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MountRoyaleVenturesCashMineHydrology AdrianBrown <br />The water quality of water in the Cash Mine has been measured four times in the past, from different <br />places in the mine. Of these, one reading has been taken from the mine pool. This sample was taken with <br />a bailer from Level 3 of the mine, down the shaft indicated in the composite plan of the mine (Figure 3), <br />and in the cross section along the Cash Vein presented in Figure 4. <br />The chemical results of the Cash Mine Pool sample are presented in Table 2. The water sampled at that <br />time (June 30, 2006) was the accumulated water in the mine, resulting from inflow from approximately <br />the last year. The sample is circumneutral, with elevated sulfate and zinc. This is typical of water that <br />has derived in part from slowly oxidizing sulfide ore in the presence of an excess of calcite or other <br />neutralizing material. As the inflow to the mine during this period is estimated to have averaged 0.5 gpm <br />(based on rate of recovery over- approximately 6 months) the flow through the mineralized veins <br />represents a very slow rate, sufficient to approach saturation in sulfate (limited by gypsum solubility). <br />This appears to be true for the wells upgradient of the Cash Mine (Upgradient Wells, Table 2) as well as <br />for water in mine portals downgradient (Tamany Mine Portal, Table 2). <br />Based on the observation that there is no outflow from the mine during the developmental and <br />operational period, and that the water quality in the mine pool is typical of the water quality in the <br />mineralized veins in the district, it is proposed that the mine area groundwater quality (the "ambient" <br />groundwater quality) be monitored in this case by water pumped from the mine pool, from the Cash <br />Mine dewatering well, completed at a depth of 552 feet below collar elevation (8106.84 ft msl), which is <br />equivalent to the #7 Level of the mine. The well location is shown relative to the overall site area on <br />Figure 1, and relative to the mine area on Figure 3. The completion is shown relative to the existing vein <br />workings in section in Figure 4. <br />3.2.3 Affirmative Impact Statement <br />On behalf of MRV, it is hereby stated. that there is not expected to be any hydrologic communication <br />which would compromise the integrity of future groundwater quality as a result of operations at the Cash <br />Mine. <br />This statement is based on. the above groundwater flow regime during operation, and after operation, <br />which can be summarized as follows: <br />• During operation, all groundwater flow is towards the mine, and water flowing to the mine will <br />be directed to the tailings facility at the mill site for evaporation prior to operation, or <br />consumptive use during operation. No outflow of water from the mine to the environment will <br />occur during operation, so no impact to the baseline quality of water can occur during operation. <br />• After operation, plugging of the #3 Level Adit, and reclamation of the portal areas, there will be <br />no point-source outflow to the surface water system (Figure 4c; Attachment 1). Groundwater <br />flow will reestablish down hill through the bedrock, from north to south towards Gold Run <br />Creek. The groundwater flow will resume approximately its prior flow through the mine <br />workings, which will be partly backfilled with low permeability cemented paste and rock. After <br />the mine backfills, all material will be saturated, and any chemical action within the mine <br />resulting from oxidation will be prevented. The groundwater flow through the mine will return to <br />the quality of the upgradient water, and will not have any measurable impact on background <br />groundwater quality. <br />1601A-20060911 4