2010-01-21_PERMIT FILE - M2009082 (11)

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r be identified in the field to assure that mining operations will be set back as appropriate. Initially, the topsoil (6"-24") and overburden will be stripped with scrapers and stockpiled in the designated stockpile areas identified in Exhibit C. Overburden will also be used to construct berms and as fill in the reclamation slopes. Overburden and stockpiled topsoil will be seeded as appropriate to prevent erosion. Prior to mining, a dewatering trench will be constructed around the perimeter of each phase. A sump hole will be created at the lowest point of each dewatering trench. The sump holes and dewatering trenches will allow sediment to settle before the water is pumped to the Cache La Poudre River using a groundwater discharge pump in accordance with Colorado/NPDES discharge permit regulations. Pipes transporting the water from the mine will discharge the dewatering water directly into the river, the cottonwood gallery adjacent to the river, an irrigation lateral adjacent to Phase IA (that will not be used for irrigation during mining) and/or the wetlands adjacent to active mining areas to maintain appropriate soil moisture during the growing season. Water may also be pumped into adjoining cells. Drainage swales will be designed when the Final Drainage Report is prepared for Weld County. Water may also be pumped into adjoining cells. When the alluvium is sufficiently dry, front-end loaders will excavate the material and deposit it on conveyors. The mining face will be nearly vertical to 0.5:1 slope. The conveyors will transport the material to be processed at the plant site which is located in the northeast corner of the Parsons Mine site. The plant site contains the crushing, screening, and washing equipment used for the processing of the raw materials. The processed materials will be transported to other sites to be used in concrete and asphalt plants and delivered offsite for commercial and government projects. All surface water within the mine areas will drain internally. The Preliminary Drainage Report prepared for Weld County (see Exhibit G, Attachment G-4) provides details of the conveyance of both off-site and on-site surface water through the site. Direct precipitation falling on a mine cell is collected in the perimeter dewatering trench and pumped out. There will not be any uncontrolled releases of surface water and sediment from mining areas. Storm water collected in the open mine will be managed in accordance with Colorado/NPDES discharge permit requirements. Sediment generated from localized storm water runoff and surface drainage will be managed according to the Stormwater Management Plan, enclosed in Exhibit G (Attachment G-3). Water rights at the site will be used for dust control operations along the roads, stockpiles and berms. The water balance discussed in Exhibit G estimates the gallons per week necessary to limit dust emissions. The water will be supplied using a 2,500 gallon water truck. No explosives are planned to be used. Overburden Topsoil and overburden will be stripped with scrapers or a dozer and placed separately in temporary stockpiles within the permit area limits. The topsoil will be segregated and stored separately from the overburden material as required by Rule 3.1.9(1). The topsoil will be placed in berms around the perimeter of the mine cells and will also serve as visual barriers where appropriate (see Exhibit C). The berms along the plant site and north perimeter will have an average height of 6 to 8 feet tall and are not expected to exceed 15 feet in height; they will have maximum 3:1 (horizontal:vertical) Parsons Mine DRMS 112 Reclamation Permit Application Page D2 of DS