Regulatory clarification would let companies begin construction on non-emitting site infrastructure before their air permits are issued.
If you have ever experienced a delay of months — sometimes years — for an air permit, you already understand the problem EPA is trying to solve with its latest proposed rule on New Source Review (NSR) permitting.
On May 13, 2026, EPA published a proposed rule that would revise the definition of “begin actual construction” in the NSR preconstruction permitting program. In plain terms: the proposal would let project developers start building non-emitting site infrastructure before their NSR permit is issued, rather than having to freeze all construction activity until the permit arrives.
Here’s why this rule matters and what it does.
45 Years of Regulatory Ambiguity
The NSR program has required permits before beginning construction of major pollution-emitting facilities since 1977.
Under the current rules that have been essentially unchanged since 1980, “begin actual construction” includes any “physical on-site construction activities on an emissions unit which are of a permanent nature.” EPA has further interpreted this to cover structures that “accommodate” an emissions unit — meaning foundations, buildings, utility connections and concrete pads could all be off-limits until the air permit is issued.
The ambiguity has made developers delay site preparation until permit issuance — adding months of cost and schedule risk.
The result has been inconsistent interpretations across state and federal permitting authorities, project delays on everything from manufacturing plants to data centers to energy facilities, as well as additional costs with no corresponding air quality benefit.
What the Proposed Rule Would Do
EPA’s proposal cuts through the ambiguity with a simple reorientation: the permit requirement is triggered when construction begins on equipment or components that emit air pollutants — not before.
The proposed rule introduces a new defined term, “pollutant-emitting activities,” and explicitly excludes a range of non-emitting construction from that definition. Under the proposal, developers could comfortably proceed with the following before receiving a permit:
- Office buildings, retail stores and general-purpose storage structures
- Concrete pads, foundations, walls and roofs not specifically configured for emitting equipment
- Utility service infrastructure — electrical, water, natural gas, wastewater and telecommunications connections
- Site preparation activities including clearing, grading, excavation, pile driving and paving
- Flanged-off “tie-ins” — connection points for future equipment that are capped and not yet in service
Critically, none of this changes what the permit requires. Control technology analyses, ambient air quality demonstrations and all other substantive permit conditions remain fully intact. The only change is timing: developers would be able to advance non-emitting site work during the permitting process rather than waiting for it to conclude.
Why the Legal Foundation Is Solid
EPA’s proposal isn’t just good policy — it’s aligned to the Clean Air Act (CAA).
The CAA statute requires permits for construction of “major emitting facilities” and “major stationary sources.” The essential characteristic of both is that they emit air pollutants. The CAA does not require a permit before building something that doesn’t emit.
Following a Supreme Court decision which directed courts and agencies to apply the “best reading” of statutory text, EPA has undertaken a fresh analysis and concluded that its longstanding prohibition on pre-permit non-emitting construction was not required by the Act.
A Key Principle Worth Emphasizing: General-Purpose Foundations Are Not Part of the Emissions Unit
One of the most important points that should be emphasized is that the definition of “emissions unit” should be clarified. EPA has historically interpreted that term to include “any installations necessary to accommodate” an emissions unit — a reading that included foundations, building structures and support infrastructure under the permit requirement.
Foundations and buildings that do not provide structural support to an emissions unit are not part of that emissions unit — and never were.
A foundation that supports a general-purpose building or a concrete pad that could serve any number of uses, has no functional relationship to the emissions unit. Only foundations and structures that physically bear, anchor or integrate with pollutant-emitting equipment should be treated as “construction on” an emissions unit for permitting purposes.
The Bottom Line
This proposed rule is simultaneously the right legal result, sound policy and practically beneficial for American industry. Allowing non-emitting site preparation to proceed during the permit review process, which routinely takes 12 to 18 months or more on complex projects, can compress overall project timelines by months, reduce financing costs and get domestic manufacturing, energy and infrastructure projects to completion faster.
It does all of this without touching a single substantive emission control requirement or air quality standard. The environment is not less protected; it is protected in exactly the same way, just without restriction on non-emitting site work.
If you’re interested in submitting comments about the proposed rule to the EPA, visit regulations.gov, referencing Docket ID: EPA-HQ-OAR-2025-0618 by June 29, 2026.
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