UST Program – LG 113

Welcome to the online home of Local Guidance (LG) Letter 113, the “List of Leak Detection Equipment and Methods for Underground Storage Tanks.”

California Code of Regulations, Title 23, Chapter 16, section 2643(f) requires underground storage tank (UST) leak detection equipment and methods to be evaluated by an independent third-party testing organization. The evaluation must demonstrate that the equipment/method can detect leaks at a specified threshold greater than 95 percent of the time, and that the probability of false alarms is less than 5 percent. The evaluation must also be conducted in accordance with accepted protocols or consensus standards.

To assist local agencies in reviewing and approving monitoring plans, the State Water Resources Control Board (SWRCB) has published updated versions of LG 113 since December 13, 1990. The list includes only equipment/methods that have had their independent evaluations reviewed and listed by the “National Work Group on Leak Detection Evaluations” (hereafter referred to as “Work Group”). The Work Group is comprised of 10 members: 8 of which represent various states and 2 from the United States Environmental Protection Agency. Their primary goal is the creation of a list of leak detection products that have undergone third-party evaluations adhering to specified engineering criteria.

Publication of LG 113 should eliminate the need for local agencies to review third-party evaluations of equipment/methods for compliance with state and federal requirements. However, it has inherent limitations. It is based on one-time evaluations, often conducted in a lab setting according to protocols that do not test all aspects of the equipment. Therefore, appearance in LG 113 does not mean that the equipment will work or comply with regulations at every site. Get additional information on the Work Group.

LG 113 Resources

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