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damage from the PMF; however, the inlets would most likely require cleaning. The exception <br />to this is the Ute Creek Reservoir bypass intake. Significant effort would be required to repair <br />this inlet if it assumed that Ute Creek Dam will fail during the flood, as the flood routing <br />analysis indicates. <br />The existing interceptor canal around the tailing basin does not include overflow <br />spillways at the several small tributary crossings. It is likely that during the PMF the canal <br />would wash out at the crossings and would require repair. It is anticipated that this repair <br />would be a high priority in the days following the PMF. This repair could be accomplished <br />using equipment and personnel at the mill and /or outside contractor equipment and labor. It <br />is expected that overtopping outside of the tributary crossings would be fairly well diffused <br />because of the very flat grade of the canal and access road (0.1 foot of fall in 100 feet). <br />Floodwater flow with the highest erosion potential would be focused on the crossings. Other <br />excess water would overtop with modest erosive energy. If the canal were damaged by the <br />flood, it is expected that this damage would occur at isolated areas that could be quickly <br />repaired. <br />For the purposes of this analysis, it is assumed that it would take approximately 7 <br />days after the flood to repair the East Branch and Horseshoe intakes so that this flow would <br />be diverted into the flood bypass pipeline and out of the system. With respect to the lower <br />flood bypass canal, we estimate that it would require approximately two weeks of earthwork <br />effort to repair the canal. These assumptions are necessary to determine the post -flood <br />adjustment described below. <br />Methods of Floodwater Removal <br />Due to the elimination of the gravity flow decant/spillway system, the plan for removal <br />of the floodwaters from the tailing pond must involve pumping. The pumping options that <br />would be available at the mill would include the proposed pump barge, the use of `on- site" <br />portable diesel pumps, and the use of imported diesel pumps. <br />• Pump Barge: It is unlikely that the proposed barge pumping system would be <br />significantly damaged during the PMF event. The discharge pipeline is buried with a <br />minimum of five feet of cover and power is supplied via an overhead power <br />15 <br />