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Longfellow Koehler Project <br /> Page 3 <br /> Infiltration Controls (,contj <br /> (1) Thorough examination of the surface looking for features which may be diverting <br /> water through mine workings. <br /> (2) Should any features be found they will be studied to see if Best Management Practice <br /> run on run off controls have the potential to reduce the volume of water flowing into <br /> and through the mine workings. <br /> (3) SGC will implement controls such as ditching, to prevent infiltration where <br /> practicable. <br /> Site Run On Controls <br /> There exist two possible sites for run on controls at the portal area. The first source of water <br /> flows from the drainage area and pond to the North,around the Longfellow Shaft and contacts dump <br /> material before flowing into the lower pond at the portal area. The second source of flowing water <br /> needs to be evaluated but may be flowing from U.S. Basin. This stream flows next to the South <br /> (Koehler) Adit and contacts the dump material. Both sources can be best handled by simple <br /> diversion in a lined ditch to prevent any contact with contaminated water or mine waste material. <br /> The ditch water will be recombined below the site named M-02. <br /> Mine Waste Remediation <br /> The waste dumps will be moved and isolated from portal flows, intermittent flows and the <br /> pond. SGC will move and consolidate the dumps and adjust their pH to near neutral, by addition <br /> of lime, limestone or another acceptable product, for stabilization. <br /> Preferably an isolation site can be found onsite. As an alternative, the dumps will be <br /> relocated to SGC's Tailings Pond#4. Prior to consolidation either onsite or offsite,the pH will be <br /> adjusted to near neutral. Once removal and consolidation is completed, the material will be capped <br /> with 14-16" of soil,provided that amount of soil is available, and planted in order to prevent direct <br /> contact with water. <br /> Surface disturbances will be pH adjusted with the use of limestone addition and planted. <br /> SGC will apply for a general or individual 404 permit from the Army Corps of Engineers for the <br /> work in the stream. <br /> Removal of buildings will be required on the South (Koehler) dump. This will require <br /> working with the San Juan County Historical Society and the San Juan County Commissioners. <br /> Planned activities would include historical recordation prior to removal. It is intended to leave all <br />