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to be disturbed on steep, southfacing slopes. The very thick Silas loam soil developed from <br /> alluvium within narrow bands along the larger ephemeral drainages. <br /> The predominant hill-slope soils have relatively thick, loamy textured mollic epipedons, well <br /> suited for reclamation use. Salvageable thickness of these soils averages from 12 inches to 30 <br /> inches. Subsoils in these units are somewhat marginal, due to heavier texture or excessive <br /> cobbles. The Silas loam soil along the drainage valley bottoms is generally suitable for salvage <br /> to depths of five feet or more. <br /> B. Topsoil Salvage Operations <br /> Information on topsoil salvage methods is found in Sections 2.04.9, 2.05.2 and 4.06 (Volume 1 <br /> for the East Pit, West Pit, Section 16 Pit, Facilities Area and Gossard Loadout; Volume 12 for <br /> South Taylor Pit; Volume 15 for Collom Pit) of the PAP. In general, the topsoil handling plan <br /> calls for removal of all of the A and some or all of the B horizon materials, depending on soil <br /> type. Average estimated soil salvage thicknesses map units (based on component series relative <br /> acreage) is presented in Tables 2.04.9-6 and 6A in the PAP. Projected salvage volume <br /> calculations for defined topsoil stripping blocks area are presented in Table 2.04.9-7 in the PAP. <br /> Specific areas where topsoil will not be salvaged are described in Section 4.06 of the PAP. <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 /> 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 /> In 1981 Colowyo committed to include information in its annual reclamation reports to verify <br /> that enough topsoil was being salvaged to replace a sufficient amount of soil on regraded areas. <br /> This information was reported until 1986. The Division suspended this monitoring requirement <br /> in 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 <br /> requirement was reinitiated in association with TR-62 approved on May 29, 2006, and reporting <br /> resumed with submittal of the 2005 Annual Reclamation Report. The resumption of the annual <br /> reporting requirement was largely due to the fact that Colowyo became aware, based on a soil <br /> balance assessment in 2005, that there was insufficient topsoil in stockpiles to meet the 18-inch <br /> average replacement thickness requirement for disturbed areas that had not yet been topsoiled. <br /> An overall lifeofmine topsoil balance for the Colowyo Mine can be found in the 2017 Annual <br /> Reclamation Report. <br /> Proposed Decision and Findings of Compliance January 5,2023 <br /> Permit Renewal No. 8 Page 144 <br />