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Adequacy Status of the Hickory-Morganton-Lenoir, North Carolina 1997 PM2.5

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Environmental Protection Agency (EPA).


Notice of adequacy.


In this notice, EPA is notifying the public of its finding that the nitrogen oxides (NOx) motor vehicle emissions budget (MVEB) in the Hickory-Morganton-Lenoir, North Carolina (hereafter referred to as the Hickory Area) attainment demonstration for the 1997 PM2.5 standard, submitted on August 21, 2009, by the North Carolina Department of Environment and Natural Resources (NCDENR), is adequate for transportation conformity purposes. EPA is also making an insignificance finding for direct particulate matter (PM) through the transportation conformity adequacy process for the Hickory Area. The Hickory Area is comprised of the entire county of Catawba in North Carolina. On March 2, 1999, the District of Columbia Circuit Court ruled that submitted state implementation plans (SIPs) cannot be used for transportation conformity determinations until EPA has affirmatively found them adequate. As a result of EPA's finding, the Hickory Area must use the NOX MVEB from the submitted Hickory, North Carolina 1997 PM2.5 attainment demonstration for future conformity determinations, and the Hickory Area is not required to perform a regional emissions analysis for direct PM2.5 in future PM2.5 transportation conformity determinations for the 1997 annual PM2.5 standard.


The adequacy finding for the NOX MVEB and the insignificance finding for direct PM2.5 are effective March 16, 2010.

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Amanetta Somerville, Environmental Scientist, U.S. Environmental Protection Agency, Region 4, Air Planning Branch, Air Quality Modeling and Transportation Section, 61 Forsyth Street, SW., Atlanta, Georgia 30303. Ms. Somerville can also be reached by telephone at (404) 562-9025, or via electronic mail at The finding is available at EPA's conformity Web site:​otaq/​transp.htm (once there, click on the “Transportation Conformity” text icon, then look for “Adequacy Review of SIP Submissions”).

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Today's notice is simply an announcement of findings that EPA has already made. EPA Region 4 sent a letter to NCDENR on January 20, 2010, stating that the 2009 NOX MVEB in the 1997 PM2.5 attainment demonstration for Hickory, dated August 21, 2009, is adequate. The letter also states that direct PM2.5 is insignificant for the Hickory Area, therefore no regional emissions analysis is required. EPA posted the availability of the Hickory Area MVEB and insignificance demonstration on EPA's Web site on September 8, 2009, as part of the adequacy process, for the purpose of soliciting comments. The comment period ran from September 8, 2009, through October 8, 2009. EPA's findings have also been announced on EPA's conformity Web site:​otaq/​stateresources/​index.htm (once there, click “Transportation Conformity” text icon, then look for “Adequacy Review of SIP Start Printed Page 9205Submissions”). The adequate NOX MVEB is provided in the following table:

Hickory Area NOX MVEB

[kilograms per day]

Catawba County2,887,955

Transportation conformity is required by section 176(c) of the Clean Air Act, as amended in 1990. EPA's conformity rule 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. Conformity to a SIP means that transportation activities will not produce new air quality violations, worsen existing violations, or delay timely attainment of the national ambient air quality standards (NAAQS).

The criteria by which EPA determines whether a SIP's MVEB is adequate for transportation conformity purposes are outlined in 40 Code of Federal Regulations (CFR) 93.118(e)(4). Additionally, the criteria by which EPA determines whether a particular pollutant/precursor is an insignificant contributor to the air quality problem in an area can be found at 40 CFR 93.109(k). Insignificance findings are based on a number of factors, including the percentage of motor vehicle emissions in context of the total SIP inventory, the current state of air quality as determined by monitoring data for that NAAQS, the absence of SIP motor vehicle control measures, and historical trends and future projections of the growth of motor vehicle emissions. EPA's rationale for the allowance of insignificance findings can be found in the July 1, 2004, revision to the transportation conformity rule at 69 Federal Register (FR) 40004. Specifically, the rationale is explained on page 40061 under the subsection entitled “B. Areas With Insignificant Motor Vehicle Emissions.” Please note that an adequacy review is separate from EPA's completeness review, and it also should not be used to prejudge EPA's ultimate approval of the SIP. Even if EPA finds the MVEB adequate or makes an insignificance finding through the adequacy process, the Agency may later disapprove the SIP.

EPA has described the process for determining the adequacy of submitted SIP budgets in a May 14, 1999, memorandum entitled “Conformity Guidance on Implementation of March 2, 1999 Conformity Court Decision.” EPA has followed this guidance in making this adequacy determination. This guidance is incorporated into EPA's July 1, 2004, 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” (69 FR 40004).

Within 24 months from the effective date of this notice, the transportation partners will need to demonstrate conformity to the new MVEB if the demonstration has not already been made, pursuant to 40 CFR 93.104(e). (See 73 FR 4419 (January 24, 2008).)

Additionally, the Transportation Conformity Rule at 40 CFR 93.109(k) states that a regional emissions analysis is no longer necessary for direct PM2.5 if EPA finds, through the adequacy or approval process, that regional motor vehicle emissions are an insignificant contributor to the air quality problem for that pollutant/precursor as demonstrated in the SIP. The insignificance finding should be noted in all future conformity determinations, and does not relieve the area of meeting all other transportation conformity requirements.

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

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Dated: February 17, 2010.

Beverly H. Banister,

Acting Regional Administrator, Region 4.

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[FR Doc. 2010-4146 Filed 2-26-10; 8:45 am]