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1. Executive Summary

The Birmingham area is designated as nonattainment of the National Ambient Air Quality Standards (NAAQS or "standards") for fine particulate matter (PM2.5). All transportation projects in the Birmingham Nonattainment area that meet the requirements found in 40 CFR 93.123(b)(1) of the Transportation Conformity regulations (as amended March 10, 2006) are required to conduct a "hot-spot" analysis for PM2.5.

According to 40 CFR 93.123(b) (2) and (4), a quantitative analysis for applicable projects is not required until EPA releases modeling guidance in the Federal Register. However, a qualitative hot-spot analysis is required in order to assess whether the project will cause or contribute to any new localized PM2.5 violations, increase the frequency or severity of any existing violations, or delay timely attainment of the PM2.5 NAAQS. This document addresses those requirements for APD-471(038) "Corridor X from I-65 to US-31" and IM-I065 (303) "Additional Lanes on I-65 from 16th St to Walker's Chapel Rd."

The Interagency Group met on January 29, 2007 to discuss the project. Agencies represented included the Federal Highway Administration, Alabama Department of Transportation, Alabama Department of Environmental Management, Environmental Protection Agency, Jefferson County Department of Health and the Regional Planning Commission of Greater Birmingham. Through the interagency consultation process it was determined that this project is a project of air quality concern and a qualitative hot-spot analysis was the appropriate way to proceed for this project. The interagency consultation group determined that there was not another location with similar characteristics suitable for comparison. The interagency consultation group recommended developing the qualitative analysis based upon existing air quality studies.

Based on the qualitative analysis it is determined that the Corridor X / Interstate 65 project meets all the project-level conformity requirements, and that the proposed Corridor X / Interstate 65 project will not cause or contribute to a new violation of the PM2.5 NAAQS, or increase the frequency or severity of a violation.

2. Purpose of this Document

On April 5, 2005, the nonattainment designations for Fine Particulate Matter (PM2.5) became effective. In the Birmingham region, the area designated as nonattainment includes all of Jefferson and Shelby counties, as well as a small portion of southern Walker County. Transportation plans, programs and projects were required to meet conformity requirements for the PM2.5 standard by April 5, 2006; one year after the nonattainment designation took effect. After that time, metropolitan PM2.5 nonattainment areas were required to have in place a conforming transportation plan and transportation improvement program (TIP) and all federally supported transportation projects must also be shown to conform. For PM2.5, project-level conformity also requires an assessment of localized emissions impacts for projects that are deemed to be of air quality concern as defined in 40 CFR 93.123(b)(1) (as amended March 10, 2006). This localized assessment is called a hot-spot analysis. A hot-spot analysis assesses the air quality impacts on a scale smaller than an entire nonattainment or maintenance area, including for example, congested roadway intersections and highways or transit terminals. Such an analysis is a means of demonstrating that a transportation project meets Clean Air Act conformity requirements to support state and local air quality goals with respect to potential localized air quality impacts. When a hot-spot analysis is required, it is included within the project-level conformity determination that is made by FHWA or the Federal Transit Administration (FTA).

The Corridor X and I-65 project is within the Birmingham PM2.5 nonattainment area; and, therefore, the project is required to meet Transportation Conformity requirements found in 40 CFR 93. This document addresses the project-level transportation conformity requirements for the Corridor X and I-65 project, including a "hot-spot" analysis.

Updated: 7/6/2011
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