Environmental Protection Agency (EPA) is approving in part and disapproving in part State Implementation Plan (SIP) revisions submitted by the State of Nevada pursuant to the requirements of the Clean Air Act (CAA) for the 2008 ozone national ambient air quality standards (NAAQS), the 2010 nitrogen dioxide (NO<INF>2</INF>) NAAQS and the 2010 sulfur dioxide (SO<INF>2</INF>) NAAQS. The CAA requires that each state adopt and submit a SIP for the implementation, maintenance, and enforcement of each NAAQS promulgated by the EPA, and that EPA act on such SIPs. Nevada has met most of the applicable requirements. Where EPA is disapproving, in part, Nevada's SIP revisions, the deficiencies have already been addressed by a federal implementation plan (FIP).