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SPOIL SPRING MONTI'ORiNG The spoil spring monitoring program was initiated in 1986 and is conducted annually. in accordance with the approved plan, the annual mine wide survey is conducted during May with springs measured for flow and field parameters. If a spring is discharging at or above 35 gallons per minute it is monitored throughout the remainder of the year in accordance with the monitoring plan. During the 1996 Water Year monitoring effort, no spoil springs were observed producing flows sufficient to require additional sampling (see Table 17). NPDES DISCHARGE MONITORING Two sediment ponds (Pond M3N -Site 24; Pond M3S -Site 76) are monitored as part of the Mine 3 approved program. Pond M3N (Site 24) is located at the reclaimed area immediately north of the confluence of Foidel Creek and Middle Creek to control runoff from reclaimed areas of the abandoned Middle Creek underground mine. Pond M3N (Site 24) is subject [o the effluent limitations detailed in NPDES Permit No. COG-850013. Pond M3S (Site 76) is located south of the confluence and east of Middle Creek to control runoff from reclaimed • areas east of Middle Creek. Pond M3S (Site 76) is subject to the effluent limitations detailed in NPDES Permit No. CO-0027154. Sites 24 and 76 (See Tables 14, 14A, 14B, 15 , ISA, and ISB) discharged only in response to spring runoff during the 1996 Water Year. Discharges occurred in conformance with the established NPDE5 effluent limitations. Figures 26 and 27 provide graphical representations of the field conductivity values measured for these sites during the 1996 Water Year. With the exception of the initial field conductivity value recorded for site 76 in April, all values were within the expected range of readings previously experienced. The initial reading was likely influenced by snowmelt runoff. The initial sample measurements were obtained from the end of the discharge pipe which is situated in the stream channel and typically is submerged. Subsequent samples were drawn from the stand pipe attached to the discharge conduit prior to the outfall point. CONCLUSIONS No significant hydrology impacts attributable to activities or developments at Mine No. 3 are observed to have occurred during the 1996 Water Yeaz. Spoil spring discharges remained negligible and, therefore, did not constitute a significant portion of discharge from the Mine No. 3 area with arty potential to impact off=site areas. . The previously discussed trends of elevating field conductivity measurements and TDS concentrations in the -7-