Adequacy Status of the Knoxville, TN 2006 24-Hour PM2.5

The U.S. Environmental Protection Agency (EPA) is notifying the public that it has found that the motor vehicle emissions budgets (MVEBs) contained in the State Implementation Plan (SIP) revision pertaining to the Knoxville, Tennessee 2006 24-hour fine particulate matter (PM2.5) nonattainment area adequate for transportation conformity purposes. This SIP revision was submitted to EPA on December 20, 2016, by the Tennessee Department of Environment and Conservation (TDEC) and requests that EPA redesignate the area to attainment for the 2006 24-hour PM2.5 national ambient air quality standards (NAAQS), and that EPA approve a maintenance plan for the continued attainment of the Area. Knoxville's 2006 24-hour PM2.5 nonattainment area (hereafter referred to as ``the Knoxville Area''), for which MVEBs are established in this notice, is comprised of the entire counties of Anderson, Blount, Knox, and Loudon, as well as a portion of Roane County. On March 2, 1999, the United States Court of Appeals for the District of Columbia Circuit (D.C. Circuit) ruled that submitted SIPs cannot be used for transportation conformity determinations until EPA has affirmatively found that the MVEBs are adequate. As a result of EPA's finding, the Knoxville Area must use the MVEBs for future conformity determinations for 2006 24- hour PM2.5 NAAQS.