 Earthjustice, the Sierra Club, the Center for Biological Diversity and other environmental groups announced a campaign in 2015 against Arch Coal's mine project in the Sunset Roadless Area of Gunnison National Forest.Arch Coal used more than $1 billion in "self-bonding" to guarantee it could pay for its mine reclamation obligations under the Surface Mining Control and Reclamation Act of 1977.After Arch Coal declared bankruptcy, the Wyoming Department of Environmental Quality agreed to accept $75 million in place of the company’s $486 million in self-bonding liability to the state.