2011-01-03_PERMIT FILE - M2011001 (9)

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temporarily stockpiled outside of the floodway within the designated stockpile area on the south side of the property, as identified on Exhibit C. Once the deposit from the southeast corner has been mined, the topsoil and overburden will be stripped from the center of the cell and the material will be used to reclaim the southeast corner. The center of the cell will then be mined. Following mining of the center of the cell the topsoil and overburden will be stripped from the north end of the cell and the material will be used to reclaim the center of the cell. The north end of the site will then be mined. Upon completion of the mining of the north end of the cell, the area will be reclaimed using some of the overburden and topsoil stockpiled on top of the mining cell at the start of the project. Once the north end of the cell has been partially reclaimed with the stockpiled material, the southwest corner of the site will be stripped of the topsoil and overburden and that material will be used to complete the reclamation of the north end of the cell. The southeast corner of the cell will then be mined and reclaimed with the remaining stockpiled topsoil and overburden. Because the site will be concurrently mined and reclaimed, Lafarge anticipates that there will be no more than 3500 linear feet of exposed slope that needs to be graded for reclamation. There will be no permanent stockpiles at this site; all extra overburden will be used to create undulating shorelines. Overburden and stockpiled topsoil will be seeded as appropriate to prevent erosion. A dewatering trench will be constructed around the perimeter of the bottom of the mining cell and sump holes will be installed. The sump holes and dewatering trenches will allow sediment to settle before the water is pumped to the Cache La Poudre River in accordance with Colorado/NPDES discharge permit regulations. 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 from the Iverson Mine, across the parcel owned by the City of Greeley to the 35th Avenue Mine plant site for processing. No processing will occur at the Iverson Mine. All surface water within the mine areas will drain internally. A Drainage Report will be prepared for Weld County and it will provide 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-2). 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. Topsoil and Overburden Topsoil and overburden will be stripped with scrapers or a dozer and placed in separate temporary stockpiles within the permit area limits as required by Rule 3.1.9(1). All topsoil and overburden stockpiles that are placed above the existing surface will be located outside of the floodway and, Iverson Mine DRMS 112 Reclamation Permit Application Page D2 of D4