PUBLIC NOTICE Former Naval Station Treasure Island, San Francisco, CA Notice of Five-Year Review Installation Restoration Sites 6, 12, 21, 24, 27, and 30 August 2025 The United States Department of the Navy (Navy), as the lead agency, has completed the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Five-Year Review (5YR) for environmental cleanup activities at the former Naval Station Treasure Island (NSTI) in San Francisco, California. The NSTI is located in the San Francisco Bay between the City of San Francisco and Oakland. CERCLA requires a review every five years for remedies where contamination remains above levels that allow for unlimited use and unrestricted exposure. The Navy conducted the 5YR in accordance with the requirements of CERCLA Section 121(c) to evaluate the effectiveness of the remedies outlined in the Records of Decision (RODs) and to ensure the remedies continue to be protective of human health and the environment. The Navy conducted a 5YR of the remedies implemented at NSTI for Installation Restoration (IR) Sites 6, 12, 21, 24, 27, and 30. The remedies at these IR Sites were implemented to address chemicals of concern in soil, sediment, soil gas, and/or groundwater that pose potentially unacceptable risk to human health and the environment. The remedies include soil removal, groundwater treatment and/or monitoring, soil vapor extraction and monitoring, and land use controls. The 5YR report provides an update on the status of remedial actions since the previous 5YR (2020) and documents progress on recommendations made in the previous 5YR. IR Sites 6, 21, 27, and 30 were determined to be protective. IR Sites 12 and 24 were determined protective in the short term and the review provided recommended actions to ensure they will be protective in the long term. FOR MORE INFORMATION The Final CERCLA 5YR Report is available for public inspection at the following website and location: https://administrative-records.navfac.navy.mil/?RV367W236GMWQ74JG4WQ Administrative Record Diane Silva, NARA Certified Command Records Manager NAVFAC Southwest 750 Pacific Highway, Code EV33 NBSD Bldg. 3519 San Diego, CA 92132-5190 Phone: (619) 556-1280 E-Mail: diane.c.silva.civ@us.navy.mil 8/27/25 CNS- #