2024 has already been a banner year for the regulation of per- and polyfluoroalkyl substances (PFAS) at the federal level; unsurprisingly, these efforts are eliciting legal challenges from regulated entities.

CERCLA

On April 19, 2024, the EPA issued a final rule under Section 102(a) of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). The rule, which became effective on July 8, 2024, designates two types of PFAS—perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), including their salts and structural isomers—as hazardous substances. According to the final rule, PFOA and PFOS are characterized by their persistence in the environment and tendency to bioaccumulate in living things.

PFAS are found in nearly all environments and many products due to their unique properties that enable them to endure extreme temperatures, resist degradation, stains, and grease, and provide nonstick properties. Widely entering commercial production in the 1940s, these chemicals can often be found in lubricants, water-repellent clothing, and non-stick kitchenware. PFAS have also been used in firefighting foams, generating thousands of lawsuits which were combined into a multi-district litigation.

The final rule cites evidence that exposure to PFOA and PFOS can lead to adverse health impacts including cancer (testicular and kidney), cardiovascular disease, pregnancy-induced hypertension and preeclampsia, and decreased immune response to vaccination. EPA stated that by listing these chemicals as hazardous substances, it aims to “address more sites, take earlier action, and expedite eventual cleanup” of sites contaminated with these compounds.

This hazardous substance designation imposes strict reporting requirements under CERCLA Sections 103 and 111(g) and Section 304 of the Emergency Planning and Community Right-to-Know Act (EPCRA). Facility or vessel operations must report any release of one pound or more of PFOA or PFOS within a 24-hour period to the National Response Center (NRC) and other relevant agencies. Additionally, owners or operators of vessels or facilities must provide reasonable notice to potential injured parties of any releases.

The designation of these PFAS compounds as hazardous substances has significant implications for environmental liability. This could lead to the inclusion on the National Priorities List (NPL) of sites primarily contaminated with PFOA and PFOS, such as fire training facilities, military bases, or airports, thus imposing retroactive liability on their owners and operators. The listing might also lead to more comprehensive remedial actions at affected sites. Additionally, generators of PFAS-contaminated waste may face liability for cleanups at facilities managing multiple contaminants, such as landfills.

The hazardous substances-designation also has implications for environmental due diligence in real estate transactions. The potential for releases of PFOA and PFOS must now be considered in complying with the EPA’s All Appropriate Inquiries (AAI) standard to benefit from the bona fide prospective purchaser defense to CERCLA liability for the current owner of a facility.

Following the announcement of the rule, EPA released a memorandum outlining the agency’s PFAS Enforcement Discretion and Settlement Policy under CERCLA. The policy indicates that in identifying Potentially Responsible Parties (PRPs), EPA will primarily target PFAS manufacturers, parties who used PFAS in their manufacturing processes, and other industrial users. EPA stated that it will rely on CERCLA statutory protections and its existing enforcement discretion polices to alleviate stakeholder concerns that the designation could lead to PFAS liability under CERCLA, when equitable considerations support the exercise of such discretion. EPA states its intent to exercise enforcement discretion in consideration of whether an entity is a government body, performs essential public services, or is actively involved in the use and disposal of PFAS. The agency does not intend to pursue enforcement actions against community water systems and publicly owned treatment works, municipal separate storm sewer systems (MS4s), publicly owned municipal solid waste landfills, publicly owned airports and local fire departments, nor farms where biosolids are applied to the land. The memorandum indicates that EPA may also work with such stakeholders to help protect them from potential third-party liability, for example through “de micromis” settlements that will provide contribution protection under CERCLA Section 113(f)(2), 42 U.S.C. § 113(f)(2).

The U.S. Chamber of Commerce, the Associated General Contractors of America, and the National Waste & Recycling Association have filed a petition in the D.C. Circuit Court of Appeals challenging the rule pursuant to CERCLA Section 113(a), 42 U.S.C. § 9613(a). The industry challengers argue that the new rule may lead to prolonged and counterproductive litigation. The groups also expressed concerns over what they believe is a lack of clear standards for determining hazardous substances under CERCLA, which could create uncertainty for local governments, landowners, and businesses.

Safe Drinking Water Act

On April 10, 2024, the EPA issued the first final National Primary Drinking Water Regulations (NPDWRs) establishing Maximum Contaminant Levels (MCLs) for six PFAS compounds, including PFOA and PFOS, under the Safe Drinking Water Act (SDWA). EPA set the Maximum Contaminant Level Goal (MCLG, a non-enforceable health-based goal) for PFOA and PFOS at zero and the enforceable Maximum Contaminant Levels at 4.0 parts per trillion (ppt) for both compounds. These are among the most stringent drinking water standards for PFAS nationwide. EPA additionally set the MCLGs and MCLs for PFNA, PFHxS, and “GenX Chemicals” at 10 ppt. Public Water Systems (PWSs) will be required to implement monitoring and reporting measures within three years following the rule’s finalization.

