EPA's Proposed Endangerment Finding For Aircraft Greenhouse Gas Emissions Opens Door To Additional Industry Regulation

On June 10, 2015, the United States Environmental Protection Agency ("EPA") proposed an endangerment finding that it calls "a preliminary but necessary first step to begin to address GHG emissions from the aviation sector" under the Clean Air Act ("CAA").1 EPA also issued an Advance Notice of Proposed Rulemaking ("ANPR"), proposing domestic adoption of the forthcoming International Civil Aviation Organization ("ICAO") rules, which are expected in February 2016. The proposed finding that greenhouse gas ("GHG") emissions from certain classes of aircraft engines contribute to climate change and endanger public health and welfare is in response to a citizen petition and exempts military and smaller aircraft, including most private aircraft. It is not clear from the finding whether EPA is seeking to regulate only domestic operators or whether it will also attempt to regulate international parties operating in the United States. While the Obama administration likely will not have time to promulgate regulations before leaving office, once EPA finalizes the endangerment finding, the CAA requires the new administration's EPA to issue standards of some kind regulating aircraft emissions from the identified classes of engines.

Path to Rulemaking

Before EPA can issue regulations under the CAA, the Administrator must make two preliminary determinations: first, she must find that GHGs endanger public health and welfare, and second, she must find that aircraft emissions cause or contribute to GHGs. The proposed aircraft endangerment finding relies on two recent GHG endangerment findings regarding automobiles2 and power plants3 from 2009 and 2014 respectively. In particular, the aircraft finding relies on the definition of "air pollution" taken from the 2009 automobile endangerment finding to support the determination that GHGs generally endanger human health and welfare. The automobile finding's analysis of health and welfare has been upheld in the face of repeated challenges, including by the U.S. Supreme Court in Massachusetts v. EPA.4

As for the second finding—that aviation causes or contributes to this danger—EPA cites data indicating that aviation is responsible for 3 percent of total GHGs in the United States and 11 percent of GHGs from the transportation sector. While the endangerment finding figures demonstrate that aviation is the largest unregulated source of GHGs in the transportation sector, they also indicate that in 2013, aircraft emitted less than one-seventh the amount of GHG emissions from automobiles, which constituted 23 percent of overall United States GHG emissions. According to data on EPA's website,5 power plants are responsible for more than 13 times the amount of carbon dioxide emissions as the aviation industry, as they make up 40 percent of total United States carbon dioxide emissions. Thus, the proposed aviation finding represents a continuing commitment by the agency to seek regulatory control over GHG emissions from diverse industries.

Rulemaking Process

Assuming the endangerment finding is finalized, which EPA anticipates will happen in 2016, the agency will begin the rulemaking processincluding mandated time for public commentbefore any standards are put in place. While a new presidential administration will likely be responsible for adopting the ultimate rule and may seek significant changes to the Obama administration's proposals, it is certain that there will be regulation of some kind. In Massachusetts v. EPA, the Supreme Court held that if EPA makes an endangerment finding, "the Clean Air Act requires the Agency to regulate emissions" regardless...