The Environmental Protection Agency (EPA) is taking final action to approve portions of State Implementation Plan (SIP) revisions provided by the State of North Carolina through the North Carolina Division of Air Quality (NCDAQ) in letters dated June 5, 2017, and August 22, 2017. The submissions revise several regulations concerning nitrogen oxides (NO<INF>X</INF>), emission control standards, monitoring, and reporting requirements. EPA is taking final action to approve these provisions of the SIP revisions because these changes are consistent with the Clean Air Act (CAA or Act) and federal regulations.