Completed Rulemakings | Air Quality Division

ADEQ maintains a list of completed rulemakings for two years after their effective dates.

New Source Review: Inter-Precursor Trading and Municipal Incinerators Rulemaking


ADEQ amended Arizona Administrative Code (A.A.C.) Title 18, Chapter 2, Articles 1 and 4, to address deficiencies found by the EPA in ADEQ’s new source review (NSR) rules, including inter-precursor trading (IPT) rules that are now disallowed.

The purpose of this rulemaking addressed two issues related to the NSR program:

First, ADEQ amended the definition of municipal incinerators to conform ADEQ’s rules to the 1990 Clean Air Act Amendments and EPA's correction of its rules that changed the definition of a “major emitting facility” with regard to municipal incinerators | 86 Federal Register 37,918 (July 19, 2021) >

Second, ADEQ amended A.A.C. Title 18, Chapter 2, Article 4, R18-2-404(a), to remove the sentence authorizing ozone IPT as required by Sierra Club v. EPA, 985 F.3d 1055 (D.C. Cir., 2021) | View >

These rule amendments are required by federal law and therefore, do not increase regulatory burden beyond what is required by the Clean Air Act. If ADEQ does not address this requirement, EPA is required to issue a finding of failure to submit or a disapproval for those elements of the 2015 ozone State Implementation Plan revisions. If the deficiencies remain uncorrected, EPA must impose sanctions, including 2-for-1 offsets, the loss of highway funds and a federal implementation plan.


  • Notice of Proposed Expedited Rulemaking Docket Opening | View >
  • Notice of Proposed Expedited Rulemaking | View >
  • Notice of Final Expedited Rulemaking | View >
  • Effective Date: May 4, 2022