By Anna Harmon

October 2, 2024 - A number of conservation groups are challenging Montana regulators' approval of a mining expansion at Signal Peak Energy's Bull Mountains coal mine in Montana.

Earthjustice filed a complaint for declaratory relief with the Montana 13th Judicial District Court on 27 September, claiming the state Department of Environmental Quality's (DEQ) environmental analysis of Signal Peak's permit application was insufficient.

The complaint accuses the Montana DEQ of violating the Montana Environmental Policy Act (MEPA) by inadequately analyzing the mine expansion's potential effects on water supplies and cultural resources.

Earthjustice is representing Bull Mountains Land Alliance, Northern Plains Resource Council and the Montana Environmental Information Center in the lawsuit.

The environmental assessment and permit amendment approved by the state DEQ in August allows operators of the Bull Mountains mine to access an additional 12.7mn short tons (11.5mn metric tonnes) of recoverable coal.

Environmental groups claim the Montana DEQ failed to assess the expansion's "cumulative and secondary impacts […] to water quantity, wildlife, unique resources and cultural and historical sites, greenhouse gas pollution, agriculture, worker safety and the community's inevitable transition from coal mining to other, more sustainable sources of revenue", the environmental groups argue in the lawsuit filed on 27 September.

Additionally, DEQ's decision to not prepare an environmental impact statement — which is more comprehensive than an environmental assessment — before permitting the Signal Peak coal mine expansion also violated MEPA because such a statement is required by state agencies if a proposed action is expected to "significantly affect the quality of the human environment", the complaint stated.

The Montana DEQ said it does not comment on active litigation. Signal Peak did not respond immediately to a request for comment.

Signal Peak applied for the permit amendment on 7 November 2023. That came nine months after the US District Court for the District of Montana vacated a federal agency's approval of a different plan to expand Bull Mountains' mining on federal land after the US 9th Circuit Court of Appeals found fault with the US Office of Surface Mining Reclamation and Enforcement's (OSMRE) environmental assessment of the plan. OSMRE has not yet concluded a revised analysis of that plan.