This final rule, published March 10, 2006, establishes requirements for project-level conformity determinations in particulate matter (PM) 2.5 nonattainment and maintenance areas, and revises existing requirements for projects in PM10 areas. The rule requires that PM2.5 hot-spot analyses be included in project-level conformity determinations only for new transportation projects with significant diesel traffic, such as major highway projects and projects at congested intersections that handle significant diesel traffic. For example, hot-spots could occur at congested roadway intersections and truck stops. No hot-spot analyses will be required for most projects in PM2.5 areas, because most projects do not present an air quality concern. The final rule also streamlines existing PM10 project-level requirements in a similar way. This final rule is part of EPA's implementation of the current PM2.5 standards.

General information on particulate matter or PM air pollution.

Contact:  Meg Patulski at 734-214-4842 or email:  patulski.meg@epa.gov.

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• Transportation Conformity Rule That Addresses Requirements for Project-level Conformity Determinations in PM2.5 and PM10 Nonattainment and Maintenance Areas (PDF)(45 pp, 430 K, March 10, 2006) . On March 10, 2006, EPA published a final rule requiring PM2.5 hot-spot analyses be included in project-level conformity determinations only for new transportation projects with significant diesel traffic.
• Fact Sheet: Transportation Conformity Notice of Final Rulemaking: PM2.5 and PM10 Hot-spot Analyses in Project-level Transportation Conformity Determinations for the PM2.5 and PM10 National Ambient Air Quality Standards (PDF)(EPA-420-F-06-022, 3 pp, 288K, February 2006) This document provides general information about the final rule.
• Guidance: Transportation Conformity Guidance for Qualitative Hot-spot Analyses in PM2.5 and PM10 Nonattainment and Maintenance Areas (PDF)(EPA-420-B-06-902, 35 pp, 306K, March 2006) 
• Federal Register Notice: Supplemental Notice of Proposed Rule Options for PM2.5 and PM10 Hot-Spot Analyses in the Transportation Conformity Rule Amendments for the New PM2.5 and Existing PM10 National Ambient Air Quality Standards (PDF)(17 pp, 135K, December 13, 2004)