The Environmental Protection Agency (EPA) is taking final action to approve a revision to the South Carolina State Implementation Plan (SIP), submitted by the South Carolina Department of Health and Environmental Control (DHEC), on December 7, 2016, addressing the Clean Air Act (CAA) interstate transport (prongs 1 and 2) infrastructure SIP requirements for the 2010 1-hour Nitrogen Dioxide (NO<INF>2</INF>) National Ambient Air Quality Standard (NAAQS). The CAA requires that each state adopt and submit a SIP for the implementation, maintenance, and enforcement of each NAAQS promulgated by EPA, commonly referred to as an "infrastructure SIP." Specifically, EPA is taking final action to approve South Carolina's December 7, 2016, SIP submission addressing prongs 1 and 2 to ensure that air emissions in the State do not significantly contribute to nonattainment or interfere with maintenance of the 2010 1-hour NO<INF>2</INF> NAAQS in any other state.