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1 <br /> ' discharge was 520 gpm from the #5 Mine sump, and 307 gpm from the <br /> 7 North Angle. The combined average discharge was 827 gpm. While <br /> ' mining has begun in the E seam (46 Mine) , the discharge is <br /> insignificant and, therefore, is not accounted for in these <br /> evaluations. <br /> ' During August and September, 1989, the discharge from the #5 Mine <br /> sump was significantly increased due to an observed rise in the <br /> water levels in the mine. After approximately one month of pumping <br /> ' at over 2 , 000 gpm, the water level declined and the pumping rate <br /> was decreased to normal levels. Since the apparent source of this <br /> water was in a sealed area of the mine, the cause of the situation <br /> ' could not be evaluated. However, it appears to have been a <br /> temporary situation because this problem has not occurred since <br /> September. <br /> ' WATER QUALITY <br /> ' Summaries of the water quality data for the mine discharge are <br /> presented in Tables 19 through 21. The #5 Mine sump discharge is <br /> NPDES discharge point #003 . The 7 North Angle Discharge is NPDES <br /> discharge point #024. The mine discharge water quality has been <br /> t generally constant through time. A plot of dissolved solids is <br /> presented in Figure 21. It does indicate that the average <br /> dissolved solids in the discharge water have increased from about <br /> ' 790 mg/l in 1982 and 1983 to approximately 890 mg/l in 1986. This <br /> increase may be due to the longwall mining, which was initiated in <br /> May of 1985. This increase in dissolved solids leveled off in <br /> ' 1986. Other than one relatively high reading in 1987, the <br /> dissolved solids are still at approximately 900 mg/l in 1989. The <br /> average dissolved solids concentration for the 7 North Angle <br /> discharge was 831 mg/l in 1989. The flow weighted average <br /> ' dissolved solids concentration for the combined discharge from the <br /> #5 Mine is 880 mg/l. Since the dissolved solids level is still <br /> within the range used in the low flow mass balance prediction, it <br /> ' will not be significantly affected. No violations of the NPDES <br /> permit were detected in 1989. <br /> ' ALLUVIUM <br /> Sediments in the Williams Fork River Alluvium are monitored. Three <br /> ' wells are in the general area of the loadout facilities and <br /> underground discharge sediment ponds. <br /> ' WATER LEVELS <br /> Ground water levels in the alluvium have remained fairly regular, <br /> ' with normal seasonal fluctuations, apparently related to changes <br /> in river levels, and an increase in 1984 due to increased runoff <br /> beginning the spring of that year. Ground water levels in the <br /> ' alluvium are plotted in Figure 22 . A piezometric map for the <br /> Williams Fork Alluvium (December, 1989) is presented in Figure 23 . <br /> ' -2- <br />