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B. Excavating the sediment from the dewatered area of Robinson Lake will limit the amount of water <br />removed with the sediment. <br />3.2 Access Development at Excavation and Repository Locations <br />A. Access at the excavation and repository sites will be developed to ensure safe access by equipment. <br />Access locations into the sediment removal and repository areas will be as illustrated on Figures 2 <br />and 3. <br />3.3 Construct and Maintain Repository Site <br />A. The excavated sediment fill area will be accessed from the crest of 2 Dam. .The sediment repository <br />will be located in the Tenmile TSF on the south-east corner of Tenmile Tailing Pond, bounded by the <br />East Side Channel and the Tenmile water pool (Figure 3). <br />B. A repository for the sediment material will be constructed at the base of 2 Dam prior to placement of <br />material. This repository will be constructed in a manner to prevent sediment from potentially running <br />into the East Side Channel or the Tenmile water pool. In order to prevent sediment from running into <br />the Tenmile Pond pool and impacting water treatment operations, a containment berm will be <br />constructed of tailing sand adjacent to the East Side Channel and Tenmile pool. The containment <br />berm is estimated to be 3,000 feet Iong,10 feet high with a 12-foot wide top width to allow for access <br />to the perimeter for dust control activities. Actual field conditions may dictate that the containment <br />berm be adjusted to accommodate project requirements. <br />C. The face of 2 Dam will be maintained by pushing accumulated sediment down slope into the <br />repository area during operations. The existing cap material may be removed from the face of 2 Dam <br />in the dump area as necessary. <br />D. Water will be used for dust control of the repository area during operations. Water will be available <br />at the SDP and Lake Irwin for dust control operations. <br />3.4 Excavate and Haul Sediment <br />A. The Excavation Area is located at the upper end of Robinson Lake (Figures 1 and 2), above elevation <br />10,840 feet. The lime sediment volume in the Excavation Area is estimated to be up to a maximum <br />of approximately 450,000 cubic yards. Additional, native material may require excavation to provide <br />stable working areas for equipment. The additional native material to be removed is estimated to be <br />approximately 50,000 cubic yards. <br />B. A maximum of approximately 450,000 cubic yards of sediment will be removed from the Excavation <br />Area and hauled to the sediments storage area (adjacent to Tenmile Tailing Pond). Native soil <br />materials that can be separated easily at the Excavation Area will be hauled and stockpiled at the crest <br />of I Dam (approximately 1 mile, one-way) for later use in reclamation activities (Figure 1). <br />C. The haul route for the sediment will be from the Sediment Removal Area (Figures 1 and 2) along the <br />haul road to the north to the crest of 1 Dam, then across 1 Dam to the dump area at the crest of 2 <br />Dam. The haul route is approximately 2 miles, one-way. The alignment of the haul route is <br />illustrated on Figure 1. <br />3.5 Re-Grade 2 Dam Dump Area and Cover <br />A. Upon completion of sediment excavation activities, the face of 2 Dam will require re-grading to <br />approximate pre-existing slopes and covered to prevent erosion and dust generation. The cover will <br />