EPA Advances New PFAS Actions

On 18 May 2026, Environmental Protection Agency (EPA) issued two proposed rules addressing the National Primary Drinking Water Regulation for per- and polyfluoroalkyl substances (PFAS). These actions follow previous pronouncements by the agency to: “advance[] the science-based levels for perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS)... while revising compliance dates to ensure successful implementation.”¹

The first proposed rule would retain the existing maximum contaminant levels (MCLs) for PFOA and PFOS—set at 4.0 parts per trillion each. This proposed rule will also extend the dates of compliance from 26 April 2029 to 26 April 2031 for eligible systems that submit a request. EPA explained the need for the extension stems from implementation challenges for certain systems, including small, rural, and disadvantaged communities that face financial limitations. In order to be eligible for the extension, a water system must show compelling factors that it is unable to comply and that the extension will not result in an unreasonable risk to health. EPA highlighted that allowing drinking water systems to seek additional time may allow the cost of PFAS removal technologies to come down through technological advancements and production efficiencies.

The second proposed rule would rescind the regulatory determinations, maximum contaminant level goals (MCLGs), and MCLs for four additional PFAS regulated under the 2024 rule—perfluorohexane sulfonic acid (PFHxS), perfluorononanoic acid (PFNA), hexafluoropropylene oxide dimer acid (HFPO-DA, commonly known as GenX), and a hazard index mixture of those three plus perfluorobutane sulfonic acid (PFBS). EPA’s proposed rule explains this action is necessary to correct the unlawful procedure under which these regulations were originally promulgated. If finalized, EPA has committed to re-evaluating these substances using the correct statutory process, including a more robust public comment solicitation. 

Alongside these proposed rules, EPA announced nearly US$1 billion in new grant funding through the Emerging Contaminants in Small or Disadvantaged Communities Grant program to help water systems address PFAS in drinking water. EPA’s announcement also highlights its recently updated PFAS Destruction and Disposal Guidance. This update identifies available and effective methods to remediate, dispose of, and destroy PFAS contamination. The three existing technologies identified by EPA as having lower potential for environmental release of PFAS are thermal destruction, landfills, and underground injection. EPA’s updated guidance also includes a new technology evaluation framework to assess the safety and effectiveness of these emerging tools, including analytical methods, disposal/destruction efficacy, community considerations, and regulatory requirements. The guidance reiterates that PFAS destruction and disposal research is ongoing and new approaches for management will continue to be evaluated.

The EPA will hold a virtual public hearing on 7 July 2026 and comments for both proposed rules must be received on or before 20 July 2026.

Our Emerging Contaminants group is tracking critical and evolving developments for newly regulated contaminants on our Emerging Contaminants webpage. The Emerging Contaminants webpage is also where you can find a listing of our lawyers able to assist you in navigating and managing these issues on a cross-practice basis.