Santa Ana UST

Underground Storage Tank (UST) Program


The Santa Ana Regional Water Quality Control Board’s (Santa Ana Water Board’s) UST and Site Cleanup Program Section (UST/SCP Section) directs environmental cleanup activities at leaking petroleum UST sites located within the Santa Ana Region. These sites include active and inactive gasoline stations, brownfield redevelopment sites, airports, bulk petrochemical storage terminals, pipeline facilities, and various industrial facilities.

Leaking petroleum USTs are a significant threat to groundwater and pose a potential threat to human health, safety, and the environment. California has been regulating USTs containing hazardous substances since 1983 by applying federal and state laws, regulations, and policies to achieve cleanup standards. The State Water Resources Control Board (State Water Board) is the designated lead regulatory agency for the development of the petroleum UST Program, regulations, and policy. The four main petroleum UST Program elements developed by the State Water Board include: leak prevention program; tank integrity testing; enforcement of requirements; and cleanup of leaking tanks.

Various agencies are involved with implementing the petroleum 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 the California Environmental Protection Agency 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, California Accidental Release Program, and the Uniform Fire Code Hazardous Materials Management Plan, within the local agency's jurisdiction. For more information on CUPAs please see the Quick Links.

The State Water Board administers the Tank Tester Licensing Program to meet the tank integrity testing requirements, which are required by law. Enforcement of petroleum UST permitting, testing, and leak prevention requirements is primarily conducted by the local agencies, although the State Water Board may also provide enforcement assistance to local agencies. The cleanup element of the petroleum UST Program includes the investigation and remediation of petroleum releases from leaking petroleum USTs under the oversight of the Regional Water Boards and State Water Board Certified Local Oversight Programs (LOPs).


The Santa Ana 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 Santa Ana 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 Santa Ana 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 Santa Ana 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.

California Health & Safety Code (Division 20, Chapter 6.7) gives local agencies the authority to oversee investigation and cleanup of leaking petroleum UST sites. Assessment and cleanup of leaking petroleum USTs is governed by the California Water Code, Division 7, and Title 23, Division 3, Chapter 16 of the California Code of Regulations. Within the Santa Ana Region, the leaking petroleum UST Cleanup Program is implemented under the direction of the Santa Ana Water Board and the State Water Board Certified Orange County LOP. Contact information for the Orange County LOP can be found by clicking on the following link for Certified LOPs and additional information is provided in the Quick Links.

GeoTracker Database

Information on leaking UST Cleanup Program sites can be found using the State Water Board’s data management system – GeoTracker. For online access to environmental data for UST cleanup sites, click the following link to access GeoTracker.

Low-Threat Closure Policy

On May 1, 2012, the State Water Board adopted a Low-Threat Underground Storage Tank Case Closure Policy (LTCP); see State Water Board Resolution No. 2012-0016. The LTCP was approved by the Office of Administrative Law on July 30, 2012. On August 17, 2012, the LTCP went into effect when a Notice of Decision for the Policy was filed with the California Secretary for Natural Resources. Additional information is provided in the Quick Links.

This LTCP is a statewide policy which applies to all leaking petroleum UST sites subject to Chapter 6.7 of Division 20 of the California Health and Safety Code and Title 23, Division 3, Chapter 16 of the California Code of Regulations. The LTCP establishes consistent, statewide case closure criteria for low-threat petroleum UST sites. The LTCP establishes both general and media-specific standardized criteria for closure that ensures the protection of human health, safety, and the environment. If both the general and applicable media-specific criteria are satisfied, then the case is typically considered to present a low threat to human health, safety, and the environment and can be considered for closure under the LTCP.

Pursuant to the California Health and Safety Code, Section 25296.20, and Porter Cologne Water Quality Control Act, Section 13307.1, the Santa Ana Water Board is required to notify all current fee titleholders of sites impacted by releases from the petroleum USTs on a facility when a case is being considered for closure. Santa Ana Water Board staff typically notify the recorded fee titleholders for the subject site and surrounding properties within a 200-foot radius of the facility. Santa Ana Water Board staff review and respond to comments received during the 60-day notification and public comment period. If no comments are received, and additional corrective actions are not required, then a directive is issued to abandon or destroy case-related monitoring wells and remediation equipment must be removed from the site. After the completion of these activities a no further action (NFA) letter consistent with California Health and Safety Code section 25296.10 can be issued.

For information on leaking petroleum UST Cleanup Program cases which are proposed for closure or have recently received closure under the LTCP, please click on the following link to the UST Cleanup Case Proposed Closures webpage.

Additional Information

In-Situ Remediation or Tracer Test

Injection of materials to the subsurface can be an effective treatment technology used to reduce the levels of contaminants in the soil and/or groundwater at active groundwater cleanup sites. Before implementing this type of remediation, a discharger must first have a remedial action plan, which has been reviewed and approved by the lead oversight agency, then seek coverage under the adopted General Waste Discharge Requirements for In-Situ Groundwater Remediation at Sites within the Santa Ana Region, Order No. R8-2018-0092. For more information on Waste Discharge Requirements (WDRs) please click on the following link to the State Water Board Waste Discharge Requirements Program.

Discharge of Treated Groundwater

The discharges of highly treated groundwater resulting from cleanup at leaking petroleum UST sites requires a permit consistent with National Pollutant Discharge Elimination System (NPDES) Program and California Waste Discharge Requirements. To obtain an individual permit or coverage under the General Groundwater Cleanup Permit for Discharges to Surface Waters of Extracted and Treated Groundwater Resulting from the Cleanup of Groundwater Polluted by Petroleum Hydrocarbons and/or Solvents, Order No. R8-2012-0027, NPDES No. CAG918001, an application and report of waste discharge must be submitted for review by Santa Ana Water Board staff. For more information please click on the following link to the State Water Board NPDES Program webpage. You may also click the following link for a list of contacts in the Santa Ana Water Board’s Wastewater Section.

Case File Reviews

For inquiries regarding documents or files for current or closed UST Program cases not available in the GeoTracker database, please click the following link for more information on Public Records Requests, or submit a request by email to:







For general questions regarding the UST Program please contact: