U.S. Department of Energy (2002), Energy and Environmental Profile of the U.S. Mining Industry, Chapters 5-6, report prepared by BCS, Inc. for U.S. Department of Energy, December. ###>U.S. Department of Energy (DOE), Energy and Evironmental Profile of the U.S. Mining Industry, Chapters 5-6, rapport préparé par BCS Inc. pour le DOE, décembre 2002.