EPA is taking direct final action to approve revisions to the Maryland State Implementation Plan (SIP) submitted by the Maryland Department of the Environment (MDE) on June 30, 2009. The revisions amend the visible emissions requirements of the Maryland SIP's regulation for the Control of Iron and Steel Production Installations only as they apply to sintering plants. The sintering plant located at the Sparrows Point steelmaking facility (Sparrows Point) is the only sintering plant located in the State of Maryland. The revisions exempt the sintering plant from the visible emissions section of the regulation for the Control of Iron and Steel Production Installations contingent upon the source's two wet scrubbers, used to control emissions of particulate matter, continuously monitoring compliance with specified pressure drop and flow rate operating parameters. EPA is approving these revisions because they provide for a continuous means of determining compliance with the applicable SIP emission rate for particulate matter from the sintering plant located at Sparrows Point, and because that emission rate has been demonstrated to protect and maintain the National Ambient Air Quality Standards (NAAQS) for PM<INF>10</INF> (particulate matter consisting of particles with an aerodynamic diameter less than or equal to 10 micrometers). EPA is approving these revisions in accordance with the requirements of the Clean Air Act (CAA).