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Small Depressions Small depressions are not proposed at the New Horizon Mine. See Map 2.05.4- <br />2 for the postmining topography. <br />Steen Slopes New Horizon Mine does not have steep slopes as defined in the regulations. <br />Final Gradino. Final grading and preparation of the backfilled material before placement of topsoil <br />material will be done along the contourto minimize subsequenterosion and instability. If such grading <br />is hazardous to equipment operators, then grading will be done in a direction other than generally <br />parallel to the contour. <br />Final Pit Backfilling. In order to eliminate any final highwalls and to achieve the approximate original <br />landform, some highwall materialwill be pushed or dozed into the mined area. Map 2.05.4-3 shows <br />typical cross sections of the fill material placed into the mined pits. Material above the final highwall <br />may be blasted or ripped and then graded to blend into the surrounding topography. <br />Thin and Thick Overburden <br />The New Horizon 2 permit area does not meet the requirements of either the thick or thin overburden <br />. as shown by the following calculations: <br />90.0' maximum stripping depth <br />50.0' average overburden <br />5.0' Lower Dakota <br />S (REVISED 9/99) 2.05.4(2)(C) - 2 <br />