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be used to backfill the existing north slope of the original Vale pit. This area is immediately <br />east of the new excavation area. This slope was mined to a grade of approximately <br />0.5H:1 V and has shown no signs of any instability. The overburden will be backfilled in lifts <br />and placed at the final reclamation grade of 3H:1 V. Once the overburden is removed, the <br />gravel will be mined to the existing depth of approximately 45 feet. Normal water levels are <br />known to be approximately 3-4 feet below the pit bottom. No water will be encountered in <br />the operation. If any is encountered, excavation will stop and the area will be backfilled to <br />cover the water. Gravel extraction occurs in approximately 30 foot lifts and advances from <br />north to south. As of this date, two 30-foot lifts of extraction have occurred across part of <br />the identified mining area. Past mining activities have shown that the nature of the sand <br />and gravel resource is up to a 60-foot thick alluvial deposit. Removal of the resource will <br />most likely not exceed the 60-foot depth. The gravel resource is underlain by Cretaceous <br />age shale. Once the gravel is mined from the first three to four acre extraction area, topsoil <br />from the second area will be placed on the 3H:1 V backfilled slope to the east. Overburden <br />will then be removed from the second area and placed in the first, thus starting an ongoing <br />mining and reclamation process. Once the last mining area is reached at the southwest <br />part of the permit area, the existing overburden stockpile of approximately 98,000 cy will be <br />used to backfill the area to 3H:1 V and topsoil from the stockpiles will be replaced to cover <br />the overburden to a thickness of 8-12 inches. In this way, disturbance is kept to a minimum <br />and the final reclamation will require less earthmoving. <br />OVERBURDEN/TOPSOILQUANTlTY BALANCE -Approximately 98,000 cubic yards of <br />overburden exists in a stockpile from previous mining of the Fetcher and Vale pits before <br />2002. Since the actual mining area added in 2002 is 7.2 acres, and the average <br />overburden thickness is 14 feet, 162,000 cy of overburden will be excavated from this area, <br />Therefore, the total overburden to handle on the site is 260,000 cy. <br />Since the mining face will be excavated to a slope of 0.5H:1 V, and the backfilled slope will <br />be 3H:1 V, the difference is 4500 sq. ft. for a total highwall height of 60 feet. Since the linear <br />distance of highwall for the operation to reclaim is 1730', the volume of overburden needed <br />for the backfilling is 288,000 cy. Since 260,000 cy will be available from overburden, <br />"naturals" or sandy fines from the washing operation will be used to make up the difference <br />of 28,000 cy. Naturals are expected to be approximately 10% of the raw material mined. In <br />many cases, naturals are sold to customers, however, since some are needed for <br />reclamation, the amount needed (28,000 cy) will be stockpiled and saved for reclamation. <br />Approximately 8" of topsoil has been salvaged from the 11 acres of disturbance present <br />before the 2002 permit conversion. This is approximately 11,800 cy. Using an average of <br />10 inches over the remaining area to be mined of 7.2 acres yields an additional 12960 cy. <br />As described earlier, this topsoil will not be entirely stockpiled. Once an area of final grade <br />slope is prepared, some topsoil from the area in advance of the mining will be used to <br />reclaim this slope. <br />