Approved in some parts of a state and not in others — the permitting regime that keeps clean air from degrading
The Environmental Protection Agency proposed approving the portions of Arizona plan covering three permitting jurisdictions and disapproving the portion covering one county. The subject is the permitting regime that keeps air quality from degrading where standards are already met.
Document overview (primary data)
- Document typeProposed rule
- AgencyEnvironmental Protection Agency
- Citation91 FR 50742
Key points
- The Environmental Protection Agency proposed to partially approve and partially disapprove a revision to the Arizona state implementation plan.
- The subject is the permitting regime keeping air quality from degrading in areas that meet the standard.
- The state agency and several county agencies each hold permitting authority, and federal review proceeds by those units.
- Three permitting jurisdictions are proposed for approval and one county jurisdiction for disapproval.
- The same document withdraws part of a proposed rule published in 2024 on the same requirements.
1Regulation where the standard is met
The air regime looks centered on areas failing the standard, yet areas meeting it have machinery too. If air worsens slightly each time a new facility is built, the standard eventually falls. So in areas holding clean air, new construction and major modification require a permit, bounding how far quality may slip. The program is called prevention of significant deterioration.
They are separate programs, yet both are prepared by the state as parts of its implementation plan and approved federally. This site separately covers control measures in nonattainment areas; read together, the shape of the whole regime emerges.
2Several permitting authorities within one state
| Permitting jurisdiction | What is proposed here |
|---|---|
| The state department of environmental quality | Approval |
| Maricopa County air quality department | Approval |
| Pinal County air quality control district | Approval |
| Pima County department of environmental quality | Disapproval |
Within one state, the state agency and several county agencies each hold permitting authority. Federal review proceeds by those units, so a single state submission can be approved in some places and disapproved in others. The unfamiliar shape of a partial approval and partial disapproval follows from that structure.
3What disapproval leads to
Where part of a plan is not approved, the requirements remain unmet for that part. The Clean Air Act holds machinery for that situation: the federal government may write a plan itself, and sanctions may follow. This site separately covers a finding of failure to submit and what followed from it, so what happens absent approval can be traced.
4Withdrawing an earlier proposal
The document also withdraws part of a proposed rule published in 2024. Issuing a new proposal on the same question requires tidying the old one. Where a rulemaking runs for years, proposals may be replaced partway, and that tidying too happens through open procedure.
Why it matters
Where permitting authority is split between state and county, the approval status of the applicable plan can differ by where a facility sits. New construction or modification calls for checking at the jurisdiction level.
FAQ
Are areas meeting the standard regulated too?
Why partial approval and partial disapproval?
Sources (primary)
Source: Federal Register (federal documents, public domain). Links go to the official site.