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SUNDAY MINE COMPLEX-HYDROGEOLOGIC REPORT <br /> be classified as "Potentially Usable Quality". However, criteria (d) of this rule, "Domestic or <br /> agricultural use of the ground water can be reasonably expected in the future, considering <br /> background levels of water quality; geologic and hydrologic conditions; the degree to which any <br /> particular types of pollutants present are subject to treatment requirements on water quality; <br /> whether or no pollution arises from natural sources; and other relevant factors", may not be <br /> reasonably achievable because of the moderate depth, low yield, and poor overall water quality. <br /> 12.0 HYDROGEOLOGIC CONCEPTUAL MODEL <br /> The compilation and interpretation of regional, local, and SMC hydrogeological information <br /> presented in this report facilitate the development of a hydrogeological conceptual model for the <br /> SMC study area. A hydrogeological conceptual model is a formulated description of <br /> hydrogeological processes based on observations and the study of hydrological information. <br /> The hydrogeologic conceptual model for the SMC area is focused on the groundwater <br /> occurrence and behavior within the Salt Wash Member, specifically, the Top Rim Sandstone <br /> unit which is the mineralized unit being mined at the SMC. <br /> The SMC is situated on the northeast limb of the Disappointment Valley syncline and the <br /> southwest flank of the Gypsum Valley salt anticline. The Salt Wash Member of the Morrison <br /> Formation which hosts the uranium and vanadium ore deposits and the overlying and <br /> underlying Mesozoic strata strike 55° northwest and dip 15° to 20° to the southwest. <br /> Groundwater within the Salt Wash Member at the SMC is believed to occur in unconfined <br /> conditions at shallow depths and in confined conditions to the west and downdip on the eastern <br /> flank and within the center of the Disappointment Valley syncline. The axis of the <br /> Disappointment Valley syncline trends down the middle of Disappointment Valley, plunging <br /> gently to the southeast. Cater(1955) indicates that the west limb of the syncline climbs more <br /> steeply to the west on the west side of the Dolores River. Therefore, Mesozoic strata dip to the <br /> northeast in this area. The syncline may therefore restrict groundwater movement in the area. <br /> The Salt Wash is minimally exposed on the ridge between Big Gypsum Valley and <br /> Disappointment Valley. Recharge to the Salt Wash is therefore considered minor in this area. In <br /> addition, lateral groundwater inflow from the east is not considered significant due to multiple <br /> block faults that resulted from collapse of salt intrusion associated with the Big Gypsum <br /> anticline. The collapse and dissolution of the salt core (Paradox Member of the Hermosa <br /> Formation) essentially truncated strata that had overlain the area. However, it is conceivable <br /> that in the early stages of salt intrusion and the formation of the anticline, some hydraulic <br /> Western Water& Land, Inc. 50 <br />