The Fifth Circuit granted small refiners' motion to stay certain compliance obligations under the CAA pending appeal of EPA's decision denying their requested hardship exemptions from…

The D.C. Circuit dismissed for lack of standing a petition to review a 2016 EPA rule concerning greenhouse gas emissions and fuel efficiency standards for medium- and heavy-duty engines and…

The D.C. Circuit dismissed an oil company's petition to review EPA's response concerning the decommissioning status of two oil platforms off the California coast. The company initially…

The U.S. Supreme Court held, 6-3, that President Barack Obama's EPA had exceeded its statutory authority under §111(d) of the CAA when it promulgated the Clean Power Plan to address carbon…

A district court denied environmental groups' motion for partial summary judgment in a CAA citizen suit brought against a steel company concerning hydrogen sulfide and sulfur dioxide…

The First Circuit affirmed the Massachusetts Department of Environmental Protection's (MDEP's) decision to issue an air permit for a natural gas compressor station in Weymouth,…

The D.C. Circuit denied a challenge to EPA's 2015 rule updating the standards under which the Agency audits wood-burning heaters' compliance with CAA emissions limits. An industry group…

The Ninth Circuit granted in part and denied in part a petition to review EPA's final rule approving California's SIP for meeting the air quality standard for ozone in the San Joaquin…

The Eighth Circuit affirmed in part and reversed in part a district court ruling in an ongoing enforcement suit concerning air pollution at a utility company's coal-fired power plant in…

A Minnesota appellate court remanded a challenge to the Minnesota Pollution Control Agency's (MPCA's) grant of an air emissions permit for a proposed copper-nickel mine in northern…