., Market Place) that extends from Towne Centre Drive between the Project site and the PetSmart building would be partially reconstructed. The existing four-way stop intersection located along the northern boundary of the Project site would be removed and a new three-way stop intersection would be constructed to the east. Pedestrian walkways and crosswalks would be reconstructed along the common driveway. The existing driveway east of the former movie theater building would also be removed and reconstructed to the east of the proposed Costco Warehouse building. Construction Item: 11
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activities would be temporary. Construction vehicles and equipment would be staged within the Project site and would not result in significant traffic or queuing along Towne Centre Drive or other roadways within the area. As demonstrated in the TIS Technical Memo, Project operations would not increase vehicle queuing at the left-turn and right-turn pockets at any of the studied intersections within the vicinity of the Project site. Although existing roadway facilities will continue to meet the City’s standards, the Applicant will enter into an agreement with the City to assist in furthering initiative SP #02 within the City’s Strategic Business Plan for 2025-2032 to provide for the installation of traffic signal monitoring and operations infrastructure in the Project vicinity. The proposed Project improvements would not involve physical modifications to Towne Centre Drive or other public roadways within the vicinity of the Project site. Existing roadway facilities would continue to serve the Project site and surrounding development.

Four truck loading docks would be located along the southwestern boundary of the proposed warehouse building. Trucks are anticipated to access the loading docks via the Towne Centre Drive/Market Place intersection from Portola Parkway.
26 As discussed in the TIS Technical Memo, the Project would not result in excessive queuing at any of the studied intersections and would maintain acceptable traffic operations at all study intersections. As such, the Project would not conflict with a program plan, ordinance, or policy addressing roadway facilities.

Bicycle Facilities
Lake Forest 2040 General Plan EIR Figure 3.14-3, Existing Bicycle/Pedestrian Facilities, identifies existing bicycle and pedestrian facilities within the City. Class II Bike Lanes are located on Bake Parkway, Alton Parkway, and Portola Parkway within the vicinity of the Project site. Class II Bike Lanes are striped and stenciled lanes for one-way bicycle travel on a street or highway. There are no designated bicycle facilities on Towne Centre Drive or Market Place. The Project does not propose any modifications to roadways within the area that would impact an existing or potential bicycle facility. The Project would not conflict with a program plan, ordinance, or policy addressing bicycle facilities.

Pedestrian Facilities
Sidewalks are currently provided via existing driveways along Towne Centre Drive and Market Place. These driveways connect to common driveways and drive aisles within the interior of the larger Phase 4 area.

As part of the Project, the common driveway (i.e., Market Place) that extends from Towne Centre Drive between the Project site and the PetSmart building would be partially reconstructed. The existing fourway stop intersection located along the northern boundary of the Project site would be removed and a new three-way stop intersection would be constructed to the east. Pedestrian walkways and crosswalks would be reconstructed along the common driveway. The existing driveway east of the former movie theater building would also be removed and reconstructed to the east of the proposed Costco Warehouse building. The Project site would continue to allow for internal pedestrian circulation, similar to existing conditions. The Project would not conflict with a program, plan, ordinance, or policy addressing pedestrian facilities.
26 Delivery trucks would approach from Bake Parkway, turn left onto Portola Parkway, and turn left onto Market Place to access the site via the Towne Centre Drive/Market Place intersection.

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Conclusion
Similar to the conclusions of the 2040 General Plan FEIR, the Project would not conflict with a program plan, ordinance or policy addressing the circulation system, including transit, roadway, bicycle, and pedestrian facilities. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. c) Include design features or uses that may cause traffic hazards such as sharp curves, tight turning radii from streets, limited roadway visibility, short merging lanes, uneven road grades, or any other conditions determined by the City engineer to be a hazard? The Project proposes to demolish a former movie theater building and construct a new retail warehouse building with a tire service center, which would be consistent with the General Plan land use designation and zoning for the site. Thus, the Project would not introduce an incompatible use to the site.

