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Updating the underground storage tank regulations

We propose repealing existing Chapter 173-360 WAC and adopting new Chapter 173-360A WAC, Underground Storage Tank (UST) regulations. The new chapter would replace the repealed chapter and change the existing regulations. The regulations are intended to prevent the release of petroleum or other hazardous substances from UST systems, and ensure that any release is detected and cleaned up.

Washington currently has a federally-approved UST compliance program. This means that state law, not federal law, applies to regulated UST systems in the state (except for those on Native American lands).

Under state law, we regulate more than 9,000 UST systems at more than 3,300 facilities, including gas stations, industries, commercial properties, and governmental entities. We work to ensure that UST systems are installed, managed, and monitored in a manner that prevents releases into the environment. To do so, we inspect over 1,300 facilities each year and provide technical assistance to owners and operators.

Learn more about the UST program.

Why we are updating the UST regulations

In October 2015, the Environmental Protection Agency (EPA) adopted changes to the rules governing the federal UST program (40 Code of Federal Regulations [CFR] Part 280) and state program approval (40 CFR Part 281). These are the first major changes to the federal rules since 1988.

The changes enact the requirements in the UST Compliance Act of 2005, add new operation and maintenance requirements for UST systems, and establish requirements for certain types of UST systems that were deferred in 1988. States with federally-approved programs must incorporate the changes by October 2018 to maintain program approval.

Learn more about changes to federal requirements.

Subject and scope of rulemaking

We propose repealing existing Chapter 173-360 WAC and adopting new Chapter 173-360A WAC, Underground Storage Tank (UST) Regulations.  The new chapter would replace the repealed chapter and change the existing regulations.   As part of the rulemaking, we propose to:

  • Incorporate federal rule changes needed to continue the UST program, as specified in 40 C.F.R. Parts 280 and 281 and adopted in June 2015.
  • Incorporate changes to the state’s UST program specified in the authorizing state statute, Chapter 90.76 RCW.
  • Make other selective changes to the requirements governing the state’s UST program (such as updating UST service provider requirements).
  • Streamline rule requirements, improve rule clarity, and improve consistency within the rule and with other state and federal laws and rules.

The rulemaking may impact people who:

  • Own or operate UST systems.
  • Provide services to owners and operators.
  • ​Deliver product to, or collect waste oil from, UST systems.
  • Provide pollution liability insurance for UST systems.
  • Conduct training for operators of UST systems.
Learn more about our rulemaking.