Play Live Radio
Next Up:
0:00 0:00
Available On Air Stations

Colstrip Owner To Withdraw In 2025; Environmental Groups File Lawsuit Over Rosebud Mine Expansion

Four tall stacks billow white steam into a blue sky
Jackie Yamanaka
Yellowstone Public Radio
A set of four smoking power plants stacks at Colstrip Power Plant.

One of the owners of the Colstrip power plant Thursday agreed to financially withdraw by 2025.

The Billings Gazette reports Avista Corp., which owns 15 percent of Units 3 and 4, accelerated its deadline as part of a partial settlement agreement between the utility and multiple intervening parties in its general rate case in Washington state.

Avista also announced it will commit $3 million to a transition fund to become available next April for the Northern Cheyenne Tribe, Rosebud County, the town of Colstrip and labor organizations.

Avista earlier this year announced it would back out of Colstrip’s Units 3 and 4 in 2027, seven to nine years ahead of previous estimates.

Meanwhile, a coalition of environmental groups filed a lawsuit in federal court in Billings this week challenging the proposed expansion of the Rosebud Coal Mine, which supplies coal to the Colstrip Power Plant.

The Montana Free Press reports the groups, led by the Western Environmental Law Center, argue that the U.S. Department of Interior’s approval of the 6,700-acre expansion in June violated the National Environmental Policy Act. They say the agency failed to adequately evaluate impacts to surface water quality, the Yellowstone River and greenhouse gas pollution.

The Western Environmental Law Center filed the suit on behalf of the Montana Environmental Information Center, Sierra Club, Indian People’s Action, 350 Montana and WildEarth Guardians.

The expansion amounts to nearly 69-million-tons of coal and expands the Rosebud Mine’s life through 2038.

The groups say the expansion is unjustified because a majority of the owners of the mine’s sole customer, the Colstrip Power Plant, plan to back out in 2027.

The groups also filed a notice of intent to sue under the Endangered Species Act, alleging the Rosebud Mine expansion would harm pallid sturgeon.