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Bombshell: PFOA and PFOS Designated as CERCLA Hazardous Substances

April 19, 2024
4 minute read

Bombshell: PFOA and PFOS Designated as CERCLA Hazardous Substances

April 19, 2024
4 minute read

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EPA Designates PFOA and PFOS as Hazardous Substances

In a long-awaited action, on April 19, 2024, the United States Environmental Protection Agency (EPA) has designated the two most studied per- and polyfluoroalkyl substances (PFAS) – perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), including their salts and structural isomers—as hazardous substances under the federal Comprehensive Environmental Response, Compensation and Liability Act (CERCLA), also known as the “Superfund” law. For “state lead” cleanup programs, such as Wisconsin, this federal rule development represents one of the strongest enforcement tools available for compelling action to address PFAS in the environment.

The effective date of this federal rule is to be 60 days after publication in the federal register, anticipated in June 2024, absent any legal challenge.

The impact of regulating PFOA and PFOS under CERCLA will be wide-reaching. For one, the Wisconsin DNR may refer entities recalcitrant to perform cleanups including PFAS in Wisconsin to EPA Superfund program (EPA Region 5) for enforcement under CERCLA.  This process is contemplated by the Memorandum of Agreement between the Wisconsin Department of Natural Resources (DNR) and EPA, known as the One Cleanup Program.

In recognition of the broad impact of this rule, EPA released a concurrent “PFAS Enforcement Discretion and Settlement Policy Under CERCLA” Memorandum the same day, April 19, 2024. In the Enforcement Discretion Policy Memo, EPA states it does “not intend to pursue otherwise potentially responsible parties [PRPs] where equitable factors do not support seeking response actions or costs. . .”  The PRPs named as entities to receive enforcement discretion are municipal and publicly owned and operated passive receptors of PFAS (e.g., Publicly Owned Treatment Works, municipal landfill operators, and drinking water systems) and farmers where biosolids are applied to their land. This enforcement discretion is similar to Wisconsin DNR policies for prioritizing the pursuit of entities that cause environmental contamination under the Spills Law.

Liability under CERCLA differs slightly from Wisconsin’s cleanup laws. Entities liable for costs or performance of a cleanup of a hazardous substance under CERCLA, according to section 107(a), include (1) current owners and operators where hazardous substances are present; (2) past owners and operators at the time of disposal; (3) generators and third-party arrangers for disposal or transport of hazardous substances; and (4) transports of hazardous waste to the site.

EPA Establishes Enforceable Drinking Water Standards for 6 PFAS

In another long-awaited development, EPA promulgated the first National Primary Drinking Water regulation to address PFAS at levels far lower than Wisconsin’s current Maximum Contaminant Level (MCL) for PFOA and PFOS.  In Wisconsin, public water supplies are required to meet 70 parts per trillion (ppt) for PFOA and PFOS.

EPA sets the applicable standard at 4 ppt for PFOA and PFOS and establishes 10 ppt for three common PFAS: PFHxS, GenX Chemicals, and PFNA. The rule also proposes a novel Hazard Index method  for determining compliance for mixtures of PFHxS, GenX Chemicals, PFNA and PFBS.  The Hazard Index only applies for any mixture containing two or more of these four PFAS.

While this national drinking water rule was published in April 2024, there is a delayed compliance deadline where monitoring of public water systems must occur by April 2027, and compliance achieved by April 2029. This runway will allow for enough time for promulgation of lengthy state rulemaking processes in states such as Wisconsin.

Wisconsin rulemaking is necessary to update the MCLs. According to Wis. Stat. ch. 160, Wisconsin drinking water regulations cannot be more lax than federal standards. Wisconsin DNR will likely avoid the landmine of the Economic Impact Statement requirement in Wisconsin rulemaking under Wis. Stat. ch. 227 for establishing and updating drinking water standards for PFOA, PFOS, GenX chemicals, PFHxS, PFNA and PFBS due to this federal rule.  If DNR begins rulemaking by July 2024, Wisconsin will have an effective drinking water rule in compliance with these federal standards on or by the April 2027 compliance deadline.

Godfrey & Kahn has been tracking and advising clients regarding notable PFAS developments, including two massive PFAS settlements that manufacturers of PFAS have agreed to with a class of plaintiffs comprised of municipalities and other utilities that provide drinking water to customers.

Wisconsin DOJ Appeals Wisconsin Hazardous Substance Decision SCOWIS

Significant PFAS developments in April 2024 were not limited to federal actions by EPA. 

The Wisconsin Department of Justice filed a petition for review with the Supreme Court of Wisconsin on April 5, 2024, appealing an appellate court decision concerning whether PFAS are “hazardous substances” under Wisconsin law or whether rulemaking is first required to apply the statutory definition to chemicals such as PFAS.

The case involves a commercial dry-cleaning company that discovered PFAS as part of a site investigation under Wisconsin’s Voluntary Party Liability Exemption program .  If accepted by the Supreme Court of Wisconsin for argument, the decision will have significant impact on Wisconsin environmental rulemaking requirements, not only for the state cleanup program or for regulations pertaining to PFAS.

If you’d like further information about PFAS, best practices for evaluating potential liability and proactive management of these issues, please contact Ned Witte or Bill Nelson at Godfrey & Kahn.

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