Approval and Promulgation of Air Quality Implementation Plans, Ohio and Indiana; Redesignation of the Ohio and Indiana Portions Cincinnati-Hamilton Area to Attainment of the 1997 Annual Standard for Fine Particulate Matter

EPA is approving, under the Clean Air Act (CAA), Ohio's and Indiana's requests to redesignate their respective portions of the Cincinnati-Hamilton nonattainment area (for Ohio: Butler, Clermont, Hamilton, and Warren Counties, Ohio; for IN: a portion of Dearborn County) to attainment for the 1997 annual National Ambient Air Quality Standard (NAAQS or standard) for fine particulate matter (PM<INF>2.5</INF>). The Ohio Environmental Protection Agency (Ohio EPA) submitted its request on December 9, 2010, and the Indiana Department of Environmental Management (IDEM) submitted its request on January 25, 2011. Kentucky's request to redesignate its portion of the Cincinnati-Hamilton area, submitted to EPA on January 27, 2011, will be addressed in a separate rulemaking action. EPA's approvals here involve several additional related actions. EPA has determined that the entire Cincinnati-Hamilton area has attained the 1997 annual PM<INF>2.5</INF> standard. EPA is approving, as revisions to the Ohio and Indiana State Implementation Plans (SIPs), the states' plans for maintaining the 1997 annual PM<INF>2.5</INF> NAAQS through 2021 in the area. EPA is approving the 2005 emissions inventories for the Ohio and Indiana portions of the Cincinnati-Hamilton area as meeting the comprehensive emissions inventory requirement of the CAA. Finally, EPA finds adequate and is approving Ohio and Indiana's Nitrogen Oxides (NO<INF>X</INF>) and PM<INF>2.5</INF> Motor Vehicle Emission Budgets (MVEBs) for 2015 and 2021 for the Cincinnati-Hamilton area.