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lions show that the pit will be excavated to a 2H:1 V slope to the bottom of the gravel. As this is be- ing done, a trench around 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 around the mining pit. In this way, water from the mine azea 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 azea, 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 discharge 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 of the mine area, as shown on Map E-1. Once fi- nal depth is reached, the water will go through both sets of berms to get to the pump. All dewatering operations will be conducted so that groundwater flows over the shale bedrock during the entire mining operation. Shale will not be exposed to the air. Mining will occur to no deeper than 1' from the top of the Mancos Shale. There will be no excavations into the Mancos Shale other than the bridge supports as shown. All mining and dewatering operations 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 re- moved from Phase 2 and used to backfill the slopes of Phase 1 from 2H:1 V to 3H:1 V. 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 area 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: SURVCadd Pit Model Report 03/05/2004 Top of dam elevation: 0.0000 Bottom of pond elevation: -23.0000 Cut slope percent grade: 50.00, slope ratio: 2.00 Interior elope percent grade: 50.00, elope ratio: 2.00 Pond Earthwork Volumes Total fill: 0.57 C. F., 0.02 C.Y. Total cut 6,518,127.53 C. F., 241,412.13 C.Y. Pond Storage Volumes Elev Storage (AcreFt) (C.Y.) (C.F.) Area (Acre) - -23.00 0.00000 0.0 0.0 5.245 North Fork Pit Mazch 04 1$