2001-12-07_REVISION - M1983067 (26)

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• ~ks and Gesso, LLC and approved slope stability analysis, mining will be completed at a 0.5 to 1 slope. In the event that a 0.5 to 1 slope is not possible, the Applicant will mine at the maximum slope allowable by the slope stability analysis. The plant site will be stripped of any remaining topsoil and overburden. The upper raw materials will be 'benched down" to near the groundwater table with front~nd loaders. This technique will allow a large hydraulic excavator to mine the remaining materials to shale. Some raw material may be loaded directly into off-road haul trucks for transportation to the processing plant. However, these quantities are expected to be minimal. Earthmovino Oaerations -Rule 6.4.4(b) Earthmoving operations will begin with general site cleanup, including removal of fences and incidental agricultural refuse. Trees, shrubs and other excess vegetation will be grubbed and removed prior to stripping operations. The topsoil first stripped will be stockpiled around the perimeter of the site in the form of a screening berm. The screening berms will be planted with the seed mix referenced in Exhibit E. During subsequent stripping operations the Applicant will spread topsoil stripped from one area directly on other areas being concurrently reclaimed. Excess topsoil and shale materials not utilized as slope bar~ll material may be sold off-site. Water Diversions and Imooundments -Rule 6.4.4(c) Stormwater from all areas of surface disturbance will be directed toward the mine's dewatering systems via grading and shallow ditches. After the water is clamed and the sediments collected, water will be discharged to the South Platte River. An NPDES permit (No. CO-0038512) was issued for the site on January 18, 1982. Discharge from the site will comply with this previously approved permit. The approved permit can be found in Appendix 1. Aggregate processing water will be separate from the de-watering and stormwater systems. With evaporation and product moisture losses there will be no need to discharge processing water. Moreover, some de-watering discharges will be diverted bads to the processing water system. The tailings pond at the southern end of the property will be maintained below existing grades so that any precipitation will be retained in this area. The slurry wall will be constructed before any penetration of groundwater takes place. At the onset of mining below groundwater, de-watering quantities will be relatively high. However, as the water table within the confined mine area draws down, the dewatering quantities will decrease until the residual groundwater in the deposit is pumped out. While the amount of seepage allowed by the State Engineer's performance standard could be more than double the annual net evaporative loss, we aMidpate a net loss of water between seepage and Stapecoech Mine - Ftepuler 112 Pormk Ot Od5 Moblb Pient6i ConaeOe Ina 7 November. 2001