The Tenth Circuit dismissed as moot an environmental group's CAA citizen suit against an energy company for building a new coal-fired power plant in Pueblo, Colorado, without a valid construction permit. Although the project initially complied with all applicable federal and state laws when construc...

The Sixth Circuit vacated EPA's determination that a natural gas operation's plant and production wells separately located within a 43-square-mile area constitute a single stationary source under the CAA Title V permitting program. EPA concluded that the facilities satisfy the regulatory requirement...

The Fifth Circuit upheld an EPA rule partially approving and partially disapproving revisions to Texas' SIP concerning civil penalties for excess emissions resulting from startup, shutdown, and malfunction (SSM) activities. Environmental petitioners sought review of EPA's decision to approve a revis...

The D.C. Circuit denied petitions challenging EPA's one-hour primary NAAQS for nitrogen dioxide (NOx). The new one-hour primary NAAQS requires that “the three-year average of the annual 98th percentile of the daily maximum one-hour average concentration be less than or equal to 100 parts per billi...

The D.C. Circuit dismissed petitions challenging EPA's primary NAAQS for sulfur dioxide (SO2). The petitioners—several states, state regulatory agencies, corporations, and industrial associations—argued that EPA failed to follow the APA's notice-and-comment rulemaking procedures because it did n...

A California appellate court upheld a local air district rule that requires manufacturers of consumer paint thinner and solvent products to limit the use of ozone-forming volatile organic compounds (VOCs) in their products. The district issued to rule to satisfy its federal CAA commitments. A pa...

The California Supreme Court upheld an air district's technology-forcing rules that limit certain pollution-causing substances in paints and coatings. A paint association argued that the air district failed to show that technology necessary to meet the emissions limits set by the 2002 amendments...

The D.C. Circuit upheld four EPA rulemakings governing greenhouse gases. EPA issued the rules following the U.S. Supreme Court's decision in Massachusetts v. EPA, 549 U.S. 497 (2007), in which the Court clarified that greenhouse gases meet the definition of an air pollutant under the CAA. Petit...

The Fifth Circuit upheld EPA's decision to disapprove certain revisions to Texas' SIP. EPA disapproved the revisions concerning the state's "qualified facilities program" because it did not meet the minor new source review (NSR) SIP nor did it meet the NSR SIP requirement for a substitute major ...

The D.C. Circuit vacated an interim final rule issued by EPA that would allow manufacturers of heavy-duty diesel engines to pay nonconformance penalties in exchange for the right to sell engines that fail to satisfy nitrogen oxide requirements. In 2001, EPA issued a rule requiring a 95% reduction in...