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gravel and asphalt), the life of the Phase 1 reserve will be approximately 2.1 yeazs. The actual life <br />may fluctuate somewhat in response to supply and demand, fluctuations in mining depth, etc. <br />The volume of natural fines from Phase 1 to be replaced in the pit is 30% x 398,000 cy =119,400 <br />cy. No overburden is available for backfilling since the clean overburden was placed in the staging <br />azea and the contaminated overburden was placed on the FMM property off the permit area. The <br />backfilling of fines to a minimum final slope of 3H:1 V will occur on an ongoing basis. <br />To backfill the perimeter of the excavation (3020 ft) from a 1H:1 V slope to a 3H:1 V slope requires <br />54,000 cy, therefore, 119,400 - 54,000 = 65,400 cy is left over and must be filled in the pit. The <br />extra fill will be used to create slopes of between 3H:1 V and 6H:1 V, as shown in the reclamation <br />plan. The bottom of excavation is expected to be 4438' for a gravel zone of approximately 18-21 <br />feet thickness, the backfilling may also raise the average level possibly 1.0 feet to 4439'. Since the <br />ground water level is expected to be 4448-4449', this would leave a lake of approximately 9.0-10.0 <br />feet depth. <br />Phase 2 Minine <br />When Phase 1 is mined out, the sediment pond will be excavated as part of the Phase 2 mining area, <br />while still leaning a berm of 25' top width between Phases 1 and 2. The mined out Phase 1 azea will <br />then act as the sediment pond for the site. Then the gravel from Phase 2 will be mined and all pit <br />water will be pumped into the Phase 1 lake. The discharges into Trench # 1 and the NPDES pipe to <br />the River will be adjusted slightly from the original sediment pond to the new Phase 1 lake. <br />The expected raw gravel obtained from the mining of Phase 2 is an average thickness of approxi- <br />mately 19' x 10.8 acres = 331,000 cy. Subtracting 30% for naturals leaves 231,700 cy sand and <br />gravel to be sold. This is 347,500 tons. Using an average annual sale figure of 200,000 total tons <br />(gravel and asphalt), the life of the Phase 2 reserve will be approximately 1.7 yeazs. <br />Gilsonite Pit 9/03 12 <br />