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' flows for the Williams Fork at Hamilton (a discontinued USGS gaging station). The maximum mean daily flow was 398C cfs and the maximum instantaneous flew was 4750 cfs. The minimum mean daily flow was 55 cfs ' and the minimum instantaneous flow was 45 cfs. The flows in the Williams Fork and Yampa Rivers measured to date by Empire ' Energy do not show any significant variation from expected values. River Water Quality ~ Surtmaries of the water quality data are presented on Table 22 to Table 29. Plots of upstream and downstream field elec*_rical conductivity and ' suspended solids measurements for each river are presented on Figure 24 to Figure 27. The data indicates that the surface water quality does not show any significant variation from expected values. The 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, conductivity decreases and suspended solids increase with increasing flow rate in the rivers. This is due to the effects of snow melt and high rainfall diluting the water and increasing erosion. SPRINGS Spring Flow ^ Four sprinds in the mine site area are being monitored. These springs are the No. 1 Strip Pit discharge, North Spring, Lippard Spring No. II and the Haxton Spring. The No. 1 Strip. Pit discharge is a NPDES monitoring point. There are a few other springs and local permanent "damp spots" in the area; however, their combined flow is less than ten gpm and are therefore not significant. The 1984 measured discharges for the No. 1 Strip Pit are presented on Figure 28 and the discharges for the rest of the springs are presented on Table 30. All of the discharges show a ' normal seasonal variation in flow. The high flows occurring during the snow-melt runoff period and low flows in the winter and early spring with some spring flows being so low that they become too low to measure, inpart due to freezing. The 1984 flows from the springs show a little higher ' values then previously recorded due to the higher snowfall/runoff in 1984. The average discharge from the No. 1 Strip Pit was 32 gpm. The average discharges from the other springs are shown on Table 30. Measurable flow was' never observed at the Haxton Spring and sufficient flow to collect a sample was only observed once. In addition, the average flow from the ' North Spring was 18 gpm the average flow from Lippard Spring No. II was 42 gpm. The measured flow for Lippard Spring yo. II includes some surface runoff. -5-