September 25, 2023

Amendments to MTCA Cleanup Regulation will Strengthen and Simplify Environmental Cleanup in Washington


On August 23, 2023, the Washington Department of Ecology (“Ecology”) adopted amendments to Model Toxics Control Act (“MTCA”) cleanup regulations contained in Washington Administrative Code (“WAC”) Chapter 173-340 (“Amendments”). MTCA is the Washington state equivalent of the Comprehensive Environmental Response Cleanup and Liability Act (“CERCLA”) or Superfund, which imposes strict, joint and several liability on certain categories of people to clean up contaminated sites. Ecology is the agency responsible for implementing and administering MTCA. These amendments are  the first of numerous rulemakings that Ecology plans to roll out to update MTCA cleanup regulations.[1]

These Amendments, designed to “update and clarify many of the administrative and procedural requirements for cleaning up contaminated sites,” will go into effect on January 1, 2024. The major themes focused on for this round of amendments were:

  • Environmental justice;
  • Public participation and tribal engagement;
  • Site hazard assessment and ranking;
  • Planning and prioritizing MTCA resources;
  • Site level decisions & procedures;
  • Independent vs. Ecology cleanups; and
  • Underground storage tank release response

The Amendments may impact persons who:

  • Are responsible for investigating and cleaning up contaminated sites;
  • Provide services to those who investigate and clean up contaminated sites;
  • Own or operate underground storage tanks; and
  • May be exposed to or impacted by contaminated sites

With respect to environmental justice, a remedial investigation must now include information on threats to likely vulnerable populations and overburdened communities in consideration of land use and human receptors. The word “likely” now appears before every instance of the phrase “vulnerable populations,” which reduces the evidentiary burden on Ecology of showing that a population is vulnerable.

The most significant amendment to the public participation and tribal engagement section of the regulations requires that Ecology initiate and maintain meaningful engagement with affected tribes before Ecology initiates a remedial investigation or interim action at a site. The Amendments also requires Ecology to make public on its website the date of discovery or notice of a release.

The  Amendments also implement a new way to assess the risk of contaminated sites using the Site Hazard Assessment and Ranking Process (“SHARP”), an interactive tool that guides users through a series of questions and then calculates a score on the potential contamination exposure and its severity in soil, groundwater, surface water, sediment, and indoor air. The SHARP tool will also utilize a confidence rating that takes into account how much is known about a site. Environmental justice considerations are  built in the SHARP tool by utilizing indicators on the individual community from other agencies such as environmental exposures, environmental effects, sensitive populations, and socioeconomic factors. Overall, site scoring resulting from use of the SHARP tool will allow Ecology to compare sites.

In the category of simplification for Ecology-conducted or supervised remedial actions, Ecology will now allow a cleanup action plan to contain an estimated mass or estimated volume of hazardous substances remaining on site, rather than specify the amounts of hazardous substances remaining on site.  This should make remedial actions easier to reach completion.

The Amendments will require  that independent remedial actions must now include the performance of  a feasibility study, and  identify the administrative differences between an independent remedial action and a remedial action conducted or supervised by Ecology.

Within the remedial investigation and remedy selection, the  Amendments introduce step-by- step procedures for remedial investigations and feasibility studies. Reporting requirements are clarified, as are how public concerns and tribal rights and interests are to be considered and documented. A cleanup action must provide resilience to climate change impacts that have a high likelihood of occurring, which must be considered in conducting the analysis of cleanup alternatives.

Finally, the  Amendments address releases from regulated underground storage tanks by accelerating investigation and cleanup of such releases. For example, at sites that complete a remedial action within 90 days of release, the release will need to be reported separately within 90 days of the release, rather than after the remedial action has been completed. In addition, the Amendments require that free product must begin to be removed within 30 days after discovery, with quarterly monitoring and progress reports required.

Jordan Ramis can assist with guidance around compliance with these regulatory amendments and will continue to update clients as Ecology continues to roll out changes to MTCA regulations.



Tags: Environmental and Natural Resources

Back to Top