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conductivity versus time plot for well GBS. Conductivities for well GBS have shown an overall decreasing trend since the end of 1992. Changes in this well are thought to be within the range of natural fluctuation but could have been influenced some by previous mining. Figure B-5 presents the conductivity data for well GC1. Concentrations were very >teady from 1988 to 1990, Followed by a decreasing trend when observing recent field values. Figure B-6 shows some scatter in the conductivity data for well GC2. These changes in conductivity are natural and shows a gradual decrease in conductivity the last several years when considering the field measurements. Figure B-7 presents the conductivity versus time plot for well GC3. As with GC 1 and GC2, this well has also had declining values of field conductivity for the last several years. All changes in the aquifers at the GC site are natural due to the distance from active mining and probably reflect natural variation in ground-water quality resulting from an overall increase in precipitation/rechazge in the last several yeazs. Well GD 1 is a Twenty Mile Sandstone well and has been used as the potable water supply well for the mine and the power plant since 1985. Well GD1(2) is a replacement well for GD 1. It was installed in December, 1992 and is located 27' north and 98' east of GDl. The 1989 through 1994 values have fluctuated, with a mean near 900 µmhos/cm, with a gradually declining vend .% possibly developing. Figure B-9 presents the field conductivity data for well GD2. Conductivities for well GD2 have remained fairly steady the last ten years except for the 1992 outlier. Conductivity in backfill well GD3 is thought to be fairly steady the last fe~v years. The August 1993 and August 1994 field values are significantly lower but are not supported by the laboratory conductivity or TDS. Figure B-10 presents the conductivity data for well GD3. The mining upgradient of well ~J 3-2