Air Plan Approval; NC; Great Smoky Mountains National Park, Raleigh-Durham-Chapel Hill and Rocky Mount Areas Limited Maintenance Plans for the 1997 8-Hour Ozone NAAQS

The Environmental Protection Agency (EPA) is taking final action to approve state implementation plan (SIP) revisions submitted by the State of North Carolina, through the North Carolina Department of Environment and Natural Resources, Division of Air Quality (NCDAQ), in a letter dated September 22, 2020. The SIP revisions include the 1997 8-hour ozone national ambient air quality standards (NAAQS) Limited Maintenance Plans (LMPs) for the Great Smoky Mountains National Park (GSMNP), Raleigh-Durham-Chapel Hill (Triangle) and Rocky Mount, North Carolina Areas (collectively, "Areas"). EPA is finalizing approval of the LMPs for the Areas because each LMP provides for the maintenance of the 1997 8-hour ozone NAAQS within each of the Areas through the end of the second 10-year portion of the maintenance period. This action makes certain commitments related to maintenance of the 1997 8-hour ozone NAAQS in the Areas federally-enforceable as part of the North Carolina SIP.