The U.S. Environmental Protection Agency is continuing its legal effort to pause parts of its Biden-era drinking water standards for certain PFAS chemicals while it develops a new rule that would rescind one key component. The regulation established individual limits for PFOA and PFOS and introduced a first-of-its-kind “hazard index” to regulate four additional PFAS—PFNA, PFHxS, PFBS, and GenX—as a group.
In January, the U.S. Court of Appeals for the D.C. Circuit denied EPA’s request to vacate the hazard index portion. The agency is now seeking to separate that provision from the broader legal challenge as it prepares a formal proposal to eliminate it.