EPA is Seeking Comment on Potential Designations of Additional PFAS as Hazardous Substances Under CERCLA

The Advance Notice of Proposed Rulemaking ("ANPRM") addresses seven per- and polyfluoroalkyl substances ("PFAS"), including PFBS and GenX.

On April 13, 2023, the Environmental Protection Agency ("EPA") published an ANPRM in the Federal Register requesting public input and data to assist in the potential development of future regulations of PFAS under the Comprehensive Environmental Response, Compensation, and Liability Act ("CERCLA"), also known as Superfund. EPA is considering the designation of the following PFAS as hazardous substances under section 102(a) of CERCLA: 

  • Perfluorobutanesulfonic acid (PFBS);
  • Perfluorohexanesulfonic acid (PFHxS);
  • Perfluorononanoic acid (PFNA);
  • Hexafluoropropylene oxide dimer acid (HFPO–DA, but often referred to as GenX);
  • Perfluorobutanoic acid (PFBA);
  • Perfluorohexanoic acid (PFHxA); and
  • Perfluorodecanoic acid (PFDA). 

EPA is also considering and seeking input on whether to initiate a future action to designate precursors to these seven PFAS, as well as precursors to perfluorooctanoic acid ("PFOA") and perfluorooctane sulfonic acid  ("PFOS"), as CERCLA hazardous substances, and whether to designate entire groups or categories of PFAS as CERCLA hazardous substances. 

Designating some or all of these chemicals as CERCLA hazardous substances would trigger new release reporting requirements and give EPA expanded authority to require investigation and remediation of releases of these chemicals in the environment. Such a development could create significant new risks for companies with potential environmental cleanup liabilities at sites affected by PFAS. 

The ANPRM follows EPA's Notice of Proposed Rulemaking in September 2022 designating PFOA and PFOS as CERCLA hazardous substances. EPA is in the process of reviewing comments on the September 2022 proposal. In that proposal, EPA had forecasted its intent to initiate future rulemaking to designate additional PFAS as CERCLA hazardous substances. 

This notice signals a continued regulatory focus on PFAS, as outlined in EPA's PFAS Strategic Roadmap. Like the proposed designation of PFOA and PFOS as CERCLA hazardous substances in September, the actions being considered in this ANPRM could have significant impacts on Superfund liability. 

The comment period will be open until June 12, 2023. 

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