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of the ground water by infiltrating waters is unlikely. The fill material itself is <br />generally of suitable quality as a topsoil substitute except for SAR values which <br />aze up to twice as high as defined in the Wyoming Guidelines for suitability. As <br />water flows through the fill, total dissolved solids may increase due to soluble <br />salts; however, this occurs naturally within the existing ground water region. The <br />fill does not contain materials that create a toxic leachate. Water that infiltrates <br />the fill may reach Scullion Gulch. However, due to the small azea of disturbance <br />relative to the entire drainage basin for Scullion Gulch, this will be a very minor <br />contribution of flow in the creek. <br />The permittee will be obtaining part of the required water supply from the White <br />River Lagoon, as discussed eazlier. Approximately 552 ac. ft. per yeaz (601 gpm) <br />will be pumped from the lagoon to a head tank in the D-Portal area. This is less <br />than one percent of the low flow of the White River. Therefore, impacts will not <br />be significant. <br />Recharge of the ground water is not expected to be impacted significantly by the <br />proposed mining operation. Most of the rechazge area for the Mesaverde aquifers <br />is outside of the mine plan area. It is possible that surface fracturing resulting <br />from subsidence could increase rechazge to the Upper Williams Fork. However, <br />these cracks, if they occur, aze expected to exist for only a short period of time <br />before they seal up. <br />Recharge of the White River alluvium by bedrock aquifers is not considered to be <br />significant because of the low transmissivities of the aquifers. The permittee has <br />estimated that total discharge could be 1.3 gpm through bedrock aquifers to the <br />White River, which is less than a tenth of a percent of the base flow of the river. <br />Therefore, the expected change in the rechazge capacity of the bedrock aquifers <br />would not be a significant impact to the alluvial aquifer. <br />The surface rechazge capacity of the alluvial material in Scullion Gulch may be <br />reduced due to the construction of cuts and fills in the portal azeas. This <br />disturbed azea is small relative to the total azea of Scullion Gulch and therefore <br />impacts aze expected to be very minor. <br />Due to the presence of Kenney Reservoir, water withdrawal from the White River <br />lagoon will not cause measurable drawdown in the alluvium at the well field site. <br />The quantity of water that will be pumped is less than one percent of the low <br />flow of the river. <br />In summary, the impact of mining on the ground water hydrologic system will be <br />minimal, primazily because of the limited amount of ground water that is <br />naturally found in the azea. <br />No significant cumulative hydrologic impacts aze expected as a result of the <br />mining activities at Deserado Mine. The Division finds, in accordance with <br />~3 <br />