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Bull Canyon to the west of the mine site at the base of the Navajo Sandstone where <br />siliceous impermeable sandstone of the Kayenta Formation restrict the downward <br />movement of groundwater resulting in the spring. <br />No data in the area is available to access the viability of the Wingate Formation as an <br />aquifer. However, the formation is an important source of groundwater across the <br />Colorado Plateau. <br />8.3.2 Hydrostratigraphic Structure <br />The geologic structure of the area is also important in predicting the direction of <br />groundwater flow. JD -9 is located on the flank of the Paradox anticline near the axis of <br />the Dry Creek Basin syncline with the geologic formations gently dipping to the south - <br />southwest at 0.008. Groundwater flow directions in the area are controlled by recharge <br />areas and the dip of the rock formations. Both of these factors indicate a similar south - <br />southwest groundwater flow direction. <br />There are no mapped faults within the vicinity of JD -9. There are no map faults or <br />evidence of faulting under stockpiles, future storage areas, or mining areas. There are <br />significant faults associated with the Paradox anticline but these faults are located nearly <br />two miles to the northeast of the mine site. <br />8.3.3 Hydraulic Parameters <br />There is only a limited amount of hydraulic data available for the geologic formations <br />capable of transmitting water at the JD -9 mine area. Consequently, estimates of <br />hydraulic conductivity (permeability) are based on limited site data and reported values <br />for the type of rocks underlying the mine. Reference values for the Entrada Sandstone <br />are from Lohman (1965) while sandstone and shale unit values are from Freeze and <br />Cherry (1979). <br />Due to the remoteness of the region, the nearest available hydraulic information for the <br />Navajo Sandstone comes from northwest of the area in Grand and San Juan Counties, <br />Utah where Lowe et al. 2007 reports moderate permeability values and wells that yield as <br />little as 5 gallons per minute to wells located in fractured portions of the aquifer that yield <br />as much as 300 gallons per minute. Wells in the area penetrate both the Entrada and the <br />Navajo Formations, and combined appear to be the dominant groundwater resource in the <br />area. Lowe et al. (2007) reports that springs discharging from the Wingate Sandstone, <br />ranges from 10 to 240 gallons per minute. <br />O'Connor Design Group Inc. U - 14 <br />