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PERMIT#: M-1985-029 <br /> INSPECTOR'S INITIALS: MAC <br /> INSPECTION DATE: October 3,2014 <br /> At the conclusion of the inspection, the Division had determined that any discharge of sediment into the <br /> Middle Fork of the South Platte River did not occur as a result of a surface breach at the mine site. In addition, <br /> the amount of sediment observed in the river and the speed with which it appeared indicated the sediment <br /> was not being conveyed through the alluvium, but rather had been directly conveyed into the river. The only <br /> potential source of sediment which was identified during the inspection was the intake pipe near the pump <br /> house. The Operator committed to not operating the trommel or discharging wash water into the settling <br /> ponds until such time as the source of sediment was identified. In addition, the Operator committed to <br /> locating the check valve in order to determine if it had failed. <br /> Following the inspection, the Division contacted Mr. Murray via telephone and requested that all mining <br /> operations cease until the source of the sediment was identified. In addition, the Division requested that High <br /> Mountain Mining Company provide a plan for identifying the source of the sediment discharge as well as <br /> measures taken to prevent any future discharge of sediment. Mr. Murray agreed to comply with the Division's <br /> request. On October 4, 2014, Mr. Murray notified the Division via telephone that the source of the sediment <br /> discharge had been identified. Mr. Murray informed the Division the water line from the alternate diversion <br /> point did not have a check valve to prevent back-flow. In addition, it was determined the valve on the <br /> freshwater line was left in the wrong position at the end of the work shift on October 2, 2014. The valve is <br /> normally left in the position which directs water to the processing building; however, the valve was set to <br /> direct water to Pond 4. The pump was turned off at approximately 9:00pm on October 2, 2014. As noted <br /> above, the level of the discharge pipe into Pond 4 was located below the water surface level. When the pump <br /> was turned off, the water from Pond 4 back-flowed into the river through the intake pipe. The discharge of <br /> sediment laden water continued until the next morning when the pump was turned back on. The Alma Placer <br /> Mine does not use chemicals in the processing plant; the water which entered the river contained silts and <br /> clays which had been washed from the placer deposits. <br /> On October 5, 2014, High Mountain Mining Company provided the Division with a plan to prevent future <br /> discharges of sediment into the Middle Fork of the South Platte River. The Operator committed to taking the <br /> following actions: <br /> 1. The fresh water discharge pipe to Pond 4 will be raised to an elevation above that of the overflow pipe. <br /> 2. A check valve will be installed on the end of the fresh water pipe and will be located above ground. <br /> 3. A sign will be installed at the valve which directs water to either Pond 4 or the processing building. <br /> 4. Employees will be re-trained on the correct operation of pond systems and valves. <br /> 5. Sediment from Ponds 3 and 4 would be cleaned out as planned. <br /> General Compliance with Mine Plan: <br /> The Division reviewed the Mining Plan which was most recently updated through Amendment No. 4 in 2004. <br /> The Mining Plan states wash water from the processing plant will discharge into four ponds (Farley Pond 1-4) <br /> before the water enters a collection ditch and then flows into Pond A (referred to as Pond 4 throughout this <br /> report). Based on a review of an aerial photograph of the site and observations made during the inspection, <br /> the Division has determined the Operator has deviated from the approved sediment collection plan. Currently, <br /> the water from the processing plant flows through two upper ponds before flowing into a collection ditch <br /> which then flows into two lower ponds. In addition, Exhibit C-4: Hydrology Map depicts the fresh water line <br /> running from the pump house directly to the processing plant. The map does not depict the fresh water line <br /> running to Pond 4 and the Mine Plan does not state that Pond 4 would be filled by the fresh water line. <br /> Page 4 of 11 <br />