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. The flow data for WF-2 was historically provided by the USGS, however, monitoring of [he Williams Fork stations was discontinued in 2001. Historically, comparisons between up gradient site WF-1, and down gradient site WF-2, have not show any stream depletion impacts from mine dewatering. Summaries of WF-1 and WF-2 water quality data aze presented in Tables 13 through 16. A plat of upstream and downstream dissolved solids measurements for the river is presented in Figure 8. The data indicates that the surface water quality does not show any significant variation from expected values. The comparisons of data from the upstream and downstream station on the Williams Fork River indicate that there is no detectable effect of mining on river water quality, As expected, dissolved solids decrease with increasing flow rate in the rivers, due to dilution from runoff. 3.2.2 Springs One spring on the mine site azea is being monitored under TC, the No. 1 Strip Pit Dischazge. The No. 1 Strip Pit Dischazge is a CDPS monitoring point (Outfall 022 or 1SP). There aze a few other springs and local pem~anent "damp spots" in the azea; however, [heir combined flow is normally less than 10 gpm and is therefore not significant. The POR dischazges for the No. 1 Strip Pit aze presented in Figure 9 and the 2003 discharge measurements aze presented on Figure ] 0, respectively. The dischazge from the No. 1 Strip Pit increased significantly in 1989. This may have been due to seepage from the ditch that conveys the 7 North Angle dischazge. The 7 North Angle dischazge began in January of 1989. However, dischazge rates from 1990 through 2003 appeaz lower. Nevertheless, snowmelt and ditch seepage both appeaz to have some influence on the No. 1 Strip Pit dischazge, as the dischazge typically drops to just a few gpm from January though May with a small peak typically in Mazch coinciding with spring runoff. The sumrnary of the water quality data for the spring is presented in Tables 17 and 18. A plot of POR total dissolved solids for the No. 1 Strip Pit is presented in Figure 11 and POR iron concentrations aze presented on Figure 12. Figure 11 indicates that the dissolved solids concentrations increased from an average of around 900 mg/l in the eazly 1980's, to about 1500 mg/1 in 1984 through 1986, and has stabilized to about 1,100 mg/l since 1987. Figure 12 illustrates the variable nature of total recoverable iron concentrations in the No. 1 Strip Pit discharge. During 2003, these levels remained within typical ranges seen for this site. 3.2.3 Ponds There was no dischazge from the sediment ponds in 2003. 4.0 SUMMARY AND CONCLUSIONS No significant, unpredicted, or adverse impacts were detected during hydrologic monitoring for 2003. Thus, under the temporary cessation monitoring plan, none of the seven events that might trigger reversion to the active mining plan occurred (see TROT-32, Appendix D, June 21, 2001). All monitoring requirements were 5 I:\Env\Empire\P,HR\2003\Text\E mpire2003AHR.doc