Approval and Promulgation of State Implementation Plans: Alaska; Anchorage Carbon Monoxide Limited Maintenance Plan and State Implementation Plan Revisions

The State of Alaska (the State) submitted two State Implementation Plan (SIP) revisions to the Anchorage Transportation Control Program, Anchorage Carbon Monoxide (CO) Maintenance Plan. On September 20, 2011, the State submitted a SIP revision (2011 Submittal) that updated Anchorage's CO motor vehicle emissions budget (MVEB) in the Anchorage CO maintenance area using the EPA's Motor Vehicle Emission Simulator (MOVES) model. On April 22, 2013, the State submitted a SIP revision (2013 Submittal) to satisfy the Clean Air Act (CAA) section 175A(b) requirement for a second 10-year maintenance plan for the Anchorage CO maintenance area in the form of a limited maintenance plan (LMP). This LMP addresses maintenance of the CO National Ambient Air Quality Standards (NAAQS) for a second 10-year period, beyond redesignation of the area to attainment, through 2024. The EPA is taking direct final action to approve both the 2013 Submittal and portions of the 2011 Submittal that are not superseded by the 2013 Submittal. The EPA is approving these SIP revisions because the State has demonstrated that they are consistent with the CAA.