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The PPM Blog

“Once In, Always In” Is on the Way Out!

In May of 1995, EPA’s John Seitz released a memo that clarified a “Once in, Always in” policy for Maximum Achievable Control Technology (MACT) sources. These sources had a Potential to Emit (PTE) of 10 tons of any single Hazardous Air Pollutant (HAP) or 25 tons of aggregate HAPs – also known as a “major source”. This memo, in short, required any major source of HAPs subject to a MACT to always comply with the MACT standards to which the facility is subject. For many facilities, this meant that they would be required to obtain a Title V permit and adhere to the requirements of both Title V and MACT standards. This includes Annual Compliance Certifications, Annual Emission Reports, Title V Fees and quarterly or semi-annual MACT reporting among many other requirements such as performance testing.

What if your facility no longer met the PTE thresholds of a “major source”? For instance, maybe the facility was over-ambitious in production estimates at startup and never reached a HAP major source threshold. Perhaps the facility has begun to use a more environmentally friendly product significantly reducing the PTE. Things change over time and so should permitting conditions. Based on Mr. Seitz memo from May of 1995, your facility was still required to keep all the permits and the requirements of a major source.

Until now…

On January 25, 2018, EPA released a new memo rolling back the requirement of the 1995 memo.

EPA states: 

“On January 25, 2018, EPA issued a guidance memorandum withdrawing the “once in always in” policy for the classification of major sources of hazardous air pollutants under section 112 of the Clean Air Act.  With the new guidance, sources of hazardous air pollutants previously classified as “major sources” may be reclassified as “area” sources at any time, provided the facility limits its potential to emit below major source thresholds.”

Facilities which could potentially benefit from the latest regulatory roll-back should consider that this legislation is very likely to see challenges in court before it is finalized in the Federal Register. Some states are likely to continue the “Once in, Always in” policy until such time that the memo is finalized.

If you would like to know more about how this recent change can affect your facility and how it reduced the regulatory burden of an outdated Title V or MACT standard, consider contacting the Air Permitting specialists at PPM Consultants. See how we can simplify the complexity of your current regulatory status.

Contributed by Paul Hansen, P.E.
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