EPA is approving a State Implementation Plan (SIP) revision submitted by the State of Ohio which allows the State to discontinue the vehicle inspection and maintenance (I/M) program in the Cincinnati- Hamilton and Dayton-Springfield areas, also known as the E-Check program. The revision specifically requests that the E-Check program regulations be moved from the active control measures portion of the SIP to the contingency measures portion of the Cincinnati-Hamilton and Dayton-Springfield ozone maintenance plans. The Ohio Environmental Protection Agency (Ohio EPA) submitted this request on April 4, 2005, and supplemented it on May 20, 2005, February 14, 2006, May 9, 2006, October 6, 2006, and February 19, 2008. EPA is approving Ohio's request because the State has demonstrated that discontinuing the I/M program in the Cincinnati-Hamilton and Dayton-Springfield areas will not interfere with the attainment and maintenance of the 8-hour ozone National Ambient Air Quality Standard (NAAQS) and the fine particulate NAAQS or with the attainment and maintenance of other air quality standards.