Approval and Promulgation of Implementation Plans and Designation of Areas for Air Quality Planning Purposes; Michigan; Redesignation of the Allegan County Areas to Attainment for Ozone

EPA is approving Michigan's request to redesignate the Allegan County, Michigan nonattainment area to attainment for the 1997 8-hour ozone standard because the request meets the statutory requirements for redesignation under the Clean Air Act (CAA). The Michigan Department of Natural Resources and Environment (MDNRE) submitted this request on May 12, 2010, and supplemented it on June 16, 2010. This approval involves several related actions. EPA is making a determination under the CAA that the Allegan County area has attained the 1997 8-hour ozone National Ambient Air Quality Standard (NAAQS). This determination is based on three years of complete, quality-assured and certified ambient air quality monitoring data for the 2007-2009 ozone seasons that demonstrate that the 8-hour ozone NAAQS has been attained in the area. Preliminary data available for 2010 is consistent with continued attainment. EPA is also approving, as a revision to the Michigan State Implementation Plan (SIP), the State's plan for maintaining the 8-hour ozone NAAQS through 2021 in the area. EPA is approving the 2005 emissions inventory submitted with the redesignation request as meeting the comprehensive emissions inventory requirement of the CAA for the Allegan County area. Finally, EPA found adequate and is approving the State's 2021 Motor Vehicle Emission Budgets (MVEBs) for the Allegan County area.