In June 1975, Blackfoot River floodwaters breached the tailings impoundment at the Mike Horse mine near Lincoln, releasing approximately 200,000 cubic yards of metal-bearing tailings. Fine-grain metal-laced tailings flowed at least 10 miles downstream, covering the streambed, poisoning the water and destroying the native westslope cutthroat trout fishery in the upper river.
Last week, Asarco, the company mainly responsible for the cleanup of the breach and removal of the Mike Horse Dam, filed for Chapter 11 bankruptcy protection.
“It’s not good news, certainly,” says Matt Clifford, staff attorney for the Missoula-based Clark Fork Coalition. “It was anticipated that sooner or later this would happen. I think this heightens the need at this point to get the other potentially liable party to the table, and that’s Arco.”
According to Clifford, Arco inherited responsibility for the mine when it merged with one-time mine operator the Anaconda Copper Mining Company, the company that owned and operated the mine at the time of the 1975 breach.
What, exactly, Asarco’s bankruptcy means for the cleanup of Lower Mike Horse Creek, Bear Trap Creek and the Blackfoot River is unclear at this point.
“I think it will [have an impact],” said Amber Kamps, Lincoln district ranger for the Helena National Forest, on Monday. “I don’t have any comment regarding the bankruptcy, and I don’t know what that means for all of the work we have been discussing.”
Kamps says the copper giant was supposed to begin preparing two environmental and engineering cost assessments (EECA) this fall, one for the dam and tailings impoundment and one for the remainder of the cleanup below the dam. The documents would provide a road map for what needs to be done to clean up the mess and how much it will cost. Kamps said she hasn’t spoken to Asarco officials since the bankruptcy filing.
Meanwhile, cleanup of Asarco’s environmental messes across the West have stalled while officials try to sort out what to do next.