The deadline to file motions in the legal case challenging the Environmental Protection Agency’s (EPA) limits on PFAS chemicals in drinking water has been pushed back again—from August 7 to September 10, 2025. One of the petitioners in the case said they expect the EPA will "redo the regulatory process" for four of the chemicals involved, which they hope will be separated from the current case and not adjudicated.

The case—Association of Metropolitan Water Agencies (AMWA) and the American Water Works Association (AWWA) v. EPA and Lee M. Zeldin (Case No. 24-1188)—was filed with the U.S. Court of Appeals for the D.C. Circuit on June 7, 2024. The EPA requested the case be held in abeyance, and that request was granted on June 5, 2025, resulting in the new filing deadline.

The AMWA and AWWA’s petition for review spans 234 pages, though most of it includes the finalized version of the EPA’s “PFAS National Primary Drinking Water Regulation,” announced by the Biden administration on April 10, 2024, and officially published in the Federal Register on April 26. That regulation is included in the petition as “Exhibit A.”

Separately, on April 19, 2024, the EPA issued another PFAS-related regulation, classifying PFOA and PFOS as hazardous substances under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), commonly known as the Superfund law.

Since the case was filed, several legal representatives have stepped down. On July 10, 2025, Ronald J. Tempas withdrew as attorney for AMWA and AWWA, leaving Corrine Snow as their sole legal representative. Later, on July 25, DOJ attorney Andrew Knudsen also withdrew from representing the EPA, though DOJ lawyer Kimere Kimball remains on the case. No reasons were given for either withdrawal. Additionally, on July 22, the group "Concerned Citizens of WMEL Water Authority Grassroots" withdrew its amicus curiae (friend of the court) brief, again without explanation.

The core of AMWA and AWWA’s challenge focuses on the scientific basis and economic impact of the EPA’s PFAS rule. The petition argues that the agency relied on outdated or insufficient data, used novel methodologies, and failed to follow the rulemaking process required by Congress.

“EPA finalized this rule without following the process mandated by Congress, without allowing the public an adequate opportunity to provide comment, and without addressing the concerns raised by those who work to deliver safe and affordable drinking water to their communities,” the petition claims.

If the case moves forward to the oral argument stage, a three-judge panel in the Court of Appeals will hear the arguments. However, Corrine Snow declined to comment on whether she believes it will reach that point.

Tom Dobbins, CEO of AMWA, told The Driller he believes the EPA will ultimately acknowledge it failed to follow proper procedures under the Administrative Procedure Act when finalizing the rule for four specific PFAS chemicals:

• Perfluorononanoic acid (PFNA)
• Perfluorohexanesulfonic acid (PFHxS)
• Perfluorobutanesulfonic acid (PFBS)
• Hexafluoropropylene oxide dimer acid (HFPO-DA, or GenX)

Because of this, Dobbins said, “Our hope is that those will be separated from the case and will not be adjudicated.”

That said, Dobbins noted the EPA does intend to proceed with adjudicating the rules for the two PFAS chemicals that did follow proper procedures:

• Perfluorooctanoic acid (PFOA)
• Perfluorooctanesulfonic acid (PFOS)

These two “forever chemicals” are known for their persistence in both the environment and the human body due to their durable carbon-fluorine bonds.