Air Plan Approval and Air Quality Designation; TN; Redesignation of the Knoxville 1997 Annual PM2.5

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, Tennessee fine particulate matter (PM2.5) nonattainment area (hereinafter referred to as the ``Knoxville Area'' or ``Area'') to attainment for the 1997 Annual PM2.5 national ambient air quality standards (NAAQS) and to approve a state implementation plan (SIP) revision containing a maintenance plan, a reasonably available control measures (RACM) determination, and source- specific requirements for the Area. EPA is approving Tennessee's RACM determination for the Knoxville Area and incorporating it into the SIP; incorporating source-specific requirements for two sources in the Area into the SIP; determining that the Knoxville Area is attaining the 1997 Annual PM2.5 NAAQS based on 2013-2015 data; approving Tennessee's plan for maintaining the 1997 Annual PM2.5 NAAQS for the Knoxville Area (maintenance plan), including the associated motor vehicle emission budgets (MVEBs) for nitrogen oxides (NOX) and direct PM2.5 for the years 2014 and 2028, and incorporating it into the SIP; and redesignating the Knoxville Area to attainment for the 1997 Annual PM2.5 NAAQS.