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' For the Williams Fork River, the maximum mean daily flow was 914 <br /> cfs, the minimum mean daily flow was 15 cfs, and the mean flow was <br /> ' 134 cfs. A plot of minimum mean monthly and maximum mean monthly <br /> flows, measured by the USGS for the Williams Fork River at Cyprus <br /> Empire Corporation, is presented in Figure 26. The flows in the <br /> Williams Fork River were below normal in 1989 . These flows, <br /> ' measured to date by Cyprus Empire Corporation, do not show any <br /> significant variation from expected values. <br /> ' WATER QUALITY <br /> Summaries of the water quality data are presented in Tables 29 <br /> ' through 32 . A plot of upstream and downstream field electrical <br /> conductivity measurements for the river is presented in Figure 27 . <br /> The data indicates that the surface water quality does not show any <br /> ' significant variation from expected values. The data from the <br /> upstream and downstream station on the Williams Fork River indicate <br /> that there is little to no detectable effect of mining on river <br /> ' water quality. As expected, conductivity decreases with increasing <br /> flow rate in the rivers. This is due to the effects of snow melt <br /> and high rainfall diluting the water. <br /> ' SPRINGS <br /> FLOWS <br /> One spring on the mine site area is being monitored. The spring <br /> ' is the #1 Strip Pit Discharge. The #1 Strip Pit Discharge is a <br /> NPDES monitoring point. There are a few other springs and local <br /> permanent "damp spots" in the area; however, their combined flow <br /> is normally less than 10 gpm and are, therefore, not significant. <br /> ' The measured discharges for the #1 Strip Pit are presented in <br /> Figure 28 . The discharges show a normal seasonal runoff period, <br /> with low flows in the winter and early spring. Most of the flows <br /> were so low, in part due to freezing, that they become too low to <br /> measure. <br /> The average discharge from the #1 Strip Pit in 1989 was 72 gpm. <br /> ' The discharge from the #1 Strip Pit increased significantly in <br /> 1989. This is probably due to seepage from the ditch that conveys <br /> the 7 North Angle discharge. The 7 North Angle discharge began in <br /> ' January of 1989 . Also, the data for the period from February 21, <br /> 1989 to May 9, 1989 is estimated, due to problems with the flow <br /> measurement device. <br /> ' WATER QUALITY <br /> ' The summary of the water quality data for the spring is presented <br /> in Tables 33 and 34 . A plot of dissolved solids for the #1 Strip <br /> Pit is presented in Figure 29. It indicates that the dissolved <br /> ' solids level of the discharge has increased from an average of <br /> ' -4- <br />