On July 1, 2025, the comment period begins for the proposal to remove the emergency affirmative defense provisions in Arizona Administrative Code R18-2-306(E) from both the state operating permit program and the State Implementation Plan (SIP). The comment period ends July 31, 2025.

ADEQ proposes to remove the emergency affirmative defense provisions in Arizona Administrative Code R18-2-306(E) from both the state operating permit program (pursuant to 40 CFR Part 70) and the State Implementation Plan (SIP) as required by the Environmental Protection Agency’s (EPA’s) rule (88 Fed. Reg. 47029 (July 21, 2023)). ADEQ is proposing to retain this affirmative defense as state enforceable only.

Review Documents:

• Original Published Public Notice | View >
• State Operating Permit Program and SIP Revision | View >
• Or in person at the ADEQ Record Center | Learn How >

Public Comment Period:

Dates: July 1, 2025 – July 31, 2025

Comments may be submitted as follows:

• By Email | Send Email >     
• By Mail (Must be postmarked or received by July 31, 2025):

ADEQ
Air Quality Division
Attn: Zachary Dorn
1110 W. Washington St.
Phoenix, AZ  85007

• At Virtual Public Hearing | July 31, 2025 | 1 p.m. | View Details >