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of the regraded Phase 1 and 2 lakes to provide a planting medium of a minimum of 6" depth over approximately 7.5 acres. Since this azea will not be stripped until it is mined and since no other top- soil is available for reclamation, no topsoil stockpiles will be utilized for the operation. The fines from gravel processing will be used as substitute topsoil material in reclaiming all other azeas above water level on the site. The expected raw gravel obtained from the mining of Phase 3 is an average thickness of approxi- mately 18' x 15.1 acres =438,500 cy. Subtracting 30% for naturals leaves 306,900 cy sand and gravel to be sold. This is 460,400 tons. Using an average annual sale figure of 200,000 total tons gravel and asphalt), the life of the Phase 3 reserve will be approximately 2.3 years. The volume of natural fines from Phase 3 to be replaced in the pit is 30% x 438,500 cy = 131,500 cy. It is also estimated that the average silt and overburden in the Phase 3 mining azea above the gravel is 2.5 feet thick. Therefore, the volume to be excavated is 60,900 cy. The initial 1/3 of this overburden will be placed in the bottom of the Phase 21ake or placed for slope backfill on the Phase 2 azea as it is stripped. Once this 1/3 area portion of the gravel is exposed, the gravel will be mined under it. As fines become available from the processing operation, they will be used to back- fill Trench # 1. The total volume required to backfill this trench is 23,300 cy, as described eazlier. Trench backfilling will be in 12" to 18" lifts compacted to 90% of the maximum dry density as tested by a certified laboratory. Trench #2 will remain filled with water as long as mining continues in Phase 3. Subtracting the 23,300 cy needed to fill Trench #1 from the total fines (131,500 cy) leaves 108,200 cy to backfill the slopes of Phase 3 and fill Trench #2. As mining progresses in Phase 3, excess waste material and overburden will be piled up on the floor of the Phase 3 azea and also used to backfill mined out slopes. To backfill the perimeter of the excavation (3420 ft) from a 1H:1V slope to a 3H:1V slope requires 61,300 cy, therefore, 108,200 - 61,300 = 46,900 cy is left over to fill Trench #2. Since only 13,068 cy is needed to fill Trench #2, approximately 33,832 cy is excess material which will be used for backfill in the pit. The extra fill will be used to create slopes of between 3H:1 V and 6H:1 V, as shown in the reclamation plan. The bottom of excavation is expected to be 4438' for a gravel zone of approximately 18-21 feet thick- ness, the backfilling will raise the average level possibly 1.0 feet to 4439'. Since the ground water Gilsonite Pit 9/03 14