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Final PM2.5 Project-Level Conformity Analysis for the Ohio River Bridges Project in Louisville, Kentucky

I. Executive Summary

The Louisville Metro Area ( LMA) of Louisville, Kentucky and Southern Indiana has been designated as nonattainment of the national ambient air quality standards (NAAQS or "standards") for fine particulate matter (PM2.5). Based on the Transportation Conformity regulations found in 40 CFR 93.123(b)(1) (as amended March 10, 2006) all transportation projects in the Louisville, Kentucky/Southern Indiana area are required to address project level or "hot-spot" considerations 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 the Ohio Rivers Bridges (ORB) project.

The analysis was based on two types of comparisons. First, a build verses no-action comparison was made. Second, a surrogate analysis was used. A "surrogate" (or substitute) site is a site for which the current levels of Annual Average Daily Traffic (AADT) and truck traffic are comparable to or greater than those of the future worst-case build scenario. If, additionally, the surrogate site has a monitor in the vicinity with current PM2.5 design values less than the standards, then one can logically conclude that the worst-case build scenario will not cause or add to an existing PM2.5 violation.

In summary, based on the analysis discussed below, it is determined that the ORB project meets all the project-level conformity requirements, and that the proposed ORB project will not cause or contribute to a new violation of the PM2.5 NAAQS, or increase the frequency or severity of a violation.

II. Purpose of this document

The Ohio River Bridges (ORB) project is within the Louisville KY-IN PM2.5 nonattainment area; and, therefore, the project is required to meet Transportation Conformity requirements found in 40 CFR 93.123(b)(1) (as amended March 10, 2006). This document addresses the project-level transportation conformity requirements for the ORB project, including a project level or "hot-spot" analysis that is described in greater detail in Section V.

The Clean Air Act section 176(c) requires that federally supported highway and transit project activities are consistent with state air quality goals, found in the state implementation plan (SIP). The process is called Transportation Conformity. Conformity to the SIP means that transportation activities will not cause new violations of the national ambient air quality standards (NAAQS or "standards"), worsen existing violations of the standard, or delay timely attainment of the relevant standard.

Transportation conformity is required for federal supported transportation projects in areas that have been designated by the U.S. Environmental Protection Agency (EPA) as not meeting a NAAQS. These areas are called nonattainment areas if they currently do not meet air quality standards or maintenance areas if they have previously violated air quality standards, but currently meet them and have an approved maintenance plan as defined in Clean Air Act, Section 175A, Maintenance Plan. On January 5, 2005, the EPA designated the Louisville KY-IN area (Jefferson and Bullitt counties, Kentucky and Clark, Floyd and Jefferson (partial) counties, Indiana) as nonattainment for fine particulate matter, called PM2.5. This designation became effective on April 5, 2005, 90 days after EPA's published action in the Federal Register. Transportation conformity for the PM2.5 standards applied on April 5, 2006, after the one-year grace period provided by the Clean Air Act. After that time, metropolitan PM2.5 nonattainment areas must have in place a transportation plan and transportation improvement program (TIP) that conform and federally supported projects must also be shown to conform after the end of that grace period. 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.

The ORB PM2.5 hot-spot analysis could not be completed until the amendment was final. Since a Final Environmental Impact Statement (FEIS) was issued in April 2003 and a Record of Decision (ROD) issued in September 2003 for the ORB project, the PM2.5 hot-spot analysis was not included in the FEIS. Therefore, public review and comment for this hot-spot analysis is being undertaken separately from that of the ORB FEIS.

The National Environmental Policy Act process has been completed and the Federal Highway Administration (FHWA) approved the ROD in September 2003. The ORB project is in the design phase.

Updated: 7/6/2011
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