An underground storage tank (UST) is defined by law as "any one or combination
of tanks, including pipes connected thereto, that is used for the storage of
hazardous substances and that is substantially or totally beneath the surface
of the ground" (certain exceptions apply).
The purpose of the UST Program is to protect public health and safety and
the environment from releases of petroleum and other hazardous substances from
tanks. There are four program elements:
The Leak Prevention Program element includes requirements for tank
installation, construction, testing, leak detection, spill containment, and
overfill protection. Certified Unified Program Agencies
are the implementing agencies for the Leak Prevention program element. To find out which Unified Program Agency is responsible for your facility, see the Unified Program Regulator Directory.
Cleanup of leaking tanks often involves a soil and groundwater
investigation and remediation, under the direction of a regulatory
agency. Responsible parties (RPs) who believe cleanup at their site
is complete and are denied case closure by the regulatory
agency, may consider filing a closure
The State Water Resources Control Board provides assistance to local agencies
enforcing UST requirements.
Tank Tester Licensing
Tank integrity testing is required by law, must meet the requirements of the
State Water Resources Control Board, and must be conducted by State licensed
Proposed Closure of Underground Storage Tank Cases