2009-11-30_REVISION - M2000156 (7)

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6.4.4 Exhibit D — Mining Plan Mining Methods The mine plan has been divided into two Phases for the purpose of bonding each phase separately. Phase 1 is divided into two mining Cells and Phase 2 is divided into 5 mining Cells as shown in Exhibit C -2. Mining is expected to generally proceed in the numeric order assigned to each Phase and Cell. The sand and gravel deposit is overlain by 6 " -8" of topsoil followed by 6 -8ft of overburden material, which will be removed by scrapers prior to excavation of the sand and gravel. The excavation typically utilizes track mounted excavators, but may use front end loaders as well. Excavators or loader transfer the sand and gravel to offroad haul trucks, which then transport the material to the processing area. The operation will typically open up and work an area of 5 -10 acres at a time. Earthmovina Earthmoving begins by stripping the upper 6 " -8" of topsoil, which will be placed in discreet stockpiles for use in final reclamation. The initial excavation for any given mining cell will occur in areas designated for backfilling. This will allow for direct replacement of overburden as stripping occurs in the next adjacent area. The initial excavation for any given cell will require stockpiling of overburden. The maximum volume of overburden stockpile will not exceed 150,000 yd at any one time. Stockpiles associated with processing and the HMA plant (finished product and pit run) will occur in addition to the overburden stockpiles and at larger volumes (150,000 yd' — 250,000 yd'). Water Diversions and Impoundments Trenches will be excavated at the toe of each cell wall to expose groundwater, which will be pumped to a sediment pond prior to discharging to the Big Thompson River. The existing irrigation system is owned by Coulson Excavating Co, Inc. and consists of surface irrigation pipe for sprinkler irrigation. The piping will be disassembled prior to mining and will not be re- installed after mining is complete. Timetable The mine plan is expected to generally follow Table 1, however the timetable may vary according to market conditions.