As previously discussed, the Project site is located within the larger Foothill Ranch Towne Centre, which is currently served by local roadways and access driveways. The Project site would continue to be accessed by these existing roadways and driveways. As part of the Project, the common driveway (i.e., Market Place) that extends from Towne Centre Drive between the Project site and the PetSmart building would be partially reconstructed. The existing four-way stop intersection located along the northern boundary of the Project site would be removed and a new three-way stop intersection would be constructed to the east. Pedestrian walkways and crosswalks would be reconstructed along the common driveway. The existing driveway east of the former movie theater building would also be removed and reconstructed to the east of the proposed Costco Warehouse building. Four truck loading docks would be located along the southwestern boundary of the proposed warehouse building. Trucks are anticipated to access the loading docks via the Towne Centre Drive/Market Place intersection from Portola Parkway. As part of the City’s site plan review process, the Project would be reviewed and only approved after finding the proposed development is in conformance with the General Plan and Zoning Code; is compatible with surrounding development; and would not result in conditions or circumstances contrary to the public health and safety and the general welfare. The proposed Project does not include any design features or uses that may cause traffic hazards such as sharp curves, tight turning radii from streets, limited roadway visibility, short merging lanes, uneven road grades, or any other conditions determined by the City engineer to be a hazard. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. d) Result in inadequate emergency access?
The Project site is located within Phase 4 of the Foothill Ranch Towne Centre, an established multi-tenant commercial center located along Towne Centre Drive. Bake Parkway and Alton Parkway provide access to Towne Centre Drive. Alton Parkway provides direct access to SR-241. Construction vehicles and equipment would be staged within the Project site. Construction activities are not anticipated to result in significant traffic or queuing along Towne Centre Drive or other roadways within the area that could potentially impede emergency access.

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Similar to existing conditions, emergency vehicle access to the Project site would be provided via existing driveways along Towne Centre Drive and Market Place. These driveways connect to common driveways and drive aisles within the interior of the larger Phase 4 area. As part of the Project, the common driveway (i.e., Market Place) that extends from Towne Centre Drive between the Project site and the PetSmart building would be partially reconstructed. The existing four-way stop intersection located along the northern boundary of the Project site would be removed and a new three-way stop intersection would be constructed to the east. The existing driveway east of the former movie theater building would also be removed and reconstructed to the east of the proposed Costco Warehouse building. The proposed Project improvements would not involve physical modifications to Towne Centre Drive or other public roadways within the vicinity of the Project site. The proposed improvements within the Foothill Ranch Towne Centre would be required to comply with all applicable design requirements, including the CBC and California Fire Code, as adopted and amended by the City, and would be subject to approval by the City. Therefore, the Project would not result in inadequate emergency access. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.

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XVIII. Tribal Cultural Resources
Significant
Impact
Peculiar to
the Project or
Project site
Impact
Adequately
Addressed in
the General
Plan EIR
Impact
Substantially
Mitigated by
Uniformly
Applicable
Development
Standards
New
Potentially
Significant
Off-Site or
Cumulative
Impact not
Addressed in
the General
Plan EIR
Would the project cause a substantial adverse
change in the significance of a tribal cultural
resource, defined in Public Resources Code
section 21074 as either a site, feature, place,
cultural landscape that is geographically
defined in terms of the size and scope of the
landscape, sacred place, or object with cultural
value to a California Native American tribe,
and that is:
a. Listed or eligible for listing in the California
Register of Historical Resources, or in a
local register of historical resources as
defined in Public Resources Code section
5020.1(k), or
No Yes Yes No
b. A resource determined by the lead agency,
in its discretion and supported by
substantial evidence, to be significant
pursuant to criteria set forth in subdivision
(c) of Public Resources Code Section
5024.1. In applying the criteria set forth in
subdivision (c) of Public Resources Code
Section 5024.1, the lead agency shall
consider the significance of the resource to
a California Native American tribe.

No Yes Yes No
This section is based in part on the Memorandum: Foothill Ranch Preliminary Cultural Resource Desktop Review, Orange County, California (Cultural Resources Report) prepared by Kleinfelder, Inc., dated January 6, 2026, included in its entirety as Appendix B, Cultural Resources Report.

Discussion: The 2040 General Plan FEIR determined that impacts to tribal cultural resources would be less than significant through the implementation of policies and actions in the 2040 General Plan. This topical area is addressed in the 2040 General Plan FEIR Cultural Resources section. a) Would the project cause a substantial adverse change in the significance of a tribal cultural resource, defined in Public Resources Code section 21074 as either a site, feature, place, cultural landscape that is geographically defined in terms of the size and scope of the landscape, sacred place, or object with cultural value to a California Native American tribe, and that is:
1) Listed or eligible for listing in the California Register of Historical Resources, or in a local register of historical resources as defined in Public Resources Code section 5020.1(k)? Item: 11
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2) A resource determined by the lead agency, in its discretion and supported by substantial evidence, to be significant pursuant to criteria set forth in subdivision (c) of Public Resources Code Section 5024.1. In applying the criteria set forth in subdivision (c) of Public Resource Code Section 5024.1, the lead agency shall consider the significance of the resource to a California Native American tribe.

As discussed in Section V, Cultural Resources, the CHRIS records search conducted as part of the Cultural Resources Report indicate that 19 previous cultural studies have been conducted within one-half mile of the Project site, seven of which intersected the Project site. One previously recorded cultural resource was identified within the Project site and 23 cultural resources were identified within a one-half mile radius. A Sacred Lands File (SLF) search was requested from the NAHC with negative results.

