Last month in Chamber of Commerce of the United States of America et al. v. United States Environmental Protection Agency, the D.C. Circuit Court of Appeals denied petitions for review of the United States Environmental Protection Agency’s (“EPA’s” or the “Agency’s”) May 2024 designation of two per- and polyfluoroalkyl substances (“PFAS”) chemicals—perfluorooctanoic acid (“PFOA”) and perfluorooctanesulfonic acid (“PFOS”)—as “hazardous substances” (the “Designation”) under the Comprehensive Environmental Response, Compensation, and Liability Act (“CERCLA” or the “Act”).  The petitions were filed by industry interest groups that use, transport, or discharge PFOA and PFOS (the “Petitioners”).  Read More »

Share | Email| Comments|  Topics: Administrative Procedures Act, Agency Action, CERCLA, Contamination, D.C. Circuit, EPA, Loper Bright, PFAS, Pollutants, Potentially Responsible Parties, Rulemaking, Water

The U.S. Court of Appeals for the Tenth Circuit issued a decision on August 3, 2026, which clarified the scope of the diligent prosecution bar to citizen suits under the Clean Air Act (“CAA”).  The decision was a partial victory for the environmental organizations that brought the lawsuit and adds to the body of appellate decisions aiming to elucidate this heavily litigated area of the law. Read More »

Share | Email| Comments|  Topics: Air, CERCLA, Citizen Suit, Citizens Suit, Clean Air Act, Colorado, Consent Decree, Diligent Prosecution, Emissions, EPA, Loper Bright, Pollutants, Superfund, Tenth Circuit