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23. Period of record field conductivity data for sites 700, 29, and 900 is presented as Figures 24, 25, and <br />• 26 respectively. 1994 Water Year field conductivity data is plotted collectively for all three sites and <br />presented as Figure 27. <br />The historic base level field conductivity on Foidel Creek (Site 900, Figure 26) measured during spring <br />runoff, averages approximately 1000 umhos/cm. Since 1981 the typical level has steadily increased and this <br />trend appears to continue with 1994 values ranging between approximately 2000 and 3700 umhos/cm. This <br />increasing general trend is attributable to the effects of other mine discharges upstream of Mine No. 3. The <br />irrigation season field conductivity levels at Site 900 exceeded 3000 umhoslcm during August and September <br />of 1994. A similar trend is apparent at Site 29 (Figure 25) although slightly lower field conductivity values <br />are typical at this location presumably due to the dilution attributable to Middle Creek above the confluence <br />of Middle and Foidel Creeks. Period of record field conductivity data for Site 700 (see Figure 24) continues <br />to vary within established ranges with no readily observable trend apparent. Field conductivity values at <br />this site are markedly lower than those encountered at Sites 29 and 900. <br />All other monitored water quality parameters for surface water sites 700, 900, and 29 are observed to fall <br />within previously established ranges far the 1994 Water Year with the exception of uncharacteristically low <br />pH values being measured in August 700 and 900. A corresponding low value was ttot noted at Site 29 <br />during the same period. Subseyuent to the low values being recorded, pH levels returned to more typical <br />• ranges. Total suspended solids concentrations remained typically low throughout the 1994 Water Year with <br />a seasonal elevation presumably attributable to spring runoff recorded at Site 700. <br />SPOiL SPRING MONITORING <br />The spoil spring monitoring program was initiated in 1986 and is conducted annually. In accordance with <br />the approved plan, the annual mine wide survey is conducted during May with springs measured for flow <br />and field parameters. If a spring is discharging at or above 35 gallons per minute it is monitored throughout <br />the remainder of the year in accordance with the monitoring plan. During the 1994 Water Year monitoring <br />effort, no spoil springs were observed producing flow sufficient to require additional sampling (se Table 17). <br />No measurable flows were encountered, several sites were completely dry, and the remaining sites were <br />noted as seeps or trickles. Field conductivity values obtained from the sites with moisture apparent were <br />relatively Higher than values recorded itt 1993. <br />EFFLUENT MONTI'ORING <br />Two sediment ponds (Pond M3N -Site 24; Pond M3S -Site 76) are monitored as part of the Mine 3 <br />• approved program. Pond M3N (Site 24) is located at the reclaimed area immediately north of the confluence <br />of Foidel Creek and Middle Creek to control runoff from reclaimed areas of the abandoned Middle Creek <br />-6- <br />