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volume of the topsoil available from mine development work at any one time. <br />The topsoil stockpile noted at the northeastern end of the affected lam is a <br />potential location identified for future use based on progression of mine bench <br />development and ore body extraction in the future. Specifically, by the time that <br />mining of the ore body has progressed to location of the potential topsoil <br />stockpile, the soils will have bees placed on reclaimed areas directly south of the <br />potential storage location (mined out and regarded areas). <br />9. The text of the permit amendment proposes topsoil placement between 6" and <br />12" based on a gross estimate of total topsoil that may be available for salvage <br />and use in order to allow for a reasonable degree of flexibility for the mine <br />operator This estimate was based on empirical site evaluation of a wide range of <br />soil thickness measured at a number of site locations. Soil thickness did range up <br />to six feet at some limited locations, but also appeared to be only a few inches at <br />most at other locations. The Soils Map Complex submitted was gleaned from <br />NRCS data for Chaffee County and is not site specific in so faz as realistic <br />estimates of soil available without a much more detailed sampling program. The <br />estimate of soils to be salvaged was intended to be a realistic starting point for <br />bond calculation purposes. The 196,289 CY estimate gleaned from the Soil Map <br />Data is a grossly overestimated volume assuming that all areas contain the <br />maximum thickness of soil as listed. 'This is obviously not the case at this site. <br />The operator will commit to the salvage, stockpiling, and use of all topsoil <br />encountered at this site for purpose of reclamation of the site. However, it is <br />unrealistic to assume that topsoil volumes are anywhere neaz the maximum <br />amount projected by the data presented in paragraph 9 of the DMG comment <br />document The operator does feel siro~ly that 1.7' of topsoil is ~ rr~iistbc <br />and un-necessary depth of cover and should not be construed to be used as a <br />standard for future reclamation or bond calculation. The operator shall consider a <br />range of topsoil depths based on location, grade, and soil availability at the time <br />of future reclamation work. <br />10. The one acre staging area located adjacent to Highway 50 is on a former railroad <br />right-of-way. No top-soil e>cists at this loprioa The operator will agree to haul <br />up to 1' of topsoil from the mine site to the staging area for final reclamation and <br />comnnit to bonding to reflect said haulage and re-vegetation cost <br />11, As stated in the mine plan narrative, tine 17, page 6, an evaluation of rock <br />characteristics will be performed after top bench development has progressed to <br />a point where un-weathered bedrock is exposed. The initial mine plan assumes a <br />wider bench width will be necessary near the top of highwall bench configuration <br />and that minimum bench width will likely decrease as increased rock hardness is <br />encountered with increasing depth of mine bench development The final bench <br />width configuration will be determined based on rock hardness, susceptibility to <br />weathering, and structural controls are evaluated for the quartzite footwall <br />bedrock material. The narrative and typical cross section Exhibit Cd are <br />