The California Supreme Court held that a county's policy of approving permits for new water wells without environmental review violated the California Environmental Quality Act (CEQA).

The First Circuit amended a previous ruling vacating an air permit issued by the Massachusetts Department of Environmental Protection (MDEP) for a proposed natural gas compressor station that is part of a pipeline connecting the northeastern United States and Canada.

The Second Circuit vacated a final rule published by the National Highway Traffic Safety Administration (NHTSA) that reversed the agency's 2016 civil penalty increase for noncompliance with Corporate Average Fuel Economy (CAFE) standards.

The Third Circuit held that a PRP's settlement with New Jersey resolving its state-law liability in connection with contamination at a municipal landfill did not protect the party from lawsuits seeking contribution toward expenditures made by EPA on the same site.

The Ninth Circuit vacated dismissal of a Federal Tort Claims Act (FTCA) lawsuit brought against the U.S. government concerning pollution from an abandoned military facility in Alaska.

A district court held that an oil company was liable for a plume of gasoline beneath a former gasoline station that was migrating toward nearby housing units in White Plains, New York.

A district court denied a motion to preliminarily enjoin further construction of a 429-mile natural gas pipeline in Texas.