2014-12-15_PERMIT FILE - M2014043 (2)

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MINING PLAN EXHIBIT D(CONT) will create a hole that will be used as a siltation pond for wash water recycling, that will last for the life of the mine. Once mining ends in Stage 1 it will move to Stage 2 which will be mind in 2 phases . The first will be to begin removing material from the terrace face immediately east of the Plant Site and work east and south on a elevation that is 2 feet above the ground water level in this area until the mine limits have been reached. A near vertical (%: 1) mining face will advance east to west across the upper level until it reaches the setback line. Site investigations indicate the groundwater elevation under the eastern part of the mine is approximately 5072 . So that during the initial phase the floor elevation will be mined at approximately 5074 . Track-hoes, front-end loaders, haul trucks and scrapers will remove material from the working face and floor of the mine. It will be hauled or conveyored to the processing plant . A second slurry wall will be installed at the base of the excavated slope in Stage 2 to seal the lower 15 feet of the deposit so it can be mined dry. This slurry wall will be located approximately 60 feet inside the permit boundary on the north, east and west sides . It will be approximately 5, 075 feet long and have an average depth of 17 ft . Once the slurry wall is in, the second phase of mining, will begin on the eastern side of the lined area and work back to the Plans Site. As mining begins in the lined area the water trapped within the liner will be pumped into the old lake so it returns to the groundwater system. Once the bedrock is reached and adequate room is created on the east side backfilling will begin. The slurry walls will be certified and become liners to block groundwater from entering the excavation areas. This reduces the amount of evaporative loss replacement water needed during mining. This certification will be obtained as soon as possible after installation is complete. If needed, a Temporary Substitute Supply Plan will be obtained from the Office of the State Engineer prior to exposing water and will remain in effect until advised by the Office of the State Engineer that is not needed. No blasting will take place on this mine. 9(Revised 12/15/2014)