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46N 17W 20 SWSW Last Chance Mesa <br />Reservoir 500 ft higher than Last Chance Mine <br />46N 18W 14 SWSE small and Isolated by Wild Steer Canyon <br />46N 18W 24 NENE stock and & dam See water rights table <br />46N 18W 24 SENE stock pond fed by well well not registered <br />(b) Map C-8 is a geologic map which shows the strata and aquifers within two miles of <br />the site and includes a stratigraphic column in the explanation. The only spring listed in the table <br />above apparently sources from sands within the Brushy Basin shale member in the upper part of <br />the Morrison formation. <br />In some areas, the lower member is an aquifer, but on this mesa with many mine workings <br />perched several hundred feet above the Paradox Valley and cut by numerous steep canyons, the <br />potential aquifers are dry. It is found within the Salt Wash sandstone member of the Late <br />Jurassic age-Morrison formation which outcrops at the mine site. Two monitoring wells <br />penetrated this section and did not find a functional aquifer. Below the Morrison aquifer, shale <br />and mudstone of the Summerville formation acts as a confining unit separating the Salt Wash <br />sandstones from potential aquifers within the older Entrada sandstone, Kayenta formation, and <br />Wingate sandstone. <br />(c) The Salt Wash sandstone member of the Late Jurassic age-Morrison formation <br />outcrops at the mine site (Carter, 1953). Sandstone predominates within this member and is <br />interbedded with shale, mudstone and a few thin lenses of dense limestone. The sandstone <br />consists largely of sub-angular to sub-rounded quartz grains. <br />(d) The Salt Wash sandstone member is cut by several high-angle west-northwest <br />trending faults within the project boundary and across Davis Mesa where the mine site is located. <br />No information is available regarding the fracture systems at the mine site. <br />(e) There is little information available regarding the hydrogeology of the Davis Mesa, <br />but the Last Chance Mine is dry. A description of those geologic strata that have the potential to <br />transmit groundwater is presented above in sections (b) and (c). <br />(9) Groundwater Quality Data <br />(a) There are no present groundwater uses within two miles down-gradient of the <br />proposed project. Four industrial water wells are owned by Energy Fuels at their Pinon Ridge <br />Mill Site about two miles east of the mine. All these wells are in the Paradox Valley to the east <br />and northeast of the mine site. They apparently tap the groundwater aquifer within the Upper <br />Triassic-age Chinle formation which is considerably below the mining zone of the proposed <br />project and separated from it by the Summerville formation confining unit, and the Entrada, <br />Kayenta, and Wingate formations. <br />One spring is found within two miles of the mine project site. It is located in the NW'/4, SW'/4, <br />Section 18, T46N, R17W. It is located over a mile to the south of the site, its source is the <br />Brushy Basin shale member of the Morrison formation which is structurally above the site <br />bedrock. Water has not been observed flowing from the spring, but vegetation suggests shallow <br />seasonal groundwater. <br />Last Chance Mine - April 2009 T-4