EPA Retains CERCLA PFAS Rule: Implications for Wastewater Utilities

*Updated September 2025: This article has been updated to reflect the U.S. EPA’s decision to retain the CERCLA rule designating PFOA and PFOS as hazardous substances.

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In September 2025, the EPA reaffirmed its decision to retain the Biden-era rule designating PFOA and PFOS as hazardous substances under CERCLA (Superfund). For clean water agencies, this sustained designation raises important questions: How will it affect operations? What liability risks and funding challenges might arise? And what proactive steps can be taken to safeguard systems and ratepayers?

The CERCLA designation requires entities to report releases of PFOA and PFOS that meet or exceed the reportable quantity, enabling regulators, states, and private parties to pursue cleanup and cost recovery actions (EPA press release). The EPA’s goal is to increase transparency around PFAS releases and ensure that those responsible for contamination bear the financial burden of remediation. Additionally, in 2024, the EPA proposed adding PFOA, PFOS, and seven other PFAS compounds to the list of “hazardous constituents” under the Resource Conservation and Recovery Act (RCRA), expanding regulatory oversight.

These regulatory developments could significantly impact publicly owned treatment works (POTWs), especially those considered “passive receivers”—entities that did not manufacture or use PFAS but may still face liability due to contamination. The EPA has acknowledged this concern and is seeking a statutory fix from Congress to protect such entities from undue liability.  

To navigate these evolving challenges, POTWs should stay informed on regulatory updates, assess potential exposure risks, and explore available funding sources to support compliance and infrastructure upgrades.

Effects of CERCLA and RCRA Designations for POTWs

The PFOA and PFOS designation as hazardous substances, allows EPA, state regulators, and private citizens to hold dischargers and others responsible for PFOS and PFOA contamination, even if they had no role in creating it. This could result in legal implications for clean water agencies. Recognizing that POTWs are not producers of PFAS chemicals, EPA announced it will focus its enforcement efforts on manufacturers and producers of PFAS. However, this enforcement discretion does not shield POTWs from risk. States and other groups have already cited the CERCLA rule in lawsuits, showing that utilities could still be pulled into legal battles despite EPA’s stated focus on manufacturers. Because CERCLA liability is strict and retroactive, POTWS remain vulnerable unless Congress enacts new protections.  

There are technologies on the market that remove and destroy PFAS, which can keep wastewater plants compliant with CERCLA and other regulatory requirements, reduce contamination risk, and protect the health of communities and their surrounding environments. However, treatment costs and the potential legal liability could disrupt utility and city budgets, making the proper steps to remove contamination unattainable for often underfunded POTWs.

How a Wastewater District is Holding PFAS Polluters Accountable

As the public and regulators shift their attention towards wastewater, many systems are looking to retain counsel and file a lawsuit against PFAS manufacturers to seek cost recovery for their PFAS contamination and treatment. These systems have chosen to rely on specialized legal counsel who can advise them based on their utility’s unique needs. This approach proved effective in the case of drinking water suppliers, whose lawsuits against PFAS manufacturers over the past several years resulted in four proposed settlements, from 3M Company, the DuPont group of companies, and Aqueous Film Forming Foam (AFFF) manufacturers Tyco and BASF, providing a total of more than $12 billion to clean up PFAS in drinking water.

York Sewer District in Maine, for example, discovered PFAS in its wastewater system while testing its biosolids as part of the Maine Department of Environmental Protection’s new requirements. The District determined that household items, such as non-stick cookware, cleaning, and stain-resistant products were the source of contamination—rather than local drinking water supplies, where PFAS has never been detected.

Concerned about the impact of these chemicals to the community’s infrastructure and finances, in late 2023, the District hired SL Environmental Law Group to sue 3M, DuPont, and other PFAS manufacturers in order to recover the costs the District would incur as a result of PFAS in its effluent and biosolids. The aim of the lawsuit, which is part of the same ongoing AFFF multi-district litigation against PFAS manufacturers that produced the drinking water settlements, is to recover funds to keep the District in regulatory compliance and protect public health without financially burdening its ratepayers.

How to Take Action Now

Holistic PFAS regulations aim to reduce the harm these chemicals can cause and have inflicted for generations. But the encompassing approach to removing PFAS from the environment has substantial financial implications for water and wastewater providers nationwide. While some federal and state funding may be available to these providers, industry cost estimates reveal these sources will likely be insufficient. Litigation remains an attractive funding route for a number of wastewater utilities, if they will become burdened by additional testing, reporting, and treatment requirements, and potentially lawsuits from private parties and state governments.

About SL Environmental Law Group

SL Environmental Law Group, P.C. is a nationally recognized firm committed to helping public and private agencies recover the costs of cleaning up environmental contamination. Over the past two decades, the firm has secured more than $2 billion in settlements and trial verdicts for over 400 clients—including nearly $1 billion for agencies in Phase 1 of the PFAS water settlements. SL Environmental represents more than 300 clients in the ongoing PFAS multidistrict litigation (MDL), working to hold manufacturers accountable for widespread contamination and to shift the financial burden away from affected communities.