Jump to Navigation
Jump to Content

National ambient air quality standards (NAAQS), §109

EME Homer City Generation, L.P. v. Environmental Protection Agency

The D.C. Circuit, on remand from the U.S. Supreme Court, invalidated EPA's 2014 emissions budgets under the transport rule, also known as...

Mississippi Commission on Environmental Quality v. Environmental Protection Agency

The D.C. Circuit denied petitions for review of EPA decisions regarding nonattainment designations under the 2008 ozone NAAQS. Several states, counties, industrial entities, and environmental organizations petitioned the court...

Westar Energy, Inc. v. Environmental Protection Agency

The D.C. Circuit denied petitions for review challenging EPA's disapproval of a revision to Kansas' proposed SIP revision for the 2006 fine particulate matter (PM2.5) NAAQS. EPA disapproved the SIP revision because the submission lacked...

Save the Scenic Santa Ritas v. Darwin

An Arizona court overturned the state's issuance of an air permit for a proposed open-pit copper mine. An environmental group argued that the state's approval of the permit was arbitrary and capricious because the mine has the potential...

Natural Resources Defense Council v. Environmental Protection Agency

The D.C. Circuit held that EPA's regulations implementing the 2008 NAAQS for ozone exceed the Agency’s authority under the CAA. In 2008, EPA revised and strengthened the standards for ozone pursuant to the CAA. One of the revisions...

Center for Biological Diversity v. Environmental Protection Agency

The D.C. Circuit upheld EPA’s decision to defer adopting new secondary NAAQS for oxides of sulfur (SOx) and nitrogen (NOx) pending further scientific study. Citing doubts about the accuracy of its aquatic acidification index model—used...

National Ass'n of Manufacturers v. Environmental Protection Agency

The D.C. Circuit denied industry groups' petition for review challenging EPA's 2013 primary NAAQS for fine particulate matter. In the final rule, EPA lowered the level of the particulate matter NAAQS from 15.0 μg/m3 to 12.0 μg/m3, a...

Communities for a Better Environment v. Environmental Protection Agency

 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...

Sierra Club v. Department of Environmental Quality

The Michigan Court of Appeals, in an unpublished opinion, upheld the state environmental agency's decision to issue two permits authorizing modifications at a coal-fired power plant. The plant is located in a county that violates the...

Sierra Club v. United States Environmental Protection Agency

A district court denied industry groups' motion to intervene in a CAA citizen suit concerning EPA's alleged failure to review the ozone NAAQS in a timely manner. The underlying lawsuit concerns whether EPA has failed to perform a...