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Once topsoil is removed, soft upper overburden (Bench 1 or Unit 1 material) is normally <br />removed by the shovel and truck fleet and taken to the back of the previous pit for backfilling <br />using the same temporary road around the end of the pit. A significant amount of this Bench 1 <br />material is typically placed immediately below the topsoil. The amount of Bench 1 placed varies <br />per area, and these thicknesses are shown on Map 2.05.4-4. <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 <br />trucks dump off the backfill spoil dump, large dozer(s) will final grade the truck dump area into <br />the final pre topsoiled contours. This overburden is always buried beneath several feet of Bench <br />1 in 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 <br />be removed. The major advantages of scarification are related to the physical properties of the <br />spoil. The topsoil and Bench 1 are scarified to decrease compaction, increase aeration and water <br />movement, and increase plant rooting depths. Increased water movement may, to some degree, <br />allow more downward leaching of carbonates. Therefore, although the greatest benefits of <br />scarifying are related to the physical soil properties (density, porosity), a lesser geochemical <br />benefit (increased 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 <br />Bench 1 will be sampled prior to topsoil replacement with a hydraulic soil sampler, a bucket <br />auger, or other suitable equipment. Personnel will inspect the surface spoil between sample <br />points. If a significant change in characteristics is observed between sample points, additional <br />sample sites will be located. The lateral and vertical sampling intensities are closely evaluated <br />once sufficient samples are collected to determine the degree of sample variability. This <br />sampling program will ensure that the redistributed soil and spoil is chemically and physically <br />suitable for the intended crops. See Table 2.05.4(2)(d)-1 for all sample parameters, increments, <br />and frequency. <br />July 2018 (TR -84) 2.05.4(2)(d)-3 <br />