A shuttered Koch Industries Inc. coal mine in Colorado operates as a power plant that uses the mine’s methane to make electricity for ski operations in Aspen—demonstrating one way for gassy coal mines to avoid venting a potent greenhouse gas.
But the Elk Creek Mine operations may be difficult to replicate, federal and state regulators say.
Not all companies see the same incentives. A nearby mine owned by a subsidiary of Arch Coal Inc.—the single biggest source of methane in Colorado—already has permission from federal regulators to vent, which is its cheapest option for disposing of the ...