National Lime Association v. Environmental Protection Agency

Pursuant to its obligations under § 111 of the Clean Air Act, the Environmental Protection Agency (EPA) (defendant) set new source performance standards (NSPS) regulating emissions from lime kilns. NSPS were technology-based standards for new air-pollution sources. Before determining appropriate standards, the EPA visited 39 plants that manufactured or hydrated lime and conducted testing of emissions at six of those sites. Based on this testing, the EPA set NSPS that limited the mass of particulate that could be emitted and the permitted visibility of exhaust gas emissions from all lime-hydrating and certain lime-manufacturing facilities. Section 111 required that the emission-control system specified in the NSPS be adequately demonstrated and the emission standards themselves be achievable using the specified system. Factors such as variations in feedstock, gas velocity in the kiln, level of capacity at which a plant was operating, particle size, and the amount of dust generated impacted the effectiveness of emissions-control systems. The EPA acknowledged that the standards must be able to be met in all operating conditions nationwide but did not establish in the record that the six sites that formed the basis of its conclusions as to achievable limits were a representative sampling of all the types of facilities that would be covered by the NSPS. Of the six test sites, three could consistently meet the standards the EPA set. National Lime Association (NLA) (plaintiff), a trade group representing 90 percent of the industry, challenged the NSPS, arguing that the administrative record contained inadequate factual support that the specified standard was achievable. The court of appeals had original jurisdiction over the petition.