HELENA – The cost of cleaning up contaminated coal ash disposal ponds at the Colstrip power plant could reach $700 million, according to Montana environmental regulators.
The Montana Department of Environmental Quality identified the current estimate of $400 million to $700 million in cleanup costs in a letter to state Rep. Daniel Zolnikov of Billings, the chair of the House Energy Committee.
The agency currently has about $80 million, and the plant’s six owners – Talen Montana, PacifiCorp, Puget Sound Energy, Portland General Electric, Avista Corp. and NorthWestern Energy – are required to pay bonds for the entire cleanup.
Zolnikov told MTN News on Thursday that the committee learned that those bonds will be in place by the end of this year.
“This information really allowed us to understand that different routes of cleanup are being considered. Once a route has been agreed upon, costs of cleanup will be more clearly understood, which will happen by the end of the year,” the Republican wrote in an email.
The ash ponds at the 44-year-old plant have been leaking hazardous chemicals, including boron, lithium and cobalt, into the ground at Colstrip for years. Because of declining coal demand from the Pacific Northwest, the plant’s future is in serious doubt, which has raised questions about the cleanup responsibilities.