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r <br />MountRoyaleVenturesCashMineHydrology AdrianBrown <br />in the analysis of conditions after mining, the head at the mine nodes is set at approximately #1 Level, <br />where water could flow to the environment if the water level in the mine reaches the #1 Level adit. The <br />head in the mine is set at 7935 ft amsl. <br />RESULTS <br />Three analyses were run: pre mining, during mining, and post-closure. <br />Pre-Mining <br />Conditions were analyzed for the pre-mining period (before the beginning of the 20th Century). In this <br />analysis, the mine was not introduced into the model. <br />The head results are shown in Figure 4a. The water in the rockmass enters at the ground surface, and <br />then flows down into the rockmass, emerging at the toe of the ridge, near Gold Run Creek. <br />During Mining <br />Conditions were analyzed for the period during mining, in which the water level in the mine is held <br />below the #3 Level to allow mining. The analysis was conducted for a drawdown of 350 feet from <br />ground surface, which is approximately the average operational drawdown. The head conditions at <br />steady state are shown on Figure 4b. <br />The modeled inflow to the mine during drawdown was found to be as follows: <br />Flow to mine: 365 cubic feet/year/foot width of mine <br />Effective Width of mine: 600 feet <br />Flow to the mine: 3 gpm <br />This flow is approximately a factor of 2 higher than the observed flow to the mine, reflective of the <br />higher conductivity rockmass near the surface that is drained by the model, but is not likely directly <br />drained by the actual mine. <br />Post-Closure <br />After the mine is closed and a plug installed in the #3 Level Adit (Mount Royale Adit No. 1), the water <br />level will increase until seepage emerges from the #1 Level adit area consistent with historic "pre-law" <br />conditions, and not emergent as a point source discharge. The closure conditions were estimated by <br />setting the heads in the mine to the elevation of the #1 Level (7935 ft msl, 115 ft below collar level), and <br />computing the amount of water that would seep from the mine under these conditions. The head <br />conditions at steady state after closure are shown in Figure 4c. <br />The flow to the mine post-closure is computed as follows: <br />Flow to mine: 157 cubic feet/year/foot width of mine <br />Effective Width of mine: 600 feet <br />Flow to the mine: 1.3 gpm <br />The flow is also expected to be an over-estimate of the flow to the mine; a value of approximately 0.6 <br />gpm is expected, based on the ratio established above. <br />13 <br />1601A-20060911