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truck fleet handling due to the thinness of Units 2 and 4 and the stratification of alkaline and acidic <br />strata. Normal overburden /interburden handling operations also effectively bury the acid - forming <br />strata. <br />Typical overburden /interburden handling operations are described in Section 2.05.3, Operation <br />Plan and Section 2.05.4(2)(c), Backfilling and Grading. <br />Once topsoil is removed, soft upper overburden (Bench 1 or Unit 1 material) is normally removed <br />by the shovel and truck fleet and taken to the back of the previous pit for backfilling using the same <br />temporary road around the end of the pit. A significant amount of this Bench 1 material is typically <br />placed immediately below the topsoil and subsoil. The amount of Bench 1 placed varies per area, <br />and these thicknesses are shown on Map 2.05.4 -4. Some of this Bench 1 will be used as subsoil, <br />see Map 2.05.4 -7. <br />Lower overburden (Bench 2) is usually cast blasted, dozed and loaded /hauled with shovel and <br />trucks and placed in the previous mined out pit for backfilling purposes. As the overburden trucks <br />dump off the backfill spoil dump, large dozer(s) will final grade the truck dump area into the final <br />pre topsoiled contours. This overburden is always buried beneath several feet of Bench 1 in <br />reclamation. <br />The regraded spoil will be mechanically loosened and mixed by ripping, chiseling, or approved <br />alternate forms of scarification. Rocks discovered during scarification on Irrigated Cropland will be <br />removed. The major advantages of scarification are related to the physical properties of the spoil. <br />The topsoil and spoil are scared to decrease compaction, increase aeration and water movement, <br />and increase plant rooting depths. Increased water movement may, to some degree, allow more <br />downward leaching of carbonates. Therefore, although the greatest benefits of scarifying are <br />related to the physical soil properties (density, porosity), a lesser geochemical benefit (increased <br />rate of carbonate leaching due to increased water movement) may result. <br />4.0 Redistributed Soil and Spoil Monitoring Program <br />In order to provide a feedback system to check the reliability of the overburden sampling and <br />analysis program, a redistributed soil and spoil sampling program is in place. The redistributed soil <br />August 2013 (PR -08) 2.05.4(2)(d) -3 <br />