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EPA Reverses MACT Once-In-Always-In Policy

On January 25, 2018, EPA issued a guidance memo reversing its long-held policy that a major source of HAP must stay subject to MACT standards, even if it subsequently reduces its HAP emissions to minor (area) source levels (i.e., the “once-in-always-in” policy). Now, EPA is stating that HAP major sources can reduce their emissions to minor source levels and become area sources of HAP at any time – even after the relevant compliance date of a major source MACT standard.  This could enable several facilities to avoid applicability of major source MACT standards.

EPS is evaluating this development for applicability to our clients – identifying where regulatory burden may be eased due to this change in policy.

Who May Benefit from this Action?

If your facility has made HAP emissions reductions to meet a MACT standard or possibly other voluntary reductions and your actual emissions are below the 10 ton/yr individual HAP and 25 ton/yr total HAP major source thresholds, you may be able to apply for Synthetic Minor limits, become an area source, and then no longer be subject to the MACT standard.

This could provide relief from the onerous monitoring, recordkeeping, and reporting requirements of the MACT standards.

Also, if the MACT standard is the only reason your facility has a Title V permit, then you could possibly downgrade to a Synthetic Minor permit (or possibly True Minor permit). This would also reduce reporting burden, and in many cases, annual air emissions or air permit fee costs.

If you believe that your facility may be a candidate to benefit from this action, please contact your EPS consultant.

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