The United States Environmental Protection Agency (EPA) published the ﬁnalized amendments to the General Provisions that apply to the National Emission Standards for Hazardous Air Pollutants (NESHAPs) under section 112 of the Clean Air Act (CAA) in the Federal Registrar on October 1, 2020.
These amendments allow a source to reclassify to an “area source” (non-major) of Hazardous Air Pollutants (HAP)s at any time upon reducing its Potential to Emit (PTE) below 10 tons per year (tpy) of a single HAP or 25 tpy of all HAPs combined.
Amendments to NESHAPs under the Clean Air Act include:
- Implement the plain language reading of the “major source” and “area source” definitions of section 112 of the CAA.
- Allow a major source of HAPS only to be reclassiﬁed to area source status at any time upon reducing its PTE HAPs below the major source thresholds (MST) of 10 tpy of any single HAP and 25 tpy of any combination of HAPs.
- Finalizes amendments to clarify compliance dates, notification, and record-keeping requirements that apply to sources choosing to reclassify to area source status and to sources that revert back to major source status, including a requirement for electronic notification.
The final rule is eﬀective as of January 19, 2021
The action implements the 2019 US EPA guidance memorandum withdrawing the “Once In, Always In” (OIAI) policy, which the agency had been following since 1995.
In 1995 the US EPA issued the “Potential to Emit for MACT Standards – Guidance on Timing Issues” memorandum, commonly referred to as the “once in, always in” (OIAI) policy. The OIAI policy stated that facilities may switch to area source status at any time until the ‘first compliance date’ of the standard,” with “first compliance date” being defined to mean the “first date a source must comply with an emission limitation or other substantive regulatory requirement.” Thereafter, under the OIAI policy, “facilities that are major sources for HAP on the ‘first compliance date ‘ are required to comply permanently with the MACT standard.”
For a link to EPA’s website regarding this modification, including the final rule, visit:
The new rule provides sources that have reduced HAP emissions to below major source thresholds the flexibility to reclassify to area source status in a more expeditious manner. By allowing a source to reclassify at any time, EPA expects facilities to have an incentive to reduce HAP emissions below MST without having to wait for specific compliance deadlines such as a permit renewal (typically every five years) or a revision to their permit. Sources who reclassify their HAP status may not need to obtain an operating permit under Title V of the CAA (this is dependent upon the source’s status with regards to other criteria pollutants).
If you have questions regarding this reclassiﬁcation process or other Clean Air Act related topics such as air permits, emissions calculations, or reporting, the environmental compliance team at NGE can assist you.