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the edge of the stockpile to the top of the mining cut. A small depression of less than 6 <br />inches depth will be cut into this buffer area to prevent topsoil from entering the pit during a <br />storm event. Herbicides are applied annually to control weed growth on the stockpiles. <br />Overburden will also be excavated using scrapers, loaders, and dump trucks. Overburden <br />will be removed from the same three to four acre area and will be used to backfill the <br />existing north slope of the original Vale pit. This area is immediately east of the new <br />excavation area, This slope was mined to a grade of approximately 0.5H:1 V and has shown <br />no signs of any instability. The overburden will be backfilled in lifts and placed at the final <br />reclamation grade of 3H:1V. Once the overburden is removed, the gravel will be mined to <br />the existing depth of approximately 45 feet. Normal water levels are known to be <br />approximately 3-4 feet below the pit bottom. No water will be encountered in the operation. <br />If any is encountered, excavation will stop and the area will be backfilled with at least 2 feet <br />of overburden to cover the water. Gravel extraction occurs in approximately 30 foot lifts <br />and advances from north to south. As of this date, two 30-foot lifts of extraction have <br />occurred across part of the identified mining area. Past mining activities have shown that <br />the nature of the sand and gravel resource is up to a 60-foot thick alluvial deposit. Removal <br />of the resource will most likely not exceed the 60-foot depth. The gravel resource is <br />underlain by Cretaceous age shale. Once the gravel is mined from the first three to four <br />acre extraction area, topsoil from the second area will be placed on the 3H:1V backfilled <br />slope to the east. Overburden will then be removed from the second area and placed in the <br />first, thus starting an ongoing mining and reclamation process. Once the last mining area is <br />reached at the southwest part of the permit area, the existing overburden stockpile of <br />approximately 98,000 cy will be used to backfill the area to 3H:1V and topsoil from the <br />stockpiles will be replaced to cover the overburden to a thickness of 8-12 inches. In this <br />way, disturbance is kept to a minimum and the final reclamation will require less <br />earthmoving. <br />OVERBURDEN/TOPSOIL QUANTITY 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 overburden <br />thickness is 14 feet, 162,000 cy of overburden will be excavated from this area, Therefore, <br />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 />