Surface Mining - Hearings before the Subcommittee on Minerals, Materials, and Fuels of the Committee on Interior and Insular Affairs United States Senate Ninety-Second Congress First Session on S. 77, S. 630, S. 993, S.1160, S. 1240, S. 1498, S. 2455, and S. 2777 - Serial No 92-13 Part 3