On December 20, 2016, Tennessee, through the Tennessee Department of Environment and Conservation (TDEC), submitted a request for the Environmental Protection Agency (EPA) to redesignate the Knoxville-Sevierville-La Follette, TN fine particulate matter (PM<INF>2.5</INF>) nonattainment area (hereinafter referred to as the "Knoxville Area" or "Area") to attainment for the 2006 24-hour PM<INF>2.5</INF> national ambient air quality standards (NAAQS) and to approve a state implementation plan (SIP) revision containing a maintenance plan and a reasonably available control measures (RACM) determination for the Area. EPA is approving Tennessee's RACM determination for the Knoxville Area and incorporating it into the SIP; approving Tennessee's plan for maintaining the 2006 24-hour PM<INF>2.5</INF> NAAQS for the Knoxville Area (maintenance plan), including the associated motor vehicle emission budgets (MVEBs) for nitrogen oxides (NO<INF>X</INF>) and direct PM<INF>2.5</INF> for the years 2014 and 2028, and incorporating it into the SIP; and redesignating the Knoxville Area to attainment for the 2006 24-hour PM<INF>2.5</INF> NAAQS.