EPA Policy Change in Maximum Achievable Control Technology Standards

Last week, the EPA reversed a 20 year-old policy that mandated facilities once subject to Maximum Achievable Control Technology (MACT) standards applicable to “major sources” of federally listed hazardous air pollutants (HAPs) would always remain subject to MACT standards even if their HAP emissions would no longer qualify them as “major sources.” Now the EPA is allowing sources once determined a “major source” to be recognized as “minor sources” for HAPs and allow those sources to no longer be held to MACT standards. This reverses the longstanding “once in, always in” MACT policy.

To provide background, Section 112 of the Clean Air Act (part of the 1990 amendments) mandated that the EPA promulgate MACT standards on an industry-by-industry basis applicable to “major sources” of federally listed HAPs. The definition of a “major source” is a facility that has the potential to emit (PTE) more than 10 tons per year of any individual HAP or 25 tons per year of aggregated HAPs. In 1995, the EPA adopted guidance that unless a source limited (by permit) its PTE to less than the major source thresholds by the effective date of the applicable MACT, the source was and would always remain subject to MACT. In other words, a source could not go back and measure limits on HAP emissions below major source thresholds and remove itself from MACT applicability. Also, the EPA’s historic enforcement position has been that the source that took (timely) limits on its PTE, but then violated those limits, would be required to comply with MACT even if it returned to compliance within the limits. Finally, major sources of HAPs and those subject to the MACT need a Title V operating permit, which carries additional regulatory burdens.

If you have questions regarding how this recent EPA decision may benefit your facility, or any other environmental issues, please contact a member of the Warner Norcross + Judd Resources, Energy and Environment Group. We provide counsel and representation in Michigan and across the nation.