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s <br />mapping unit 2, the ug~m. Soil mapping units 1 and 4 had limited removal <br />and the total acreages per unit were small compared to mapping unit 2 (See Map <br />1). Table 3 shows the removal depths and acreages for all soil mapping units and <br />volume of soil removed. ' <br />The topsoil removal contractor was instructed to remove all topsoil between 18" <br />and 24". In a few areas only 12" of soil was removed due to small rock outcrops <br />overlain by shallow soils. To compensate for this, extra topsoil from areas with <br />deQp soils was taken. The 18 to 24" removal depth was deemed sufficient to <br />reclaim the mine site and meet the 13" stipulated requirement. The decision was <br />also influenced by the inability to store the total amount of potential topsoil on the <br />disturbed areas of the mine site at the time of remova use the topsoil <br />ockpile area was not large enough to contain the total topsoil volume availab e. <br />Also, in many cases excavation was not required for construction purposes to <br />depths below the potential topsoil removal depth. <br />On November 1 the total topsoil value in both stockpiles (see Map 1) was <br />between 58000 and 60000 yd3 as evidenced by an engineering survey of the <br />stockpiles. This volume is sufficient to replace seedbed material on approximately <br />24 acres of the 23 permanently disturbed acres to a depth of IS". This would leave <br />4 acres without seedbed material. Several explanations as to the lack of 9500 yd3 <br />of seedbed material needed to cover the remaining 4 acres are listed below: <br />I) The topsoil was compacted into the topsoil stockpile therefore, showing <br />a smaller volume. <br />Z) There may be an inaccuracy in the surveyed topsoil stockpile cross <br />sections due to the very irregular terrain on which the larger stockpile is <br />located. <br />4 <br />