National and local conservation groups are urging the US Forest Service to withdraw its decision to allow Arch Coal to expand its mining operations in a designated roadless area in Gunnison County, western Colorado.
Environmental groups claim that there are loopholes in the Colorado Roadless Rule that could be exploited by mining companies.
According to opposers, loopholes could allow coal miners to build roads and destroy thousands of acres of protected, publicly owned national forest and wildlife habitat in the state.
The Forest Service's proposal would enable Arch Coal to expand underground coal mining operations at its West Elk mine.
As part of the expansion, the company will allegedly bulldoze an extensive road network in addition to scratching dozens of well pads in the Sunset Roadless Area to release methane in the coal below ground.
Defenders of Wildlife federal lands policy analyst Lauren McCain said: "The Sunset Roadless Area is home to black bears and elk, goshawk and beaver, and provides habitat for the imperiled lynx.
"The Forest Service's proposal, which could put miles of road and nearly 50 drilling pads in the Sunset Roadless Area, would damage a wildlife legacy that belongs to all Coloradoans and all Americans."
The court dropped the exception as the Forest Service failed to consider the climate change impacts of providing Arch Coal and one other company with access to up to 350 million tonnes of federal coal.
Mining operations in the region are expected to cause more than half a billion tonnes of carbon pollution from mining and burning the coal.
Existing mines covered by the loophole in the North Fork Valley near Paonia are releasing millions of cubic feet of methane daily, the groups claimed.
Earthjustice attorney Ted Zukoski, who represented the groups in federal court said: "The coal mine loophole is a lose-lose-lose proposition: it's bad for wildlife, bad for hikers and hunters who enjoy Colorado's wild forests, and it's bad for our climate.
"Last year's court decision plugged the loophole, and we'll work to keep it plugged."
The US Forest Service adopted the Colorado Roadless Rule in 2012, which banned road construction on four million acres of the state's wild, remote forest lands.
Image: Mount Gunnison, Sunset Roadless Area. Photo courtesy of Ted Zukoski.