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flowing into the workings is equal to the water infiltrating into the surrounding <br />formation (see Map G-3 in Attachment C). <br />Currently, only a portion of the Packrat Mine is accessible due to lack of ventilation <br />and adequate roof control in the mine workings located furthest from the portals. <br />However, inspections of those areas that are currently accessible indicate that Map G- <br />3 (see Attachment C), which was prepared by Umetco Minerals, accurately represents <br />the occurrence of standing water within the Packrat Mine. In most cases, the standing <br />water is only boot deep. The map also delineates those features which were making <br />water in the early 1990s including the 10-Straight Vent Shaft (3 gpm), the La Salle <br />No. 6 Vent Shaft (0.4 gpm prior to backfilling during reclamation), and several <br />exploration holes that were dripping water. Because the total ground water inflow <br />into the Packrat Mine is relatively low (<4 gpm), the water does not fill up the mine <br />or flow out the downdip portals. <br />After the drift connecting the Whirlwind with the Packrat is driven, new mine drifts <br />will be developed primarily to the south and southwest from the existing Whirlwind <br />Mine workings. The drifts will be developed within the relatively flat Top Rim <br />mineralized zone of the Salt Wash sandstone unit. No hydrostratigraphic units will be <br />crossed. The feeder source for DP Spring (lower Burro Canyon Formation) is located <br />hundreds of feet above the mineralized zone while the feeder source for PR Spring <br />(lower Top Rim of the Salt Wash unit) is located below the mineralized zone and <br />mudstone layer. It is unlikely that large ground water inflows will occur in these new <br />drifts because there are no pre-existing declines or vent shafts in this region and no <br />known faults that could serve as ground water conduits. Several unplugged historic <br />drill holes may be intersected as the drifts are advanced, however, most historic <br />exploration operations did not typically drill through 600 feet of overburden as would <br />be the case for the Whirlwind Mine. If open drill holes are encountered, they can <br />usually be sealed relatively easily using a packer and injected grout. <br />The new vent shafts that are proposed for mine development will be cased from top to <br />bottom and grouted through any permeable zones that have the potential to make <br />water. Similarly, the exploration holes drilled in 2007 and any future drill holes will <br />be plugged using bentonite to prevent perched water zones above the mine horizon <br />from flowing down into the Top Rim sandstones of the Salt Wash. With <br />implementation of these measures, we expect that no new potential sources of ground <br />water inflow to the mine will be created. <br />The ground water conditions at the Rajah 30 Mine are different than those present in <br />the Whirlwind Mine because the Raja 30 Mine is located in John Brown Canyon <br />rather than Lumsden Canyon. The drift in the Raja 30 that was sealed by Umetco was <br />driven to provide drainage for the mine from its production shaft to John Brown <br />Creek. Reportedly, over 90 percent of the 15 gpm that flowed from the drainage drift <br />originated from the lower portion of the production shaft where the ungrouted shaft <br />intersected water-bearing sandstones within the Brushy Basin unit. The sandstones in <br />this area are located very close to the recharge area and may be receiving some <br />L-:net•~~ fuels l~eso~~i-c~;4 C;orq~{iraticii7 =1~ L!~lic>n 13ouievaed, Suite fi0() 4 <br />l,al:eiti'c~i~d. C'C~ X0128 ~hr~n~;:.30 ~-i)7~-2 I ~0 <br />