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Page 4 <br />May 5, 2009 <br />was conducted to investigate the potential hydraulic connection between groundwaters of the <br />mineralized zones in the Morrison Formation and surface water in Lumsden Canyon. <br />Brief reconnaissance was also conducted in the vicinity of the ore-bearing sandstone (Morrison <br />Formation, Salt Wash Member) outcrop/subcrop area downslope and northwest of the Whirlwind <br />Mine portal. As stated in the September 2008 report, this ore-bearing stratigraphic horizon is of <br />hydrologic importance in evaluating existing and future discharges of groundwater to the surface. <br />Lumsden Canyon <br />The Lumsden Canyon reconnaissance was conducted on December 3, 2008. The goal of the <br />reconnaissance was to investigate the hydrogeology of the canyon and how it may be related to <br />uranium mines and mineralized zones at higher elevations. The intention was to map the occurrence <br />of stream flow, seeps and springs and their relationship to geologic formations. The traverse <br />through the canyon began just below the Lumsden Canyon Mouth sampling site at an elevation of <br />approximately 4,830 ft AMSL and advanced up the canyon to the upper middle fork of the canyon <br />which terminates at Whirlwind Mine and the water treatment plant. This traverse was selected to <br />meet another recommendation of the September 2008 report - to trace the drainage that receives <br />treatment plant discharge water. <br />The return traverse traveled across the Salt Wash Member horizon at the Packrat Mine to the <br />Dutchman Mine dump and down the north-most fork of Lumsden Canyon. This traverse served the <br />purpose of evaluating stream flow gain and loss in the upper north fork of Lumsden Canyon. <br />Observations of hydrological significance are shown on Figures 1 and 2. Key observations are <br />discussed below. <br />No new springs or seeps were identified in the reconnaissance that were not directly related to the <br />streambed. The Lumsden Canyon streambed was dry with the exception of four reaches, as <br />indicated on Figure 1. The uppermost reach first showed water at an elevation of approximately <br />7,070 ft AMSL. This flow appears to consist of runoff and subflow from DP Spring. Surface flow <br />persisted in the streambed from this location to an approximate elevation of 6,470 ft AMSL where <br />surface water infiltrates in a thick gravel/cobble bed adjacent to the Entrada Slickrock Member <br />(Photograph 4, Attachment A). This debris-choked channel partially consisted of waste rock from <br />the Dutchman Mine dump. Discharge was partially measured and estimated at 5 gpm below the <br />Dutchman Mine while sampling on December 4, 2008. <br />Downstream of the infiltration point, at an elevation of 6,381 ft AMSL, tributary water was- <br />observed entering the Lumsden Canyon streambed from the south. This tributary water was <br />assumed to be Packrat (PR) Spring discharge. The tributary was not a well-incised feature; flow <br />occurred in several shallow channels on the hillslope of the canyon and was estimated at 2 to 4 <br />gpm. The tributary water from PR Spring flows approximately 500 ft before infiltrating at an <br />elevation of 6,282 ft AMSL, into an apparently thick deposit of alluvium very similar to the upper <br />infiltration location (Photograph 5, Attachment A). <br />Below this point, several hundred feet upstream of the confluence with the middle fork of Lumsden <br />Canyon, a small showing of surface water appears as seeps emanating from bedrock ledges of the <br />Wingate Formation in the stream bed. This water does not flow more than 20 ft before it either <br />infiltrates or evaporates. Flow here was estimated at less than 1 gpm. A 20 to 30 ft pour off (dry <br />falls) occurs approximately 150 ft below this point and no flow was present at this location. <br />Weans=709.doc