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Whirlwind Mine Groundwater Characterization Report <br /> Sandstone units in the Brushy Basin were identified in the borehole at depths of 122, 242, 287, <br /> 360, 385, 450, and 474 ft. The sandstones range in thickness from about 7 ft to 37 ft. It was not <br /> indicated in Umetco's report that evidence of groundwater was encountered while drilling <br /> through the sandstone units, nor why certain sandstones were selected for testing and others <br /> were not. However, pumping from the selected intervals was consistently successful with <br /> 60 gallons being pumped before sampling. Assuming that the packer seals were not leaking, <br /> these tests were likely legitimate, but there was no mention of methods to assure packer seal <br /> integrity. The BM00-1 testing proceeded in this manner but no packer isolation tests were run in <br /> mudstone units only, so it cannot be confirmed that groundwater was not present in any part of <br /> the mudstone sequences. Based on Umetco's report, it can be concluded that at least three <br /> Brushy Basin sandstones were groundwater-bearing units. <br /> Exploration drilling conducted by Cotter on Dolores Point in 1996 tracked groundwater <br /> occurrence in the drill holes (see Table 1). Static water levels were measured at certain depths <br /> in each hole; most depths were between 255 ft and 290 ft, but others were at 94, 110, and <br /> 650 ft. The static data were converted to elevations using estimated borehole elevations; the <br /> resulting static groundwater elevations are likely accurate to within plus or minus five feet. For <br /> hole depths between 255 and 290 ft, the estimated static groundwater elevations range <br /> between 7,255 and 7,334 ft AMSL In three of the four holes, static elevations are 7,255, 7,258, <br /> and 7,270 ft, indicating an approximate static elevation of 7,260 ft AMSL for this zone of the <br /> Brushy Basin which correlates well the upper Brushy Basin sandstone zone as recognized by <br /> EFR during their exploration drilling program conducted in 2007. <br /> EFR exploration drilling in 2007 consistently penetrated two Brushy Basin sandstone units <br /> below the contact of the Burro Canyon and Brush Basin (see Table 3). This drilling program was <br /> conducted on Dolores Point approximately 0.75 miles southwest of the Whirlwind Decline portal. <br /> At this location, the approximate tops of the two sandstone zones were at depths of 160 to <br /> 260 ft and 322 to 397 ft, respectively. Of the 14 holes drilled, three holes, WW-07-8, WW-07-9, <br /> and WW-07-10, which were located toward the northern end of the holes drilled, only <br /> encountered one sandstone in the Brushy Basin at depths of 345 to 375 ft—the deeper of the <br /> two sandstone zones. However, the most northern four holes showed two sandstone zones <br /> similar to the southern holes. This is clear evidence that the sandstones of the Brushy Basin are <br /> lenticular in nature, forming discontinuous channel sandstones in the vicinity of the mine and <br /> throughout much of the region. Figures 13, 14, and 15, were included in Appendix D of the EFR <br /> Western Water& Land, Inc. 38 <br />