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Whirlwind Mine Groundwater Characterization Report <br /> in the Packrat Mine and other mines has been suggested to be seepage from intercepting <br /> exploration drill holes. This was observed in past inspections of the Packrat Mine. This is a <br /> reasonable, if not a partial explanation of some mine water occurrences. Any fractures <br /> connected to overlying saturated units in the Brushy Basin or Burro Canyon may also convey <br /> water into the mines in the study area. <br /> PR Spring is the only natural water source in the study area that directly emanates from the Top <br /> Rim sandstone of the Salt Wash. Its actual point of origin and flow path are unknown. As <br /> discussed in the next section, PR Spring chemistry is somewhat unique, but exhibits radiological <br /> concentrations that suggest at least some of the water may originate from the Salt Wash or that <br /> some of the flow path is within the Salt Wash mineralized zone. As suggested above, an <br /> extensive fracture network within the Salt Wash Top Rim sandstone may be able to produce the <br /> magnitude of flows observed at PR Spring. If such a fracture network exists, it would seem likely <br /> some fractures would intercept at least some of the mine workings and result in mine water <br /> discharge at the surface. In the literature examined for this report, no such fracture system was <br /> noted. <br /> The connectivity of PR Spring with the Packrat Mine has been a topic of interest because of <br /> potential discharge permitting. Work done by USES on behalf of Umetco in 2001, reported that <br /> the spring emanates from a joint in the outcrop of the Salt Wash beneath a gray mudstone that <br /> separates the Top Rim into two separate sandstone units. USES postulated that this mudstone <br /> unit serves as a barrier to vertical downward migration of groundwater from the overlying ore- <br /> zone sandstone to the underlying sandstone unit associated with PR Spring. USES further <br /> stated that any groundwater percolating downward to the mudstone unit was directed to the <br /> northwest toward the Lumsden fault where it would eventually dissipate. <br /> The Packrat Mine is known to have discharged mine water from the portal in the past <br /> (approximately 2 gpm) but has not shown discharge for since 1995 (EFR, 2008a). During active <br /> mining at the mine in the mid-1950's through the 1980's, water collecting in the underground <br /> sumps was pumped to and discharged at the surface. The mine is currently partially flooded but <br /> does not discharge water at the portal/surface. This implies that any inflow into the mine is <br /> balanced to some degree by infiltration into the country rock. It also suggests that sources that <br /> contributed to previous mine discharge have been depleted, or in the case of drill hole seepage <br /> were corrected by Umetco, the last operator at some of the mines. Rajah 49 (also known as La <br /> Western Water S Land, Inc. 42 <br />