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<br />Proposed Decision and Findings of Compliance July 2018 <br />Permit Renewal No. 7 P a g e | 41 <br />B. Topsoil Salvage Operations <br /> <br />Information on topsoil salvage methods is found in Sections 2.04.9, 2.05.2 and 4.06 (Volume 1 for <br />the East Pit, West Pit, Section 16 Pit, Facilities Area and Gossard Loadout; Volume 12 for South <br />Taylor Pit; Volume 15 for Collom Pit) of the PAP. In general, the topsoil handling plan calls for <br />removal of all of the A and some or all of the B horizon materials, depending on soil type. Average <br />estimated soil salvage thicknesses map units (based on component series relative acreage) is <br />presented in Tables 2.04.9-6 and 6A in the PAP. Projected salvage volume calculations for defined <br />topsoil stripping blocks area are presented in Table 2.04.9-7 in the PAP. Specific areas where <br />topsoil will not be salvaged are described in Section 4.06 of the PAP. <br /> <br />Topsoil is removed during the late spring to fall, ahead of pit advancement. Vegetation, with the <br />exception of large trees, will be removed and redistributed with the topsoil. Topsoil will be <br />removed to topsoil stockpiles or, where possible, applied directly to regraded spoil. Within the <br />South Taylor Pit and Collom Pit areas, most topsoil will be placed in stockpiles, as the nature of <br />the operation will generally not allow for direct replacement. <br /> <br />Topsoil stockpiles are shown on Maps 22, 28, 28A, 28B, and 28C of the PAP. Additional <br />stockpiles located at the Gossard Loadout are located in the northern portion of the permit area <br />and are shown on Map 25G of the PAP. All soils stockpiles will be protected from erosion and <br />will not be moved without Division approval. <br /> <br />In 1981 Colowyo committed to include information in its annual reclamation reports to verify that <br />enough topsoil was being salvaged to replace a sufficient amount of soil on regraded areas. This <br />information was reported until 1986. The Division suspended this monitoring requirement in <br />1987, as the data indicated that sufficient topsoil would be available to meet reclamation needs <br />throughout the life of the mine. The Annual Topsoil Balance inventory and reporting requirement <br />was reinitiated in association with TR-62 approved on May 29, 2006, and reporting resumed with <br />submittal of the 2005 Annual Reclamation Report. The resumption of the annual reporting <br />requirement was largely due to the fact that Colowyo became aware, based on a soil balance <br />assessment in 2005, that there was insufficient topsoil in stockpiles to meet the 18-inch average <br />replacement thickness requirement for disturbed areas that had not yet been topsoiled. <br /> <br />An overall life-of-mine topsoil balance for the Colowyo Mine can be found in the 2017 Annual <br />Reclamation Report. <br />C. Topsoil Redistribution <br /> <br />Topsoil redistribution for the Mine is described in Sections 2.05.3(5), 2.05.4(2)(d), and 4.06 <br />(Volume 1 for the East Pit, West Pit, Section 16 Pit, Facilities Area and Gossard Loadout; Volume <br />12 for South Taylor Pit; Volume 15 for Collom Pit) of the PAP. Regraded spoils will be scarified, <br />where necessary, before replacement of topsoil by truck and loaders and dozers. Where necessary, <br />a drainage control bench or furrow will be constructed on spoil slopes of 3:1 (horizontal to <br />vertical). Topsoil will then be applied in a rough condition, chiseled to relieve compaction and