A district court held that reheater replacements at a Louisiana power plant constitute a major modification and do not qualify for the routine maintenance, repair or replacement exception to the…

The D.C. Circuit vacated 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…

The D.C. Circuit held that trade associations for the engine, petroleum, and food industries lack standing to challenge two EPA decisions approving the introduction of E15—a blend of gasoline and…

The Fifth Circuit vacated EPA's disapproval of Texas's flexible permit program under the CAA. Texas submitted the program to EPA as a revision to its SIP and as a new feature of the…

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…

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…

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,…

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…

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…

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…