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1 <br /> <br /> <br /> <br />1 <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br />1 <br />measurements for the river is presented in Figure 25. The data indicates <br />that the surface water quality does not show any significant variation <br />from expected values. The data from the upstream and downstream station <br />on the Williams Fork River indicate that there is no detectable effect of <br />mining on river water quality. As expected, conductivity decreases with <br />increasing flow rate in the rivers. This is due to the effects of snow <br />melt and high rainfall diluting the water. <br />SPRINGS <br />Spring Flow <br />Three springs on the mine site area are being monitored: These springs <br />are the No. 1 Strip Pit Discharge, Haxton Spring, and the North Spring. <br />The No. 1 Strip Pit Discharge is a NPDES monitoring point. There are a <br />few other springs and local permanent "damp spots" in the area; however, <br />their combined flow, is less than 10 gpm and are therefore not <br />significant. The measured discharges for the No. 1 Strip Pit are <br />presented in Figure 26 and the discharges for the other two springs are <br />presented in Table 32 and Figure 27. All of the discharges show a normal <br />seasonal runoff period and low flows in the winter and early spring; with <br />some spring flows being so low that they become too low to measure, inpart <br />due to freezing. <br />The average discharge from the <br />flows at the Haxton Spring way <br />from the North Spring was 7.7 <br />1987 than in previous years <br />discharge from the No. 1 Strip <br />Figure 26). <br />No. 1 Strip Pit was 7.5 gpm. Measurable <br />not observed in 1987. The average flow <br />gpm. Average spring flows were lower in <br />due to the lower runoff. The average <br />Pit has steadily declined since 1982 (see <br />Water Quality <br />Summaries of the water quality data for the springs is presented in Tables <br />33 through 36. Due to insufficient flow, no samples were collected from <br />Haxton Spring in 1987. No significant changes in the natural springs <br />water quality are evident (See Figure 28). A plot of dissolved solids for <br />the No. 1 Strip Pit is presented in Figure 29. It indicates that the <br />dissolved solids level of the discharge has increased from an average of <br />approximately 900 mg/1 in 1982 and 1983 to almost 1,400 mg/1 in 1986 and <br />then decreased to 1,150 mg/1 in 1987. As the dissolved solids increased <br />the flow rate has decreased, therefore the total salt loading has not <br />significantly changed. Also, this trend of increasing dissolved solids <br />appears to have leveled off. No other significant change in water quality <br />was observed. One violation of the NPDES permit for the No. 1 Strip Pit <br />Discharge was detected in 1987. The suspended solids was measured at 74 <br />mg/1 on June 19, 1987. This exceeds the maximum daily standard of 70 <br />mg/1. <br />1 <br />