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Alteration of surface flow patterns has resulted from construction of sediment ponds, ditches, diversions, <br />and the Refuse Pile. The Magpie Creek diversion, a permanent structure, existed prior to Southfield mining <br />operations. The much smaller diversion constructed up- gradient of the Refuse Pile is also a permanent <br />structure, as are the collection ditches around the refuse pile. All of the aforementioned structures were <br />approved for construction by the DRMS. Most of the surface flow patterns have been substantially <br />reestablished to pre- mining conditions during reclamation of the mine site. <br />The Permit discusses the potential for changes in surface water chemistry, including increases in levels of <br />TDS and specific chemical constituents, caused by operation of the sediment ponds. The two mine site <br />sediment ponds have not discharged since reclamation of the mine site completed in 2002, due in large part <br />to the successful establishment of vegetation on all of the reclaimed areas and ongoing maintenance of <br />drainage and sediment control structures. <br />Another predicted consequence is the potential for increases in sodium and sulfate concentrations in <br />Newlin and Magpie Creeks as a result of percolation through the Refuse Pile. No significant flows have <br />been monitored in Magpie Creek since the reclamation of the site, while there have been several low flow <br />events sampled in Newlin Creek from 2000 through present. A review of the surface water data in the <br />Annual Hydrology Reports indicates that sodium and sulfate values in Newlin Creek, sampled at the <br />downstream monitoring point, are not significantly different from sample data obtained at the upstream <br />monitoring point. In addition, no discernible trends in any other chemical constituents appear to be <br />occurring comparing the upstream and downstream monitoring data. <br />With regard to predicted surface water impacts, Boulay states in the above referenced Memorandum that <br />there is no evidence that the Southfield Mine has impacted the quality or quantity of water available as <br />streamflow in Newlin Creek. <br />Water Riaht Conseauences <br />Southfield's mining and related operations are not expected to impact any currently existing surface or <br />groundwater right according to determinations shown in the Permit. The recent review conducted by <br />Boulay and the DRMS supports this prediction. Boulay did not find any indication that wells within or <br />adjacent to the permit area have been impacted by the currently mining operation. <br />The owner of the Corley Company Well believes that the well was impacted by mining operations <br />because the well was undermined and has gone dry. EFCI contends that monitoring data indicate the well <br />went dry prior to mining operations being completed beneath the well. Nonetheless, EFCI is currently <br />mitigating the loss of use of this well by drilling a replacement well for the owner. <br />There is no evidence that downstream surface water rights have been impacted by the Southfield Mine. <br />Any mine related changes to flows in Newlin Creek could potentially impact downstream water users. <br />EFCI has determined that Newlin Creek is a losing stream system upstream of the Southfield Mine and <br />through the stretch of stream crossing the area affected by the mine. As mentioned above, Boulay and the <br />DRMS find no evidence that the Southfield Mine has impacted the quantity of water available as <br />streamflow in Newlin Creek. Their review supports this finding by stating that mining was conducted <br />adjacent to Newlin Creek from about 1900 through the 1970's making quantification of any impacts to <br />Newlin Creek from the Southfield Mining operation difficult to assess. More importantly, water flow in <br />4 <br />TR -43 Revised: 10/2014 <br />