By Joel Eagle, a partner in the Cleveland, OH office of Thompson Hine LLP.

Over the past decade or so, the legal developments involving the large family of per- and polyfluoroalkyl substances (PFAS) in the U.S. have included a steady stream of litigation in various forms including suits related to site contamination, personal injury, and product liability. But with the proliferation of so many new finalized and proposed federal, state, and local regulations and statutes, and the sustained drumbeat of national and worldwide attention (some would say craze) associated with these so-called “forever chemicals,” a new wave of PFAS litigation is on the horizon.

On March 29, 2023, the United States Environmental Protection Agency (EPA) published in the Federal Register its proposal rule, “PFAS National Primary Drinking Water Regulation Rulemaking,” which would for the first time set national drinking water standards—commonly referred to as maximum contaminant levels (MCLs)—for six different PFAS chemicals. The proposed federal PFAS MCLs are just one of many recent PFAS developments increasing the risks and opportunities for litigation by and among private and public entities and government agencies at all levels. This Legal Opinion Letter focuses on the proposed PFAS MCL rulemaking, but as a preview of things to come, PFAS litigation could also stem from:

1. EPA’s August 2022 proposed rule that would list perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), two of the most widely studied and regulated of the many thousands of PFAS compounds, as “hazardous substances” under the federal Comprehensive Environmental Response, Compensation and Liability Act (CERCLA);
2. private disputes related to site remediation of PFAS chemicals;
3. new state laws and regulations that limit or prohibit PFAS in food packaging, other food products, and a broader set of consumer goods;
4. personal injury and property damage under state statutes and common law;
5. administrative enforcement and litigation for PFAS releases like the April 2023 EPA announcement of the first-ever enforcement of PFAS releases under the Clean Water Act for violations of a facility’s National Pollution Discharge Elimination System (NPDES) permit;
6. contract disputes from corporate and real estate transactions at sites with known or previously unknown PFAS contamination; and
7. claims for coverage pursuant to historical or current insurance policies related to PFAS liabilities of various types.

The extent of ongoing and future legal PFAS issues can be humbling and certainly difficult to stay abreast of at times. This Legal Opinion Letter examines EPA’s March 2023 proposed rule that would set MCLs for six PFAS compounds. Many states, including Michigan and New Jersey, have had enforceable state drinking water standards for several years, but the prospect of a nationwide standard has long loomed without EPA action, until now.

EPA’s inaction changed with the proposed drinking water rule, which proposes to set standards for PFOA (4 parts per trillion, PPT), PFOS (4 PPT), perfluorononanoic acid (PFNA), perfluorohexanesulfonic acid (PFHxS), perfluorobutane sulfonic acid (PFBS), and hexafluoropropylene oxide-dimer acid and its ammonium salt (HFPO-DA), commonly known as “GenX” chemicals, as a PFAS mixture with a Hazard Index of 1. The EPA Hazard Index is based on a regulatory equation that compares the level of each PFAS measured in the water to the highest level determined not to have risk of health effects.

While EPA’s proposed MCLs of 4 PPT is, in fact, 1,000 times higher than the unheard of 4 parts per quadrillion (PPQ) level that EPA announced as non-binding Health Advisory Levels (HALs) for PFOS and PFOA in June 2022, 4 PPT is still extremely low and is essentially the lowest possible level at which laboratories can currently detect these compounds. Environmental attorneys and consultants are accustomed to dealing with MCLs in the parts per million or parts per billion, but PPT and PPQ are quickly becoming the norm in PFAS discussions.

These exceptionally low MCLs will almost certainly inspire legal challenges, starting with private industry or industry group challenges of the final rule under the Administrative Procedure Act (APA). APA suits will most likely focus on the science supporting EPA’s decision and would contend that the EPA acted in an arbitrary and capricious manner in establishing these MCLs.

Another legal challenge to the PFAS MCLs could be based on the “major questions doctrine,” which rose from obscurity with the U.S. Supreme Court’s 2022 West Virginia v. U.S. decision. The decision invalidated EPA’s attempt to enforce power generation-shifting regulations by limiting emissions.

Although the major questions doctrine arguably would only apply in cases of vague statutory interpretation—and setting a new MCL for a drinking water contaminant is squarely within EPA’s authority under the Safe Drinking Water Act—creative legal theories are possible. Based on a theme in the West Virginia ruling, for example, one argument may be that regulating PFAS, which are ubiquitous in the U.S., has extraordinary economic and political significance, and thus Congress should address such issues under separation-of-power principles. Indeed, for several years, Congress has debated various forms of the “PFAS Action Act” (e.g., of 2019, of 2021), which included mandates for EPA to take certain actions including setting drinking water MCLs for certain PFAS. A major questions doctrine argument may be a stretch, but with the current Court’s skeptical view of the administrative states and the precedent set by West Virginia, such an argument is not beyond the realm of possibility.

Should challenges to the final EPA rule fail, additional litigation is foreseeable. Public water systems, for example, will be subject to meeting the low PFAS MCLs or treating drinking water levels should MCLs be exceeded. The technical challenges and attendant costs of treating drinking water for PFAS may force affected water suppliers to seek recovery from the upstream parties that released the compounds into the environment. The MCLs may also become Applicable or Relevant and Appropriate Requirements remediation standards for these PFAS compounds at contaminated sites around the country. Again, someone must bear the high PFAS remediation costs and technical complexities in capturing, treating, and disposing of the PFAS compounds, and responsible parties at sites for conventional pollutants may have no choice but to search for other parties to bring to the table.

Over the past several years, EPA has been all in on PFAS regulation and enforcement, as evidenced by the agency’s comprehensive PFAS Strategic Roadmap of 2021, which replaced the PFAS Action Plan of 2019. The PFAS Strategic Roadmap calls for EPA to set MCLs for certain PFAS, but also seeks to hold accountable the parties that caused PFAS releases. On April 26, 2023, EPA announced the first enforcement action under the Clean Water Act, resulting in an Administrative Order on Consent (AOC), with a PFAS manufacturer related to PFAS exceedances of a NPDES discharge permit. Had the facility not agreed to the AOC, the government could have pursued administrative or possibly civil enforcement through the Department of Justice. Although EPA is currently working on an enforcement discretion policy that would place primary scrutiny on the private parties that caused the PFAS releases, EPA has made it clear that this enforcement discretion is only intended for CERCLA cleanups and no other federal environmental statutory programs (like the CWA).

If all these litigation risks don’t cause one’s head to spin, consider also that the Clean Water Act authorizes citizen-suit enforcement of MCLs and requires site remediation, as do other federal statutes, including the Clean Air Act (CAA) and the Resource Conservation and Recovery Act (RCRA). While CWA, CAA and RCRA citizen suits may only be sustained if the government is not “diligently prosecuting” the matter already, the ubiquity of PFAS presents unprecedented burdens on a resource-limited EPA to enforce against so many potential targets at once.

In summary, the proposed PFAS MCL rule presents a high potential for litigation and other legal risks. Considering the breadth of other possible federal, state, local, contract, and common law causes of action associated with PFAS in the U.S. (not to mention the worldwide attention PFAS is receiving), it’s reasonable to say that “PFAS litigation” will soon surpass “asbestos litigation” as the environmental litigation de jure for the next several decades. Given the legal activity of the last several years, that torch may already have been passed. I’ve authored articles and conducted presentations with titles such as “PFAS-ten Your Seatbelts” and “PFAS and Furious,” but with PFAS regulation and litigation at its current stage in the U.S., it’s clear that some new creative titles are now needed.