EPA is approving a request submitted by the Ohio Environmental Protection Agency (Ohio EPA) on August 22, 2008, to revise the Ohio State Implementation Plan (SIP) under the Clean Air Act (CAA). The State has submitted revisions to twelve rules and rescinded one rule in Ohio Administrative Code (OAC) Chapter 3745-17, "Particulate Matter Standards." The revisions were submitted by Ohio EPA to satisfy the State's 5-year review requirements. The particulate matter (PM) standards contain the particulate emission control requirements that have been necessary to attain and maintain the 2006 National Ambient Air Quality Standards (NAAQS) for PM in the State. EPA is approving the revisions to nine of the OAC 3745-17 rules. EPA is approving only a portion of Rule 7, while not acting on the portion providing a partial exemption from opacity limits for a lime kiln in Woodville, Ohio. We are conditionally approving Rule 11 based on a commitment by Ohio to address EPA's concerns with the large item size exemptions. EPA is not acting on Rule 3, regarding opacity measurement methods. Lastly, EPA is approving the rescission of Rule 5 from the Ohio SIP.