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7.3 Water Balance <br />Sneffels Creek drains a fairly large high altitude basin in the San Juan mountains above this site. <br />There are a number of old mines in this basin. The Atlas Mine portal discharges water high above <br />and south of the Revenue Mine and this drainage drops into Sneffels Creek immediately west of the <br />Revenue tailings /waste pile. This drainage is not part of the permit and will not be disturbed as part <br />of this operation. It is however, being sampled as part of the surface water sampling program. <br />Exhibit G discusses the surface and ground water systems of the mine in detail. Figure G -1 shows <br />the water balance for the underground mine and the surface water system. This water balance can <br />vary significantly with the seasons due to the amount of snowfall and snowmelt that occurs at this <br />site. Figure G -1 is based on predicted mine operation where water emanates from various locations <br />in the Revenue Tunnel, and passes through the buried perforated pipe into the mine waste. Mine <br />water will also be used to supply the mill with water for use in the processing operations. Most of <br />the water in the mill will be recycled but some new water is needed as makeup water. Although it is <br />difficult to predict, it is not expected that future mining will increase water flows out of the mine. <br />Three mine sediment ponds will be used to trap surface runoff water from the surface disturbances <br />at the mine but no mine water will enter these ponds. Since they have been sized to contain the <br />runoff from a 25 year event, the water balance assumes no discharge from these ponds. Ditch <br />diversions are used to divert undisturbed runoff from the operation and direct it into Sneffels Creek. <br />The tailings will be dewatered in the underground mill to a moisture content of 13 -16 %, which is <br />similar to the ore itself before processing. Makeup water may be diverted from the mine water to <br />replace water going out as moisture in the tailings. <br />Revenue Mine August 2012 T -30 <br />