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USEPA Issues Final Rules Allowing Major Sources to Reclassify as Area (Minor) Sources

Since the beginning of the Title V program many years ago, the term “Once In Always In” meant that if a facility becomes a major source and is subject to a NESHAP found in 40 CFR Part 63, then that NESHAP would perpetually apply to that facility.

As an environmental professional, I have witnessed the significant consternation for the industry in that there was no longer an incentive to reduce air pollution as a method to reduce the regulatory burden in which the company is subjected. We have even seen a company relocate their operations to start the permitting process anew to “opt out” of major source status. Thankfully, welcome relief is finally on the way.

After further review of the Clean Air Act (CAA), the USEPA concluded that the statutory definitions of major source and area source contain no language fixing a source’s status and contain no language suggesting a cutoff date after which the source’s status cannot change. Accordingly, the USEPA determined a major source may reclassify as an area source at any time upon reducing its Hazardous Air Pollutant (HAP) emissions and potential-to-emit (PTE) below applicable major source thresholds (MSTs).

Therefore, in a rule published in the Federal Register on November 19, 2020, the USEPA finalized amendments to the General Provisions of 40 CFR Part 63 Subpart A to implement the “plain language” reading of the ‘‘major source’’ and ‘‘area source’’ statutory definitions of the CAA and provide that a major source can be reclassified to area source status at any time upon reducing its PTE to below the MST of 10 tons/year of any single HAP and 25 tons/year of aggregate HAPs.

Specifically, the USEPA has amended 40 CFR 63.1 by adding a new paragraph (c)(6). This paragraph specifies that a major source may become an area source at any time upon reducing its HAP PTE to below the MSTs established in 40 CFR 63.2. Note that major sources that reclassify to area source status may still be subject to applicable 40 CFR Part 63 area source NESHAP requirements.

Notification requirements found in 40 CFR Part 63.9 have also been amended to cover cases where a source switches from major to area source status. These notifications may be required to be submitted electronically through the Compliance and Emissions Data Reporting Interface (CEDRI).

This is good news for major sources that are now able to pursue pollution prevention techniques to reduce emissions at the source. This will not only help the industry reduce permitting and emission fees but also save on raw material costs as the most effective pollution prevention techniques address source reduction.

Each state still needs to get on board and amend its own rules, which should be in the works in many states. Keep following our blog for updates as they occur.

CFR Environmental has a long track record of providing support related to air permitting, compliance, and reporting projects. Our expertise includes Renewable Operating Permits (ROP), Permits to Install (PTI) and Potential to Emit (PTE) projects for compliance with state and federal regulations. Contact us to learn more about our air consulting services.


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