2016-10-03_REVISION - M1985022 (3)

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are anticipated other than the piping that ids used to transfer makeup water to the mining area. Since the operation is wholly located on a shallow surficial colluvial/alluvial deposit, the final contour of the surface will not vary significantly from the current contours shown on the Mining Plan map. The only significant change will be the removal of the small ridges and cuts to produce a smoother, more regular final surface. Reclamation of the disturbances related to permitee's operations will be done in such a manner as to blend in as well as possible with pre- law historical disturbances. The ponds may or may not all be removed if a future beneficial use is determined for them. If they are removed,the surface will be graded to produce an average elevation across them. As discussed in the reclamation plan,the area will be seeded at the specified rate with the approved seed mix. As the permitted area has been minimized to the smallest possible area, as a result of State regulations,the entire area currently located within the permit boundary is needed to operate. The mine has been in production for at least 140 years, and the limits of the deposit have still not been defined. At this point, and at the current production rate, the operator anticipates no less than 10 years of ore in sight, and it is likely that the mine might have a life of at least 25 more years. Reclamation of the entire area will be performed at the end of production. Comment 5: The revised Mining Plan discusses how water from the wash plant is managed. Please provide a more detailed description of how water is routed through the three ponds. The description should address how water is routed from each of the ponds and all conveyance structures (pipes, valves and pumps) should be discussed for each pond as appropriate. Also, address how the existing system is managed to prevent the ponds from overtopping and discharging water to offsite areas. Response: As a base, we use the discussion of the water management from the Mining Plan provided by operator dated July 17, 2016. To that discussion, modifications have been made to assist the reader in understanding the water flows and balance. First, the mine has operated at a water deficit since its beginnings. Added to the problem of lack of water,the gravels and soils in the area generally have very high permeabilities, thus surface waters in the area of the placer tend to rapidly infiltrate the surface. In the history of the project, there is no record of any runoff water ever being lost from the mining surface, nor is there any evidence showing that surface flows, containing any mining related materials, has ever occurred. In order to be environmentally friendly, the system has been operated as a closed loop system with the process water being recycled. To make up the water deficit, water rights were secured from Pennsylvania Creek, which is located about a quarter mile to the south. This water is simply diverted to the property whenever makeup water is required. The pipe valve is turned on, the ponds are then filled to the proper operating level, and then the diversion water is turned off. Since this is a placer operation,the water is used to wash the gravels and to segregate different particle sizes and specific gravities of the materials being washed. Reference to the Mining Plan map will help the regulator to understand the following discussion. Beginning at the wash plant, water travels through the plant, and as much of the material is dropped out of suspension there. The finer-grained materials that did not settle out then flow to the Wash Plant Discharge Pipe which leads to Pond 1. The water is discharged from the pipe into the pond where it flows via a dike system that is designed to maximize settling of suspended 2