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Once this work is completed, the excavation of gravel will begin to allow dewatering of the pit. <br />This excavation will begin on the north and west portions of the pit azea, where little overburden <br />occurs. Therefore, no overburden stockpile is needed. This area is called Phase 1. A D-8 or D-9 <br />dozer and/or Cat type 9881oader will be used to push or cant' the gravel to the pit facilities. It is <br />possible that other equipment may also be used in the material excavation. Map E-1 shows two <br />cross-section lines: A-A' and B-B', which are shown on Map E-3 Cross Sections. These cross-sec- <br />tions show that the pit will be excavated to a 2H:1 V slope to the bottom of the gravel. As this is be- <br />ing done, a trench around the outside perimeter will always be dug deeper than the rest of the mine <br />azea. A small gravel berm will be built on the inside edge of the trench azound the mining pit. In this <br />way, water from the mine azea must seep through a sediment bean to get to the trench. A pump lo- <br />cated in the trench will pump the water into the Farnsworth Collection Ditch, which leads to the <br />river immediately downstream of the permit azea, as shown on Map E-1. When the trench itself is <br />being excavated, a sediment berm will be created on either lateral side of the pump, therefore water <br />from the trench must go through these beans to get to the pump. All water discharge into the wet- <br />land will be clean and will be regulated by a CDPHE storm water/process water permit to dischazge. <br />The pump will be installed at the southeast corner of the mine azea, as shown on Map E-1. Once fi- <br />nal depth is reached, the water will go through both sets of beans to get to the pump. <br />Once Phase 1 is mined out, the topsoil and overburden will be removed from Phase 2 and used to <br />backfill the slopes of Phase 1 from 2H:1 V to 3H:1 V. Mining will then continue in Phase 2. Once <br />Phase 2 is mined out, the remaining topsoil and some overburden in the pit will be used to backfill <br />the remaining slope area from 2H:1 V to 3H:1 V. The topsoil from the stockpile will then be used to <br />reclaim the entire upper portion of the area. <br />The gravel zone is approximately 18-25 feet thick, and volumetric computer analysis of the exist- <br />ing and final topography shows the following: <br />North Fork Pit Mazch 04 17 <br />