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• Monitoring was initiated at Middle Creek alluvial well AVM-1 during 1996. During 2001, no unusual observations are noted with respect to the Middle Creek alluvium groundwater levels. No unusual observations ace noted with water quality characteristics comparable to other alluvial wells in the area. Recorded surface water flows for Foidel Creek, Fish Creek, and Trout Creek (Table 56) were compazable to TCC's period of record data. TDS concentrations at site 1005 (Table 53) on Trout Creek, downstream of all mining operations, peaked at 490 mgll in Mazch TDS concentrations at site 800 (Table 39) on Foidel Creek, upstream of the mine facilities, peaked at 3500 mg/l in August. TDS concentrations at site 8 (Table 40) on Foidel Creek, downstream of the mine facilities, peaked at 3700 mg/1 in August. No other notable water quality impacts aze evident at arty surface water sites monitored during 2001. Recorded 2001 spoil spring dischazges remain negligible and, therefore, did not constitute a significant portion of dischazge from the TCC mine azea with the potential to impact off-site areas. Dischazges from sedimentation ponds predominately occurred in conformance with applicable CDPS permit limitations and therefore did not constitute signiScant impacts to receiving waters. Mine water dischazge sites 109 (Table 64) and 115 (Table 65) produced little water during the 2001 Water Year. When pumping mine water from the Fish Creek Borehole (mine dischazge site 115) the flow becomes a contributor to sulfate levels in Fish Creek. When pumping mine water from the EMD Dewatering Well (mine dischazge site 109) the flow bewmes a wntributor to sulfate levels in Foidel Creek. Fish Creek and Foidel Creek, in turn, contribute to the sulfate levels in Trout Creek. Trout Creek currently has a secondary drinking water standazd limiting sulfate to 250 mg/l. Historic sampling at site 1005 has shown that a sulfate level of 250 mgA correlates to a conductivity of approximately 750 umhos/cm. In order to quantify the predicted effect of sulfate contributions from sites 115 and 109, TCC in association with a consultant, has developed a computer program -the "FCBH Calculator". In the winter, when stream gauging is difficult, the FCBH Calculator uses the flow and conductivity values from sites 69 (Trout Creek above Fish Creek confluence) and 1005 (Trout Creek below Fish Creek confluence) to estimate the appropriate discharge for sites 115 andJor 109. These same sites are also used to estimate appropriate flow for site 109 in the summer. In the sttmmer, the FCBH Calculator uses measteed flow and conductivity values from site 16A (upstream of discharge site 155), and conductivity values from site 115 to calculate how much mine water, if any, may be discharged from site 115. TCC uses these ,methods to manage controllable dischazge from sites 115 and 109, and avoid contributing to sulfate exceodences in Trout Creek. No unusual occurrences of inflow wore noted as a result of the 2001 Annual Mine Lrflow shrdy. Inflows are within the projected flows preserded in the permit. Water quality has not ganged sigrtific8ntly and appears to mirror the qualify of the adjacent spoil water. It appears that the elevated EC and iron readings are associated with the water that has pooled in the mine sump, and this water has been in contact with the overlyirg Marine Shale. This cotl~ct has provided the opportunity for additional salts and iron to be leached from this unit. The pumping of the sump should see a decrease in the elevation of the pool over time, with an anticipated decrease in the EC and concertlration of iron in the effluent. 17