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• minor or no flows only during the spring runoff. None of the stations at Mine 2 had significant flows in 1997. Most of the Eckman Park and Mine 1 ponds are in the Foidel Creek drainage, only Pond H (Site 57) is in the Middle Creek drainage. Pond M on Mine 2 is in the Fish Creek drainage. Pond D (Site 84) receives runoff from the waste rock disposal area as well as runoff from the surface mine. In addition, mine water from the Foidel Creek underground mine is also pumped to Pond D. Pond K (Site 41) drains to Foidel Creek and had no discharge during 1997. Flows The flow rate data for the effluent stations are summarized on Table 44. The historic discharge data for the ponds with significant 1997 water discharges at Mine 1 are presented in Figures 64 through 75. Discharges from these ponds are affected by seasonal variation in surface runoff and spoil spring flows. All of the plots show the typical seasonal variation with high flows during spring runoff. Historically, discharges from the ponds ceased in the summer and did not begin again until the next spring. Three ponds, A (Site 39), D (Site 84) and F (Site 87), began discharging year round in late 1984. This is due to the spoil springs located in the drainages of Ponds A, D, and F and the past underground mine discharge to Pond D. Due to utilization of Site 114 for water supplies by Twentymile Coal Company, Sites 114 and 87 experienced extended periods of no discharge during 1997. During the 1997 irrigation period, Pond A exhibited a mean flow of approximately 2.7 cfs, Pond D 0.9 cfs and Pond F 0.01 cfs. Pond F did not discharge significant amounts in the 1997 irrigation season, and has shown a decreased flow since 1991, due to periodic pumping of the • pond and Spring 114 for mine use. The discharge from Pond D was sustained throughout the year as shown on Figure 73. Flows from these ponds have changed Foidel Creek from an ephemeral to a perennial stream. Peak discharges from the ponds do not seem to have changed significantly because the spoil spring water would probably have discharged as snowmelt runoff anyway. Water Quality Summaries of the water quality data for the Mine 1 and Eckman Park ponds are presented on Tables 45 through 48. The water quality summary for Mine 2's Pond M is provided as Table 49. The field conductivity data shows some typical seasonal variation: the water quality improves during spring runoff. Ponds A, D, F, and H appear to be impacted by spoil spring inflows. The discharge rates from H are not significant during irrigation season and therefore do not cause any significant impacts. For the ponds affected by spoil springs, increased calcium, magnesium, sulfate, dissolved solids, and SAR are typically observed. No significant changes in parameters were observed for the ponds during the 1997. Conductivity and TDS levels observed on Trout Creek have recently been observed at levels lower than predicted by the CYCC PHC. The levels documented during 1997 at site 1005, the downstream monitoring site established for Permit No. C-82-056, were well below 2000 mg/I and therefore likely did not cause or have the potential to cause material damage. The water quality of Trout Creek was better than maximum levels predicted in the past salt-loading calculations performed as part of the "probably hydrologic impacts' section of the mine permit application with a maximum value of 620 mg/I recorded in August of 1997. Only insignificant discharges at Mine 2 were recorded • during spring runoff. Therefore, no impacts to Fish Creek were observed as a result of runoff from Mine No. 2 in 1997. EP97TEXT.DOC 07/01/98 9