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New Source Review (NSR) Permitting

Draft Guidance: Interpretation of "Begin Actual Construction" Under thew New Source Review Preconstruction Permitting Regulations

This guidance addresses EPA’s interpretation of “begin actual construction” under the regulations implementing the New Source Review (NSR) permitting program. An owner or operator of a major stationary source or major modification must obtain an NSR permit before “begin[ning] actual construction” on the facility. Currently, EPA considers almost every physical on-site construction activity that is of a permanent nature to constitute the beginning of “actual construction,” even where that activity does not involve construction “on an emissions unit.” This interpretation tends to preclude source owners/operators from engaging in a wide range of preparatory activities they might otherwise desire to undertake before obtaining an NSR permit. In this draft guidance, EPA is adopting a revised interpretation that is more consistent with the regulatory text. Under this revised interpretation, a source owner or operator may, prior to obtaining an NSR permit, undertake physical on-site activities – including activities that may be costly, that may significantly alter the site, and/or are permanent in nature – provided that those activities do not constitute physical construction on an emissions unit.

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