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Page 8 May 5, 2009 <br />The minor groundwater production in the shallow portion of the decline may be related to groundwater <br />seepage from surface colluvium that may be restricted at the contact with the Brushy Basin but <br />transmitted by secondary porosity (fractures) in the unit. This seepage, although observed during the <br />December 2008 inspection, is minor and does not appear to flow a significant distance on the mine <br />floor. No surface water appears at this location. In drought years, this seepage would probably decrease <br />or dry up. <br />Groundwater seepage rates from the Brushy Basin sandstone could not readily be quantified due to the <br />diffuse nature of the seepage into the reworked floor materials. Visible flow in the sump, which <br />receives water from the drainage collection system, was estimated to be between 2 and 3 gpm during <br />the December 2008 inspection. As interpreted in the September 2008 report, the Brushy Basin water <br />appears to have had persistent flow over a long period of time - nearly 30 years. <br />Other data collected by EFR indicate that the lower Brushy Basin sandstone is groundwater bearing. As <br />postulated in the September 2008 report, this unit is likely laterally continuous and/or possibly <br />connected to sand units higher in the geologic section. This mine-water occurrence will likely continue <br />to discharge into the mine in the future. Recharge to this sandstone unit may occur through vertical and <br />lateral influx of surrounding rock units; the origin of which is from minimal outcrop exposure in areas <br />on Beaver Mesa to the west and south of the mine. Open historic boreholes may also facilitate recharge <br />from upper aquifers. <br />The persistence of groundwater seepage from the Salt Wash Member (upper sandstone) as observed in <br />the ore-bearing drifts of the mine will be evaluated with time. The older workings and the outlying <br />unmined rock had been flooded and potentially recharged by the flooded mine for approximately 25 <br />years prior to reopening the decline. Other data presented by EFR indicates that the Salt Wash <br />Sandstone is dry or of "insufficient permeability" (Umetco permit documents on borehole BM-001) to <br />yield groundwater to open boreholes. Current seepage from the recent workings may reflect ambient <br />groundwater conditions or discharge of previously recharged water from the time the mine was <br />flooded. Also, the local groundwater hydrology has likely been affected by other mine workings and <br />boreholes in the area. The assessment of groundwater in the Salt Wash Member within the Whirlwind <br />Mine will be further evaluated as mining activities progress. <br />An examination of Tables 1 and 2 do not show broad chemical concentration ranges between datasets <br />collected in June and December 2008 at the sampled sites. Field parameters for the Whirlwind mine <br />sites fall in a relatively narrow range, with the exception of the local variation in pH in the sump. As <br />suggested earlier, this is believed to be due to the effects of leaching from the shot-crete applied to the <br />drift walls and back. The June "drift pool" location is thought to be near the December "10000" tunnel <br />location. The lower pH of 7.9 measured in the drift pool in June may be a function of how well the <br />mine was being ventilated during the measurement. pH will vary with oxygen and carbon dioxide <br />partial pressure. <br />If needed, the relationship of the Brushy Basin Member groundwater and water emanating from the <br />Salt Wash Member in the new drift areas could be assessed if the waters were collected separately and <br />analyzed for unique chemical signatures. <br />Surface Reconnaissance <br />Lumsden Canyon Hydrology <br />The reconnaissance of Lumsden Canyon resulted in several general observations and <br />interpretations. It must be recognized that the observations of December 3, 2008 do not apply for all <br />Weans032709.doc