Given that the potential for unknown or undiscovered precontact resources to be uncovered through construction activities is not uncommon within the City, the site does not include any peculiar conditions relative to tribal cultural resources. As a standard condition of approval, the Project would be required to comply with 2040 General Plan Action RR-3b, which requires that if construction or grading activities result in the discovery of significant historic or prehistoric archaeological artifacts, all work within 100 feet of the discovery shall cease, the Director of Community Development shall be notified, the resources shall be examined by a qualified archaeologist, paleontologist, or historian for appropriate protection and preservation measures; and work may only resume when appropriate protections are in place and have been approved by the Director of Community Development, reducing potential impacts to less than significant. Additionally, as a condition of approval, archaeological awareness training for Project personnel conducting ground disturbing activities would be conducted by the Project Applicant/Contractor prior to the start of work. Action RR-3b also requires that if human remains are discovered during any ground disturbing activity, work shall stop until the Director of Community Development and the Orange County Coroner have been contacted. If the human remains are determined to be of Native American origin, the NAHC and the MLDs shall be consulted; and work may only resume when appropriate measures have been taken and approved by the Community Development Director.

Therefore, similar to the conclusion in the 2040 General Plan FEIR, implementation of the 2040 General Plan policies and actions, including Action RR-3b, would ensure the Project would not cause a substantial adverse change in the significance of a tribal cultural resource and impacts would be reduced to less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.

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XIX. Utilities and Service Systems
Would the project:

Significant
Impact
Peculiar to
the Project or
Project site
Impact
Adequately
Addressed in
the General
Plan EIR
Impact
Substantially
Mitigated by
Uniformly
Applicable
Development
Standards
New
Potentially
Significant
Off-Site or
Cumulative
Impact not
Addressed in
the General
Plan EIR
a. Require or result in the relocation or
construction of new or expanded water,
wastewater treatment or storm water
drainage, electric power, natural gas, or
telecommunications facilities, the
construction or relocation of which could
cause significant environmental effects?
No Yes No No
b. Have sufficient water supplies available to
serve the project and reasonably
foreseeable future development during
normal, dry and multiple dry years?
No Yes No No
c. Result in a determination by the
wastewater treatment provider which
serves or may serve the project that it has
adequate capacity to serve the project’s
projected demand in addition to the
provider’s existing commitments?
No Yes No No
d. Generate solid waste in excess of State or
local standards, or in excess of the capacity
of local infrastructure, or otherwise impair
the attainment of solid waste reduction
goals?
No Yes Yes No
e. Comply with federal, state, and local
management and reduction statutes and
regulations related to solid waste?
No Yes Yes No
Discussion: The 2040 General Plan FEIR determined that impacts to utilities and service systems would be less than significant through the implementation of policies and actions in the 2040 General Plan. a) Require or result in the relocation or construction of new or expanded water, or wastewater treatment or storm water drainage, electric power, natural gas, or telecommunications facilities, the construction or relocation of which could cause significant environmental effects? Water
The Project site is within the water service area of IRWD. While the existing former movie theater building is not currently operational, the site has historically received water service from IRWD and water infrastructure to serve the site is currently in place. The Project would install domestic water, fire water, and irrigation service lines within the Project site to connect to existing water lines within the site. The Item: 11
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Project would be consistent with the General Plan land use designation and zoning for the site.

Employment-generating uses have recently occurred within the site and have been anticipated by 2040 General Plan; refer to Section XIV, Population and Housing. Therefore, water demand and services associated with the proposed development has been considered in the 2040 General Plan FEIR. Existing water infrastructure and supplies are available within the area to serve the proposed redevelopment of the Project site. The potential environmental effects associated with construction and operation of the Project, including the proposed water infrastructure, are analyzed within this environmental document and impacts have been determined to be less than significant through compliance with regulatory requirements and implementation of 2040 General Plan FEIR policies and actions. Thus, the proposed Project would not require or result in relocation or construction of water facilities, the construction or relocation of which could cause significant environmental effects. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.

Refer to response to XIX(b) below regarding water supply.

Wastewater
In addition to providing water service to the Project site, IRWD provides wastewater service to the Project site. While the existing former movie theater building is not currently operational, the site has historically received wastewater service from IRWD and wastewater infrastructure to serve the site is currently in place. The Project proposes to install a sewer lateral that would connect to the existing sanitary sewer line within the site. The Project would be consistent with the General Plan land use designation and zoning for the site. Employment-generating uses have recently occurred within the site and have been anticipated by 2040 General Plan; refer to Section XIV, Population and Housing. Therefore, wastewater demand and services associated with the proposed development has been considered in the 2040 General Plan FEIR. Existing wastewater infrastructure and treatment capacity are available within the area to serve the proposed redevelopment of the Project site. The potential environmental effects associated with construction and operation of the Project, including the proposed wastewater infrastructure, are analyzed within this environmental document and impacts have been determined to be less than significant through compliance with regulatory requirements and implementation of 2040 General Plan FEIR policies and actions. Thus, the proposed Project would not require or result in relocation or construction of wastewater facilities, the construction or relocation of which could cause significant environmental effects. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.

