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minimized by covering the compacted refuse with 30 to 48 inches of the best <br />available non -toxic material. Impacts to the ground water system are not <br />expected to be significant due to the relatively impermeable nature of the refuse <br />and the low water table. <br />The development and reclamation of the cuts and fills in the portal areas should <br />have no impact on the bedrock aquifer system. Recharge of the aquifers does not <br />occur in these areas due to surface water control systems, so possible degradation <br />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 />are 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 area 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 obtains part of the required water supply from the White River <br />Lagoon, as discussed earlier. Approximately 552 ac. ft. per year (601 gpm is <br />pumped from the lagoon to a head tank in the D -Portal area. This is less than one <br />percent of the low flow of the White River. Therefore, impacts are not <br />significant. <br />Recharge of the ground water is not expected to be impacted significantly by the <br />proposed mining operation. The majority of the recharge area for the Mesaverde <br />aquifers is outside of the mine plan area. It is possible that surface fracturing <br />resulting from subsidence could increase recharge to the Upper Williams Fork. <br />However, these cracks, if they occur, are expected to exist for only a short period <br />of time before naturally sealing. <br />Recharge of the White River alluvium by bedrock aquifers is not considered to <br />be significant because of the low transmissivities of the aquifers. The permittee <br />has estimated that total discharge could be 1.3 gpm through bedrock aquifers to <br />the White River, which is less than a tenth of a percent of the base flow of the <br />river. Therefore, the expected change in the recharge capacity of the bedrock <br />aquifers would not be a significant impact to the alluvial aquifer. <br />The surface recharge capacity of the alluvial material in Scullion Gulch may be <br />reduced due to the construction of cuts and fills in the portal areas. This <br />disturbed area is small relative to the total area of Scullion Gulch and therefore <br />impacts are expected to be very minor. <br />Due to the presence of Kenney Reservoir, water withdrawal from the White <br />River lagoon will not cause measurable drawdown in the alluvium at the well <br />field site. The quantity of water that will be pumped is less than one percent of <br />32 <br />