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• Introduction <br />This appendix provides supplemental information to the Probable <br />Hydrologic Consequences discussion found in Section 2.5.3, Consequences of <br />Mining. Section 2.5.3 provides a discussion and prediction of the long- <br />term effects of all mining activities at the Edna Mine on Trout Creek <br />Total Dissolved Solids (TDS) concentrations. The discussion provided <br />herein provides an updated evaluation of the short-term effects of mining <br />activities on TDS levels in Trout Creek during the months of April through <br />October at the Edna Mine using data collected through October 1996. The <br />discussion is based on the TDS levels exhibited in Trout Creek from <br />immediately prior to the re-mining of West Ridge (1979) through completion <br />of mining and reclamation of West Ridge and the Moffat Area (1996). Data <br />supporting the analysis was collected for the mine's CDPS Permit and Annual <br />Hydrology Report, and is contained in the Table at the end of this <br />appendix. <br />Flow data used in this analysis included the upstream monitoring <br />station (TR-a), the CDPS effluent data from the mine's discharge points <br />• (002, 003, 009, 006 and 007) and the downstream monitoring site (TR-b). <br />CDPS discharge point 002 consists o£ the outfall of the West Ridge <br />sedimentation pond. CDPS discharge point 003 consists of the outfall of <br />the Center Ridge sedimentation pond. CDPS discharge point 009 consists of <br />the outfall of the Moffat sedimentation pond. All three of these discharge <br />points (002, 003 and 009) capture flow from upland spoil springs. As such, <br />the flow and TDS values from these points reflect all the spoil spring <br />water discharged from the mine to Trout Creek from areas affected under the <br />permanent regulatory program, except for one. CDPS discharge point 006 <br />consists of discharge from a spoil spring located at the base of the West <br />Ridge mining area which does not pass through any sedimentation structure. <br />Monitoring of this spring, which corresponds to spring C3 from previous <br />baseline studies, resumed in 1986. CDPS discharge point 007 consists of <br />the combination of discharge points 002, 003 and 006. Discharge point 007 <br />was established in June 1996 below the confluence of the discharge points <br />previously mentioned to more accurately reflect the manner in which <br />discharge from the mine leaves the permit area. <br />Streamflow data on Trout Creek for the years 1989 and 1965 were not <br />available for this analysis because an early rapid snowmelt in 1989 caused <br />flooding conditions which destroyed both the upstream (TR-a) and downstream <br />• (TR-b) continuous flow monitoring stations. TR-a was re-established in <br />Renewal 3 2.6A-1 June 13,1997 <br />