Refer to response to XIX(c) below, regarding wastewater treatment.

Stormwater
According to the Hydrology Report, the proposed on-site storm drain system would discharge less stormwater than existing conditions and is not expected to cause a negative impact to the downstream systems. The potential environmental effects associated with construction and operation of the Project, including the proposed storm drain improvements to serve the development, are analyzed within this Item: 11
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environmental document and impacts have been determined to be less than significant through compliance with regulatory requirements and implementation of 2040 General Plan FEIR policies and actions. Thus, the proposed Project would not require or result in relocation or construction of stormwater drainage facilities, the construction or relocation of which could cause significant environmental effects. Impacts would be less than significant, consistent with the 2040 General Plan FEIR.

Electricity, Natural Gas, and Telecommunications
The Project site is within the service area of SCE and Southern California Gas Company.

Telecommunication services are provided by a variety of companies and are typically selected by the individual customer. Transmission lines/infrastructure for these services are provided within the Project area and currently serve the Project site and adjacent uses.

The Project’s anticipated electricity demand would be approximately 2,097,813 kWh per year; refer to Section VI, Energy, regarding an analysis of the Project’s energy use. The Project would connect to existing electrical and telecommunications infrastructure. The potential environmental effects associated with the Project’s energy demand are analyzed within this environmental document and impacts have been determined to be less than significant through compliance with regulatory requirements and implementation of 2040 General Plan FEIR policies and actions. The proposed Project would not require or result in relocation or construction of electric power, natural gas, or telecommunications facilities, the construction or relocation of which could cause significant environmental effects. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. b) Have sufficient water supplies available to serve the project and reasonably foreseeable future development during normal, dry and multiple dry years?
IRWD supplies water to the Project site. In order to determine IRWD’s full buildout demands, IRWD coordinates with the cities within its service area on the respective cities’ general planning, which takes into consideration future growth of undeveloped areas. The 2020 UWMP indicates that IRWD will have reserve water supplies (excess of supplies over demands) through 2040 during normal, single-dry, and multiple-dry years. The excess supplies are expected to be available for IRWD to serve as a buffer against variations in demand projections, future changes in land use, or modifications in supply availability. The UWMP water supply predictions are based in part on existing development and General Plan designations for future growth. The Project proposes to demolish a former movie theater building and construct a new retail warehouse building with a tire service center. The Project would be consistent with the General Plan land use designation and zoning for the site. Employment-generating uses have recently occurred within the site and have been anticipated by 2040 General Plan. Further, the forecast population growth associated with the Project represents an increase of less than one percent (approximately 0.95 percent) in population over existing conditions and is within the growth projections anticipated by the 2040 General Plan; refer to Section XIV, Population and Housing. It should also be noted that this population forecast is a conservative assumption and does not take into the consideration the employees of the recently closed movie theater. Therefore, water demand and services associated with the proposed development has been considered in the 2040 General Plan FEIR. Due to the nature of the proposed use (retail warehouse and tire service center) and the relatively small number of new employees, the Project Item: 11
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would not require a significant increase in water demand beyond land uses anticipated for the site.

Further, IRWD’s 2020 UWMP indicates adequate water supplies would be available to serve future water demands during normal, dry, and multiple dry years through 2040, which includes water demand associated with commercial use of the site. Thus, impacts to water supplies would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.
c) Result in a determination by the wastewater treatment provider which serves or may serve the project that it has adequate capacity to serve the project’s projected demand in addition to the provider’s existing commitments?
Wastewater treatment services for the Project site are provided by IRWD. Sewage collected through IRWD’s system is sent to one of the two of IRWD water recycling plants, the Michelson Water Recycling Plant (MWRP) or the Los Alisos Water Recycling Plant (LAWRP). The Project proposes to demolish a former movie theater building and construct a new retail warehouse building with a tire service center. The Project would be consistent with the General Plan land use designation and zoning for the site.

Employment-generating uses have recently occurred within the site and have been anticipated by 2040 General Plan. Further, the forecast population growth associated with the Project represents an increase of less than one percent (approximately 0.95 percent) in population over existing conditions and is within the growth projections anticipated by the 2040 General Plan; refer to Section XIV, Population and Housing.

