Second Addendum to the Building 200 Replacement Initial Study / Negative Declaration

Second Addendum to the Building 200 Replacement Initial Study / Negative Declaration

The Building 200 Replacement project entails the replacement of a one-story, 10,650-square-foot (sf) building (Building 200) located in the southeastern corner of its North Base in the City of South San Francisco, San Mateo County, California. The New Building 200 will be a 19,800-sf building, providing additional space for management offices, operator amenities, bus operations, meeting space, and support spaces. Although the location of the New Building 200 will change as described and analyzed in this Second Addendum, the size of the new building will not change. Since completion of the First Addendum in 2025, the District has determined that, to maintain SamTrans operations and minimize service disruptions for local riders, the project scope must be revised. Under the First Addendum, the District planned to construct a Temporary Building 200 and permanent Building 800 and would then demolish the Existing Building 200. The New Building 800 would include building utility and mechanical equipment and could easily be switched from the Temporary Building 200 to the New Building 200 when construction was completed. To simplify this process and to minimize the disruption of SamTrans service, as analyzed in this Second Addendum, the District will construct the New Building 200 approximately 65 feet south of the Existing Building 200 before demolishing the Existing Building 200. This approach will allow SamTrans to maintain operations throughout construction without the use of temporary facilities or a separate utility building. Therefore, the project will no longer include the construction and demolition of the Temporary Building 200, nor construction of Building 800 described in the First Addendum. The New Building 200 will be the same size as the New Building 200 that was analyzed in the 2024 IS-ND and the First Addendum. In addition, the District has determined that construction staging, laydown, or temporary parking lot may be required outside of the existing boundaries of North Base. If necessary, such activities may extend into the adjacent vacant parcel (Assessor Parcel 015180200) directly east of North Base. These activities will occur within an approximately 33,226-square-foot area (0.76 acres) located more than 100 feet from the shoreline of Belle Aire Island. The District will obtain a temporary construction easement for such activities. No other substantial changes to the Building 200 Replacement project will occur.

San Mateo

San Francisco Bay Area

San Mateo