The Nickel Report

As we have discussed previously, the federal Clean Air Act (CAA) addresses what is often termed “interstate transport.” That is the phenomenon in which emissions from factories, power plants, motor vehicles and many other emission sources are transported by prevailing winds across state lines, sometimes over great distances. The CAA looks to states, first and foremost, to include control measures in implementation plans to reduce emissions that travel into other states. The statutory objective is to prohibit “significant contributions” by upwind states to violations of national ambient air quality standards (NAAQS) in downwind states. Although states have primary responsibility, EPA sometimes has invoked its CAA authority to establish federally enforceable requirements to address significant contributions when it concludes upwind states have not taken sufficient steps. In 2016, EPA adopted its most recent set of regulatory interstate transport controls in a rulemaking action called the “Cross-State Air Pollution Rule Update”—or the “CSAPR Update” for short. On September 13, the US Court of Appeals for the DC Circuit issued a decision in closely-watched litigation involving challenges to the CSAPR Update. (The case is Wisconsin v. EPA, No. 16-1406.) While upholding this EPA regulation in most respects, the court ruled in favor of a challenge that concerns the timing of upwind-state emission controls.

The phrase “interstate transport” conjures images of planes, trains and trucks carrying people and goods cross-country. But, under the federal Clean Air Act (CAA), the term is often used to refer to interstate air pollution—emissions from factories, power plants, motor vehicles, refineries and other sources that are transported by prevailing winds across state lines, sometimes over hundreds of miles. The interstate transport phenomenon often has posed for the US Environmental Protection Agency (EPA) what the Supreme Court has called “a thorny causation problem: How should EPA allocate among multiple contributing upwind States responsibility for a downwind State’s excess pollution?” EPA v. EME Homer City Generation, L.P., 134 S. Ct. 1584, 1604 (2014). EPA’s efforts to address this issue have yielded, over the last two decades, a series of complex federal regulatory programs imposing increasingly stringent controls on emissions in most states in the eastern half of the country—first the “NOx SIP Call” rule in 1998, then the Clean Air Interstate Rule in 2005, followed by the Cross-State Air Pollution Rule (CSAPR) in 2011 and, most recently, the 2016 “CSAPR Update” rule. Now, however, EPA, while vigorously defending the CSAPR Update rule against pending litigation challenges, is signaling a fresh approach for potential future interstate transport regulation, an approach that may involve greater deference to states’ analyses and determinations and that may eschew additional broad regulatory mandates imposed by EPA.

2018 is turning out to be a banner year for nationally applicable developments—both judicial and administrative—with regard to National Ambient Air Quality Standards (“NAAQS” or “Standards”) for ozone. As the year began, EPA was proceeding with implementation of the ozone NAAQS that it set in 1997 and 2008 in accordance with a rule that it had promulgated in 2015 describing requirements for State Implementation Plans (SIPs) and the transition from the 1997 NAAQS to the more stringent 2008 one. 80 Fed. Reg. 12264 (Mar. 6, 2015) (2015 SRR). The Trump administration was reviewing the prior administration’s 2015 decision further tightening the NAAQS to determine whether those more stringent NAAQS should be maintained, modified or reconsidered. To allow the Trump administration to complete that review, the DC Circuit placed in abeyance litigation challenging the 2015 Standards as either too stringent or too lenient. Murray Energy v. EPA, No. 15-1385 (D.C. Cir. Oct. 26, 2015). EPA had designated most of the country attainment/unclassifiable for the 2015 NAAQS, but had not made designations for other areas. 82 Fed. Reg. 54232 (Nov. 16, 2017).