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Clarification to the Transportation Conformity Guidance for Qualitative Hot-spot Analysis in PM2.5 and PM10 Nonattainment and Maintenance Areas

On March 29, 2006, the Environmental Protection Agency (EPA) and the Federal Highway Administration (FHWA) issued joint guidance on how to perform qualitative hot-spot analyses in PM2.5 and PM10 nonattainment and maintenance areas titled, "Transportation Conformity Guidance for Qualitative Hot-spot Analysis in PM2.5 and PM10 Nonattainment and Maintenance Areas" (March 2006 guidance). The guidance provides information for State and local agencies to meet the PM2.5 and PM10 hot-spot analysis requirements established in the March 10, 2006, final transportation conformity rule (71 FR 12468).

Since issuing the March 2006 guidance, a lawsuit was filed challenging a project's conformity determination, including the project's PM2.5 hot-spot analysis that relied on method A (comparison to another location with similar characteristics). Method A is described in question 4.1 of the March 2006 guidance. As part of a settlement agreement on that lawsuit (Environmental Defense, et al. v. USDOT, et al., No. 08-1107 (4th Cir., dismissed Nov. 17. 2008)), FHWA agreed to issue a clarification on a specific schedule, in coordination with EPA, to the March 2006 guidance. This clarification does not supersede the March 2006 guidance or the March 10, 2006 final transportation conformity rule; it only further explains how to implement the existing guidance and the hot-spot analysis requirements in the final rule. The clarification also does not create any new requirements and does not serve as guidance for PM2.5 and PM10 quantitative hot-spot analyses.

HTML and PDF Versions of the final clarification can be found here - (HTML) and (PDF - 22Kb)

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Comments on the draft clarification should be sent to no later than March 16, 2009.

Updated: 10/20/2015
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