San Diego Region - Underground Storage Tank Cleanup Oversight Program

Program Goals

The goals of the Underground Storage Tank (UST) Cleanup Oversight program is to protect human health, safety and the environment by overseeing the investigation and cleanup of unauthorized releases of petroleum and other hazardous substances from underground storage tanks.

Program Description

California has been regulating underground storage tanks (USTs) containing hazardous substances since 1983, applying federal and state laws, regulations and policies. The State Water Resources Control Board (SWRCB) is the designated lead regulatory agency for the development of UST regulations and policy. The three primary elements of the UST Cleanup Oversight Program are prevention, cleanup oversight, and cleanup reimbursement. The Regional Board's Tank Site Mitigation & Cleanup (TSMC) Unit provides technical and regulatory oversight for the investigation and cleanup of sites impacted by leaking USTs, and develops local guidance on implementing the policies and procedures of the SWRCB. Along with the three county local oversight program agencies in the San Diego Region, TSMC Unit staff documents and tracks the process of cleaning up all known UST releases within our region. This information is maintained in the GeoTracker data warehouse. For information on GeoTracker, please visit the State Water Resources Control Board Division of Clean Water Programs, Leaking Underground Storage Tank Information System Website. This Website will provide information, tutorials, and a direct link to GeoTracker. You may access GeoTracker directly at

Guidance and Policy Documents

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  • LNAPL Guidance - Regional Board Supplemental Instructions and Interim Guidance on Required Cleanup at Low-Risk Fuel Contaminated Sites: Appendix A - Guidance on Data Collection Requirements for the Evaluation of Residual Free Product or Light Non-Aqueous Phase Liquid (LNAPL) on Groundwater. (Dated July 1998)
  • Sensitive Aquifer Guidance - "Information on the New Maps Depicting RWQCB Hydrologic Basins & Sensitive Aquifer Areas" (Dated June 13, 1996)
  • Underground Storage Tank Case Closure Summary Form (Dated October 1995)
  • Nonpurge Method Guidance - Use of Nonpurge Method for Sampling of Groundwater Monitoring Wells at Gasoline Impacted Sites (RWQCB, dated June 20, 1997 )
  • MTBE Sampling Requirement - Mandatory MTBE Sampling for Underground Storage Tank (UST) Site Closures-Senate Bill (SB) 521 (RWQCB, dated February 20, 1998)
  • MTBE Detection Method Guidance - Guidance on Using USEPA Method 826013 for Detection of Methyl Tertiary-Butyl Ether (MTBE) (SWRCB, dated August 20, 1999)
  • Additional Sampling for Fuel Oxygenates - Because of growing concern about other oxygenates we now request that you add the other ether oxygenates [diisopropyl ether (DIPE), tertiary amyl methyl ether (TAME), and ethyl tertiary butyl ether (ETBE)] as well as tertiary butyl alcohol (TBA) to the list of gasoline components to be monitored

For More Information

Please contact Mr. Sean McClain at 619-521-3374 or by email at