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17. Lafarge intends to install a conveyor structure from the Duckworth Pit to the Cottonwood Pit. <br />Please provide additional information regarding the conveyor structure (i.e. composition, <br />length, width, height, foundations, etc.) and a specific plan for reclamation of the conveyor <br />structure. <br />Rule 6.4.5 Exhibit E- Reclamation Plan <br />18. Please explain how the backfilled overburden and topsoil material will be placed in the pit to <br />ensure stable slopes. In particular, please explain how lifts will be placed and compacted to <br />ensure the material is in a stable configuration. <br />19. On page 10 of 45 of the application and on the "Reclamation Specifications" noted on <br />Exhibit F, Lafarge states that slopes within 5 feet above to 10 feet below the post-mine water <br />table will be no steeper than 3h:ly. Please state to what grade the remaining slopes will be <br />beyond 10 feet of the post-mine water table (see Rule 3.1.5(7) for grading requirements). <br />20. Lafazge proposes to replace 3" to 6" of topsoil on the reclaimed azeas. The Duckworth site <br />contain two soil units consisting of Unit 4 (Aquolls and Aquepts, flooded) and Unit 10 <br />(Bankazd Sandy Loam). The Aquolls and Aquepts soils aze located west of Idaho Creek and <br />aze generally of poor quality. The Bankard Sandy Loam is located east of Idaho Creek. The <br />Bankazd Sandy Loam will be a more suitable soil for reclamation, and should be completely <br />salvaged for topsoil replacement. Because two large ponds will be created on site, enough <br />topsoil should be available for a replacement depth of 6" to 12." Please commit to salvaging <br />all of the Bankazd Sandy Loam in stockpiles and replacing to a depth of 6" to 12" at the <br />entire Duckworth site. <br />21. Lafazge proposed anon-native seed mixture in the reclamation plan. Because a portion of <br />the site is slated for wildlife habitat, Lafarge should propose a native seed mixture. The <br />Division recommends that you contact the Division of Wildlife (DOW) or the Soil <br />Conservation Service (SCS) for a seed mixture more conductive for a postmining land use of <br />wildlife habitat. (When proposing a new seedmixture, please specify a rate that falls within <br />40 seeds/sq.ft. for drilling and 80 seeds/sq.ft. for hydro-seeding or broadcast seeding). <br />22. Lafazge states that in areas that aze peripheral to the post-mining lake, mazsh and aquatic <br />plants will establish themselves. Lafazge should commit to planting various trees and shrubs <br />rather than relying on natural reintroduction. Please specify the type of trees, shrubs to be <br />planted and the quantity, size and location that would facilitate the reclamation plan. <br />23. A number of culverts aze depicted on Exhibit F. Please explain the culverts that Lafarge <br />intends to construct to facilitate the mining and reclamation plan and provide the appropriate <br />designs. <br />24. Lafarge does not state if the azea will be mulched. However, the reclamation cost estimate <br />prepazed by Lafazge includes 4000#/acre of grass hay or straw. Please clarify this <br />discrepancy. <br />Rule 6.4.7 Exhibit G- Water Information <br />25. Please provide an estimate of the project water requirements including flow rates and annual <br />volumes from the development, mining and reclamation phases of the project as required by <br />