On July 11, 2008 the U.S. Environmental Protection Agency (EPA) released an Advance Notice of Proposed Rulemaking (ANPR) in response to the U.S. Supreme Court’s April 2007 decision in Massachusetts v. EPA, 549 U.S. 497 (2007). In Massachusetts, the Court ruled that greenhouse gases (carbon dioxide, methane, nitrous oxide and hydrofluorocarbons) satisfy the Clean Air Act’s (CAA) definition of “air pollutant,” and thus can be regulated under the CAA if the EPA finds that greenhouse gas emissions constitute an “endangerment” to public health or welfare.

The ANPR does not make an “endangerment” finding. Rather, it explores how existing programs under the CAA may be used to regulate greenhouse gases and solicits public comment regarding the effects of climate change and the potential consequences of regulating greenhouse gas emissions under the CAA. The EPA sets forth numerous problems with regulating greenhouse gases under the existing CAA, and requests public comment on many issues, among them:

  • Whether to define the six primary greenhouse gases as “air pollution” collectively or individually;
  • Whether to regulate or address air constituents outside of the six greenhouse gases, such as water vapor;
  • How to determine the baseline emissions of greenhouse gases in order to assess what constitutes an “endangerment” going forward;
  • Consideration of how possible future climate legislation in Congress would affect regulation under the CAA;
  • Suggestions regarding potential regulatory approaches and technologies for reducing greenhouse gas emissions;
  • Possible effects on the economy by regulating greenhouse gases under the CAA; and
  • Whether and how market-based regulatory approaches, such as cap-and-trade, could be utilized to regulate greenhouse gases.

Regulation by the EPA under the CAA in this area could potentially have a significant effect on many sectors of the economy, and could expand the EPA’s regulatory authority in an unprecedented way. This is why the EPA appears reluctant to regulate greenhouse gases under the CAA, and states that the CAA is “ill-suited for the task of regulating global greenhouse gases.” The EPA believes Congress should pass new climate change legislation in order to avoid regulation under the CAA.

The ANPR can be found on the EPA website here: www.epa.gov/climatechange/anpr.html.  Interested parties should closely monitor developments during the public comment period and make their views and concerns known to the EPA. The EPA accepts comments on the ANPR for 120 days following publication in the Federal Register; however, as of the date of this posting, the ANPR had not yet been officially published in the Federal Register.