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SUNDAY MINE COMPLEX-HYDROGEOLOGIC REPORT <br /> 11.1 General Hydrogeologic Setting <br /> Geologic structure and groundwater and surface water occurrence information presented in the <br /> previous sections allow for a general interpretation of hydrogeologic setting at the SMC. <br /> The presence of broad folds and faulting at, and near, the SMC are expected to affect <br /> groundwater behavior, but the affects may not always be evident due to sparse data. The <br /> impact of mapped normal faults on the local hydrogeology is not known first hand. No workings <br /> appear to intersect mapped faulted areas where saturated aquifers exist, and no observations of <br /> intersected faults suggest these faults are sources or sinks to groundwater. There are no <br /> specific data that have been collected to investigate the hydrogeologic influence of faults in the <br /> area; and, drill hole data were not available to directly examine this relationship. <br /> However, investigatory drill holes (SC 0109, SC-0209, SC-0309 and SC-0809) drilled by <br /> Denison in 2009 to support groundwater information in the area of the Carnation Mine portal <br /> indicated a range of water level elevations from 5,370 to 5,492 ft amsl. These variable water <br /> level elevations could be the result of groundwater compartmentalization due to faulting in this <br /> area (CDM, 2009). There is no direct evidence that faults act as conduits or barriers to <br /> groundwater flow. For the majority of the SMC study area, faulting does not appear to greatly <br /> influence groundwater occurrence. <br /> Denison (2012) presented hydrogeologic cross sections for each mine area at SMC in the <br /> Environmental Protection Plan. For convenience, these figures are included as Figures 7-6 <br /> through 7-9 in Appendix D of this report. The cross sections are conceptual in nature and <br /> project a potentiometric surface from the southwest flank of Big Gypsum Valley to the <br /> southwestern part of the mine workings. There are insufficient data to support the implied <br /> hydrogeologic relationships in these figures, specifically, the existence of a broad singular <br /> potentiometric surface. However, they are useful to better understand potential fault and <br /> formation geometry in the area of the portals. <br /> Stratigraphic dip associated with the Gypsum Valley anticline and the Disappointment syncline <br /> is generally expected to influence groundwater occurrence, gradient, and flow direction. Strata <br /> in the area from the mine portals to the south, where the mine workings are located, have a <br /> general regional strike of N 55°west, and dip of 15° to 18° southwest. Exposed strata of the Salt <br /> Wash Member on the ridge between Big Gypsum Valley and Disappointment Valley is minimal <br /> and recharge by infiltration of precipitation in this outcrop is likely minor. It is suspected that <br /> Western Water& Land, Inc. 38 <br />