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this plan that the average depth of a cut is 60 feet and that the bottom gold bearing portion is 5' to 15' <br />thick. If the gold bearing portion was 30 feet thick, much more material would be sent to the plant site <br />and there may not be enough material left in certain cuts to provide for accept- able post mine topography. <br />The following items will ensure that no material handling problem will arise: <br />a) Assuming that 20 feet of gold bearing material exists in a total thickness of 60 feet, the expansion of <br />the 40' depth of overburden cut @20% would allow for a replacement thickness of 48 feet. Since the <br />terrain rises appreciably to the east, it would be very easy to flatten the terrain slightly to account for <br />the deficit of overburden. It is very unlikely that the gold bearing material would exceed 20 feet at any <br />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 the <br />rise in the terrain. If a deficit occurs, the slope to the next bench area could simply be moved to the east, <br />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 the <br />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 gravel to <br />the mined out cuts, if a deficit arose. <br />e) The average thickness of gold bearing material used to determine the material handling calculations is <br />7.5 feet. See calculations later in this section. If the amount of gold bearing material was lower than 4.0 <br />feet in thickness, the operation would likely not be profitable since the overburden to gold bearing <br />ratio would be too high. Therefore, in these areas, no mining would occur. In the very unlikely case <br />that 4' to 6' of gold bearing material is profitable over a large area, there may be a slight surplus of <br />material. Using 5' of material, the remaining overburden of 55' would swell at 20%, resulting in a <br />thickness of 66 feet. This increase of 6' is not significant and would be handled by simply having <br />slightly greater amounts of slope areas instead of flat areas in the reclamation plan. <br />Also, over time, the 20% swell would likely shrink to 15%, keeping the volumes the same after re- <br />moving the 5' of gold bearing material. <br />Alma Place Mine 01/15 12 <br />