The U.S. Supreme Court reversed and remanded a lower court decision vacating EPA's transport rule, also known as the Cross-State Air Pollution Rule, which sets sulfur dioxide and nitrogen oxides emissions limits for 28 upwind states based on those states' contributions to downwind states' air qualit...

The D.C. Circuit vacated a portion of EPA's 2013 rule regulating air emissions from Portland cement kilns. The court concluded that the emission-related portions of the rule are permissible under the CAA. It also upheld the compliance schedule implementing some of the 2013 rule's emission standards....

The D.C. Circuit upheld the emission standards EPA promulgated in 2012 for mercury and other listed hazardous air pollutants emitted by coal- and oil-fired electric utility steam generating units. The rule was challenged by industry, saying the rule was too stringent, as well as by environmental gro...

 The primary standards for carbon monoxide have remained the same since 1971. There has not been a secondary standard for carbon monoxide since EPA revoked a secondary standard in 1985. In 2007, EPA began reviewing whether to alter the current primary standards and whether to adopt a secondary ...

A district court held that the CAA does not preempt landowners' state common-law tort claims against a whiskey distillery for property damage. The landowners alleged that emissions from the distillery caused "whisky fungus" to grow on their property. The distillery filed a motion to dismiss, arguing...