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1 <br />' stabilized since 1989. The data does not indicate any significant <br />' change in the trace metals concentrations although iron and <br />manganese concentrations are extremely variable. <br />Spoils <br />' Two wells in the Mine 3 spoils were installed in 1985 to monitor <br />water levels and water quality in mine spoils. The location of <br />these spoil wells is provided in Figure 2. One spoil well, <br />008-SP-4A has remained dry since it was installed. <br />Water Levels - The plot of the historic water levels in spoil well <br />008-SP-5A is presented on Figure 10. The water level has a similar <br />pattern to that of the alluvial wells, it rises during spring <br />runoff and then declines during the summer and fall. The general <br />trend in water levels in spoil well 008-SP-SA exhibits a relatively <br />slight decline similar to that of overburden well 008-70658. This <br />trend appears to represent a climatic influence suggesting that <br />water levels in the spoil have equilibrated and are not fluctuating <br />due to past mine disturbance. <br />Water Quality - The water quality data is summarized in Tables 12 <br />and 13 for the spoil well. The historic dissolved solids <br />concentrations for the well is plotted on Figure 11. The dissolved <br />solids average 3353 for the period of record. While highly <br />' variable, the dissolved solids concentration does not appear to be <br />increasing but in fact, shows a slight decrease in 1991.. The <br />water is a calcium-sulfate type with high bicarbonate and <br />relatively low SAR. The water is higher in dissolved solids than <br />' the background bedrock levels and the spoil spring discharges. The <br />data does not indicate any significantly high trace metals <br />concentrations except for relatively high dissolved manganese which <br />appears to have declined dramatically in 1991. Monitoring in <br />subsequent years will reveal whether this decline is persistent and <br />represents a geochemical change or flushing effect. At this point <br />in time, whether the decline in manganese is persistent and its <br />cause are not known <br />1 <br /> <br /> <br /> <br />' - 4 - <br /> <br />