A Montana conservation group is urging the state to hold Colstrip power plant ash pond cleanup to the highest possible standard, a move it says would keep 218 workers employed for a decade.
Drawing on its federally funded 2019 study of Colstrip cleanup options, the Northern Plains Resource Council said Wednesday that completely de-watering the power plant’s coal ash ponds and putting the ash in dry storage would do the most to stop groundwater contamination, and keep more than 200 people employed.
An estimated 200 million gallons of contaminated water seeps from Colstrip ash ponds every year. The area’s groundwater is undrinkable. The town of Colstrip relies on drinking water pumped from the Yellowstone River primarily to serve the power plant. A highly concentrated coal ash sludge known as “bottom ash” is the most harmful pollution in the 800-plus-acre pond complex. The contaminants of concern, according to the Department of Environmental Quality, are boron, sulfate, molybdenum, manganese, lithium, selenium and cobalt.
Montana’s Department of Environmental Quality has asked Colstrip operator Talen Energy to consider excavating ash from the Colstrip ponds. Depending on which cleanup options the department agrees to, the cost of the project could be $400 million to $700 million. Those cost estimates, for the cleanup of all three ponds, were produced by Talen and Colstrip’s largest utility shareholder, Puget Sound Energy, according to the department.
Talen Energy hasn’t backed full excavation as its preferred cleanup plan. The Department of Environmental Quality will decide which cleanup measures are most adequate.
“Talen has not selected this option as the preferred alternative in these draft reports, but DEQ is still evaluating the different alternatives to determine what would be most effective,” said Kristi Ponozzo, a spokeswoman for the department. “DEQ factored this into the $400 million to $700 million estimate of costs.”
Northern Plains’ Kate French said the “high and dry” cleanup measures preferred by the conservation group would increase the remediation cost to $900 million.
State environmental officials were working with Talen to change the power plant owners’ cleanup plans for the ash ponds, which collectively store pollution from the four generation units.
“DEQ plans to hold our next annual public meeting late this summer,” Ponozzo said in an email. “At that point, we anticipate having the proposed remedy for the Units 3 and 4 ponds out for public review and we expect to be able to release preliminary information on the proposed plan for the Units 1 and 2 ponds.”