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

In a significant decision for Clean Air Act enforcement, the U.S. District Court for the Eastern District of California held that citizens may pursue Clean Air Act claims against a state or local air agency in their regulatory capacity for allegedly failing to carry out State Implementation Plan (SIP) obligations. Read More »

Share | Email| Comments|  Topics: Agency Action, Air, California, Citizen Suit, Clean Air Act, Emissions, Hazardous Air Pollutants, Pollutants

In West Virginia Rivers Coalition, Inc., et al. v. The Chemours Company FC, LLC, the Court of Appeals for the Fourth Circuit vacated a district court decision to preliminarily enjoin The Chemours Company (“Chemours”) from discharging hexafluoropropylene oxide dimer acid (“HFPO-DA”)—a Chemours-created PFAS chemical— from its Washington Works facility in excess of its permitted limit.  In doing so, the Fourth Circuit took no issue with the district court’s standing analysis, but determined the district court made legal and factual errors in its irreparable harm determination. Read More »

Share | Email| Comments|  Topics: Citizens Suit, Clean Water Act, Contamination, Drinking Water, Fourth Circuit, Injunction, Permits, PFAS, Pollutants, Standing, Water

The United States District Court for the District of New Jersey dismissed a class action lawsuit against Johnson & Johnson entities and Kenvue, Inc. concerning the presence of per- or polyfluoroalkyl substances (“PFAS”) in Band-Aid products on grounds of standing. This case, Jo Aronstein, et al. v. Kenvue, Inc. et al., is one of many class action lawsuits that have been filed in recent years concerning PFAS in consumer products and offers some insight into how courts are approaching these suits in various jurisdictions. Read More »

Share | Email| Comments|  Topics: Class Actions, Contamination, Drinking Water, New Jersey, PFAS, Pollutants, Standing, Water

A federal district court in Massachusetts recently issued companion decisions addressing the “useful product defense” in the context of biosolids that contain per- and polyfluoroalkyl substances (PFAS).  In twin orders dated December 30, 2025, the court held that biosolid pellets, or “biopellets”—which are produced from treated wastewater solids and used as fertilizer—are “useful products,” providing a defense to liability under Massachusetts’s analogue to the federal Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). Read More »

Share | Email| Comments|  Topics: CERCLA, Class Actions, Contamination, Drinking Water, Massachusetts, Negligence, Nuisance, PFAS, Pollutants, Water

The Ninth Circuit’s November 5^th decision in Coastal Environmental Rights Foundation, v. Naples Restaurant Group, LLC exploded onto the scene -- deepening an existing circuit split on whether a Clean Water Act citizen suit stays alive based solely only civil penalties once the alleged wrongful conduct ceases.  Consistent with the Eighth Circuit, the Ninth Circuit answered this question in the negative in Naples Restaurant.  The Second, Third, Fourth, Seventh and Eleventh Circuits have previously answered the question in the affirmative.  Overall, the key takeaway is for parties to make sure they are cognizant of the prevailing rule in their Circuit, and to be prepared to raise or respond to the arguments implicated by the Naples Restaurant opinion. Read More »

Share | Email| Comments|  Topics: Citizen Suit, Citizens Suit, Civil Penalties, Clean Water Act, Enforcement, Ninth Circuit, NPDES, Permits, Pollutants, Water

This month, the United States Court of Appeals for the Ninth Circuit held in Confederated Tribes of the Colville Rsrv. v. Teck Cominco Metals Ltd, No. 24-5565, 2025 WL 2525853 (9th Cir. Sept. 3, 2025) that CERCLA permits recovery of natural resource damages with a cultural use component, effectively reversing the district court’s holding that cultural resource damages are not authorized under CERCLA. Read More »

Share | Email| Comments|  Topics: CERCLA, Citizen Suit, Citizens Suit, Contamination, Natural Resource Damages, Ninth Circuit, Pollutants, Tribal Lands, Water, Water Use

A recent decision sheds light on the U.S. government’s cleanup obligations in land sales involving former military sites.  In Hamilton Square, LLC v. United States, No. 20-1285 (Fed. Cl. July 15, 2025), the U.S. Court of Federal Claims allowed a key environmental remediation claim to proceed while dismissing others in a suit alleging the Navy breached its obligation to remediate newly discovered petroleum and chloroform contamination at a property in Novato, California. Read More »

Share | Email| Comments|  Topics: Breach of Contract, CERCLA, Cleanup, Contamination, Court of Federal Claims, Oil and Gas, Pollutants, Remediation, Vapor Intrusion

On July 9^th, 2025, the Eastern District of New York ruled on a series of motions in Suffolk County Water Authority v. Dow Chemical Company, a case brought by the Suffolk County Water Authority (“Suffolk”) against chemical manufacturers for the alleged contamination of Suffolk’s groundwater supply with 1,4-dioxane (“dioxane”), a chemical classified by the EPA as a “probable human carcinogen.”  Judge Gershon issued an opinion allowing most of the plaintiff’s common law tort claims to proceed to trial while clarifying the standard for expert admissibility under recently amended Federal Rule of Evidence 702. Read More »

Share | Email| Comments|  Topics: Causation, Contamination, Drinking Water, Evidence, Expert Witness, Groundwater, Negligence, New York, Nuisance, Pollutants, Strict Liability, Trespass, Water