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Transportation Conformity Highlights

January 2006

SAFETEA-LU Interim Transportation Conformity Guidance Issued. On February 14, 2006 the FHWA, FTA and EPA issued Interim Guidance on the implementation of the SAFETEA-LU Transportation Conformity provisions. This guidance discusses the SAFETEA-LU changes to the conformity requirements and how nonattainment and maintenance areas should transition to the new requirements. The guidance is available at:

SAFETEA-LU Guidance Website. The FHWA, to ensure widespread distribution of implementation guidance on the Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU) (Pub. L. 109-59, 119 Stat. 1144), is announcing the availability of a Web site that contains SAFETEA-LU implementation guidance issued by the FHWA. The implementation guidance is available at: This Web site will serve as a consolidated location to obtain all SAFETEA-LU implementation guidance issued by the agency. See the following website for the Federal Register Notice.

EPA Proposes Revisions to PM NAAQS. On December 21, 2005 EPA announced a proposal to revise the NAAQS for fine particle pollution and from some coarse particles. The Federal Register posted this proposal on January 17, 2006. The proposed revisions will address two categories of particulate matter: fine particles which are particles 2.5 micrometers in diameter and smaller; and "inhalable coarse" particles, which are particles between 2.5 and 10 micrometers (PM10-2.5). The proposed revisions include significant strengthening of EPA's standards to protect the public from short-term exposure to high levels of fine particles. For fine particles, EPA is taking comment on a range of annual and 24-hour standards, including strengthening these standards as well as retaining the standards at their present levels. EPA will take comments on the proposed revisions until April 17, 2006. The Federal Register notice may be found at:

EPA Announces Public Hearings on Proposals to Revise Particulate Matter Standard and to Revisions to Ambient Air Monitoring Regulations. EPA announced three public hearings to be held jointly for the proposed rules - "National Ambient Air Quality Standards for Particulate Matter" and "Revisions to Ambient Air Monitoring Regulations". These proposals were published in the Federal Register on January 17, 2006 (71 FR 2620 and 71 FR 2710). The hearings will be held concurrently in Chicago, Illinois; Philadelphia, Pennsylvania; and San Francisco, California on March 8, 2006 from 9 AM to 9 PM (local time). Please see:

EPA Advance Notice of Proposed Rulemaking on Transition to New or Revised Particulate Matter (PM) National Ambient Air Quality Standards. On February 9, 2006 the EPA issued an Advance Notice of Proposed Rulemaking (ANPRM) in the Federal Register. The EPA is posing a number of questions related to the transition from the current to potentially revised PM2.5 standards, as well as the transition from the current PM10 standards to potentially new PM10-2.5 standards. Comments are due to EPA on or before April 10, 2006. EPA will take final action on this proposal by September 27, 2006. See:

TRB 85th Annual Meeting. The Transportation and Air Quality Committee (ADC20) sponsored and co-sponsored several sessions at the recent TRB meeting. On Sunday, January 22 the Committee sponsored an all-day workshop entitled: A Multi-Modal Air Quality Workshop Focused on the Goods Movement Sector (Session 136). Other sessions sponsored by the Committee included: Prospects for Reducing Heavy Duty Emissions and Fossil Fuel Use (Session 363), Implementing Strategies to Control PM 2.5 and Ozone (Session 705), and Air Quality Analytical Approaches for Transportation Projects (Session 729). For more information, see

EPA Announces Potential Problems Running NMIM2005 and NONROAD2005. EPA released NONROAD2005 and NMIM2005 on December 7, 2005. On December 19, December 20, December 21, 2005 and January 6, January 31, and February 9, 2006, EPA issued a number of corrections to running these models. The NMIM2005 installation instructions were updated on December 19 and 20, NONROAD2005 Reporting Utility Problems and Corrections were announced on December 21, on January 6 several problems with NMIM2005 instructions were identified, and on January 31 and February 9, additional minor corrections to NONROAD2005 and NMIM2005 were announced. All updates are available for download from the NONROAD model web site at: For more information, contact "Dave Brzezinski" at To join in the list serve see:


PM2.5 Conformity Determinations due April 5, 2006. The PM2.5 conformity determinations are due to be completed by April 5, 2006. In PM2.5 nonattainment areas, conformity determinations on metropolitan transportation plans and TIPs must be made by FHTA/FTA by April 5, 2006. In addition, on or after April 5, 2006, project-level conformity determinations must be made prior to final NEPA approval and/or project authorizations for non-exempt projects or project phases. This applies to project authorizations made on or after April 5, 2006, even if the final NEPA approval was before April 5, 2006. State DOTs, MPOs, and project sponsors may wish to closely examine project schedules in PM2.5 nonattainment areas. Project schedules may warrant adjustment to either advance the scheduled approval or authorization to before April 5, 2006, or to allow additional time for project-level analysis.

End of Grace Period is Approaching for Required use of MOBILE6.2 and AP-42 for PM10 conformity analysis. EPA's 2-year grace period, which ends on May 19, 2006, requires that, in most cases, MOBILE6.2 and AP-42 be used in new PM10 conformity analyses. For more information, see EPA's guidance on use of MOBILE6.2 and AP-42 at:

FHWA Resource Center Training Activities.FHWA's Resource Center Air Quality Technical Services Team is available to offer air quality-related training opportunities and information can be found at:

MOBILE 6.2 Workshops Scheduled. MOBILE6.2 workshops are scheduled for February 14-15 in Hartford, CT, and February 22-23 in Ft. Lauderdale, FL. For more information, contact

If you have any suggestions for future monthly conformity highlights, please email:

FHWA Resource Center Air Quality Team Contacts:

Updated: 1/31/2017
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