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Toxics Cleanup Program

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Overview of Program

Washington State has a federally-approved Underground Storage Tank (UST) program.  This means that state law, not federal law, applies to UST systems in this state.

Under state law, the Department of Ecology (Ecology) currently regulates more than 9,200 tanks at more than 3,400 facilities, including gas stations, industries, commercial properties, and governmental entities.  Ecology works to ensure these tanks are installed, managed, and monitored in a manner that prevents releases into the environment.  To do so, Ecology conducts compliance inspections at about 1,200 facilities each year, and provides technical assistance to tank owners.

Changes to UST Regulations (click to show/hide)   

On August 8, 2012, the Department of Ecology (Ecology) adopted changes to Chapter 173-360 WAC, Underground Storage Tank Regulations. The changes will be published in the Washington State Register on September 5, 2012, and become effective on October 1, 2012.  The changes:

  • Authorize Ecology to stop regulated substances from being delivered to UST systems that do not comply with regulatory requirements.

  • Establish an operator training program for individuals who operate and maintain UST systems.  Current operators must be trained by December 31, 2012.

  • Require emergency response signage at all UST facilities.

  • Require secondary containment and interstitial monitoring of tanks and pipes installed or replaced after October 1, 2012.

  • Require containment under dispenser systems if the dispenser, dispenser system, or underground piping connected to the dispenser system is installed or replaced after October 1, 2012.

To learn more about the changes please visit the adopted rules webpage for details and copies.

Compliance with Operator Training Requirements  (click to show/hide)   

Under the adopted rule amendments, operators must be trained by December 31, 2012.  Visit our operator training webpage to learn more about operator training requirements and training opportunities.

Underground Storage Tank Compliance Act of 2005  (click to show/hide)   

In 2005, Congress passed the Energy Policy Act.  Title XV, Subtitle B of this act (titled the Underground Storage Tank Compliance Act) contains amendments to Subtitle I of the Solid Waste Disposal Act, the original legislation that created the federal UST program.  The Act requires state UST programs receiving federal funding to comply with new federal requirements, including:

  • Conducting more frequent compliance inspections.

  • Implementing a delivery prohibition process.

  • Developing an operator training program.

  • Requiring secondary containment for new or replaced tanks and pipes.

  • Requiring containment under new or replaced dispenser systems.

  • Providing reports to EPA and the public (see below).

To learn more about the federal requirements, see
Information on the sources and causes of UST releases in Washington State for Federal Fiscal Year 2014 (October 1, 2013 to September 30, 2014).

* Always check with your local environmental authority as they may have regulations for activities regarding USTs, Oil Water Separator Maintenance and Rules.

Page last revised May 6, 2015

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