Leonardite mine looks to operate through ‘52

DOUGLAS (WNE) — Black Hills Lignite, LLC of Denver filed for a permit with the state Department of Environmental Quality for the continued mining of leonardite approximately 25 miles north of Glenrock.

The operation is expected to continue through 2052.

Converse County Commission Chairman Jim Willox on March 2 characterized it as a “small expansion.”

“There’s nothing unusual about it, just a continuation of what they do out there already,” he said.

Willox said the company will complete reclamation immediately after the mine work.

The proposed mine area will be west of 55 Ranch Road / Converse County Route 23. The proposed operation is set to begin in April, according to a public notice from WDEQ.

“When we mine, we start the reclamation process immediately. We only mine 3-4 feet deep,” said Black Hills Lignite Mining Manager Darin Klewsaat. “Leonardite’s primary use is agriculture as it improves the soil. (It) is also used as an oil and gas drilling fluid additive as it reduces viscosity and strength of gels as well as a dispersant and fluid loss agent.”

Klewsaat explained the leonardite mining method begins with the separate stripping of topsoil and overburden, then stockpiling that separately a distance away from the area to be mined.

Overburden is directly backfilled.

Once complete, the former mine areas undergo the reclamation process, including re-contouring, grading, top-soiling and seeding.

This story was published on March 5, 2025.