Beveridge & Diamond
Related Practices
Related Practices

Court Remands EPA Transportation Conformity “Hot Spot” Rule

Beveridge & Diamond, P.C., December 14, 2007

On December 11, the D.C. Circuit remanded a key portion of EPA’s 2006 rule governing project-level “hot spot” conformity determinations for transportation projects.  Environmental Defense v. Johnson, No. 06-1164 (D.C. Cir., Dec. 11, 2007); see also PM2.5 and PM10 Hot Spot Analyses in Project-Level Transportation Conformity Determinations for the New PM2.5 and Existing PM10 National Ambient Air Quality Standards, 71 Fed. Reg. 12468 (Mar. 10, 2006), codified at 40 C.F.R. Part 93.

In a challenge to a 2006 final rule, the federal court held that EPA improperly failed to condition federal highway funding on a demonstration that particular projects, such as a new highway intersection, will not “delay timely attainment” of localized air quality goals for particulate matter.  In its 2006 rule, EPA required hot spot analysis to show that the project did not exacerbate existing air quality problems, but did not require a showing that the transportation project would not slow progress toward attainment of air quality standards.  The court expressed concern that localized project emissions could “counterbalance” other air quality control measures and thereby delay attainment of air quality standards; accordingly, the court sent the rule back to EPA for a more detailed justification.

In a related ruling, the court reaffirmed EPA’s current position that transportation projects do not have to affirmatively reduce regional emissions, as long as the project’s emissions do not increase overall violations of regional air quality standards (as opposed to localized “hot spot” effects).  The court also approved EPA’s decision to withdraw its MOBILE 6.2 guidance on quantitative modeling as it relates to hot spot analysis.

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