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35 <br /> determined from the auger hole tests ranged from 0.014 ft/d to 2 ft/d. <br /> Attempts to conduct an auger hole test at AL 4-2 failed because the permea- <br /> bility was too high. In lieu of the auger hole test, this well was pumped <br /> at 30 gpm until an approximately steady state was reached and, from the <br /> observed drawdown, the permeability was estimated to be about 1880 ft/d. The <br /> water-table depth in the alluvial wells ranged from about 4 ft. to 6 ft. <br /> below ground surface and is largely controlled by the water level in the <br /> adjacent stream. <br /> The hydraulic conductivity values reported in this section were used <br /> to estimate the potential effects on the surface and near-surface waters <br /> caused by mining beneath the valley. These computations are presented in <br /> the section dealing with the hydrologic balance. <br /> WATER QUALITY <br /> The effects of the Maxwell and Allen Mines on the quality of the waters <br /> in the Purgatoire River are discussed separately in this section. Following <br /> the discussion of the effects of mining, some comments relative to other <br /> factors influencing the water quality are provided. <br /> IMaxwell Mine <br /> The concentrations of chemical species dissolved in both stream and <br /> mine waters vary from sample to sample for reasons that often cannot <br /> be reliably traced. The variation of water quality makes it difficult to <br /> present the data in a completely meaningful way. Table 5 shows the range <br /> and mean values for several water quality parameters in the Purgatoire <br /> River at Stonewall and in the discharges from the two mines. The Stonewall <br /> data is selected for comparison because the station is upstream of both <br /> mines. Ten data points were averaged for most of the parameters to obtain <br /> the means at Stonewall . The data are from the USGS reports of water quality <br /> at station No. 07124050. The data in Table 5 for the two mines were taken <br /> from 6 analyses of Allen Mine discharge and 5 analyses of Maxwell Mine <br /> If discharge. Commercial Testing and Engineering Co. made the analytical <br /> determinations and copies of their reports are included in Appendix E. <br /> Il The qualities of the mine discharges and the water at Stonewall are <br />