EPA Retains the Designation of Certain PFAS as Hazardous Substances Under CERCLA

The U.S. Environmental Protection Agency (EPA) recently announced it will retain the Biden Administration’s rule designating two types of polyfluoroalkyl substances (PFAS)—perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS)—as hazardous substances under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA, also known as Superfund). This article will explain the EPA’s final rule designating certain PFAS as hazardous substances under CERCLA, the implications of these designations, potential enforcement actions and current challenges to these designations.

EPA’s Final Rule

The final rule to designate PFOA and PFOS as hazardous substances is currently being challenged in the D.C. Circuit Court of Appeals by a variety of trade associations and industry groups.  At the beginning of the Trump Administration, the U.S. Department of Justice (DOJ) sought and received, a stay of the case to allow EPA to reconsider designating PFOA and PFOS as hazardous substances.  On September 17, the DOJ advised that EPA was retaining the rule and wished for litigation over the rule to move forward.

Implications for Businesses and Industries

The designation of PFOA and PFOS as hazardous substances has many implications for a variety of businesses and industry.  Most notably, CERCLA imposes strict liability on certain classes of parties—designated as potentially responsible parties (PRPs)—for the cost to clean up hazardous substances at Superfund sites, which now include PFOA and PFOS.  PRPs under CERCLA include not only entities that generated or disposed of PFOA or PFOS, but also landowners where the substances eventually were disposed of—even where the landowners purchased the property after the disposal occurred.  In most cases, where there are multiple PRPs at a cleanup site, all PRPs are jointly and severally liable for the cost of the entire cleanup.  Furthermore, PRPs are liable to cleanup PFOA and PFOS even if they were disposed of prior to them being designated hazardous substances.

EPA’s rule could have numerous consequences with respect to Superfund sites.  First, it could lead to the creation of new Superfund sites to specifically address PFOA and PFOS contamination.  Second, the rule could increase the scope of cleanup activities at active Superfund sites by now requiring cleanup of PFOA and PFOS in addition to previously identified contaminants of concern. Third, it could lead to the reopening of closed Superfund sites to address PFOA and PFOS that would not have been previously addressed.  Since PFAS were widely used and their components break down very slowly over time, for a majority of Superfund sites it will not be a question of whether PFAS are present, but whether they are present in amounts requiring remedial actions. 

Potential Enforcement Actions

At the same time EPA listed PFOA and PFOS as hazardous substances, it issued a PFAS Enforcement Discretion and Settlement Policy Under CERCLA. Under that policy, EPA “will focus on holding responsible entities who significantly contributed to the release of PFAS into the environment, including parties that manufactured PFAS or used PFAS in the manufacturing process, federal facilities, and other industrial parties.” 

EPA also stated that it did “not intend to pursue entities where equitable factors do not support seeking response actions or costs under CERCLA, including, but not limited to:

• Community water systems and publicly owned treatment works,
• Municipal separate storm sewer systems,
• Publicly owned/operated municipal solid waste landfills,
• Publicly owned airports and local fire departments, and
• Farms where biosolids are applied to the land. 

Those entities are often called “passive receivers,” as they did not cause the contamination, and EPA appears to continue to support this Biden-era approach to enforcement.  In fact, EPA announced that it would work with Congress to create a statutory fix to protect passive receivers from PFAS liability under CERCLA.

Notwithstanding EPA’s policy of enforcement discretion, states and Tribal Governments may also order cleanups of PFOA and PFOS under the authority granted to them under CERCLA.  In addition, private parties are generally entitled to recover a portion of their costs spent to clean up hazardous substances under CERCLA from PRPs, which would now include PFOA and PFOS. 

Although the largest impact of designating PFOA and PFOS as hazardous substances under CERCLA relates to potential cleanup costs at Superfund sites, the designation has several other ramifications as well.

These are:

• Under CERCLA sections 103 and 111(g) and section 304 of the Emergency Planning and Community Right-to-Know Act (EPCRA), facilities must report releases of one pound of PFOA or PFOS within a 24-hour period.
• Under EPA’s All Appropriate Inquiries Rule, which is the process for evaluating a property’s environmental conditions, PFOA and PFOS must now be considered during the Phase I Environmental Site Assessment Process as set forth in ASTM International Standard E1527-21. In addition, CERCLA section 120(h) requires federal agencies that sell or transfer real property to provide notice of the presence of PFOA or PFOS in certain circumstances.
• CERCLA section 306 requires the U.S. Department of Transportation to regulate any substance added to the CERCLA list as hazardous materials in accordance with the Hazardous Materials Transportation Act (HMTA).

Current Challenges to EPA’s Final Rule

Although the designation of PFOA and PFOS is currently in effect, EPA’s final rule is being challenged in the U.S. Court of Appeals for the D.C. Circuit.  Petitioners argue, in part, that EPA misinterpreted the requirement that a hazardous substance “may present substantial danger” and failed to provide adequate notice and comment regarding its cost-benefit analysis for the Rule.  Briefing in that case is likely to be completed in the fall of 2025 with oral argument likely in Spring 2026.

The regulatory landscape with respect to PFAS is rapidly changing at both the state and federal levels.  This decision by EPA comes on the heels of its prior decision to maintain the current National Primary Drinking Water Regulations (NPDWR) for the two most common PFAS—PFOA and PFOS—while rescinding regulations for several other PFAS.

Almost every industry could be affected by EPA’s designation of PFOA and PFOS as hazardous substances, but entities currently involved in the cleanup of Superfund sites should be particularly cognizant of this rule’s potential impact. 

Please contact Phillip Dupré or any member of the Phelps Environmental team if you have any questions or need advice or guidance.