Two PFAS Compounds Designated Hazardous Substances Under CERCLA

Last week the U.S. Environmental Protection Agency (EPA) finalized a new rule designating perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) as hazardous substances under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA). This rule gives the EPA broad power to require investigation and remediation at current and closed Superfund sites and can potentially lead to designation of new Superfund sites. Here is a summary of several key implications of this new rule.

How could active Superfund sites be affected?

With this rule the EPA may now modify response actions at any stage of the CERCLA process. For sites at which remedial investigations, risk assessments, and feasibility studies are in progress or complete, EPA may require new sampling and investigation to determine if PFOA or PFOS are present. At sites for which a Record of Decision, remedial design, remedial action construction, or remedial action operation are in progress or complete, EPA may require a modification to the Record of Decision, modification or new remedial design, and modification or new remedial actions to address PFOA and PFOS.

At sites for which Remedy Complete has been achieved, EPA may require new sampling to assess PFOA and PFOS, and possibly return the site to any earlier stage if PFOA and PFOS are deemed to be contaminants of concern and a remedy is required. Each of these possibilities can result in significant schedule delays, added investigation and reporting costs, and added remedial action costs to address PFOA and PFOS. This may also result in significant renegotiations or litigation costs between responsible parties over allocation of costs related to PFOA and PFOS.

How could closed Superfund sites be affected?

EPA may order new investigations for the presence of PFOA and PFOS even at closed sites. Based upon the outcome of those investigations, EPA may elect to require new or further investigations, risk assessments, and remedial actions. These can be conducted with or without formally reopening Superfund sites. Thus, responsible parties may incur significant additional legal and site investigation and remedial action costs, even long after the site was considered finished.

Could the rule lead to designation of new Superfund sites?

Yes. EPA may require site assessments where PFOA or PFOS discharges are known or suspected. EPA may also require inclusion of PFOA and PFOS sampling at sites where other types of contaminant discharges are known or suspected. Depending upon the outcome of those assessments, a site may be selected for further work, potentially including a listing on the National Priorities List, and proceed with the CERCLA process. Thus, sites may become Superfund sites solely because of the presence of PFOA or PFOS, or PFOA and PFOS may be identified as additional contaminants of concern at other sites beginning the CERCLA process.

How could public or municipal facilities be affected?

One of the contentious aspects of listing PFOA and PFOS as hazardous substances under CERCLA is that many locations where PFOA or PFOS were never directly used may become PRPs at Superfund sites. One example of this is publicly owned treatment works (POTWs). POTWs may have received PFOA and PFOS from users of their system that discharged the compounds as part of their waste streams. POTWs are not typically capable nor designed to address PFOA or PFOS. Treated wastewater discharged by a POTW or biosolids spread at a farm may result in release of PFOA or PFOS and potentially subject the POTW to Superfund liabilities.

While EPA has indicated that it may utilize enforcement discretion to limit the potential liability of POTWs, the POTWs may still be held liable under lawsuits filed by other parties that do incur investigation or remediation costs. Carveouts for POTWs and other entities have been proposed in bills before Congress, but as of now, no legislation has been passed to limit such potential liabilities.

What other, related actions might EPA take?

EPA has proposed several additional actions related to PFOA, PFOS, and other PFAS, in addition to today’s action and the April 10, 2024, announcement of Federal drinking water standards for PFOA, PFOS, and four other PFAS. In April 2023, the EPA requested information from the public relevant to whether seven additional PFAS (PFBS, PFHxS, PFNA, HFPO-DA [GenX], PFBA, PFHxA, and PFDA) may present substantial risk to public health or welfare or the environment, and thus also potentially justify listing as Hazardous Substances under CERLCA. In February 2024, EPA proposed including PFOA, PFOS, and seven other PFAS (PFBS, HFPO-DA [GenX], PFNA, PFHxS, PFDA, PFHxA, and PFBA) as hazardous constituents under the Resource Conservation and Recovery Act (RCRA). This would provide EPA the power to require investigations, risk assessments, and remedial measures at approximately 1,740 RCRA facilities across the United States, like the authority granted by today’s listing to the EPA for CERCLA sites.

How can Woodard & Curran help?

Woodard & Curran offers a full range of services and a deep bench of experts to assist our clients in navigating the maze of federal regulations efficiently and cost effectively. Our experts take a science-based approach to site investigation, risk assessment, and creative remedial design, with continuous optimization to ensure remedies meet design and cost objectives. We further support our clients with regulatory compliance, risk management and communication, air monitoring and transport modeling, public and industrial wastewater treatment, and drinking water resource management, supply, and treatment services. Our team offers small-company service with big-company resources.


Dan Bryant Practice Leader Emerging Contaminants

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