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Topsoil and spoil samples are shipped to Servi-Tech Laboratories in Hastings, NE for <br />• analysis. The analytical results (see Attachment 2007-A) indicate that all samples are <br />suitable. No additional grading, special handling, or amendment application is needed. <br />Soil Redistribution <br />In general, the topsoil that was used for redistribution is live handled from ahead of the <br />active mining area to the awaiting backfill area. Because the material is moved by mine <br />equipment and is scheduled amongst the other mining functions, discrete topsoil <br />campaigns as done in the past are no longer conducted. Occasionally, mining parameters <br />require that some topsoil be stockpiled adjacent to a laydown area prior to spreading. <br />Topsoil Thickness <br />The thickness of soil replaced during 2007 was verified by 5 sample sites. Sample sites for <br />the New Horizon 2 mining area were selected systematically utilizing a 465 foot by 465 foot <br />grid pattern. Sites at New Horizon 2 were determined from CAD drawings using distances <br />and azimuths from established survey points and located in the field by a handheld GPS <br />unit. <br />A 2-3/4 inch hand auger was used at each site to excavate a pilot hole through the entire <br />soil strata. An abrupt boundary, defined by color and rock fragment content, typically <br />occurred at the soil/spoil interface. The replaced soil thickness was measured through the <br />pilot hole immediately after encountering the spoil. Minor Revision # 44 was approved by <br />DMG in August 2000. The revision, based on years of extensive sample analysis, allowed <br />• for a reduction in the parameters for which the soil is analyzed. <br />Soil thickness as determined by past sampling is shown on Exhibit 2007-6. Soil thickness <br />information for Each sample site is located on the map. The average topsoil thickness for <br />the 2007 sampliing session is approximately 2.0 feet. The New Horizon 2 has a minimum <br />requirement of "...approximately 1.0 foot for topsoil laydown thickness." (2.05.4(2)(d)-13). . <br />New Horizon 2 has many different soil thickness requirements as shown on Map 2.05.4-4 <br />in section 2.05(2)(d) of the current Permit C-81-008. Exhibit 2007-8 shows the type and <br />area of the reclaimed land. <br />Topsoil SalvagE: and Storage <br />All suitable soil has been salvaged ahead of mining at New Horizon 2. Approximately <br />10,790 cubic yards (Pre 1995 LIFT 1), 66,025 cubic yards (Pre 1995 LIFT 2), 41,760 cubic <br />yards (Pre 1995 MIXED) and 207,475 cubic yards (2007 Topsoil), a total of 326,050 cubic <br />yards of soil arE: stored in all stockpiles at the end of 2007. The total of Lift 1, Lift 2, and <br />Mixed; 118,575 cubic yards, 74,850 cubic yards is required for backfill. A total of 173,110 <br />cubic yards will be needed to replace 2007 disturbance leaving 34,365 cubic yards excess. <br />The total topsoil balance EOY 2007; 109,215 cubic yards excess. Exhibit 2007-10 (2007 <br />Topsoil BalancE: Map) gives details. The soils were separately stockpiled by soil types as <br />specified by our• permit. All topsoil piles were resurveyed and recalculated in 2007. <br />• <br />F:\Eng\DATA\Word\i~nn Reclaim Report\2007\2007RECRPT.doc <br />