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The non prime farmland topsoil stripping procedures for this area is as follows: Since Lift A <br />thicknesses are from 6 -13 inches and Lift B thicknesses are also relatively shallow (8" to 22 "), Lift <br />A and B will be combined into one lift of mixed topsoil because it is very difficult to strip thicknesses <br />of approximately 6 -8 inches with such large mining equipment. The Survcadd thickness averages <br />for the non prime farmland fields west of the pit in February 2008 show 7.1 inches for the average <br />of Lift A and 17.4 inches of Lift B. See Table 2.04.9 -8C. Using 80% of the soil sample average to <br />obtain a stripping average for the area, this results in 5.7 inches for Lift A and 13.9 inches for Lift <br />B. Therefore, the total average stripping thickness for the combined Mixed Topsoil ( Lift A and Lift <br />B) is 19.6 inches. The expected range is from 8 inches to 38 inches. The mine foremen and <br />operators will be trained on the stripping of the mixed Lift A & B, and will know to stop the removal <br />when coarse fragments have a rise from less than 10% volume in Lift B to material that has <br />significantly higher coarse fragments (20- 25 %),Insomecases, bedrock will be encountered atthe <br />end of Lift B in the non prime farmland areas. <br />An additional amount of suitable subsoil, which is basically the Bench 1 overburden material, will <br />be stripped and placed as shown on Map 2.05.4 -4. The Benson West property basically has <br />already been backfilled with a minimum of 30 inches of this material. The Lloyd property will receive <br />a minimum of 30" of this material and the WFC property will receive a minimum thickness of 24" <br />of this Bench 1 material. For the purposes of the volume calculations, the suitable subsoil material <br />on the Benson West is assumed to be 30" in thickness, and Lloyd property is 30" and the WFC <br />property will be 24" in thickness. These amounts allow a minimum of 48" total suitable medium on <br />the Benson and Lloyd properties and 44" on the WFC property. <br />Topsoil is stripped using a combination of dozer, truck - shovel, and dump truck. Mixed Topsoil is <br />windrowed by dozers into a pile, from which a truck - shovel loads the dump truck. The dump truck <br />then either dumps the topsoil material at a designated location that is being retopsoiled, or dumps <br />the material at a designated topsoil stockpile site. Determination of topsoil stipping limit is based <br />on a combination of the location of topsoil stripping (based on soil surveys) and color differences <br />between the topsoil and overburden. <br />Revised September 2010 (PR 06) 2.04.9 -39 <br />