EPA is taking direct final action to approve revisions to the Maryland State Implementation Plan (SIP). The revision, State of Maryland SIP Revision <greek-i>05-08, replaces the current SIP requirements for the control of carbon monoxide (CO) emissions from basic oxygen furnaces (BOFs) at steel mills in the State of Maryland with a new, equivalent CO standard. EPA is approving this revision to the Maryland SIP in accordance with the requirements of the Clean Air Act (CAA).