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News Releases from HeadquartersAir and Radiation (OAR)

EPA Continues to Improve and Clarify Clean Air Permitting Process

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WASHINGTON (October 22, 2020) — Today, the U.S. Environmental Protection Agency (EPA) finalized a rule to further streamline and improve the Clean Air New Source Review (NSR) permitting process. Specifically, today’s action will clarify the process for evaluating whether a NSR preconstruction permit is needed when an existing major-emitting facility plans to make changes to its facility.
“Today’s rule is part of the Trump Administration’s goal to revitalize and modernize our nation’s industrial operators while maintaining clean air progress,” said EPA Administrator Andrew Wheeler. “This rule incentivizes installation of new technologies that can both improve operator efficiency and reduce air pollution.”
In March 2018, the EPA Administrator issued a memorandum titled “Project Emissions Accounting Under the New Source Review Preconstruction Permitting Program.” In the memorandum, the Administrator explained that the agency interprets current NSR regulations to allow emissions decreases as well as increases from a project to be considered at Step 1 of the NSR applicability process. This rule provides further clarity and certainty to the regulated community regarding the permissibility of project emissions accounting.
EPA expects that allowing project emissions accounting will reduce regulatory burden -- saving time and money without sacrificing environmental protection. Where a review of both the emissions increases and the emissions decreases associated with a proposed project indicates that the project will not result in a significant emissions increase, this review would end the applicability evaluation. In general, the project could then proceed under a minor source permit as applicable. Those state and local air agencies that implement the NSR program through EPA-approved State Implementation Plans (SIPs) need not allow for project emissions accounting nor are they required to submit SIP revisions or stringency determinations to EPA as a result of this action.
Under this Administration, EPA has taken numerous steps to clarify and improve New Source Review (NSR) permitting requirements including guidance to:
Communicate how EPA would apply and enforce the Actual-to-Projected Actual Emissions Applicability Test;
Clarify the meaning of “Common Control” and “Adjacent” in the context of determining the scope of a stationary source;
Identify additional circumstances under which an area may be excluded from  “Ambient Air”;
Provide PM2.5 and Ozone Significant Impact Level (SIL) guidance; and
Provide guidance on plantwide applicability limits or PALs. 
EPA has also issued final actions to complete the reconsideration of prior agency actions on project aggregation and reasonable possibility in the context of Clean Air Act permitting and to streamline tribal oil and gas permitting activities.  All of these actions will improve regulatory certainty and remove unnecessary obstacles to projects aiming to improve the reliability, efficiency, and safety of facilities while maintaining air quality standards.
The New Source Review preconstruction permitting program was established in the 1977 Clean Air Act Amendments. The program is intended to ensure environmental protection while allowing for economic growth  by requiring  the installation of state of the art technology when new plants are built or existing plants undergo major modifications since that is the most cost effective time to make such emission controlling improvements.
Under the NSR program, before constructing a new stationary emission source or a modification of an existing major source, the source owner or operator must determine whether the new source will emit or the modification will increase air emissions above certain thresholds. If so, the source owner or operator must obtain a permit from a state permitting agency (or EPA in limited areas)  that may require installation of pollution control technology or other emission controlling measures.