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'Project Aggregation:' PSD Applicability in the Fourth Dimension

By Eric Groten

V&E partner Eric Groten examines ‘project aggregation’ as a part of the prevention of significant deterioration preconstruction permitting review process. Read the snippet below.

The U.S. Clean Air Act imposes prevention of significant deterioration (PSD) preconstruction permitting requirements on major sources and major modifications. PSD permitting requires intensive agency review of the applicant’s proposed emission control technologies and effects on air quality, often taking a year or more.

PSD applicability generally depends on the magnitude of a project’s proposed emissions, with lower thresholds applicable to major modifications of an existing major source than to a wholly new major source. Whether a proposed new activity that emits air contaminants must be analyzed as a “major source” or “major modification” depends on its relationship to preexisting activities. If there are no other activities (1) controlled by the same person, (2) within the same basic industrial category, or (3) on contiguous or adjacent property, then the proposed new activity—the “project”—may be analyzed as a possible major new source, with a “major” emissions threshold of 100 or 250 tons per year.

This article appears in the August 2019 issue of EM Magazine, a copyrighted publication of the Air & Waste Management Association (A&WMA;

This information is provided by Vinson & Elkins LLP for educational and informational purposes only and is not intended, nor should it be construed, as legal advice.