The Washington Department of Ecology’s recent amendments to the state contaminated site cleanup regulations under the Model Toxics Control Act (MTCA) require screening to determine whether contaminated sites may affect “vulnerable populations” or “overburdened communities” at different stages of the cleanup process.¹ In January 2024, Ecology released high-level methodological guidance, Implementation Memorandum No. 25: Identifying Likely Vulnerable Populations and Overburdened Communities under the Cleanup Regulations, on how to make these initial determinations.

Ecology will use information about potential impacts on vulnerable populations or overburdened communities for strategic planning and agency resource allocation. This information will also be considered during site-specific investigations and remedial action decisions. Ecology will track sites with potential impacts to these populations and communities in the Site Hazard Assessment and Ranking Process Tool.

The new guidance specifies that, as a starting point, the “potentially exposed population” will be assumed to include a “likely vulnerable population or overburdened community” if the population is located in a census tract with certain demographic criteria contained in the Environmental Health Disparities Index from the Washington State Department of Health’s EHD Map or the Demographic Index from the U.S. Environmental Protection Agency's EJScreen. The guidance also provides for the use of “site-specific information” to refine both the potentially exposed populations and their demographics. Reflecting the limitations and assumptions inherent in the screening methods, Ecology has also required certain confidence levels in the data necessary to integrate these determinations into the agency’s strategic planning and site-specific cleanup decisions.

While the guidance clarifies certain aspects of new environmental justice provisions in the state cleanup regulations, it is incremental, leaving many key issues unaddressed. It does not explain, for example, how these determinations will be considered during site cleanups and does not identify what site-specific information Ecology will consider appropriate for refining census tract-level screening assessments or how such information should be collected or analyzed. Additional guidance is likely necessary to minimize uncertainty surrounding the implementation of the new environmental justice requirements under MTCA.

With an office in Seattle, WA, Beveridge & Diamond’s Superfund, Site Remediation, and Natural Resources Damages practice group assists clients in litigation and allocation of CERCLA sites, including complex, large-scale sites. We counsel clients on developing case law and requirements under CERCLA and state-equivalent hazardous waste laws. The Firm’s Environmental Justice practice also has been at the forefront of EJ issues for decades, bringing specialized private sector and government experience to bear. We represent multinational companies and municipal clients in complex disputes and high-profile project development, corporate ethics and governance, environmental compliance, and investigations related to EJ and Title VI of the Civil Rights Act of 1964 enforcement. For more information, please contact the authors.

¹ These terms are defined in the Healthy Environment for All (HEAL) Act, and incorporated by reference in the MTCA regulations. The HEAL Act was passed by the state legislature in 2021 to address environmental and health disparities among communities of color and low income households.