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With the proposed permit area potentially being mined in three phases, mining will be integrated <br /> with concurrent reclamation activities. In general, as each pit is mined out and mining proceeds <br /> to the next pit, the mined out pit will be reclaimed with slurry wall installation, grading, and <br /> seeding. <br /> Rough contouring will take place during mining while fine contouring and establishing <br /> vegetative cover will be one of the last steps in the reclamation process. The contour blending <br /> will create a topography that produces a smooth transition from the mined areas and reclaimed <br /> slopes to the adjacent land surface. <br /> It is anticipated that additional mining and reclamation in the proposed permit area will take <br /> approximately 9-12 years total. The rate of mining and reclamation and overall life of the <br /> operation is dependent on several factors including economic conditions. <br /> Mining Methods <br /> Mining methods will include activities typical of sand and gravel mining techniques. However, <br /> additional mineable, marketable material is only expected to be found on the bottoms of the <br /> existing mine pits. Therefore, additional potential mining will occur at 3H:1 V slopes so the <br /> stability of existing reclaimed pit slopes will not be compromised. Earth moving equipment on <br /> the site may include, but are not limited to dozers, loaders, haul trucks, and excavators. <br /> Watering trucks may also be used for dust control and a portable crusher and screens, scale <br /> house/employee/storage trailer, fueling/lubricating station, and generators may be located on-site <br /> as needed. No bulk hazardous materials will be stored on-site. <br /> Since groundwater currently fills the mining pits, the bottom of the pits will be dry mined using <br /> dewatering trenches and pumps. Prior to excavation of each mining pit, the pit will be <br /> temporarily dewatered. Once dewatered, trenches will be cut along the toe of the existing <br /> reclaimed slopes to keep the bottom dry while mining occurs. The trenches will extend into <br /> bedrock. Pumps will be used to remove the groundwater that drains from the deposit and <br /> surrounding alluvium. The collected groundwater will be directed to settling basins within the <br /> pits prior to discharge to the Cache la Poudre River. (see Exhibit C-5, Pre-Mining/Mining Plan <br /> Map). Although complete mining and reclamation of each existing pit is expected to take from 3 <br /> to 4 years, dewatering of each pit will be temporary to limit any off-site impacts. During mining <br /> and reclamation activities, it is anticipated that each pit will only remain dewatered for less than <br /> one year. <br /> Some mobile mining equipment associated with the Home Office Mine (M-1977-39) operations <br /> are located within the proposed permit area. Once the proposed permit boundary is marked on <br /> the ground, materials within the proposed permit area will be removed to the existing Home <br /> Office Mine permit area. <br /> Long-term stockpiles are not anticipated. Mining will only occur when the existing pits are <br /> dewatered, so all stockpiles, topsoil and overburden, will be located in the bottoms of the <br /> existing pits. Temporary stockpile materials created during mining will continually be used for <br /> concurrent reclamation and the stockpiles will likely be disturbed on a frequent basis and seeding <br /> the stockpiles will not be practical during the course of the operation. If stockpile seeding is not <br /> used, surface roughening will be maintained to limit wind and water erosion. <br /> Lamb Lakes <br /> DBMS 112 Permit Application Page 6 <br />