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slight increase in TDS concentrations at Foidel Creek alluvium appears at well 008-AV-. TCC will continue to monitor [he direction of this trend. No unusual observations are noted with respect to Fish Creek alluvium groundwater levels. The general water level decline noted in well 006-AY-1 (Figure 34) since 1995, appears to continue in 2005. Overall, fluctuations a[ [his well are insignificant. No other notable water level observations are apparent based upon review of the 2005 data. Field conductivity readings at this well appear stable over the last few years. Two new alluvia] wells (AVF-13 and AVF-14) were installed in August 2001, and one (AVF-15) in June 2002. The only unusual observation made to date were elevated iron concentrations in 2003 and 2004, some of which may be related to subsidence ponding, however, the data base for these sites will require expanding before a complete assessment can be made. Surface Water: Recorded surface water flows for Foidel Creek, Fish Creek, and Trout Creek were generally low in comparison to TCC's historic record. This.is undoubtedly associated with general drought conditions seen in this area over the last few years. Conductivity concentrations at site 301, 69, and 1005 on Trout Creek appeared elevated during the spring runoff season in late March and early April. This may be the result of upgradient spring runoff flushing through the old P & M mine area. No other notable water quality impacts are evident at any surface water sites monitored during 2005. • Recorded 2005 spoil spring discharges remain negligible and, therefore, did not constitute a significant portion of discharge from the TCC mine area with the potential to impact off-site areas. Discharges from sedimentation ponds predominately occurred in conformance with applicable CDPS permit limitations and therefore did not constitute significant impacts to receiving waters. Mine water discharge site 109 did not discharge to Foidel in 2005. Site 115 produced little water to Fish Creek during the 2005 Water Year. TCC has redirected mine water from this source, to underground locations for dust control. Historic sampling at site 1005 has shown that a sulfate level of 250 mg/1 correlates to a conductivity of approximately 750 umhos/cm. In order to quantify the predicted effect of sulfate contributions from sites I15 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) [o estimate [he appropriate discharge for sites 115 and/or 109. These same sites are also used to estimate appropriate flow for site 109 in the summer. In the summer, the FCBH Calculator uses measured flow and conductivity values from site 16A (upstream of discharge site 115), and conductivity values from site I15 to calculate how much mine water, if any, may be discharged from site 1]5. TCC uses these methods to manage controllable discharge from sites 115 and 109, and avoid contributing to sulfate exceedences downstream in Trout Creek. • In September 2005 site 1005 on Trout Creek exhibited a sulfate concentration of 360 mg/1. Note that TCC was not discharging to Fish Creek (via site 115) during this period. 15