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conditions, it is anticipated that it will take approximately five years to mine the Lafarge Brown <br />Property as part of the Greeley 35th Avenue Mine's West Pit. <br />Methods of Mining <br />The typical mining procedure will continue to be as follows. Initially, the topsoil and overburden <br />will be stripped with scrapers and utilized to construct reclamation slopes in adjacent mined out <br />areas. Following stripping of the overburden, the deposit will be dry mined through the use of <br />drainage trenches and pumps. Prior to mining, a dewatering trench will be constructed around the <br />perimeter of the mining cell. A sump hole will be created at the lowest point of the dewatering <br />trench. Water will be pumped to the existing NPDES discharge point via a series of ditches and <br />ponds. The ponds will allow sediment to settle before the water is discharged to the Cache la <br />Poudre River in accordance with Colorado/NPDES discharge permit regulations. <br />When the alluvium is sufficiently dry, front-end loaders will excavate the material and deposit it on <br />conveyors. The mining face will be nearly vertical to 0.5:1 slope. The conveyors will transport the <br />material to be processed at the existing plant site which is located on the east side of the Greeley <br />35th Avenue Mine. <br />A portable aggregate processing plant is used on site for crushing, screening, and washing the raw <br />materials. The processed materials are then used at the concrete and asphalt plants, which are <br />located in the southeast corner of the Greeley 35 b Avenue Mine site, or they will be sold/delivered <br />offsite for commercial and government projects. <br />All surface water within the mine areas will drain internally. There will not be any uncontrolled <br />release of surface water and sediment from the mining area. Storm water collected in the open mine <br />will be managed in accordance with Colorado/NPDES discharge permit requirements. Sediment <br />generated from localized storm water runoff and surface drainage will be managed according to the <br />Stormwater Management Plan, enclosed in Exhibit G (Attachment G-2). <br />Water rights at the site will be used for dust control operations. The Operational Losses paragraph <br />contained in Exhibit G estimates provides information about the estimated annual consumptive use <br />for dust control. The water for dust control will be supplied using a 2,500 gallon water truck. <br />No explosives are planned to be used <br />Overburden <br />Topsoil and overburden from the Lafarge Brown property will be stripped with scrapers or a dozer <br />and stored in separate piles on the mine floor or placed immediately in the reclamation slope. Any <br />extra overburden will be used to create undulating shorelines. <br />Greeley 35th Avenue Mine (M-1977-036) <br />DRMS 112 Reclamation Permit Amendment Application <br />Page D2 of D3