Davis

Opinion by Judge CANBY; Opinion concurring in part and dissenting in part by Judge O’SCANNLAIN.

California Governor Gray Davis and the California Air Resources Board (“CARB”) (collectively “California”) petition for review of an order of the United States Environmental Protection Agency (“EPA”) denying their request for a waiver of the oxygen level requirement under the federal reformulated gasoline program. The EPA denied the waiver on the ground that California had not clearly demonstrated that a waiver would have a beneficial effect on ozone pollution, and ruled that it was unnecessary to consider the effect a waiver would have on particulate matter pollution. We conclude that the EPA abused its discretion in refusing to consider and weigh the effect of the proposed waiver on particulate matter pollution along with its effect on ozone levels. We accordingly grant the petition for review, vacate the EPA’s order, and remand for further proceedings. We reject, however, California’s other technical and procedural challenges to the EPA’s action.

FACTS AND AGENCY PROCEEDINGS

The Clean Air Act

The Clean Air Act, 42 U.S.C. §§ 7401 -7671q, authorizes the EPA to set attainment…

concurring in part and dissenting in part:

I agree that the United States Environmental Protection Agency’s (“EPA’s”) interpretation of 42 U.S.C. § 7545 (k)(2)(B) is afforded broad deference. As a result, I concur in Parts 1A, IB, 2, and 3 of the majority’s opinion, which hold that the EPA’s extensive review of gasoline emissions data is neither arbitrary nor capricious, and that any disagreement that California has with the EPA’s scientific analysis is simply insufficient to support its petition for review. I must dissent, *981 however, from the majority’s further conclusion in Part 1C that the agency’s assessment of potential ozone effects, while failing to consider particulate matter (“PM”) effects, somehow contravenes congressional intent.

In subsection (k)(2)(B), Congress imposed a 2.0 percent oxygen content requirement for gasoline used in prescribed high-smog zone areas of the country. In the case before us, the State of California sought an exemption from such requirement, claiming that without a waiver, it would be hard pressed to meet certain federal air quality standards. The Administrator denied the waiver request, concluding that California had failed to demonstrate…