Utility Air Regulatory Group v. Environmental Protection Agency

Acting under the Clean Air Act, the Environmental Protection Agency (EPA) (defendant) adopted the Regional Haze Rule (rule) to restore the air quality and visibility in certain national parks and wilderness areas (Class I areas). The rule required states to impose best available retrofit technology (BART) on certain pollution sources, usually electric generation plants. However, the rule also allowed states to instead adopt alternative approaches provided they met the EPA’s better-than-BART standard. The EPA concluded that the requirements of its Cross-State Air Pollution Rule (CSAPR), an emissions-control program, were stringent enough to make compliance with CSAPR a better-than-BART alternative. Consequently, states participating in CSAPR were excused from complying with BART itself. The National Parks Conservation Association and others (conservationists) (plaintiffs) challenged that EPA determination. They argued that because CSAPR was promulgated under a different section of the Clean Air Act, it would take effect regardless of BART. Consequently, the EPA needed to consider the reduction in emissions that would be achieved by CSAPR and BART combined versus the reduction that would be achieved by CSAPR alone to determine whether CSAPR constituted a better-than-BART alternative. In conjunction with adopting the rule amendment, the EPA also disapproved certain state implementation plans (SIPs) that relied on the Clean Air Interstate Rule (CAIR), a predecessor to CSAPR that had been overturned. The EPA issued federal implementation plans that would apply in the disapproved states until the states came up with new plans that incorporated CSAPR. Utility Air Regulatory Group, certain states, and others (industry and state parties) challenged the EPA’s disapproval of the SIPs, arguing that even though CAIR itself was no longer effective, if meeting CAIR’s requirements constituted a better-than-BART alternative in prior years, then it must still be considered a better-than-BART alternative. The court of appeals considered the challenges raised by the conservationists and the industry and state parties.