2019-09-16_REVISION - M1994117 (2)

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concentration circuits is recycled. By recycling most of the water that will be used in the grinding and gravity concentration circuits through the proper use of the large thickener tank (35 feet in diameter by 10 feet high with a water storage capacity of 52,870 gallons of process water) CMC will only need to add about one (1) ton of fresh water(240 gallons)to the flotation concentration circuit for every ton of ore that is being processed. Only the water from the flotation circuit is discharged into the tailings retention pond, while most of the water used in the grinding, classification and gravity circuits is recycled. In other words, when the Gold Hill Mill is operated according to its original mineral processing flowchart,the amount of water actually consumed will be less than one fourth of the water that is pumped from the underground water storage pool into the mill. The original approved Gold Hill Mill Permit further states: "The water consumed in the milling process and lost in evaporation from the tailings pond is not expected to exceed 20 percent of the water used in the mill. The water consumed in the milling process will mainly result from water entrapped in the gravity and flotation concentrates and in the unconsolidated tailings. Because of the altitude and limited size of the tailings pond,only a relatively small amount of water is expected to be lost due to evaporation.Recycling the mill water will reduce the amount of fresh water needed in the milling process, and decrease the quantity of water pumped from Left Hand Creek." The operative word in this description of the milling process is consumed. This calculation estimated that the amount of water consumed in the milling process would be 6,350 gallons of water per day when the Gold Hill Mill was processing 50 tons of ore per 24 hour day. Actual mineral processing operations in the Gold Hill Mill demonstrated that the volume of water consumed was approximately 4,500 gallons of water per day,which amounts to 1,170,000 gallons per year. This is well below the 3,388,850 gallons of water that can be pumped from Left Hand Creek in a dry year, and far below the 7,341,432 gallons of water that can be pumped from Left Hand Creek in a wet year. Exhibit E—Map (Rule 6.3.5): 7) The operator's response to Item no. 3(a) regarding the Mining Plan Maps, included a legal description and revised Figure E-1 for the proposed permit area near Left Hand Creek. These documents show the proposed permit area near the creek to consist of 0.218 acres. This acreage varies from what was proposed in the application for this area(0.256 acres) and from what was shown in this area on the previous E-1 map (0.035 acres + 0.218 acres = 0.253 acres). Please correct and/or explain this discrepancy in the proposed permit area near the creek. Does the operator still request a total permit area increase of 0.797 acres in AM-01, as initially proposed? Or has this value changed since the most recent survey was completed? CMC Response: The original E-1 Mine Plan Map submitted by CMC included an area on the North side of Left Hand Creek that was 0.035 acres in size. This parcel of land was included in the proposed permit area to provide access to the foot bridge that was going to be used to access the Left Hand Creek Pump Station. This was addressed by CMC in its January 4, 2019 Response Letter to the DRMS's Adequacy Review Letter No. 2, when it stated that the foot bridge would not be installed as part of this Permit Amendment. A field survey of this area disclosed a gap 6