The court vacates the Environmental Protection Agency's (EPA's) approval of a county's Clean Air Act (CAA) new source review (NSR) program because EPA did not adequately assess…

The court remands three portions of technical amendments the U.S. Environmental Protection Agency (EPA) made to its nitrogen oxide (NOx) state implementation plan (SIP) call rulemaking that…

The court denies a petition to review the U.S. Environmental Protection Agency's (EPA's) approval of a revision to Missouri's Clean Air Act (CAA) state implementation plan that…

The court holds that the U.S. Environmental Protection Agency (EPA) has the power under the Clean Air Act (CAA) to adopt de minimis exemptions for sources of pollution from particulate matter…

The court affirms the U.S. Environmental Protection Agency's (EPA's) disapproval of a revision to the Michigan Clean Air Act (CAA) state implementation plan (SIP) that automatically…

The court upholds the U.S. Environmental Protection Agency's (EPA's) approval of the Nevada Clean Air Act (CAA) state implementation plan (SIP) revision that requires gasoline sold in…

The court largely upholds a U.S. Environmental Protection Agency (EPA) rule mandating that 22 states and the District of Columbia revise their state implementation plans (SIPs) to mitigate ozone…

The court grants automakers' motion to stay their challenge to Massachusetts' zero emission vehicle standards pending the automakers' appeal of a U.S. Environmental Protection…

The court holds unlawful U.S. Environmental Protection Agency (EPA) regulations that allow both local approval and federal funding of transportation projects that fail to satisfy the Clean Air Act…

The court holds that an electric utility lacks standing to petition for review a U.S. Environmental Protection Agency (EPA) final rule approving a revision to the new source review program of…