The Washington Department of Ecology (“Ecology”) has updated its rules implementing the Model Toxics Control Act (MTCA), the first substantial update in over 20 years. MTCA governs the investigation and cleanup of sites contaminated by hazardous substances in Washington State. The rules set the cleanup standards and other requirements for carrying out MTCA objectives. The new rules were adopted on August 23, 2023 and will go into effect on January 1, 2024.

The rule revisions may impact you if you:

• Are responsible for investigating and cleaning up contaminated sites
• Provide services to persons who investigate and clean up contaminated sites
• Own or operate UST systems regulated under Chapter 173-360A WAC
• May have been exposed to or impacted by contaminated sites

While the framework of the rules remains the same, the updates contain material changes that will impact the course of cleanups in the state. Key updates cover:

• Initial Investigations: Ecology is no longer required in all circumstances to inspect the site before determining if there has been a release or threatened release of a hazardous substance to the environment. If sufficient information has already been reported, Ecology does not need to collect additional information to make a determination. Ecology can collect additional information without visiting the site and can rely on other government agencies to collect information. The rules clarify that Ecology can request that others, such as owners or operators, collect information about the site. These changes reflect current practice and have the potential to speed up initial investigations and reduce investigation costs.
• SHARP to replace WARM: MTCA requires Ecology to develop a hazard ranking system. Previously, Ecology ranked sites using the Washington Ranking Method (WARM) specified in the existing rules; it will now conduct rankings through a site hazard assessment and ranking process (SHARP). The SHARP tool scores exposure potential and severity to rank sites for cleanup priority, and it allows for a site’s ranking to be updated based on new information. Ecology believes SHARP will be more efficient, flexible, and easier to use and will start publishing SHARP results once the revised rules are adopted in 2024.
• Remedial Investigations: Some revisions to the remedial investigation section of the rules will increase both time and cost for cleanups. The new rule clarifies that a remedial investigation should be conducted at all contaminated sites, regardless of which investigation option—Ecology-conducted, Ecology-supervised, or independent—is used to conduct remedial action at the site. Additionally, Ecology removed the Ecology-approved list of sampling and analysis methods from the rules, giving it more discretion to approve such methods. The list of approved sampling and analysis will now be housed outside of the rules on Ecology’s website.
• Reporting Requirements: The revised rules expand the class of parties and the type of actions that require reporting. Owners and operators are now required to report a threatened release of hazardous substance to Ecology within 90 days of discovery. Unfortunately, the rules do not define “threatened” release; however, Ecology acknowledges that further clarity may be needed and may provide further guidance in its Toxics Cleanup Program Policy about what constitutes a threatened release and when it poses a threat requiring remedial action.
  
  Several rule changes were made regarding what needs to be reported and the timing of said reporting. For example, independent investigations must now be reported to Ecology within 90 days of completion (completion means if no remedial action other than compliance monitoring has occurred at the site for 90 days). Since the existing rules contained no such requirement, there are many sites for which Ecology has limited information—even though one or more independent site investigations may have been conducted over the years by property owners, prospective purchasers, or others. Because environmental consultants already report those results to their clients, Ecology does not expect the new reporting requirement to be a significant burden.
• Environmental Justice Considerations: Environmental justice concerns are now directly addressed by the rule revisions. For example, an initial investigation now requires a determination of “[w]hether the population that may be threatened includes a likely vulnerable population or overburdened community.” Vulnerable populations can include indigenous people, immigrant and refugees, and the houseless. Additional environmental justice considerations include requirements for cultural preservation.
• Cleanup Standards: While many changes were made throughout the rules, the rulemaking did not change cleanup standards—the levels at which a particular hazardous substance is considered to not threaten human health or the environment. Revisions to Part 7 of the rules were done only to address corrections identified by practitioners and to conform with changes to other parts of the rules.

Additional information and insight into the rulemaking process can be found here, in Ecology’s Concise Explanatory Statement for the rulemaking. Ecology will next prepare updates to its Toxic Cleanup Program Policies to provide guidance on implementing the new rules.