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New Horizon Mine TR-57 <br />2nd Adequacy Review <br />21-Oct-2008 <br />Page 6of15 <br />b) Table 2.04.9-6 indicates that for the Morgan property that has not yet been <br />disturbed, an average 40 inch thickness of subsoil material will be salvaged (referred <br />to as "Lift B + Suitable Subsoil" on Table 2.04.9-6). Please address what <br />differentiates Lift B material from "suitable subsoil" material, and how the bottom of <br />Lift B is defined for the purposes of field operations. Presumably, the "suitable <br />subsoil" is essentially synonymous with "Bench 1" overburden, which is the <br />unconsolidated deposits immediately underlying the native subsoil. Will the Bench 1 <br />material be salvaged and replaced separately from the "Lift B" soil horizons, or will <br />some thickness of unconsolidated overburden (as necessary to obtain a total 40" <br />"subsoil" recovery thickness) be included in Lift B recovery operations. Please <br />provide appropriate narrative clarification regarding delineation, recovery, and <br />handling of root zone material beneath Lift A, for the undisturbed portion of the <br />Morgan property prime farmland. <br />Item Resolved <br />c) Narrative on page 2.04.9-23 indicates an average Lift A thickness of approximately <br />7.2 inches for the non-prime farmland soils north of BB Road, which seems <br />reasonable based on the survey data for the dominant soil types. However, this does <br />not correspond with Table 2.04.9-6 entries for the 16.67 acre "Lloyd Undisturbed" <br />property and the 87.76 acre "WFC Undisturbed" property, both of which indicate an <br />18" Lift A thickness. This apparent inconsistency may be a semantic artifact, with <br />"Lift A" being used to mean two different things (in one case referring to the A and <br />upper B horizons, and in the other case referring to the top lift that would be removed, <br />including A, B, and C horizons mixed). It would appear to be intended that an <br />average 18" mixed soil layer would be recovered in a single lift from these areas, with <br />a separate lower lift consisting of Bench 1 overburden material, but the wording is <br />confusing. Please clarify the issues regarding salvage lifts and thicknesses (for soil <br />horizons as well as underlying Bench I overburden) for the non prime farmland <br />areas, and ensure that tables, text, and maps are consistent. Please describe how the <br />bottom of each lift will be identified for salvage in the field. <br />In the amendment package, we note the following: <br />• Narrative on amended pages 2.04.9-26 and 2.04.9-27 explains that a single <br />mixed topsoil lift averaging 19 inches in thickness will be taken from <br />these non-prime farmland soils, with a range in thickness of from 8 inches <br />to 38 inches. Bottom of lift B is defined by either bedrock or significant <br />increase in coarse fragment content, which mine foremen and equipment <br />operators will be trained to recognize. <br />• Narrative further states that additional suitable subsoil below lift B (i.e. <br />Bench 1 material) would be salvaged when present, and would be <br />replaced as subsoil over graded spoil, to provide a combined suitable <br />material replacement thickness (combined mixed lift topsoil and suitable <br />subsoil) of 48" on Benson and Lloyd properties and 44" on WFC <br />property. <br />6