It should also be noted that this population forecast is a conservative assumption and does not take into the consideration the employees of the recently closed movie theater. Therefore, wastewater demand and services associated with the proposed development has been considered in the 2040 General Plan FEIR. Due to the nature of the proposed use (retail warehouse and tire service center) and the relatively small number of new employees, the Project would not require a significant increase in wastewater demand beyond land uses anticipated for the site. Thus, impacts to water supplies would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.
d) Generate solid waste in excess of State or local standards, or in excess of the capacity of local infrastructure, or otherwise impair the attainment of solid waste reduction goals? The Project proposes to demolish a former movie theater building and construct a new retail warehouse building with a tire service center. The Project would be consistent with the General Plan land use designation and zoning for the site. Employment-generating uses have recently occurred within the site and have been anticipated by 2040 General Plan. Project implementation is anticipated to generate solid waste in amounts similar to existing commercial uses surrounding the Project site. In 2024, approximately 61,229 tons (74.2 percent) of solid waste from Lake Forest was disposed of at the Frank R. Bowerman Sanitary Landfill.
27 The remainder was disposed of at other landfills, including the Olinda Alpha Sanitary 27 California Department of Resources Recycling and Recovery, RDRS Report 2: Jurisdiction Disposal and Beneficial Reuse by Destination,
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Landfill and Prima Deshecha Sanitary Landfill. The Frank R. Bowerman Sanitary Landfill has a maximum permitted throughput of 11,500 tons per day.28 The facility’s maximum permitted capacity is 266,000,000 cubic yards and has a remaining capacity of 160,896,082 cubic yards as of 2023. According to CalEEMod calculations conducted as part of the Air Quality Report, total unmitigated solid waste generation associated with the operation of the Project would be 710 tons per year.29 This would account for less than 0.02 percent of maximum permitted throughput for the Frank R. Bowerman Sanitary Landfill (11,500 tons per day, or 4,197,500 tons per year). Further, this is a conservative assumption and does not account for Project-specific source reduction. Solid waste generated from the Project could be accommodated at the Frank R. Bowerman Sanitary Landfill or a combination of the disposal facilities that currently receive solid waste for disposal from the City. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. e) Comply with federal, state, and local management and reduction statutes and regulations related to solid waste?
CR&R Incorporated (CR&R) provides solid waste and recycling collection services to the City of Lake Forest, including the Project site. Construction and operational activities associated with the Project would generate solid waste requiring disposal by CR&R. Project construction would be required to comply with the California Green Building Standards Code (CALGreen) and Lake Forest Municipal Code Chapter 16.12, Construction and Demolition Debris Diversion, which promotes the recycling of construction and demolition debris to meet the City’s obligations under the California Integrated Waste Management Act of 1989 (AB 939). Projects are required to reuse, recycle, salvage, or divert a minimum percentage or amount of construction and demolition debris in accordance with the requirements of CALGreen. Project operation would also be required to comply with Chapter 16.14, Mandatory Organic Waste Disposal, which addresses organic waste disposal consistent with the Short-lived Climate Pollutant Reduction Act (SB 1383). Compliance with the Lake Forest Municipal Code would ensure the Project’s construction- and operational-related solid waste impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. https://www2.calrecycle.ca.gov/RecyclingDisposalReporting/Reports/JurisdictionDisposalAndBeneficial, accessed December 21, 2025.
28 California Department of Resources Recycling and Recovery, SWIS Facility/Site Activity Details, Frank R.

Bowerman Landfill (30-AB-0360), https://www2.calrecycle.ca.gov/SolidWaste/Site/Summary/2103, accessed December 21, 2025.
29 Detailed CalEEMod output is presented in Appendix A-1 of the Air Quality Report; refer to Appendix A.

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XX. Wildfire
If located in or near state responsibility areas
or lands classified as very high fire hazard
severity zones, would the project:

Significant
Impact
Peculiar to
the Project or
Project site
Impact
Adequately
Addressed in
the General
Plan EIR
Impact
Substantially
Mitigated by
Uniformly
Applicable
Development
Standards
New
Potentially
Significant
Off-Site or
Cumulative
Impact not
Addressed in
the General
Plan EIR
a. Substantially impair an adopted emergency
response plan or emergency evacuation
plan?
No Yes No No
b. Due to slope, prevailing winds, and other
factors, exacerbate wildfire risks, and
thereby expose project occupants to,
pollutant concentrations from a wildfire or
the uncontrolled spread of a wildfire?
No Yes No No
c. Require the installation or maintenance of
associated infrastructure (such as roads,
fuel breaks, emergency water sources,
power lines or other utilities) that may
exacerbate fire risk or that may result in
temporary or ongoing impacts to the
environment?
No Yes No No
d. Expose people or structures to significant
risks, including downslope or downstream
flooding or landslides, as a result of runoff,
post-fire slope instability, or drainage
changes?
No Yes No No
Discussion: The 2040 General Plan FEIR determined that impacts to wildfire would be less than significant through the implementation of policies and actions in the 2040 General Plan. a) Substantially impair an adopted emergency response plan or emergency evacuation plan? The area surrounding the Project site is generally urbanized and developed with roadways and commercial uses. According to CAL FIRE, the Project is located within a LRA and is not identified as being within a VHFHSZ.30 Thus, the Project site and surrounding area are not identified as having a significant risk associated with wildfire. While the Project site is not located within an SRA or lands classified as VHFHSZ, a VHFHSZ within an LRA is located approximately 0.5 miles northwest of the site.

