Harmonize CAA Section 112 regulations with Section 111 regulations

Research notes

• Negative search (2026-08-27): no EPA rule, proposal or guidance in the window addresses the overlap between §112 and §111 requirements for the same sector.
• Two sectors where the overlap bites moved in this window in opposite directions — the utility hazardous air pollutant standards were repealed on 2026-02-24 while the §111 power plant repeal stays proposed — which is the mismatch the Quote asks to be tidied up, not a tidying of it.
• Gasoline terminals (found 2026-09-28, read in review). EPA’s proposed reconsideration of the gasoline distribution NESHAP (subparts R and BBBBBB) and the bulk gasoline terminal NSPS (subpart XXa), FR 2026-19774 (2026-09-28), reopens a §112 rule and a §111 rule for one source category in one action. The preamble, read in full through the Federal Register API, does not give aligning them as a reason for anything. The one change made to both families at once, evaluating vapor-recovery concentration limits on a 6-hour rolling average, is made “to provide consistency between the concentration emission limits and the test data used to establish the performance standards”. That is consistency inside each standard, not between §112 and §111. The only “harmonize” in the document is industry petitioners asking EPA to “clarify and harmonize equipment leak provisions with other equipment leak NSPS rules”, which is NSPS with NSPS. The rest is compliance relief within each rule: operating-limit calculations, duplicative recordkeeping, cargo tank vapor tightness, and the NSPS modification criteria. Not started holds; one sector, proposed, and not aimed at this Quote’s object.