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TDN #X11 - 140 - 182 -001, Additional Information Page 2 <br />New Horizon Mine <br />February 22, 2011 <br />PR6 was issued on December 8, 2010. In PR6, the requirements for ripping were revised for areas not yet <br />topsoiled to specify, "large boulders will be graded off the freshly ripped Bench 1 area so as not to poke up <br />through a portion of the Lift B topsoil or Bench 1 substitute subsoil" (Section 2.05.4 subsection 13.1 of the <br />permit). <br />With the approval of Permit Revision No. 6 (PR6), the approved topsoil depths also were revised. The <br />average topsoil depth in Zone 1 is seventeen inches. The approved topsoil depth in Zone 1 is a minimum of <br />eighteen inches and an average of twenty -one inches. Therefore, additional topsoil in Zone 1 will be required <br />to achieve the approved depths. <br />After placement of topsoil PR6 also requires that land leveling and rock picking be conducted on all prime <br />farmlands. Land leveling and rock picking will be conducted in Zone 1 after the topsoil on the Morgan <br />property is at the correct depth. <br />The Division required WFC to evaluate the suitability of the Bench 1 material in February 2008,when the <br />prime farmland was recognized. Zones 1 and 2 on the Morgan property had been already been backfilled with <br />overburden, and topped with a thickness of "Bench 1" substitute subsoil material in preparation for subsequent <br />topsoil redistribution. WFC was directed by the Division to evaluate the emplaced "Bench 1" material to <br />determine if it was suitable to be used as subsoil on prime farmlands. Sample criteria included % rock <br />fragment. The results of the 2008 suitability study conducted by Walsh Environmental are reported in <br />Attachment 2.05.4(2)(d) -1 of the permit. The results show that the replaced Bench 1 material is a suitable <br />subsoil. The Walsh study and the Division evaluation of the results were included in the TR57 and the PR6 <br />review. <br />Rock fragments will be sampled on all future and not yet topsoiled subsoil replaced on the Morgan Property. <br />Table 2.05.4(2)(d) -lA of the permit, Spoil and Soil Suitability Criteria (Morgan Prime Farmland) provides the <br />criteria and threshold levels. A copy of this table is attached for your information. <br />To summarize, 7.81 acres were topsoiled on the Morgan property prior to the approval of PR6. With the <br />approval of PR6 the depth of the upper lift of topsoil has increased. Additional topsoil is required in Zone 1 to <br />achieve the final required depth. At the time topsoil was initially placed, there were no standards in place for <br />subsoil rock removal. To evaluate whether or not the emplaced Bench 1 material would be suitable as a prime <br />farmland subsoil, the Division required WFC to evaluate the Bench 1 material. This evaluation was completed <br />by Walsh and the results showed that the Bench 1 material was a suitable subsoil. After the additional topsoil <br />is replaced on the 7.81 acres in Zone 1 WFC is required land level and rock pick the reclaimed area prior to <br />seeding. <br />Please consider this revised response for TDN #X11 - 140 -182 -001. If OSMRE has any further questions or <br />needs additional clarification on this response, please contact me. <br />Sincerely, <br />r <br />' A. Berry <br />ire r, Office of Mined Land Reclamation <br />Attachments Excerpt of Map 2.05.4 -6, Morgan Property Topsoil Replacement <br />December 18, 2009 Aerial photo <br />Table 2.05.4(2)(d) -IA, Spoil and Soil Suitability Criteria (Morgan Prime Farmland) <br />