Determination of Attainment, Approval and Promulgation of Implementation Plans and Designation of Areas for Air Quality Planning Purposes; Ohio; Redesignation of the Dayton-Springfield 8-Hour Ozone Nonattainment Area to Attainment

The Ohio Environmental Protection Agency (Ohio EPA) submitted a request on November 6, 2006, and supplemented it on November 29, 2006, December 4, 2006, December 13, 2006, January 11, 2007, March 9, 2007, March 27, 2007, and May 31, 2007, for redesignation of the Dayton-Springfield, Ohio area (Clark, Greene, Miami, and Montgomery Counties) to attainment for the 8-hour ozone standard. On June 20, 2007, EPA proposed to approve this submission. EPA provided a 30-day review and comment period. The comment period closed on July 20, 2007. EPA received one comment in favor of redesignation from the Dayton area Regional Air Pollution Control Agency. Today, EPA is approving Ohio's request and the associated plan for continuing to attain the standard. As part of this action, EPA is making a determination that the Dayton- Springfield 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 2004-2006 ozone seasons that demonstrate that the 8-hour ozone NAAQS has been attained in the area. Preliminary 2007 air quality data show that the area continues to attain the 8-hour ozone standard. EPA is approving the maintenance plan for this area and is redesignating the area to attainment. Finally, EPA is approving, for purposes of transportation conformity, the motor vehicle emission budgets (MVEBs) for the years 2005 and 2018.