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stabilized at just under 1000 mg/L . The plot of dissolved solids presented in Figure 18 <br />shows that the average dissolved solids in the #5 Mine discharge water have increased <br />slightly from about 800 mg/I in 1982 and 1983 to almost 1000 mg/I in 1995. No <br />discharge occurred at discharge poin #003 during 1998. The average dissolved solids <br />concentration for the 7 North Angle discharge continued to hold stable at about 950 <br />mg/I in 1998 as compared to 1285 mg/I in years 1991 and 1992. This trend is related to <br />the accumulation of water in the North Angle Sump location while the pump was out of <br />order. This water was allowed to equilibrate within old workings and subsided longwall <br />panels. The maximum concentration of 1474 mg/I represents this equilibrium <br />concentration and also provides an indication of the expected post mining TDS <br />concentrations in rubbelized zone of underground mine workings. Likewise, this <br />decrease illustrates the effects of flushing upon the TDS concentrations with normal <br />periodic discharge. <br />ALLUVIUM <br />Sediments in the Williams Fork River Alluvium are monitored. Three wells are in the <br />general area of the loadout facilities and underground discharge sediment ponds. <br />WATER LEVELS <br />Groundwater levels in the alluvium have remained fairly regular, with normal seasonal <br />fluctuations, apparently related to changes in river levels. Groundwater levels in the <br />alluvium are plotted in Figure 19. A piezometric map for the Williams Fork Alluvium is <br />C-01-0,s 1998 AHR Page 7 <br />