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• of the mine discharge points. Under TC, Williams Fork surface sampling (site WF-1) is measured for water <br />level and field parameters on an annual basis (between July ZOth and August 30th), and requires water quality <br />analysis (See Table 3). WF-2 is also monitored concurrent with WF-1. <br />The flow data for WF-2 was historically provided by the USGS, however, monitoring of the Williams Fork <br />stations was discontinued in 2001. Historically, comparisons between up gradient site WF-1, and down <br />gradient site WF-2, have no[ show any stream depletion impacts from mine dewatering. <br />Summaries of WF-1 and WF-2 water quality data are presented in Tables 13 through 16. A plot of upstream <br />and downstream dissolved solids measurements for the river is presented in Figure 8. The data indicates that <br />the surface water quality does not show any significant variation from expected values. The comparisons of <br />data from the upstream and downstream station on the Williams Fork River indicate that there is no detectable <br />effect of mining on river water quality. As expected, dissolved solids decrease with increasing flow rate in <br />the rivers, due to dilution from runoff. <br />3.2.2 Springs <br />One spring on the mine site area is being monitored under TC, the No. 1 Strip Pit Discharge. The No. 1 Strip <br />Pit Discharge is a CDPS monitoring point (Outfall 022, a.k.a. site ISP). There are a few other springs and <br />local permanent "damp spots" in the azea; however, their combined Flow is normally less than 10 gpm and is <br />• therefore not significant. The POR discharges for the No. 1 Strip Pit are presented in Figure 9 and the 2004 <br />discharge measurements are presented on Figure 1Q, respectively. The discharge from the No. 1 Strip Pit <br />increased significantly back in 1989. This may have been due to seepage from the ditch that conveys the 7 <br />North Angle discharge. The 7 North Angle discharge began in January of 1989. However, discharge rates <br />from 1990 through 2004 appear lower. Nevertheless, snowmelt and ditch seepage both appear to have some <br />influence on the No. 1 Strip Pit discharge, as the discharge typically drops to just a few gpm from January <br />through May with a small peak typically in March coinciding with spring mnoff. <br />The summary of the water quality data for the spring is presented in Tables 17 and I8. A plot of POR total <br />dissolved solids for the No. 1 Strip Pit is presented in Figure 11 and POR iron concentrations are presented <br />on Figure 12. Figure 11 indicates that the total dissolved solids (TDS) concentrations increased from an <br />average of around 900 mg/1 in the early 1980's, to about 1500 mg/1 in 1984 through 1986, stabilized to about <br />1,100 mg/l between 1987 and 2003. In 2004 TDS concentrations averaged 1200 mg/I. Figure 12 illustrates <br />the variable nature of total recoverable iron concentrations in the No. 1 Strip Pit discharge. During 2004, <br />these levels remained within typical ranges seen for this site. <br />3.2.3 Ponds <br />With the exception of Outfall 003 (discussed under section 3.1.2), there was no discharge from the sediment <br />• ponds in 2004. <br />5 <br />I;\Env\EmpireW HR\2004\Text\Empire2004AHR.tloc <br />