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to be monitored and discussed in the 2004 AHR. Note that initial water quality analyses in 2004 indicated lower <br />iron concentrations. <br />Recorded 2003 spoil spring discharges remain negligible and, therefore, did not constitute a significant portion of <br />discharge from the TCC mine area with the potential to impact off-site areas. Dischazges from sedimentation <br />ponds predominately occurred in conformance with applicable CDPS permit limitations and therefore did not <br />constitute significant impacts to receiving waters. Mine water discharge sites 109 (Table 64) and 115 (Table 65) <br />produced little water during the 2003 Water Year. <br />Historic sampling at site 1005 has shown that a sulfate level of 250 mg/1 correlates to a conductivity of <br />approximately 750 umhos/cm. In order to quantify the predicted effect of sulfate contributions from sites 115 and <br />109, TCC in association with a consultant, has developed a computer program -the "FCBH Calculator". In the <br />winter, when stream gauging is difficult, the FCBH Calculator uses the flow and conductivity values from sites <br />69 {Trout Creek above Fish Creek confluence) and 1005 (Trout Creek below Fish Creek confluence) to estimate <br />the appropriate discharge for sites 115 and/or 109. These same sites are also used to estimate appropriate flow for <br />site 109 in the summer. In the summer, the FCBH Calculator uses measured flow and conductivity values from <br />site 16A (upstream of discharge site 115), and conductivity values from site 115 to calculate how much mine <br />water, if any, may be discharged from site 115. TCC uses these methods to manage controllable discharge from <br />sites 115 and 109, and avoid contributing to sulfate exceedences downstream in Trout Creek. <br />Inflow: No unusual occurrences of inflow were noted as a result of the Annual Mine Inflow study. Inflows are <br />within the projected flows presented in the permit. Water quality has not changed significantly and appears to <br />minor the quality of the adjacent spoil water. It appears that the elevated EC and iron readings are associated <br />with the water that has pooled in [he mine sump, in contact with the overlying Marine Shale. This contact has <br />provided the opportunity for additional salts and iron to be leached from this unit. The pumping of the sump <br />should see a decrease in the elevation of the pool over time, with an anticipated decrease in the EC and <br />concentration of iron in the effluent. <br />Subsidence: During the first half of 2003, subsidence survey data was collected periodically from established <br />monuments on the Union Pacific Railroad and the YVEA power line in areas underlain by gate roads or panel <br />centers during periods of [Wining in the 14 Rt longwall panels. During the second half of 2003, subsidence survey <br />data was collected periodically from established monuments on the Union Pacific Railroad in areas underlain by <br />gate roads or panel centers during periods of mining in the 15-Right longwall panel. <br />No significant subsidence ponding, overlying subsurface mined areas along Foidel Creek or Middle Creek was <br />evident in 2003. Limited ponding was noted along a portion of Fish Creek (above Panel 14Rt) in 2003. The only <br />hydrologic anomalies noted were those associated with new surface sites SW-13 through SW-15, and their <br />associated Fish Creek alluvial wells, AVF-13 through AVF-15, as discussed above. <br /> <br />19 <br />