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Recharge of the Upper Sandstone Facies is from seepage into the rather permeable overlying colluvium <br />and alluvium. Flow follows the general surface drainage pattern moving toward Red Wash to the east and <br />. toward the White River to the south. <br />Recharge of the Lower Sandstone Facies, considering the generally impermeable nature of the overlying <br />siltstone, is primarily from the north where these strata outcrop near Highway 40. This outcropping occurs <br />because of the presence of the Red Wash syncline. <br />Intercommunication between facies is suggested at several of the grouped well sites. Water levels <br />between facies are commonly similar suggesting vertical movement of ground water between zones. <br />Communication is not consistent throughout the area as there are also well groups that show significant <br />disparity in their potentiometric surfaces. <br />The tendency for the flow in all three facies to turn southward within one or two miles of the White River <br />rather than continuing toward the axis of the syncline implies that the flow is likely discharging into the <br />White River alluvium. Stereoscopic and aerial observations give some evidence that the White River is <br />following a fracture of fault in the area adjacent to the lease area which may be conveying the deeper <br />groundwater up into the silty alluvium. Red Wash also may be following a fracture zone extending down <br />Red Wash and Spring Creek, which permits water to move more readily to the south once the fracture <br />sandstone is reached. The water table is from 50 to 200 feet under the surface in most of the area, and <br />hence, the only evidence of seeps is where shallow, silty layers impede downward flow from an adjacent <br />drainage. Vegetation along the White River does not show evidence of near-surface, long-lasting <br />• seepage. <br />It is expected that groundwater flows primarily from the middle and upper sandstone facies into the White <br />River Alluvium. However, because of the low permeability of these bedrock formations, this flow is <br />expected to be very limited. A rough estimate of the groundwater flow within the mine boundary as it flows <br />towards the river was made by utilization of the equation Q = KA(dh/dl). In this groundwater flow equation, <br />Q is the flow (gpd), K is the aquifer permeability (gpd/ft2), dh/dl is the hydraulic gradient (ft/ft), and A <br />(estimated at 6,000,000 ftz) is the cross-sectional area of the saturated zone perpendicular to the hydraulic <br />gradient through which the flow occurs (ft2). The permeability, K, was estimated from the results of the <br />aquifer tests in the upper sandstone facies in wells 36-2 and 2-7 to be 0.01108 gpd/ftft . The hydraulic <br />gradient was estimated from the groundwater potentiometric maps prepared from the well level data to be <br />0.02857. The resulting estimate from this data is for a flow of about 1900 gpd (1.3 gpm) through the <br />sandstone towards the river. Of course this estimate is based on limited data and cannot be expected to <br />be accurate, but it does indicate that the aquifer is extremely tight and groundwater flow towards the White <br />River from the upper sandstone formation within the mine plan area is very low. The lower sandstone <br />facies is located below the White River alluvium within the mine plan area. <br />Groundwater flow within the Red Wash alluvium is also expected to be quite low. A rough estimate of this <br />flow was obtained by the same method as outlined in the previous paragraph for the flow within the <br />• Permit Revision #6 (3/2008) II.C-64 <br />