Pre-preconstruction permits: Can building begin without one?
Just like blueprints, hard hats, and scaffolding, permits are synonymous with construction. Most businesses have to get permits before breaking ground on a project. However, recent federal guidance on preconstruction permits for air emissions indicates that some construction activities may be able to start without a permit.
The Environmental Protection Agency (EPA) requires businesses to obtain a preconstruction permit for a new facility or major modifications to an existing facility before starting construction. It ensures that new or modified facilities will be able to comply with air emissions requirements. In September 2025, the agency published guidance (in the form of a response letter), determining that a company may start construction activities on parts of a new facility unrelated to air emissions before obtaining a permit.
Let’s take a look at the preconstruction permit regulations, the facts of the case in the guidance, and EPA’s plans to clarify which construction activities can begin before obtaining a preconstruction permit.
What are the preconstruction permit requirements?
Under the New Source Review (NSR) regulations (40 CFR Part 51 Subpart I and Part 52 Subpart A), businesses that build a new facility or make major modifications to an existing one have to obtain a preconstruction permit to “begin actual construction.” EPA defines “begin actual construction” as “physical on-site construction activities on an emissions unit which are of a permanent nature.” It covers activities including (but not limited to) installing building supports and foundations, laying underground pipework, and constructing permanent storage structures.
There are three types of preconstruction permits: Prevention of Significant Deterioration (PSD) permits, nonattainment NSR permits, and minor source permits. The permits define:
- What construction is allowed,
- Emissions limits, and
- How the source must be operated (if applicable).
It’s important to note that most preconstruction permits are issued at the state or local levels. The requirements must be at least as stringent as EPA’s.
What’s the case?
A county air quality district in Arizona asked EPA to assess whether it may allow a company to start the first phase of construction on a semiconductor manufacturing facility before obtaining an NSR permit if no emissions units are involved.
EPA answered the request with TSMC Arizona Begin Actual Construction — EPA Response Letter (September 2, 2025) and published the letter as new guidance.
Facts of the case
The company builds its facilities in three phases and doesn’t install the semiconductor manufacturing equipment until all phases are complete.
The first phase of construction consists of building the core and shell of the facility, which includes the foundation, a steel superstructure, and external walls. The building will eventually house emissions units (semiconductor manufacturing equipment). However, the company stated that the first phase of construction doesn’t involve any air pollution control devices, emissions units, or foundations for emissions units.
The county air quality district agreed that if a structure contains no emissions unit, it’s not subject to NSR permitting because it doesn’t emit or have the potential to emit pollutants.
EPA response to the case
In the September 2025 response letter, EPA recognized that the definition of “begin actual construction” prohibits on-site construction of an emissions unit without a permit, but it doesn’t prohibit on-site construction of the parts of a facility that don’t qualify as an emissions unit.
The agency determined that the county air quality district may allow the company to start the first phase of construction (even if it’s of a permanent nature) before it obtains an NSR permit as long as it doesn’t involve construction on an emissions unit.
What are EPA’s regulatory plans?
The agency will conduct rulemaking to clarify what construction activities need an NSR permit and what construction activities can proceed without one. It plans to amend the NSR regulations in 2026 by:
- Revising the definition of “begin actual construction," and
- Establishing how permitting authorities may distinguish parts of a facility that are and aren’t emissions units or parts of emissions units.
Until then, EPA will address preconstruction permitting issues on a case-by-case basis.
How should facilities respond?
If you’re planning to build a new facility or make a major modification to one, consider these tips to help you comply with the NSR regulations:
- Check whether the state and local requirements are the same as or stricter than federal rules. The state environmental department’s website is a good place to start.
- Contact the permit-issuing agency (likely the state or local air pollution control agency) for direct help with your specific project.
- Watch EPA news announcements for updates on rulemaking. You can also track the Federal Register, where the agency publishes proposed and final rules.
Key to remember: EPA plans to conduct rulemaking to help distinguish which construction activities need a preconstruction permit for air emissions and which activities don’t.