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Adequacy Status of the Denver, Colorado PM10

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Information about this document as published in the Federal Register.

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Environmental Protection Agency (EPA).


Notice of adequacy.


In this document, EPA is notifying the public that we have found that the motor vehicle emissions budgets in the Denver particulate matter of 10 micrograms in size or smaller (PM10) maintenance plan submitted on July 30, 2001, are adequate for conformity purposes. On March 2, 1999, the D.C. Circuit Court ruled that submitted State Implementation Plans (SIPs) cannot be used for conformity determinations until EPA has affirmatively found them adequate. As a result of our finding, the Denver Regional Council of Governments, the Colorado Department of Transportation and the U.S. Department of Transportation are required to use the motor vehicle emissions budgets from this submitted maintenance plan for future conformity determinations.


This finding is effective October 29, 2001.

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Kerri Fiedler, Air & Radiation Program (8P-AR), United States Environmental Protection Agency, Region 8, 999 18th Street, Suite 300, Denver, Colorado 80202-2466, (303) 312-6493.

The letter documenting our finding is available at EPA's conformity website:​oms/​transp/​conform/​adequacy.htm.

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Throughout this document wherever “we,” “us,” or “our” are used we mean EPA.

This action is simply an announcement of a finding that we have already made. We sent a letter to the Colorado Air Pollution Control Division on September 20, 2001 stating that the motor vehicle emissions budgets in the submitted Denver PM10 maintenance plan are adequate. This finding has also been announced on our conformity Web site at​oms/​transp/​conform/​adequacy.htm.

Transportation conformity is required by section 176(c) of the Clean Air Act. Our conformity rule requires that transportation plans, programs, and projects conform to SIPs 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.

The criteria by which we determine whether a SIP's motor vehicle emission budgets are adequate for conformity purposes are outlined in 40 CFR 93.118(e)(4). Please note that an adequacy review is separate from our completeness review, and it also should not be used to prejudge our ultimate approval of the SIP. Even if we find a budget adequate, the SIP could later be disapproved, and vice versa.

We've described our process for determining the adequacy of submitted SIP budgets in a memo entitled, “Conformity Guidance on Implementation of March 2, 1999 Conformity Court Decision,” dated May 14, 1999. We followed this guidance in making our adequacy determination.

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

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Dated: October 4, 2001.

Andrew M. Gaydosh,

Acting Regional Administrator, Region VIII.

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[FR Doc. 01-25739 Filed 10-11-01; 8:45 am]