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III IIIIIIIIIIIIIIII <br />999 <br />Doc Date:1211112001 <br />Figure B-4 in Appendix B shows a steady concentration with time except <br />for three outliers. <br />The HI aquifer has been monitored at well GC1 since 1974. The <br />TDS plot for this well shows a slight increase in TDS for water from <br />this aquifer from recent samples compared to the early values. This <br />increase is natural because mining is several miles from this well. <br />Well GC2 has not been monitored for the last se~reral years, but a <br />recent sample indicates a similar increase in TDS for the Third White <br />Sandstone water as the HI. The third well, GC3, at this site monitors <br />the alluvial aquifer and TDS values from this well have typically <br />varied over a larger range because this aquifer is influenced more by <br />changes in recharge conditions. <br />Well GD1 is the water supply well for the mine and is completed <br />in the 20 Mile Sandstone. The TDS plot (Figure E~-8) for water from <br />this well shows a decline in TDS in 1981 and 1982 and an increase in <br />the last three years, except the 1984 value. The 1984 value is <br />significantly below the other values, but the DSSUM value indicates <br />that the TDS is a good measurement. Additional monitoring is needed <br />to determine if a trend has started. Well GD2 is completed in the QR <br />aquifer below the present mining of these seams in 'the D Pit. The TDS <br />measurements (see Figure B-9) for this well show a fairly steady <br />concentration since 1982. <br />The GE cluster of wells are used to monitor the QR, HI, and <br />Second White Sandstone aquifers (see Figures B-10., B-11, and B-12). <br />TDS concentrations for the QR and HI aquifers in this area have been <br />fairly steady with time with no significant trends. A gradual <br />decreasing concentration with time has been observed in well GE3, <br />except for the most recent value. The DSSUM indicates that the TDS <br />measurement in September of 1985 is good. Sodium wind sulfate are the <br />major constituents which significantly increased in the September <br />sample. These values are significantly less than the concentrations <br />observed prior to mining and, therefore, the increases are due to <br />natural fluctuations. <br />Figure B-13 shows a steady TDS concentration plot for well GF1, a <br />20 Mile Sandstone well. TDS concentrations for this well have not <br />varied as the 20 Mile at well GD1 has. The TDS value for December of <br />1982 is thought to be a lab error because the DSSUM indicates a TDS <br />similar to the remainder of the values. The TDS for well GF2 has also <br />been steady (see Figure B-14). This well is completed in the U <br />aquifer below the R coal seam. The December, 1982 value is thought to <br />be in error because the DSSUM value indicates that t:he TDS is too low. <br />A gradual increasing trend might presently exist inn ground water at <br />this site. The KLM aquifer, which is above ttie QR aquifer, is <br />monitored at well GF3. Results from this well show steady <br />concentrations with time. The H and I coal seams helve recently been <br />3-2 <br />