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Once this work is completed, the excavation of gravel will begin to allow dewatering of the pit. This excavation will begin on the north and west portions of the pit area, where little overburden occurs. Therefore, no overburden stockpile is needed. This azea is called Phase 1. A D-8 or D-9 dozer and/or Cat type 988 loader will be used to push or carry the gravel to the pit facilities. It is possible that other equipment may also be used in the material excavation. Map E-1 shows two cross-section lines: A-A' and B-B', which are shown on Map E-3 Cross Sections. These cross-sec- tions show that the pit will be excavated to a 2H: I V slope to the bottom of the gravel. As this is be- ing done, a trench azound the outside perimeter will always be dug deeper than the rest of the mine area. A small gravel berm will be built on the inside edge of the trench azound the mining pit. In this way, water from the mine area must seep through a sediment berm to get to the trench. A pump lo- cated in the trench will pump the water into the Farnsworth Collection Ditch, which leads to the river immediately downstream of the permit area, as shown on Map E-1. When the trench itself is being excavated, a sediment berm will be created on either lateral side of the pump, therefore water from the trench must go through these berms to get to the pump. All water dischazge into the wet- land will be clean and will be regulated by a CDPHE storm water/process water permit to discharge. The pump will be installed at the southeast corner ofthe mine azea, as shown on Map E-].Once fi- nal depth is reached, the water will go through both sets of berms to get to the pump. Mining will occur to no deeper than 1' from the top of the Mancos Shale. There will be no excava- tions into the Mancos Shale other than the bridge supports as shown. All mining and dewatering op- erations will occur so that water flows over the shale bedrock, not through it, in order to lessen the possibility that selenium concentrations will increase in the water discharged. Once Phase 1 is mined out, the topsoil and overburden will be removed from Phase 2 and used to backfill the slopes of Phase 1 from 2H:1 V to 3H:1V. Mining will then continue in Phase 2. Once Phase 2 is mined out, the remaining topsoil and some overburden in the pit will be used to backfill the remaining slope azea from 2H:1 V to 3H:1 V. The topsoil from the stockpile will then be used to reclaim the entire upper portion of the area. The gravel zone is approximately 18-25 feet thick, and volumetric computer analysis of the exist- ing and final topography shows the following: North Fork Pit March 04 1 ~