By Jeffrey Karp, Senior Counsel, and Edward Mahaffey, Legal Research and Writing Attorney

The Environmental Protection Agency’s new drinking water health advisories for PFAS, released on June 15, 2022, included an advisory level of 10 parts per trillion (ppt) for hexafluoropropylene oxide dimer acid and its ammonium salt, collectively known as GenX. On July 14, 2022, Chemours, which manufactures GenX, petitioned the United States Court of Appeals for the Third Circuit for review of the GenX health advisory. In its filing, Chemours argued that the health advisory was “arbitrary and capricious” by challenging EPA’s scientific assumptions, but Chemours also made a more radical argument: “The manner in which EPA has used its Safe Drinking Water Act authority to issue health advisories violates constitutional requirements, including the nondelegation doctrine, because EPA has utilized unfettered discretion to publish health advisories,” and had thus affected “the legal rights and obligations of companies, water utilities, and others across the country without sufficient legislative direction or regulatory safeguards.”[1]