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<br />Statamant of Position <br />Paga 2 <br />make-up to the process water tank continues) since the <br />fresh water feed pumps are not shut down. Overflow of <br />the process water tank into the reclaim overflow line <br />begins. <br />3) While attempting to move the reclaim overflow rain line, <br />the line is flexed damaging both the inner pie coupling <br />and outer pipe coupling. Leakage begins to occur. <br />Approximately 5-7 minutes after being observed, the fresh <br />water feed pump to the process water tank islshut down. <br />Overflow continues 2-3 minutes. <br />4) A total of approximately 10,000 gallons m ximum has <br />escaped the pipe of which approximately 1500 allons has <br />drained into a drainage ditch sump at the a ge of the <br />tailings pond but within tertiary containm nt. The <br />remaining 8500 gallons flows onto the clay li er in the <br />tailings pond construction area but within secondary <br />containment. <br />5) Remedial pumping to primary containment and r placement <br />of saturated clay liner is immediately initia ed. <br />6) Fluid samples and soil samples are retrieved, reserved, <br />and sent for outside analysis (WAD and total c anide) at <br />Core Laboratories. The Division was provid a fluid <br />sample for comparative analysis. <br />7) Fluid sample results are received indicating .16 ppm <br />total cyanide and .16 ppm WAD cyanide (these alues are <br />below the federal drinking and groundwater advisory <br />limits). Soil sample results indicate non-detestable for <br />both WAD and total cyanide. <br />The Division was on-site conducting a tailings facility <br />construction inspection when the event occurred and (therefore <br />witnessed items 3 through 6. As previously mentioned a fluid <br />sample was provided to the Division for separate analysis. <br />There exist several key issues to this incident tha~ require <br />detailing. First, it is important to note that the fluid released <br />and verified by independent sampling did not at any time represent <br />a risk to human health or the environment. This was d e to two <br />factors: The cyanide level in the tailings facility w ter pool <br />that is brought into the process water tank is extrem ly low - <br />generally less than 2 ppm WAD cyanide and second, the reclaim water <br />is normally mixed with fresh water in the process water to k (fresh <br />water from the farm well system approximately 6 miles nor h of the <br />mine site). Second, all the pipelines previously identified are <br />not normally relocated or moved except during this lane time <br />construction sequence. This being the case, random pipeline <br />flexure that results in a joint or coupling failure is xtremely <br />remote. (i.e., this was an extremely unusual event to move the <br />pipeline and pipeline failure resulted due to the added eight of <br />