Skip to Content


Adequacy Status of the Knoxville, TN 1997 Annual PM2.5

Document Details

Information about this document as published in the Federal Register.

Published Document

This document has been published in the Federal Register. Use the PDF linked in the document sidebar for the official electronic format.

Start Preamble


Environmental Protection Agency.


Notice of adequacy.


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 1997 Annual fine particulate matter (PM2.5) nonattainment area are adequate for transportation conformity purposes. This SIP revision was submitted on December 20, 2016, by the Tennessee Department of Environment and Conservation (TDEC) and requests that EPA redesignate the area to attainment for the 1997 annual PM2.5 national ambient air quality standards (NAAQS), and that EPA approve a maintenance plan for the continued attainment of the Area. The Knoxville 1997 Annual 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 the 1997 Annual PM2.5 NAAQS.


These MVEBs are effective March 27, 2017.

Start Further Info


Kelly Sheckler, U.S. Environmental Protection Agency, Region 4, Air Regulatory Management Section, 61 Forsyth Street SW., Atlanta, Georgia 30303. Ms. Sheckler can also be reached by telephone at (404) 562-9222, or via electronic mail at The finding is available at EPA's conformity Web site:​otaq/​stateresources/​transconf/​currsips.htm.

End Further Info End Preamble Start Supplemental Information


This notice is simply an announcement of a finding that EPA has already made. EPA, Region 4, sent a letter to TDEC on February 15, 2017, stating that the MVEBs identified for Knoxville in Tennessee's maintenance SIP revision, submitted on December 20, 2016, are adequate and must be used for transportation conformity determinations in the Knoxville Area.

EPA posted the availability of the Knoxville Area MVEBs on EPA's Web site on December 22, 2016, as part of the adequacy process, for the purpose of soliciting comments. The adequacy comment period ran until January 23, 2017. During EPA's adequacy comment period, no comments were received on the Knoxville Area MVEBs. Through this notice, EPA is informing the public that these MVEBs are adequate for transportation conformity. This finding has also been announced on EPA's conformity Web site:​otaq/​stateresources/​Start Printed Page 13338transconf/​pastsips.htm. The adequate MVEBs are provided in Table 1 below:

Table 1—Knoxville, Tennessee 1997 Annual PM2.5 MVEBS

[Tons per year or tpy]

PM2.5444.78* 245.00
NOX15,597.73* 7,171.14
* This includes a safety margin of 10.39 tpy for PM2.5 and 2,613.27 tpy for NOX in 2028.

Transportation conformity is required by section 176(c) of the Clean Air Act. EPA's conformity rule, 40 CFR part 93, requires that transportation plans, programs, and projects conform to state air quality implementation plans and establishes the criteria and procedures for determining whether or not they do so. Conformity to a SIP means that transportation activities will not produce new air quality violations, worsen existing violations, or delay timely attainment of the NAAQS.

The criteria by which EPA determines whether a SIP's MVEBs are adequate for transportation conformity purposes are outlined in 40 CFR 93.118(e)(4). We have also described the process for determining the adequacy of submitted SIP budgets in our July 1, 2004 (69 FR 40004), final rulemaking entitled, “Transportation Conformity Rule Amendments for the New 8-Hour Ozone and PM2.5 National Ambient Air Quality Standards and Miscellaneous Revisions for Existing Areas; Transportation Conformity Rule Amendments: Response to Court Decision and Additional Rule Changes.” Please note that an adequacy review is separate from EPA's completeness review, and it should not be used to prejudge EPA's ultimate approval of Tennessee's 1997 Annual PM2.5 SIP revision for the Knoxville Area. Even if EPA finds a budget adequate, the SIP revision could later be disapproved.

Within 24 months from the effective date of this notice or until such time that the 1997 PM2.5 NAAQS is revoked for the Knoxville Area, the transportation partners will need to demonstrate conformity to the new MVEBs, if the demonstration has not already been made, pursuant to 40 CFR 93.104(e). See 73 FR 4419 (January 24, 2008).

Start Authority

Authority: 42 U.S.C. 7401 et seq.

End Authority Start Signature

Dated: February 15, 2017.

Kenneth R. Lapierre,

Acting Regional Administrator, Region 4.

End Signature End Supplemental Information

[FR Doc. 2017-04681 Filed 3-9-17; 8:45 am]