The NPDWR will, for the first time, also use a Hazard Index approach for regulating mixtures of PFHxS, GenX chemicals, PFNA, and PFBS due to their additive toxic effects and likely co-occurrence in drinking water. The Hazard Index is a new tool for defining variable MCLs under the SDWA, which EPA is using to address the risk of multiple kinds of PFAS in mixture. In the context of PFAS, this approach involves comparing the concentrations of each PFAS to its respective safe concentration level as determined by EPA. These ratios are then summed to create a total hazard score. If the total exceeds a specific threshold, the mixture is considered to exceed the MCL. Use of this Hazard Index is intended to account for the cumulative impact of the chemicals on public health.

Public water systems exceeding the regulatory limits will need to take action to provide compliant drinking water, which might involve installing advanced treatment technologies such as granular activated carbon, ion exchange, reverse osmosis and nanofiltration, or point-of-use technologies. In a March 2024 Technical Support Document, EPA discusses technologies and costs for removing PFAS from drinking water. Maximum removal efficiency from these technologies has been recorded at 90 percent or greater for PFAS compounds, with documentation that the technology can remove these compounds to levels below analytical detection limits. The costs of installing technologies to remove PFAS from drinking water vary significantly depending on the size of the system and the type of technology used. In total, EPA estimates that it will cost $1.5 billion annually for water companies across the U.S. to comply with the regulation, while an independent study commissioned by the American Water Works Association (AWWA) estimates the cost will exceed $3.8 billion annually.

At least three challenges have been filed in the D.C. Circuit challenging EPA’s NPDWR pursuant to Section 1448(a)(1) of the SDWA, 42 U.S.C. § 300j-7(a)(1). The AWWA and the Association of Metropolitan Water Agencies (AMWA) contend that EPA underestimated nationwide costs and benefits and question the agency’s use of a Hazard Index instead of a MCL for mixtures of PFAS. The American Chemistry Council and National Association of Manufacturers claim that EPA exceeded its authority under the SDWA, asserting that the rule is arbitrary and capricious. Additionally, the Chemours Company, a manufacturer of PFAS, petitioned against the new rule, alleging that EPA misuses its authority by promulgating a single MCL for mixtures of PFAS based on an “unprecedented” Hazard Index metric and relies on unsound data regarding the toxicity of certain PFAS compounds proposed to be regulated.

RCRA

EPA has also proposed a rulemaking under the Resource Conservation and Recovery Act (RCRA) to list nine PFAS as hazardous constituents, which would subject them to stricter waste management and disposal requirements under that statute. Hazardous constituents listed under RCRA have toxic, carcinogenic, mutagenic, or teratogenic effects on humans or other life forms.

On February 8, 2024, EPA proposed changes to RCRA by adding the following PFAS compounds:

• Perfluorooctanoic acid (PFOA)
• Perfluorooctanesulfonic acid (PFOS)
• Perfluorobutanesulfonic acid (PFBS)
• Hexafluoropropylene oxide-dimer acid (HFPO-DA, also known as GenX)
• Perfluorononanoic acid (PFNA)
• Perfluorohexanesulfonic acid (PFHxS)
• Perfluorodecanoic acid (PFDA)
• Perfluorohexanoic acid (PFHxA)
• Perfluorobutanoic acid (PFBA)

The potential regulation of these PFAS under RCRA would complement the hazardous substances designations of PFOA and PFOS under CERCLA by strengthening EPA’s ability to address PFAS contamination under the RCRA Corrective Action Program. That program requires facilities that treat, store or dispose of hazardous wastes to investigate and clean up contaminated soil, groundwater, and surface water. These two regulatory initiatives working in tandem would enhance EPA’s overall capacity to manage and remediate PFAS-contaminated hazardous waste sites effectively.

EPA’s multifaceted approach to regulating PFAS, including the CERCLA hazardous substances designations, proposed MCLs under the SDWA, and potential RCRA rulemaking, highlights the agency’s prioritization of these so-called “forever chemicals” for regulation. Other regulatory developments are on the horizon, including finalization of the proposed RCRA rulemaking and the potential addition of additional PFAS compounds to the CERCLA hazardous substances list and/or promulgation of MCLs for additional compounds.