Underground Storage Tanks (UST)

Program Description

The Central Coast Water Board's underground storage tank (UST) Cleanup Unit provides technical and regulatory oversight for the investigation and cleanup of sites with leaks from USTs. Leaking USTs are a significant threat to groundwater and pose potential threat to human health, safety, and the environment. Therefore, California has been regulating USTs containing hazardous substances since 1983, applying federal and state laws, regulations and policies. The State Water Resources Control Board (State Board) is the designated lead regulatory agency for the development of the UST Program, regulations, and policy. In development of the UST Program, four main program elements have been identified: leak prevention program; tank integrity testing; enforcement of requirements; and cleanup of leaking tanks. Various agencies contribute and have jurisdiction over the UST program elements, including the Certified Unified Program Agencies (CUPAs), which are the implementing agencies for the leak prevention program element. A CUPA is a local agency that has been certified by Cal EPA to implement the six state environmental programs, which include the Hazardous Materials Business Plan/Emergency Response Plan, Hazardous Waste/Tiered Permitting, Underground Storage Tanks, Aboveground Storage Tanks (SPCC only), California Accidental Release Program and the Uniform Fire Code Hazardous Materials Management Plan, within the local agency's jurisdiction. The State Board administers the Tank Tester Licensing Program to meet the tank integrity testing requirements, which are required by law. Enforcement of UST requirements is primarily conducted by the local agencies, although the Water Boards and State Board do provide assistance. The cleanup element of the program involves investigation and remediation of leaking underground tanks, under the direction of local implementing agencies and/or Water Boards.

In addition, the GeoTracker data warehouse and geographic information system (GIS) provides online access to environmental data. It is used to plot UST site and monitoring well locations and track regulatory information about UST facilities, Spills, Leaks, Investigations, and Cleanup (SLIC) sites, and public drinking water wells, and in the future will include other types of cleanup and investigation sites, including Department of Defense (DoD), Landfill, and Aboveground Storage Tank facilities. GeoTracker uses commercially available software to allow users, including the public, to access data over the Internet. Case information can be graphically displayed as a layer on GeoTracker, includes highways and roads, topographic maps, surface water boundaries, watershed boundaries, groundwater basins, and hydrologic vulnerability areas by entering a site address, partial site address, or site name.

Finally, the UST Cleanup Fund is an independent but related State Board program.

Low-Threat Closure Policy

On May 1, 2012, the State Water Board adopted a Low-Threat Underground Storage Tank (UST) Case Closure Policy (Policy). See State Water Board Resolution No. 2012-0016. The Policy was approved by the Office of Administrative Law (OAL) on July 30, 2012. On August 17, 2012, the Notice of Decision was filed with the California Secretary for Natural Resources, and the Policy became effective

Go to the State Water Board website for the Low-Threat Closure Policy

An evaluation of the data must be completed under the adopted State Water Resources Control Board (SWRCB) Low-Threat Underground Storage Tank Case Closure Policy (LTCP). In order to facilitate our review of the LTCP we need the following information.

  1. Please submit a draft case summary form for the subject site.
  2. Pursuant to the California Health and Safety Code, Section 25296.20, and Porter Cologne Water Quality Control Act, Section 13307.1, the Central Coast Water Board is required to notify all current fee titleholders of sites impacted by releases from the underground storage tanks on your facility prior to case closure. Please submit a complete mailing list of all record fee titleholders for the subject site and surrounding properties within a 200 foot radius.
  3. Please submit a scaled map showing all water well (domestic, agricultural, industrial, etc.) locations within a ½ mile of the site. Please include a table indicating the well name, well number, well owner, date of installation, well use, well status, distance from site, well depth, and screen intervals.

Below are the links of the documents required to review the LTCP:

Addition of Materials for In-Situ Bioremediation, Chemical Oxidation, Chemical Reduction, or Tracer Test

NEW! Injection of materials to the substrate is an effective treatment technology used to reduce the levels of contaminants in the soil and/or groundwater at active groundwater cleanup sites.  A discharger must seek coverage under the adopted General Waiver of Waste Discharge Requirement for Specific Types of Discharge, Resolution Order No. R3-2019-0089 Attachment A, Section B.

Discharge of Treated Groundwater

The discharges of highly treated groundwater resulting from cleanup at leaking underground storage sites and spill sites requires a General Permit.  An application for the National Pollutant Discharge Elimination System Permit for Discharge of Highly Treated Groundwater to Surface Waters, Order No. R3-2006-0067, NPDES No. CAG993002 is located in the Adopted Orders Section.


The Central Coast Water Board (Water Board) is the State regulatory agency responsible for protecting the quality of groundwater and surface waters within its region. Through State laws/regulations the Water Board has authority to require submission of information, direct action, establish regulations, levy penalties and bring legal action when necessary to protect water quality. Pursuant to the Porter-Cologne Water Quality Control Act (California Water Code, Division 7), Section 13267, the Water Board may require investigation of the quality of any waters of the State within its region and, in doing so, may require the submittal of necessary technical reports. Furthermore, California Water Code Section 13304 provides that the Water Board may require cleanup of waste and abate the effects of a discharge or a threat of a discharge of waste into the waters of the State.

The UST Program's authority comes from the California Health & Safety Code, which gives local agencies the authority to oversee investigation and cleanup of UST leak sites. Some local agencies provide oversight for underground fuel storage tank cases through the County Local Oversight Program (LOP) contract with the State Board.

For more information, please contact Greg Bishop of the Underground Storage Tank Cleanup Unit at (805) 549-3132 or by email at greg.bishop@waterboards.ca.gov.