The Montana Department of Environmental Quality (DEQ) announced Friday, Feb. 6, that it has signed an administrative consent order with Montana Resources (MR) to resolve a water backflow incident that occurred in Butte last summer. The agreement concludes DEQ’s enforcement investigation into the event.
The consent order details actions Montana Resources has taken since the incident, including full cooperation with DEQ, coordination with Butte-Silver Bow officials, and a voluntary $1.2 million payment to enhance backflow prevention within the city’s public water system. The order also outlines steps MR must take to obtain DEQ approval for a potable water system on the mine property.
The incident occurred on August 13, 2025, prompting DEQ and Butte-Silver Bow County to issue a Do Not Consume Order for some municipal residents while water quality testing was conducted. Tests confirmed that the city’s main water supply was not contaminated. On August 18, DEQ downgraded the Do Not Consume Order to a Health Advisory for a more limited area. The Health Advisory was lifted on August 25, 2025.
“Montana Resources has worked closely with DEQ and Butte-Silver Bow to address the incident and enhance water safety for the community,” DEQ officials said. “The consent order formalizes these steps and ensures ongoing compliance and oversight.”
The signed agreement marks the conclusion of DEQ’s investigation and establishes a framework for preventing similar incidents in the future.