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size, therefore, this area will rise by approximately 4.5 feet. Since the surrounding area is so flat <br />and there is no chance that mnoff from the site could cause any damage to the surrounding indus- <br />trial areas, the only sediment control measure to be employed is a 1' deep trench around the staging <br />area which will grade to the excavation. Sideslopes of this ditch will be 2.OH:1.OV. Gravel extrac- <br />tion will begin in the winter of 2002. Mining will occur from the south to the north and water will <br />be pumped from the excavation to the sediment pond. From the pond, water will discharge to the <br />ditch located on the Fmita Marketing and Management (FMM) property which leads to Reed <br />Wash. FMM has the combined process water/storm water discharge permit for this operation and <br />they are responsible for compliance under the permit. <br />Operations within the pit area will be limited to the hours of 6:00 A.M. to 7:00 P.M. and will occur <br />intermittently throughout any given yeaz. Once the overburden is placed on the staging area, a por- <br />table track scale, scale house, portable crushing and screen plant and portable asphalt plant will be <br />brought to the site and set up in the staging area. <br />Mining of the raw sand and gravel will then proceed in the Phase 1 area. Mining will be done by <br />dozers, front end loaders or excavators within the pit and a ramp will be maintained to the staging <br />area for the equipment. The mined pit slope will be 1.OH:1.OV although this slope will be later <br />backfilled with overburden and naturals to 3.OH:1.OV. Once Phase 1 is mined out, the overburden <br />from Phase 2 will be used to backfill the slopes of Phase 1.1t is also expected that 30% of the raw <br />sand and gravel will be designated as naturals or fines which will not be sold. This material will <br />also be brought back into the Phase 1 pit area for backfilling. Then the gravel from Phase 2 will be <br />mined. This process will be repeated for the remaining phases of the project. The entire reserve <br />consists of 2,379,000 cubic yards of raw sand and gravel and overburden. Using an average over- <br />burden depth of 3.5' over 58.2 acres, yields 328,000 cy of overburden. <br />2,379,000 cy - 328,000 cy = 2,051,000 cy raw sand and gravel to be mined. <br />Subtracting 30% for naturals leaves 1,435,000 cY sand and gravel to be sold. This is 2,153,000 tons. <br />Using an average annual sale figure of 200,000 total tons (washed gravel and asphalt), the life of <br />Gilsonite Pi[ 10/02 7 <br />