The Project proposes to demolish a former movie theater building and construct a new retail warehouse building with a tire service center. The proposed Project would be consistent with the General Plan land 30 California Department of Forestry and Fire Protection, Find your Fire Hazard Severity Zone (FHSZ), https://osfm.fire.ca.gov/what-we-do/community-wildfire-preparedness-and-mitigation/fire-hazard-severity-zones, accessed December 14, 2025.

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use and zoning for site and would not introduce new occupants or structures to a previously undeveloped site. Compliance with the Lake Forest Municipal Code would further reduce potential impacts related to wildland fire, including Chapter 8.24, California Fire Code, adopts the California Fire Code, with amendments. The 2040 General Plan also includes policies and actions to reduce potential impacts due to wildfires, including but not limited to, Action PS-2d which directs the City to participate in Mutual Aid Agreements with neighboring cities and the Orange County Operational Area.

During Project construction, construction vehicles and equipment would be staged within the Project site.

Construction activities are not anticipated to result in significant traffic or queuing along Towne Centre Drive or other roadways within the area that could potentially impede emergency vehicles or impair any emergency evacuation plan.

Similar to existing conditions, emergency vehicle access to the Project site would be provided via existing driveways along Towne Centre Drive and Market Place. These driveways connect to common driveways and drive aisles within the interior of the larger Phase 4 area. As part of the Project, the common driveway (i.e., Market Place) that extends from Towne Centre Drive between the Project site and the PetSmart building would be partially reconstructed. The existing four-way stop intersection located along the northern boundary of the Project site would be removed and a new three-way stop intersection would be constructed to the east. The existing driveway east of the former movie theater building would also be removed and reconstructed to the east of the proposed Costco Warehouse building. The proposed Project improvements would not involve physical modifications to Towne Centre Drive or other public roadways within the vicinity of the Project site. The proposed improvements within the Foothill Ranch Towne Centre would be required to comply with all applicable design requirements, including the CBC and California Fire Code, as adopted and amended by the City, and would be subject to approval by the City. As such, construction and operation of the proposed Project would not impair an adopted emergency response plan or emergency evacuation plan. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. b) Due to slope, prevailing winds, and other factors, exacerbate wildfire risks, and thereby expose project occupants to, pollutant concentrations from a wildfire or the uncontrolled spread of a wildfire?
As discussed above, the Project site is not located within an SRA and is not located within a VHFHSZ within an LRA. A VHFHSZ within an LRA is located approximately 0.5 miles northwest of the site. The area surrounding the Project site is generally urbanized and developed with roadways and commercial uses.

The Project would be required to comply with the Lake Forest Municipal Code and policies and actions in the 2040 General Plan. Project construction and operation would not exacerbate wildfire risks and thereby expose project occupants to pollutant concentrations from a wildfire or the uncontrolled spread of a wildfire beyond existing conditions. Impacts would be less than significant, consistent with the 2040 General Plan FEIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.

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c) Require the installation or maintenance of associated infrastructure (such as roads, fuel breaks, emergency water sources, power lines or other utilities) that may exacerbate fire risk or that may result in temporary or ongoing impacts to the environment? The Project site is located within an urbanized area, surrounded by existing development, and associated infrastructure. The Project would not require the installation or maintenance of infrastructure that may exacerbate fire risk or result in temporary or ongoing impacts to the environment. The Project would be required to comply with the Lake Forest Municipal Code and policies and actions in the 2040 General Plan.

