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TDN Response Page 8 <br />New Horizon Mine <br />April 23, 2010 <br />Topsoil replacement, was shown on Map 2.05.4 -4, Postmining Topsoil Replacement, and discussed in <br />Section 2.05.4 (2)(d), Topsoil Redistribution. Four separate blocks were designated within the PR -5 <br />area with varying depths of replacement for Lift -1 and Lift -2 as shown on Map 2.05.4 -4. On the <br />Morgan property, a minimum of 1.14 feet of the A horizon and upper portions of the B were to be <br />salvaged in Lift -1, and a minimum of 2.26 feet of the lower portions of the B and portions of the C <br />horizon were to be salvaged in Lift -2. Each soil lift was to be stockpiled separately. Soils within the <br />Darvey -Barx unit were to be replaced with a total projected thickness of approximately 3.4 feet for <br />Lift -1 and Lift -2 combined. This replacement plan was approved on the Morgan property to ensure soil <br />productivity would support the approved post - mining land uses of irrigated pastureland and irrigated <br />hayland. <br />In addition to the topsoil, handling of the Bench 1 material has been an important component of the <br />reclamation plan at the New Horizon Mine. Bench 1 Material is below Lift -2 in the stripping sequence <br />and is the soft upper overburden consisting of weathered sandstone and shale bedrock that has <br />decomposed and is mostly friable. It vanes from 10 to 30 feet deep and it grades imperceptibly into <br />the overlying soil. Bench 1 material is mechanically removed as a separate unit and is the last <br />overburden unit to be placed over the reclaimed mine. (Walsh Report, 2008) This material is also <br />referred to as suitable subsoil. <br />Subsequent to the issuance of PR -5, there were several revisions that revised the topsoil management <br />plan. These are discussed below. <br />Minor Revision No. 51 (MR -51) was submitted October 1, 2001 and approved on October 16, 2001. <br />This revision description is, `modify exhibit maps to include additional acreage'. The cover letter <br />dated September 25, 2001 states that Exhibits [Maps] 2.04.10 -1, 2.04.11 -1, 2.05.2 -2, 2.05.2 -3, 2.05.4 -4 <br />and 2.05.4 -5 were revised to include the Reeder and Garrett properties. However, it appears that <br />changes other than boundary modifications were made to Map 2.05.4 -4, `Topsoil Replacement Map'. <br />On the version of Map 2.05.4 -4 received February 10, 2000 (presumably during the PR -5 review), four <br />separate topsoil replacement Blocks (A -D) are shown for the PR -5 area. The Morgan property is in <br />Block A where it is indicated that 1.14 feet of Lift-I material and 2.26 feet of Lift -2 material will be <br />replaced. <br />On Map 2.05.4 -4 received with MR -51 on October 1, 2001, the Block labels were removed. Two -lifts <br />of replacement were indicated for the Morgan property. However, based on the revised map table, the <br />Morgan Lift -1 was reduced from a minimum of 1.14 feet to 0.83 feet and Lift -2 was reduced from a <br />minimum of 2.26 to 1.00 feet. An asterisk on the table indicates the Lift-2 Material could be suitable <br />subsoil. Suitable subsoil is not described. <br />Minor Revision No. 57 (MR -57) was submitted on March 14, 2002 and approved on April 1, 2002. <br />The description for this revision is, `Changes to Topsoil Salvage Techniques'. The cover letter dated <br />March 12, 2002 proposes to change Section 2.05.4(2)(d) pages 11 thru 13. Section 2.05.4(2)(d) of the <br />permit was amended to add a section titled, Topsoil Salvage Techniques — Year 2001 and onward. <br />This plan does not distinguish between the various soil map units or the four Blocks approved in PR -5. <br />All topsoil salvaging and replacement is combined into a single plan as follows: <br />