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Transportation Conformity Highlights

March 2008

Prepared by the Office of Natural and Human Environment Federal Highway Administration

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EPA Issued Revised Ozone Standards. US EPA issued a revised primary and secondary National Ambient Air Quality Standard (NAAQS) for ozone on March 12, 2008. The revised more-stringent primary standard for ozone was set at 0.075 parts per million (ppm) measured over an 8-hour period. EPA has revised the secondary standard, designed to protect welfare, at 0.075 ppm making it identical to the primary standard. The existing ozone standard was set in 1997 at 0.08 ppm. EPA analysis shows 85 counties in nonattainment under the existing 0.08 ozone standard. With a 0.075 standard, EPA estimates that 28 counties would remain in nonattainment by 2020. If the 0.075 standard were in effect today, 345 counties would not attain the standard. EPA is expected to finalize the nonattainment designations by March 2010 based on these revised standards. According to this schedule, conformity will apply in 2011, one year after the final nonattainment designations become effective. More details on the revised standards are available at:

EPA Released New Emissions Standards for Locomotives and Marine Diesel Engines. The new standards are expected to reduce pollution from locomotive and marine diesel engines by up to 90 percent. Known as EPA's Clean Diesel Locomotive and Marine program, the rule cuts emissions from all types of diesel locomotives, including line-haul, switch, and passenger rail, as well as from a wide range of marine sources, including ferries, tugboats, Great Lake freighters and all types of marine auxiliary engines. For the first time ever, this rule requires remanufacturing standards for marine engines, reductions in engine idling, and the use of after treatment technology that will further reduce diesel emissions. Phasing in tighter long-term standards for PM and NOx will begin in 2014 for marine diesel engines and in 2015 for locomotive engines. Advanced after-treatment technology will apply to both types of engines. The effective dates for NOx will be two years earlier from last year's proposal, bringing cleaner air sooner. For more information is available at: for Clean Diesel Locomotive and for Clean Diesel Marine.

Early Action Compact Areas Designated in Attainment of 8-hour Ozone Standard. On January 31, EPA announced that it would designate 13 EAC areas as attainment the 1987 8-hour ozone standard under EAC agreements. Each of 13 EAC areas demonstrated that they attained the standard by December 31, 2007. The EAC program gave certain areas the flexibility to develop early implementation strategies to attain the 8-hour ozone standard. For more information, see:

North Texans Get Cash for Dirty Trucks. More than $100 million in Texas Emission Reduction Program (TERP) funds are available to individuals, businesses, nonprofits, school districts and public agencies that own and operate heavy-duty vehicles or equipment. The funding provides rebates for the purchase and installation of new or upgraded equipment. The goal in the Dallas-Ft. Worth region is to upgrade or replace 4,500 diesel engines. SIP credits were being taken initially in the Dallas-Ft. Worth 5% Increment of Program SIP and will be taken in the 8-hour ozone attainment demonstration SIP. Funds are available in six nonattainment areas in Texas. For additional information on the TERP program, call 1-900-919-TERP or see:


EPA Releases Final Conformity Rule.On January 24 the final transportation conformity rule which implements the Clean Air Act amendments adopted in 2005 under the Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU) was published in the Federal Register. The SAFETEA-LU changes have been implemented through a joint EPA-DOT interim guidance issued on February 14, 2006. This final rule replaces the interim guidance except for the portions that address the conformity SIP or the TCM substitution and addition. Until EPA issues revised guidance on these topics, the interim guidance is still relevant. For further information and a copy of the rule, see: The rule is effective on February 25, 2008.

Training Opportunities

Introductory MOVES Training at International Emissions Inventory Conference.June 2, Portland, OR. EPA will be offering a course called "Introduction to EPA's Motor Vehicle Emission Simulator" at the 17th Annual International Emission Inventory Conference in Portland, Oregon on June 2, 2008. This is a brief (about 4 hours) hands-on introduction to the basics of MOVES including how to create a Run Specification, how to run the model and how to work with model output. It will be based on the existing highway vehicle demonstration version of MOVES posted on EPA's MOVES web page ( Details on the International Emission Inventory Conference, including information on how to register for the conference and how to sign up for courses can be found at the conference web site: The conference program ( includes a more complete description of the MOVES course, as well as a description of a basic course in the use of EPA's NMIM modeling system. Additional MOVES training classes are in the planning stages for late 2008 and early 2009.

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 is available at: For further information, contact: Mike Roberts at 404-562-3928 or at

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Updated: 10/20/2015
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