On October 1, 2020, the EPA Administrator signed final revisions to 40 CFR Part 63, National Emission Standards for Hazardous Air Pollutants for Source Categories.
The rule will become effective sixty (60) days after publication in the Federal Register. The rule is designed to formalize EPA’s 2018 guidance memorandum which overturned EPA previous policy of “once in, always in” (OIAI), which is often referred to as the May 1995 Seitz Memorandum.
The rule also finalizes revisions to the Part 63 General Provisions clarifying “that a major source can be reclassified to area source status at any time upon reducing its potential to emit (PTE) hazardous air pollutants (HAP) to below the major source thresholds (MST) of 10 tons per year (tpy) of any single HAP and 25 tpy of any combination of HAP.”
Additionally, the final rule specifies compliance dates, notification, and recordkeeping provisions applicable to sources electing to reclassify to area source status or to sources reverting back to major source status. A copy of the prepublication version of the rule is available here.
