(KPAX) BILLINGS — Talen Energy, part-owner and operator of the Colstrip Power Plants in southeastern Montana, says the state's $285 million cleanup plan for coal ash ponds at Colstrip is "grossly excessive," and the company will challenge that decision.

At issue is the fate of the settling ponds that contain 6.7 million cubic yards of toxic coal ash associated with Colstrip's two oldest units, 1 & 2, which were retired in 2019.

The Montana Department of Environmental Quality (DEQ) decision last month required Talen to foot the bill to excavate the 330-acre site and relocate the toxic ash to a new, lined impoundment above the water table.

In filing its objection with the state, Talen took issue with the state's preferred alternative and said it received no notice from DEQ about the cleanup decision.

"The Department selected the most expensive and invasive remedy, even though other remedial alternatives met the requirements at lower cost," Talen officials wrote.

Talen's objection also pointed out that earlier, DEQ had indicated that if Talen did the cleanup work itself, $151 million would be adequate.

Colstrip rancher Clint McRae, a member of the Northern Plains Resource Council, told MTN News that Talen's decision to fight the state ruling is disappointing.

"Talen's decision is a blow to adjacent landowners and agriculture and puts hundreds of clean-up jobs at risk," said McRae. "It's time for Talen to exercise responsible development and clean up the mess that they've caused. Excavation is the only way to ensure clean water for the future of Colstrip."

The massive coal ash ponds adjacent to the Colstrip Power Complex have been leaking contaminants for decades, which have proven to be harmful to humans, livestock, and wildlife.

The timing of DEQ's decision last month, and now the objection by Talen Energy this week, triggers a process that will delay any resolution of the issue.

It means the final cleanup decision will come during the new administration of Montana Gov.-elect Greg Gianforte.

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