The Powder River Basin, a 24,000-square-mile geologic structural basin and topographical drainage, is the single largest coal deposit in the country and provides about 40 percent of the coal consumed in the United States. The basin is the former hunting grounds of the Oglala Lakota tribe and now includes parts of the Crow and Northern Cheyenne reservations in Southern Montana as well as the Thunder Basin National Grassland and Devils Tower National Monument in Wyoming. The two mines at the center of the case, Black Thunder and North Antelope Rochelle, account for approximately 20 precent of the United States’ annual domestic coal production. These are large surface mines that are located within the Thunder Basin National Grassland, which is an important area for recreation and wildlife habitat. The decision of the Tenth Circuit Court of Appeals in favor of Guardians was handed down in September 2017 and requires the BLM to reassess the process for lease-granting to corporate industries, like mines, operating on federal land. However, the court did not order the new leases revoked, which will lead to approximately 382 million tons of annual carbon dioxide emissions to enter the earth’s atmosphere for the duration of four- to nine-year leases. Guardians is asking the court to allow additional remedies in the case and is awaiting a decision.