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C. The face of 2 Dam will be maintained by pushing accumulated sediment down slope into the <br />deposition area during operations. The existing cover material may be removed from the face of 2 <br />Dam as necessary. <br />D. Water will be used for dust control of the deposition 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 lower end of Robinson Lake as shown on Figure 1. The lime <br />sediment volume in the Excavation Area is estimated to be approximately 800,000 cubic yards. <br />Additional, native material may require excavation to provide stable working areas for equipment. <br />The native material to be removed is estimated to be approximately 200,000 cubic yards. <br />B. Approximately 800,000 cubic yards of sediment will be removed from the Excavation Area and <br />hauled to the sediment deposition area. Native soil materials that can be separated easily at the <br />Excavation Area will be hauled and spread on the face of l Dam or stockpiled for later use in <br />reclamation activities (Figure 1). <br />C. Climax performed sampling and analysis of the native materials removed for metals and agronomic <br />properties in 2008. Native materials salvaged during the 2010 effort will also be sampled and <br />analyzed for agronomic properties. The results of the 2008 analyses of agronomic properties are <br />provided in Table 1. If any soil remains in stockpile past December 2010, Climax will apply the <br />approved seed mix to the stockpile in the spring of 2011. <br />D. The haul route for the sediment will be from the Sediment Removal Area along the haul road to the <br />north to the crest of 1 Dam, then across 1 Dam to the dump area at the crest of 2 Dam. The haul route <br />is approximately 2 miles, one-way. The alignment of the haul route is illustrated on Figure 1. <br />E. Water will be used for dust control along the haul routes during hauling operations. Water will be <br />available at Lake Irwin and Chalk Mountain Reservoir for dust control operations. <br />3.5 Protection of Robinson Lake Dam <br />A. Climax will work with the Colorado State Engineer's (SEO) Dam Safety Engineers to determine <br />what, if any restrictions will be required for removal of materials up to the inside toe of the dam. The <br />dam inspector stated, during his inspection on June 16, 2010, that no notification or involvement from <br />the SEO's office would be required as long as there was no excavation within 200 feet of the <br />upstream toe of the dam. If Climax intends to excavate materials closer than 200 feet from the toe of <br />the dam, the SEO will require a review of the geotechnical information available and possibly <br />additional geotechnical investigation and inspection of the area to determine if there will be any <br />effects to the structure. <br />3.6 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 />smooth slopes and covered to prevent erosion and dust. This cover will be approximately 18 inches <br />of clean fill, suitable for reclamation, placed on disturbed slope areas. To the extent possible, the <br />removed cap material will be salvaged and used to cover the disturbed area. If additional material is <br />required, clean fill material from beneath the sediments in the Robinson Lake is expected to meet the <br />criteria for covering areas disturbed by sediment storage operations and will be used as needed. <br />B. Revegetation of covered areas will be accomplished by hydroseeding using the approved Climax seed <br />mix and seeding rates. Seed, fertilizer and mulch may be applied to areas disturbed by the sediment