Similar to the conclusions of the 2040 General Plan FEIR, the proposed Project would result in less than significant impacts associated with wildfire risks due to installation or maintenance of associated infrastructure. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met. d) Expose people or structures to significant risks, including downslope or downstream flooding or landslides, as a result of runoff, post-fire slope instability, or drainage changes? As discussed in Section VII, Geology and Soils, the Geotechnical Study concludes that the risk from landslides and other forms of mass wasting is considered low due to the lack of significant slopes at the site. Further, as demonstrated in Section X, Hydrology and Water Quality, the Project site is not located within a 100-year FEMA flood zone and runoff from the Project would not exceed the capacity of the downstream storm drain system. The Project would not expose people or structures to significant risk associated with wildfires, including flooding or landslides as a result of runoff, post-fire slope instability, or drainage changes. The Project would be required to comply with the Lake Forest Municipal Code and policies and actions of the 2040 General Plan, which would reduce potential wildfire impactsto a less than significant level, consistent with the General Plan EIR. Accordingly, impacts under this criterion were adequately addressed in the 2040 General Plan FEIR. No impacts peculiar to the Project or the Project site have been identified. Thus, pursuant to CEQA Guidelines Section 15183, the criteria for requiring further CEQA review are not met.

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REFERENCES
Acoustical Engineering Services, Inc., Environmental Noise Impact Study, Costco Wholesale Warehouse Project Foothill Ranch, California, January 2026.

California Air Resources Board, Final 2022 Scoping Plan Update and Appendices, December 2022, https://ww2.arb.ca.gov/our-work/programs/ab-32-climate-change-scoping-plan/2022-scopingplan-documents, accessed December 23, 2025.

California Department of Conservation, California Important Farmland Finder, https://maps.conservation.ca.gov/DLRP/CIFF/ accessed December 12, 2025.

California Department of Finance, E-5 Population and Housing Estimates for Cities, Counties, and the State, 2020-2025, May 2025.

California Department of Forestry and Fire Protection, Find your Fire Hazard Severity Zone (FHSZ), https://osfm.fire.ca.gov/what-we-do/community-wildfire-preparedness-and-mitigation/firehazard-severity-zones, accessed December 14, 2025.

California Department of Resources Recycling and Recovery, RDRS Report 2: Jurisdiction Disposal and Beneficial Reuse by Destination,
https://www2.calrecycle.ca.gov/RecyclingDisposalReporting/Reports/JurisdictionDisposalAndBe neficial, accessed December 21, 2025.

California Department of Resources Recycling and Recovery, SWIS Facility/Site Activity Details, Frank R.

Bowerman Landfill (30-AB-0360),
https://www2.calrecycle.ca.gov/SolidWaste/Site/Summary/2103, accessed December 21, 2025.

California Department of Toxic Substances Control, EnviroStor, https://www.envirostor.dtsc.ca.gov/public/map/?global_id=71002656, accessed December 14, 2025.

California Department of Transportation, California State Scenic Highway System Map, https://caltrans.maps.arcgis.com/apps/webappviewer/index.html?id=465dfd3d807c46cc8e805 7116f1aacaa, accessed December 15, 2025.

California Department of Water Resources, Division of Safety of Dams, Dam Breach Inundation Map Web Publisher, https://fmds.water.ca.gov/webgis/?appid=dam_prototype_v2, accessed December 18, 2025.

California Environmental Protection Agency, Cortese List Data Resources, https://calepa.ca.gov/sitecleanup/corteselist/, accessed December 14, 2025.

City of Lake Forest, Appendix A: City Of Lake Forest CEQA Significance Thresholds Guide, November 20, 2001 (revised May 6, 2025).

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Federal Emergency Management Agency, Flood Insurance Rate Map, Map Number 06059C0316J, December 3, 2009.

Foothill Ranch Company, Foothill Ranch Planned Community Development Plan and Supplemental Text, April 1988.

Irvine Ranch Water District, 2020 Urban Water Management Plan, June 2021.

Kimley-Horn and Associates, Inc., Preliminary Hydrology & Hydraulics Report for SDP 05-25-5800 Costco Foothill Ranch, November 2025.

Kimley-Horn and Associates, Inc., Santa Ana Region Priority Project Preliminary Water Quality Management Plan (PWQMP), Costco Foothill Ranch 26602 Towne Centre Drive, Foothill Ranch, CA May 18, 2025 (Revised November 3, 2025).

Kittelson & Associates, Inc., Focused Transportation Impact Study (TIS) Technical Memorandum, November 26, 2025, updated January 21, 2026.

Kleinfelder, Inc., Memorandum: Foothill Ranch Preliminary Cultural Resource Desktop Review, Orange County, California, January 6, 2026.

Kleinfelder, Inc., Geotechnical Study (Revised) Proposed Costco Wholesale Warehouse 26602 Towne Centre Drive Foothill Ranch, California, April 4, 2025 (Revised November 21, 2025).

Orange County Water District (OCWD), Basin 8-1 Alternative 2022 Update, January 2022.

Ramboll Americas Engineering Solutions, Inc., Foothill Ranch Costco Project Air Quality Technical Report, December 2025.

Ramboll Americas Engineering Solutions, Inc., Foothill Ranch Costco Project Energy Technical Report, December 2025.

