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

Samenvatting

EPA is proposing to approve Michigan's request to redesignate the Allegan County, Michigan 8-hour ozone 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 24, 2010 and supplemented it on June 16, 2010. This proposed approval involves several related actions. EPA is proposing to determine that the Allegan County area has attained the 8- hour ozone National Ambient Air Quality Standard (NAAQS). This determination is based on three years of complete, quality-assured 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 proposing to approve, 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 proposing to approve the 2005 emissions inventory submitted with the redesignation request as meeting the