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The mining and reclamation plans are very much related for this gold operation. Since the exact <br />depth and thickness of the gold bearing material is unknown throughout most of the south mining <br />area, a continuous plan for monitoring the amount of overburden removed and gold bearing material <br />sent to the plant so that there is enough backfill material available for the post - mining topography. It <br />is assumed for this plan that the average depth of a cut is 60 feet and that the bottom gold bearing <br />portion is 5' to 15' thick. If the gold bearing portion was 30 feet thick, much more material would be <br />sent to the plant site and there may not be enough material left in certain cuts to provide for accept- <br />able post mine topography. The following items will ensure that no material handling problem will <br />arise: <br />a) Assuming that 20 feet of gold bearing material exists in a total thickness of 60 feet, the expansion <br />of the 40' depth of overburden cut @20% would allow for a replacement thickness of 48 feet. Since <br />the terrain rises appreciably to the east, it would be very easy to flatten the terrain slightly to account <br />for the deficit of overburden. It is very unlikely that the gold bearing material would exceed 20 feet <br />at any location. Past experience on the site does not indicate this will happen. <br />b) The reclamation plan in this area calls for a series of flat areas and slopes in between to allow for <br />the rise in the terrain. If a deficit occurs, the slope to the next bench area could simply be moved to <br />the east, making the lower flat area wider. <br />c) If, for any reason, the gold bearing material exceeded the percentage needed to provide for good <br />reclamation or the amount of gold bearing material sent to the plant could not be sold by the gravel <br />operation, the permit would have to be revised to allow for a portable plant that would move with <br />the mining area, which would allow the waste rock to be delivered to the previously mined out areas <br />adjacent to the plant. <br />d) The operator could also use trucks or set up a conveyor to bring back a portion of the waste <br />gravel to the mined out cuts, if a deficit arose. <br />e) The average thickness of gold bearing material used to determine the material handling calcula- <br />tions is 7.5 feet. See calculations later in this section. If the amount of gold bearing material was <br />Alma Placer Mine 1115 14 <br />