Revised On: Sep. 25th, 2026 - 01:59 pm
Summary:
ADEQ is codifying a standardized process for remediating nonpoint source (NPS) pollution from abandoned hardrock mines impacting or threatening to impact streams throughout Arizona. The purpose of the rules is twofold:
- First, it implements a formal program in response to the recommendations from the Arizona Auditor General’s September 2021 performance audit of ADEQ’s water quality programs (Auditor General’s Report). The Auditor General found that ADEQ “has not reduced the total number of impaired surface waters in the State” despite a statutory duty to remediate impaired waters.
- Second, it assists ADEQ in meeting responsibilities under Arizona Revised Statutes (A.R.S.) § 49-203(A)(4), which requires ADEQ to establish a state NPS pollution control program by rule. ADEQ notes that it previously adopted an NPS pollution control rule for livestock grazing at A.A.C. R18-9-501 in 2001. This Notice of Final Rulemaking (NFRM) establishes the framework for a distinct category of NPS pollution, abandoned mines, that was not addressed under that prior rule.
By establishing clear rules and procedures for addressing AML-related NPS pollution, ADEQ aims to reduce pollutants entering Waters of the United States (WOTUS) from abandoned mines, thereby improving water quality and helping to delist impaired waters over time. ADEQ anticipates this rulemaking will not impose any additional burden on the regulated community because remedial actions are primarily funded by § 319 of the federal Clean Water Act.
Documents:
Notice of Docket Opening | View NDO >
Notice of Proposed Rulemaking (published by the Secretary of State) | View NPRM >
Notice of Comment Period & Public Hearing | View Public Notice >
- Comment Period: March 20, 2026 – May 1, 2026
- Virtual Public Hearing:
- Date: April 30, 2026
- Time: 2 – 3 p.m. (Arizona)
- Location: Online via GoToWebinar
Additional Information:
