The D.C. Circuit vacated three provisions of EPA's 2018 rule implementing NAAQS for ozone. Environmental groups challenged four provisions of the rule: the interprecursor trading program, a…

The D.C. Circuit vacated EPA's Affordable Clean Energy Rule that repealed and replaced the Clean Power Plan as a means of regulating power plants' greenhouse gas emissions. A group of…

The Fifth Circuit denied petitions to review EPA's 2018 redesignation of Bexar County, Texas, from attainment to nonattainment and designation of three neighboring counties as attainment/…

The Eighth Circuit affirmed, 2-1, a ruling in favor of a mining company in a challenge to the company's failure to obtain a CAA construction permit for a mine in rural North Dakota. The…

The Fourth Circuit granted for a second time an oil refinery's petition to review EPA's decision denying the refinery an exemption from biofuel requirements under the Agency's…

The Third Circuit granted a petition to review EPA's approval of Pennsylvania's proposed NAAQS for ozone. An environmental group argued the standards wrongly claimed to reduce pollution…

The D.C. Circuit denied in part and dismissed in part a petition to review EPA's guidance concerning the process of certifying cellulosic biofuel. A biofuel company argued the guidance was a…

The Fifth Circuit vacated and remanded a lower court decision that imposed penalties against an oil company for alleged CAA permit violations at its industrial complex in Baytown, Texas.…

A district court granted states' motion for summary judgment in a lawsuit concerning EPA's duty to limit air pollution drifting from upwind states into northeastern states. Connecticut,…

The D.C. Circuit vacated EPA's denial of New York's petition concerning cross-border pollution from nine upwind states. The state had asked EPA to find that power-generating and other…