EPA Tackles Hazardous Substance Designation for Multiple PFAS

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November 10, 2021

A hazardous substance designation for PFAS would impact ongoing remediation projects and reporting requirements

On October 18, 2021, the U.S. Environmental Protection Agency (EPA) issued the PFAS Strategic Roadmap, detailing a number of actions EPA will take on per- and polyfluoroalkyl substances (PFAS) between 2021 and 2024, including developing a Notice of Proposed Rulemaking to designate perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) as hazardous substances under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). EPA anticipates publishing a proposed rule in the spring of 2022 and a final rule by summer 2023. EPA will also consider designating additional PFAS chemicals as hazardous substances once analytical methods to measure these chemicals in groundwater and specific information about their health effects are developed.

A hazardous substance designation for PFOA and PFOS — and potentially other PFAS such as perfluorobutane sulfonic acid (PFBS) and GenX — has important implications. Parties who dispose of or release CERCLA hazardous substances in the environment are potentially jointly and severally liable under CERCLA. Currently, no PFAS compounds are designated as hazardous substances, and, therefore, PFAS do not currently trigger CERCLA liability. Hazardous substance designations would require facilities to report releases of PFOA and PFOS and allow federal, tribal, and state authorities to obtain information regarding the location and extent of releases.


At current CERCLA sites, designation of selected PFAS as hazardous substances could delay remediation as additional assessments are conducted and remedial plans reassessed.


Efforts to allocate costs may need to be modified as the number of potentially responsible parties increases and sources of PFAS are investigated. The designation will likely trigger establishment of new CERCLA sites and lead to reopening and possible additional responses at some existing CERCLA sites when PFAS is considered during required five-year reviews.

CERCLA designation will also complicate ongoing PFAS remediation managed under other regulatory frameworks if a site ultimately is listed under CERCLA. Many states have remediation programs that incorporate federal hazardous substances lists, so the reach of EPA's action will extend beyond CERCLA sites. While suits alleging natural resources damages (NRD) associated with PFAS releases have already been filed, hazardous substances designation will make CERCLA's NRD process available to trustees. Overall, CERCLA designation is expected to lead to new or substantially increased environmental and tort liabilities for many entities and to protracted legal battles.

While the CERCLA designation process is ongoing, EPA is initiating actions under existing environmental laws — including the Resource Conservation and Recovery Act (RCRA), the Toxic Substances Control Act (TSCA), and the Clean Water Act (CWA) — to investigate PFAS releases at existing facilities and increase enforcement. A week after the Roadmap's release, EPA announced plans to evaluate adding PFOA, PFOS, PFBS, and GenX to the list of RCRA Hazardous Constituents.

How Exponent Can Help

Exponent's consultants have the expertise to help clients navigate the rapidly evolving PFAS scientific and regulatory landscape. Our multidisciplinary team of analytical, forensic, and polymer chemists; engineers; and health scientists can help you assess the presence and potential risks and liabilities associated with PFAS at your facility. Our experts can also critically evaluate new regulations in order to clarify requirements, limit uncertainty, and develop solutions for our client's needs. Exponent's scientists and engineers assist clients with selecting appropriate methods and laboratories for PFAS analyses, as well as with PFAS source identification, chemical fingerprinting, environment fate and transport analyses, and cost allocation.