The April 2024 EPA rule designating perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) as hazardous substances under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA)—commonly known as Superfund—stands as one of the most consequential PFAS regulatory actions in U.S. history. While the drinking water MCLs established simultaneously primarily affect water utilities and their technology suppliers, the CERCLA designation has sweeping implications for a far broader range of industries: manufacturers, airports, military facilities, waste management companies, and municipalities that may now face strict liability for PFAS cleanup costs.
What CERCLA Hazardous Substance Designation Means
Under CERCLA’s framework, parties that released a designated hazardous substance into the environment are potentially liable for the costs of investigating and cleaning up contamination—even if the release occurred decades ago, complied with all applicable regulations at the time, and the responsible party no longer owns or operates the site. CERCLA liability is strict (no negligence required), joint and several (any one party can be held responsible for the entire cleanup cost if they cannot identify other responsible parties), and retroactive (historical releases are covered). The PFOA and PFOS hazardous substance designation therefore creates retrospective liability for everyone in the chain of PFAS production and use.
Reportable Quantity: 1 Pound Threshold
The EPA set the reportable quantity (RQ) for both PFOA and PFOS at 1 pound—the default minimum RQ under CERCLA. This means that any release of 1 pound or more (approximately 454 grams) of either compound to the environment within a 24-hour period must be reported to the National Response Center. Given the persistence and environmental mobility of PFOA and PFOS, even 1 pound—equivalent to roughly 50 milliliters of concentrated PFAS solution—represents a potentially significant contamination event at the concentrations that trigger drinking water MCL concerns. Industrial facilities, wastewater treatment plants, and landfills with PFAS in their effluent must assess whether their discharge volumes could approach the 1-pound threshold and implement monitoring and notification protocols accordingly.
Who Is Potentially Liable?
CERCLA’s broad liability framework means that potentially responsible parties (PRPs) for PFOA and PFOS contamination could include: PFAS chemical manufacturers (3M, Chemours, DuPont predecessors); AFFF manufacturers; industries that used AFFF—airports, military, refineries, chemical plants; municipalities that operated wastewater treatment plants receiving industrial PFAS discharges; farmers who accepted biosolids containing PFAS; landfill operators; and any property owner at a contaminated site. EPA’s enforcement discretion guidance—issued alongside the hazardous substance designation—stated that EPA would generally not pursue municipalities, farms, or other passive receivers of PFAS contamination, but this guidance is not legally binding and could be revised.
Status Under the Current Administration
The PFOA and PFOS CERCLA designation was challenged in federal court by industry groups and remained subject to legal uncertainty into 2025. The current EPA administration has signaled it is reviewing the designation’s scope, particularly the enforcement discretion guidance for municipal and passive receivers. However, as of mid-2025, the designation remains in effect and continues to generate significant cleanup liability at hundreds of AFFF-contaminated sites that EPA and state agencies have placed on Superfund National Priorities List (NPL) evaluation. Legal costs associated with PFAS CERCLA liability are already running into the billions of dollars annually for major industrial defendants.
Cleanup Technology: The Superfund Market for PFAS Treatment
Superfund cleanups at PFAS-contaminated sites follow EPA’s established remedy selection process, which requires that selected technologies achieve applicable or relevant and appropriate requirements (ARARs)—including state and federal drinking water standards. At sites where PFAS-contaminated groundwater threatens drinking water sources, the remediation remedy typically includes long-term pump-and-treat systems using granular activated carbon, ion exchange resin, or membrane filtration to treat extracted groundwater before it is reinjected or discharged. The CERCLA designation for PFOA and PFOS, combined with the monitoring obligations under the NPDWR, creates a decades-long market for PFAS groundwater treatment technology at NPL and non-NPL contaminated sites across the United States. OEM filter media and system manufacturers with validated performance in Superfund remedy applications—including compliance with EPA’s Quality Assurance/Quality Control requirements for remediation technology—are positioned to compete for what will be one of the most significant environmental services market sectors of the coming decade.