How is transportation conformity determined in noncontiguous PM2.5 nonattainment areas?
Noncontiguous PM2.5 nonattainment areas are areas that contain “satellite portions” that are not contiguous with the main portion of the nonattainment area. These satellite areas are designated as part of the overall nonattainment area because they have a point source which contributes, via transport, to the air quality problems of the main geographic portion of the PM2.5 nonattainment area. The satellite portions of noncontiguous PM2.5 nonattainment areas should be treated as donut areas for transportation conformity purposes. Section 93.101 of the conformity rule defines “donut areas” as “geographic areas outside a metropolitan planning area boundary, but inside the boundary of a nonattainment or maintenance area that contains any part of a metropolitan area(s). These areas are not isolated rural nonattainment and maintenance areas.” Transportation conformity guidance for donut areas is provided in EPA’s “Companion Guidance for the July 1, 2004, Final Transportation Conformity Rule:
Related Questions
- Nonattainment areas also have to comply with transportation conformity requirements, which set limits for emissions from on-road vehicles. Will the EAC limit motor vehicle emissions?
- How many metropolitan areas have experienced a transportation conformity lapse?
- When will conformity apply in PM2.5 nonattainment areas?
