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Whirlwind Mine Groundwater Characterization Report <br /> Whirlwind Mine permit document and are re-presented in this report for convenience. Figure 13 <br /> is a plan map showing the locations of cross sections A-A' (see Figure 14) and B-B' (see Figure <br /> 15). These figures present a schematic model of the Brushy Basin in the vicinity of the <br /> Whirlwind Mine. <br /> Injection of water while drilling these holes was frequently at a depth between 220 and 400 ft, <br /> but two holes were drilled dry (WW-07-8 and WW-07-9). These holes were two of the three <br /> holes that showed only one main sandstone unit. This understandably indicates that the greater <br /> the number of sandstones penetrated in a Brushy Basin drill hole, the more likely groundwater <br /> will be encountered. <br /> Groundwater observations in the Whirlwind Decline in June 2008 after the mine had been <br /> dewatered indicated sources in the Brushy Basin in the upper decline and the lower decline. <br /> Minor seepage in the upper decline was possibly related to the percolation of groundwater at <br /> the colluvium/Brushy Basin contact. However, ribbing (timber supports) at this location <br /> prevented a good assessment of the source of the moisture. The main source of groundwater <br /> contributing to flooding in the Whirlwind Decline is interpreted to be related to a sandstone unit <br /> within the lower Brushy Basin at an approximate elevation of 6,954 ft(EFR, 2022). <br /> Accounting for formation dip, this sandstone correlates with the lower Brushy Basin sandstone <br /> observed in the Umetco borehole BM00-1. Seepage at this sandstone is mostly diffuse, and in <br /> June 2008, the observed flow was estimated at 1 to 2 gpm. Note that seepage from underlying <br /> exposed mudstones and Salt Wash Top Rim unit further down the decline was observed but <br /> believed to be the result of local storage in the rock that had been exposed to flooding in the <br /> decline. <br /> Groundwater production from the Brushy Basin in Monitoring Well W-1, as pumped and <br /> sampled by WWL in November 2021, was at a rate of 0.86 to 1.4 gallons per minute for two and <br /> one-half hours with a drawdown of less than 2 ft. Based on a static depth to water of 73.5 ft and <br /> ground elevation of 7042.53 ft AMSL, the estimated static head elevation for this interval of the <br /> Brushy Basin is 6,969 ft AMSL. The lithologic log of this well indicates sandstone intervals at <br /> 5 to 10 ft, 20 to 45 ft and 110 to 120 ft; most of the rest of the log indicated mudstone, siltstone, <br /> and shale. Groundwater was encountered at 78 ft. Interestingly, no sandstone was logged at or <br /> Western Water S Land, Inc. 39 <br />