Ramboll Americas Engineering Solutions, Inc., Foothill Ranch Costco Project Greenhouse Gas Emissions Technical Report, December 2025.

State Water Quality Control Board, 2024 Integrated Report, https://gispublic.waterboards.ca.gov/portal/apps/webappviewer/index.html?id=f0e4ac76fd0e4 a53bebead89339ef3c9, accessed December 19, 2025.

State Water Resources Control Board, GeoTracker, https://geotracker.waterboards.ca.gov/search, accessed December 14, 2025.

United States Geological Survey, Lateral Spread, https://www.usgs.gov/media/images/lateral-spread, accessed December 12, 2025.

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REPORT PREPARATION PERSONNEL
City of Lake Forest (Lead Agency)
100 Civic Center Drive
Lake Forest, California 92630
949-461-3491
Connor Musler, AICP, Associate Planner
De Novo Planning Group (Environmental Consultant)
180 East Main Street, Suite 108
Tustin, California 92780
949-396-8193
Starla Barker, AICP, Principal Planner
Tin Cheung, Principal Scientist
Josh Smith, AICP, Senior Planner
Erik Anderson, AICP, Associate Planner
Technical Specialists
Ramboll Americas Engineering Solutions, Inc. (Air Quality, Energy, GHG Report) 2211 Michelson Drive, Suite 400
Irvine, California 92612
Kleinfelder, Inc. (Geotechnical Study and Cultural Resources Report) 24411 Ridge Route Drive, Suite 225
Laguna Hills, California
Kimley-Horn and Associates, Inc. (Hydrology Report and WQMP) 1100 Town and Country Road, Suite 700
Orange, CA 92868
Acoustical Engineering Services, Inc. (Noise Impact Study) 515 South Flower Street, 18th Floor
Los Angeles, CA 90071
Kittelson & Associates, Inc. (TIS Technical Memo)
750 The City Drive, Suite 410
Orange, CA 92868
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PC Attachment 5.2
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Costco Wholesale Project
CEQA Guidelines 15183 | Environmental Compliance Checklist Appendix A
Appendix A – Air Quality Report

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DRAFT
Prepared for
Costco Wholesale Corporation
Prepared by
Ramboll Americas Engineering Solutions, Inc.

Irvine, California
Project Number
1940111785
Date
December 2025
Ramboll Americas Engineering Solutions, Inc.
2211 Michelson Drive
Suite 400
Irvine, California 92612
(949) 261-5151

FOOTHILL RANCH COSTCO PROJECT

AIR QUALITY TECHNICAL REPORT

LAKE FOREST, CALIFORNIA
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DRAFT Foothill Ranch Costco Project
Air Quality Technical Report
Lake Forest, California
i
Contents Ramboll

CONTENTS
Page

1. INTRODUCTION 1

1.1 Existing Conditions 1

1.2 Proposed Project 1

2. ENVIRONMENTAL AND REGULATORY BACKGROUND 2

2.1 Criteria Air Pollutants 2

2.1.1 Ozone 2

2.1.2 Nitrogen Dioxide 2

2.1.3 Carbon Monoxide 2

2.1.4 Sulfur Dioxide 3

2.1.5 Particulate Matter 3

2.1.6 Lead 3

2.1.7 Sulfates 4

2.1.8 Vinyl Chloride 4

2.1.9 Hydrogen Sulfide 4

2.1.10 Visibility-Reducing Particles 4

2.2 Non-Criteria Air Pollutants 4

2.2.1 Toxic Air Contaminants 4

2.2.2 Diesel Particulate Matter 5

2.3 Regulatory Setting 5

2.3.1 Federal and State Ambient Air Quality Standards for Criteria Air Pollutants 5

2.3.2 Federal Regulations and Policies 6

2.3.3 State Regulations and Policies 10

2.3.4 Local Regulations and Guidance 16

2.4 Environmental Setting 20

2.4.1 Local Air Quality Monitoring Data 20

3. SIGNIFICANCE THRESHOLDS 21

3.1 California Environmental Quality Act Guidelines 21

3.2 South Coast Air Quality Management District Thresholds 21

3.3 Project Approach to Significance 22

4. AIR QUALITY EMISSIONS INVENTORY 23

4.1 Resources 23

4.1.1 California Emission Estimator Model 23

4.1.2 Other Resources 24

4.2 Construction Emissions 24

4.2.1 Emissions from Construction Equipment 25

4.2.2 Emissions from On-Road Construction Trips 26

4.2.3 Fugitive Dust 26

4.2.4 Architectural Coating 27

4.2.5 Paving 27

4.2.6 Total Construction Emissions 27

Lake Forest City CouncilMarch 17, 2026

Lake Forest City Council
March 17, 2026