Air Pollution Control District of Jefferson County v. Environmental Protection Agency

Jefferson County, Kentucky, and Floyd County, Indiana, shared a boundary on the Ohio River. Jefferson County and Floyd County drew on the same air resources and thus were designated, along with Clark County, Indiana, as the Louisville Interstate Air Quality Control Region. Each county was subject to the implementation plan adopted by its respective state. Initially, Indiana and Kentucky had adopted identical emission limitations for sulfur dioxide (SO2). In 1973, Indiana’s state implementation plan (SIP) set an emission limitation for the Gallagher Power Station. The Gallagher Power Station was located near the Indiana–Kentucky border and was the largest producer of SO2 in Floyd County. In 1974, Indiana adopted new SO2 regulations that exempted the Gallagher Power Station from emission limitations. The Environmental Protection Agency (EPA) (defendant) approved the exemption because it would not interfere with the attainment and maintenance standards in either Indiana or Kentucky. Jefferson County had strict SO2 emission limitations but was unable to attain the National Ambient Air Quality Standard (NAAQS) for SO2. In 1979, the Air Pollution Control District of Jefferson County (plaintiff) filed a Section 126 petition for interstate pollution abatement under the Clean Air Act, requesting that the EPA find that SO2 emissions from the Gallagher Power Station were preventing the attainment and maintenance of the NAAQSs for SO2 in Jefferson County and that the emissions from the Gallagher Power Station would prevent Jefferson County from preventing deterioration of air quality once attainment is reached. The EPA calculated that only about 3 percent of the SO2 concentration in areas in Jefferson County that were not in attainment with the NAAQSs were attributable to the Gallagher Power Site. The EPA denied Jefferson County’s Section 126 petition, concluding that the Gallagher Power Station does not cause or substantially contribute to a violation of the SO2 NAAQS.