- December 18 | ADEQ Comments on EPA's Proposed Determination of Attainment but for International Emissions Regarding Phoenix-Mesa Ozone | View Letter >
- June 2 | ADEQ Comments on the March 24, 2025, WOTUS Notice: The Final Response to SCOTUS | View Letter >
- May 21 | ADEQ Comments on continued funding for the Colorado River Basin Salinity Control Program | View Letters >
- April 4 | ADEQ Comments on the draft National Recommended Ambient Water Quality Criteria for the Protection of Human Health for PFAS | View Letters >
- February 24 | ADEQ Comments on the EPA's draft revisions to the Water Quality Standards Handbook | View Letters >
- February 11 | ADEQ & the Arizona AgBMP Committee Request a Comment Period Extension for the EPA's Proposed Air Plan Revisions; Arizona | View Letters >
- January 3 | ADEQ Comments on the EPA's Proposed Deadline Extension for the Regional Haze Third Planning Period | View Letter >
Nov. 27, 2024 | ADEQ Comments on EPA's Proposed Consent Decree Affecting the Hayden SO2 Nonattainment Area | View Letter >
Sept. 23, 2024 | ADEQ Comments on EPA's Proposed Conditional Approval of Maricopa County Air Pollution Control Rule 205 | View Letter >
Aug. 21, 2024 | ADEQ Requests Support for Good Samaritan Remediation of Abandoned Hardrock Mines Act of 2024 | View Letters >
July 15, 2024 | ADEQ Comments on EPA's Proposed Action for AZ's Regional Haze SIP for the Second Planning Period | View Letter >
June 25, 2024 | ADEQ Comments on EPA's "Protection of Visibility: Amendments to Requirements for State Plans Rule" | View Letter >
June 19, 2024 | ADEQ Requests Congress Increase Federal Grants to State and Local Air Quality Agencies to $500 Million in FY25 | View Letters >
May 31, 2024 | ADEQ Requests EPA Extend Comment Period for Proposed Air Quality Regional Haze SIP for the Second Implementation Period | View Letter >
May 16, 2024 | ADEQ Comments on EPA's Proposed Ozone Good Neighbor Plan for AZ | View Letter >
Dec. 21, 2023 | ADEQ Comments on EPA's 2023 Proposed Revisions to the Guideline on Air Quality Models and Enhancements to the AERMOD Dispersion Modeling system | View Letter >
Nov. 17, 2023 | ADEQ Comments on Proposed Amendments to the Air Emissions Reporting Requirements | View Letter >
Aug. 22, 2023 | ADEQ Comments on EPA's Proposed Rulemaking on National Emission Standards for Hazardous Air Pollutants (Primary Copper Smelting) | View Letter >
Aug. 4, 2023 | ADEQ Comments on EPA's Proposed Power Plant Rule | View Letter >
July 13, 2023 | ADEQ Presentation to Joint Legislative Ad Hoc Study Committee on Air Quality and Energy re: State Air Quality Planning — State Implementation Plan (SIP) | View Presentation >
March 20, 2023 | ADEQ Comments on EPA's Proposed Rulemaking on Reconsideration of the National Ambient Air Quality Standards for Particulate Matter | View Letter >