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<br />to a finer grind than the ore that was processed and discharged <br />by former operators of the mill. By grinding to a fiber mesh, <br />metal recoveries will greatly increase which will limit the <br />amount of heavy metals discharged by the mill. Also, by <br />installing a Final Clean-up flotation cell to remove all pyrite <br />from the mill tailings, the tailings discharged from the Golden <br />Gilpin mill will contain far fewer contaminents than tailings <br />that have been discharge in the past. As a result, the quality <br />of they ground water in the Golden Gilpin tailings should actually <br />improve over a period of time. <br />A characteristic of flotation recovery is that it operates at a <br />pH of approximately 8.2. Therefore, the elevated pH of the mill <br />process solution will have a neutralizing effect on the low pH <br />ground water that underlies the existing Golden Gilpin mill. <br />The Cramp Dresser and McKee soil scientist that logged the ground <br />water test hole recorded a number of soil parameters of the drill <br />hole cuttings. These results are also shown on an enclosed <br />table. <br />DEFICIENCY RESPONSE 5 <br />A. The design for transferring solution from one pond to another <br />is shown on the enclosed figure. By using this solution transfer <br />design, no short circuiting of the process solution in the mill <br />treatment pond will occur. <br />B. In the event that the limestone becomes coated with iron <br />precipitates and the pH adjustment capabilities of the limestone <br />becomes reduced, new limestone will be added to maintain a <br />solution discharge pH of approximately 7.0. <br />C. CCCM currently intends to fire the peat to obtain an ash <br />product. The resulting ash will be backfilled into the Bates- <br />Hunter mine. <br />D. As discussed, the pH of the discharged mill solution will be <br />approximately 8.2. Depending on when the pH of North Clear Creek <br />as it flows by the Golden Gilpin mill is taken, i.e. during <br />periods of high or low flow, the pH of North Clear Creek can vary <br />from a low of 5.5 to a high of approximately 6.5 (CCCM tests). <br />CDM test water near the Golden Gilpin Mill and obtained a pH <br />reading of 6.2 (see enclosed table). The discharge of treated <br />process solution with a slightly elevated pH will only serve to <br />improve the water quality of North Clear Creek by adjusting the <br />pH of t~orth Clear Creek to a more neutral pH. <br />DEFICIENCY RESPONSE 6 <br />CCCM will commit to provide MLRD with a copy of the Water Quality <br />Control. Division discharge permit when the permit is issued to <br />CCCM. <br />2 <br />