Natural Resources Defense Council, Inc. v. United States Environmental Protection Agency

Pursuant to the Clean Air Act, the Environmental Protection Agency (“EPA”) regulates emissions of particles known as particulate matter. In order to meet statutory and regulatory requirements, California submitted a state implementation plan (“SIP”) to the EPA for its approval. The SIP contains, among many other things, limits on motor vehicle emissions for the years 2009 and 2012. Although the EPA’s overall approval process of the SIP is still underway, the agency has made a preliminary finding that the SIP’s limits on motor vehicle emissions for years 2009 and 2012 are adequate for purposes of the state’s transportation plans and projects. The EPA’s adequacy determination allows California to approve transportation plans and projects that otherwise could not proceed. Pursuant to 42 U.S.C. § 7607 (b)(1), several environmental groups filed this petition for review. Petitioners assert that the EPA’s adequacy determination was arbitrary, capricious, or otherwise contrary to law. We deny the petition.

FACTUAL AND PROCEDURAL HISTORY

A. Air Quality Standards and State Implementation Plans

The general statutory background concerning ah’ quality standards and SIPs is common…