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• -8 • Prior to disturbance, and in advance of any of the ~its~ brush is cleared and topsoil is removed and salvaged. Topsoil is stockpiled only if a replacement area is not available in the area, if stockpiled, topsoil is seeded for pro- tection. After topsoil removal, the overburden is drilled and blasted in advance of the pit. Overburden is then stripped by dra_glines and bulldozers. Due to the nature of the overburden after it has been blasted and removed from the pit, the material occupies approximately 25$ more volume than in its original condition. When replaced and regraded, the result will be that the topography of the reclaimed surface will be slightly higher than the original surface (an average of 12 feet). After removal of all coal seams which can economically be recovered, the pits are backfilled and graded by the dragline and dozers, The dragline creates spoil ridges by dumping backfill material from the pit being opened into the mined out pit. Dozers and graders then smooth the spoil ridges and blend them into the existing topography. The applicant also proposes to backfill utility plant waste materials into the mine pits. This material will come from the adjacent Craig Power Plant and will consist of fly ash, bottom ash, and scrubber sludge. Approximately 60~ of the utility waste will be fly ash, 20~ will be bottom ash, and 20~ will be scrubber sludge. A maximum of 1,050 tons per day of the waste will be disposed of at the Trapper Mine with an average of 850 tons/day expected. This is equivalent to an average of 1,050 cubic yards per day of material. This would produce an average annual volume of waste of about 160 acre-feet, after compaction. The applicant estimates that this waste burial process will continue for about 30 years. After final grading of the spoil, topsoil is then placed on the spoil to a depth commensurate with the post-mining land use. Areas are then seeded. Reclamation efforts are monitored to insure success of revegetation on the reclaimed areas. Reclamation, in terms of backfilling and grading, will not be contemporaneous within the context of the time limits of the Rules and Regulations, due to the pit lengths, the need to remove interburden from above recoverable coal seams, and cycling times. The operator has committed to the criteria that there will never be more than four unregraded spoil rows (including the active one) at any one time. Coal mined at the Trapper Mine is used by the Craig Generating Station, immediately adjacent to the permit area on the north.