2018-10-11_PERMIT FILE - M2018053

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kBCY (1,000 bank cubic yards)) will be taken from these areas to identify the extension of pay channels until they contact the moraine material. There is also an unassociated exploration target near the Starnes Pit. It is likely that this area is completely mined; however, surface disturbance indicates that some areas may not be completely mined. It is also possible to explore the likelihood that the landslide located south of the Starnes Pit is younger than the placer deposit. If this is the case, grades similar to the Starnes Pit may be present. Drill data indicates that the Starnes Pit produced grades exceeding 20 troy ounces per kBCY at the center of the pit. • Mining Execution Mining will follow methods utilized in the Fairplay-Alma district. Diesel-hydraulic equipment will be used to mine and transport material to trommels and/or horizontal deck wash plants. No chemical processing treatments will be used on site; only water is used in processing gold and gravel. The undersize material (<5/8")will pass through a series of sluice boxes to gravity concentrate recoverable gold. Sluice boxes concentrate gold similarly to how a stream channel would and is termed 'hindered settling.' Hindered settling allows particles to settling by decreasing terminal velocity. When particles are similar in size, classification is also by specific gravity (density of object divided by the density of water). This issue is the principal reason that sluices struggle to capture very small gold particles. The terminal velocity of a particle is determined by the surface area of the particle and the particle's mass. A very small gold particle will behave in a similar manner as a larger less dense sand particle in a hindered settling concentrator. The classic sluice box is an open channel with a flat riffled bottom (Figure 1). Riffles are generally formed by expanded metal on top of"miner's moss" mats, a 3M product normally used for wet area rugs and walkways such as docks. Gravels to be processed are mixed with water in the screening process and flow across the riffles. Riffles generate fluidized beds that allow the hindered settling process to occur. Denser particles such as gold then work their way into the miner's moss. The use of a sluice box is a batch process. Water used in on site sluices will be discharged into settling ponds adjacent to the sluice boxes. The oversize portion of the material Box Creek Placer Mine Greg lxwkki and As iatm PLIA September 2018 D-5