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1.0 Placer Gold Mine Plan <br />1.1 General Plan Gold Mining <br />Past mining history has shown that significant gold placer deposits are found in dips or depressions in <br />the bedrock within the permit area. Good concentrations can also be found in previous locations of the <br />South Platte River channel. Seismic testing of the exact bedrock location (2002) has shown some dips <br />and an older channel location near the west edge of the permit area. Based on this testing and past <br />operations, this area will be targeted for mining. The seismic cross - section locations are shown On Map <br />C -1 and Map C -2. The actual cross sections showing the bedrock as well as the current surface are given <br />in Appendix D. It is expected that 15 to 20 feet of overburden gravel will be excavated and placed in <br />previous pit excavations to get to the lower 5 -10 feet of gravel above the bedrock, which is known to <br />contain the high gold concentrations. In virgin areas, soil from 3" to 9" is salvageable and will be <br />stockpiled as shown on Map C -2. The expected average is 4.5" based on existing cuts of the surface. <br />The areas will be mined in strips of approximately 300 feet long by 150 feet wide with 2H:1 V sideslopes <br />to get to the bedrock. These sequential cuts are labeled on the mine plan. Prior to any mining for this <br />amendment, a gravel berm of a minimum of 8' height, 2H:1 V sideslopes will be created along the <br />Highway 9 ROW for at least a 600' length around the active mining area. This will visually shield the <br />operation from the Highway, as well as minimize noise impacts. Dust should be minimized since much <br />of the mining will take place below the water table, therefore, the material to be mined will be wet. <br />Almost all of the gravel sent to the prep plant will be wet. <br />The operation will resemble a coal strip operation since dozers, loaders and trucks will be used to move <br />the overburden from the area to be mined to the adjacent previously mined area. While the previous <br />mined area is being graded, the lower portion of the gold - bearing gravel will be mined by loader loading <br />into a rock grizzly with 5" openings to ensure that only -5" material enters the porta- ble 36" conveyor <br />system, which will transport the material to the fixed plant location shown on Map C -2. The initial 2 -3 <br />cuts may utilize trucks to transport the gold- bearing gravel to the plant sincethey are relatively close. The <br />current west edge of the 110 area shows a near vertical highwall which must be removed for reclamation. <br />As of the start of 2015, this highwall has been removed. Cuts #3, 46 and 47 will be extended slightly to <br />Alma Place Mine 01/15 10 <br />