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<br />Exhibit E -Reclamation Plan (continued) <br />M The resulting peak flow is 8.30 cfs. The ditch will be a trapezoidal ditch of 2% grade and bottom <br />width of 3.0 feet. Sideslopes will be 2.OH:1.OV and the total depth will be 2.0 feet. Freeboard will <br />be I.0 feet. Using a Manning's n of 0.025 for coarse gravel lining, the ditch is capable of handling <br />10.5 cts at a flow depth of 0.55 feet and a velocity of 4.67 ft/second. This velocity is low enough to <br />avoid erosion when using coarse gravel of a D50 of 10 inches. Since the ditch will actually be 3.0 <br />feet deep with freeboard, the safety factor for the design flow is very large. <br />Any groundwater collection ditches or pipes need to convey groundwater to the unnamed drainage, <br />as described in the section on Water Control and Detention Structures of Exhibit D, will be kept in <br />place for the post-mining condition. <br />3. Soil Replacement <br />. The sequence of stripping and stockpiling soil is described in the section on Topsoil Handling and <br />Storage of Exhibit D. For replacement, scrapers, loaders, trucks and dozers may be used to replace <br />the soil. Extreme care will be taken to ensure that all soil is relieved of compaction prior to seeding. <br />Harrowing or ripping may be utilized to accomplish this task. Considerable data has demonstrated <br />that soils placed with heary equipment and no compaction relief take decades or longer to produce <br />normal levels of vegetation. <br />Estimated soil replacement depth is 6-8 inches, which is equal to that stripped from the site prior to <br />mining. B&:B commits to a minimum of 6 inches of replaced topsoil for all reclaimed areas. <br />Salvaged fines from the processing operation will also be used as a growth medium or root zone <br />layer if available in sufficient quantities, and if soil tests on this material show it is suitable as a <br />growth medium. This may be valuable since the gravel is very porous and has poor water retention <br />capability. Without irrigation, the vegetation on the existing site dries out easily and is not very <br />productive. The addition of fines prior to true soil replacement may improve the water retention <br />. capability of the soil and consequently, the post-mining vegetation. <br />Carol Ann Perrrtit CDMG Application 2 8 <br />