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SaYime - ?.04.9 Typically, upland soils such as those occumng in the upper Hubbard and Bear Creek areas are either • of the BeenorrrAbsarokee association or the Kech-Rock outcrop complex Soils on the lower slopes of the ridgelines and the upper side-slopes of area drainages, as Identified in the lower Beaz Geek and upper Elk Geek areas and the lower side-slopes between Elk and Bear Geeks, are typically of the Tomorthenu-Rock outcrop, sandstone, complex On the lower drainage slopes in Elk Geek and in the ephemeral drainages to the west, the Tortiotthents-Rock outcrop, sandstone complex grades into the Torrionhents-Haplargids complex which occurs as limited alluvia] fans at the outlets of the small ephemeral drainages. Soils Surveys -A number of soil surveys have been conducted over the life of the current and historic mining aciivities. Given the limited surface disturbance associated with the ongoing mining operations, these surveys have been condutted in conjunction with and have focused on specific disturbance activities and the associated disturbance areas. A tabulation of soil sample locations in the pre-law Beaz Creek, Hubbard Creek, and Elk Geek disturbance areas (1980 sample analyses) as well as more recent samples from the Elk Creek, Substation No.3, and West Valley Fill post-law disturbance areas is presented as Table 2.04.9-T1, Soil Sampling Summary. The following summaries soil survey efforu to date (Note: Because the soil surveys were done at different times and by different parties, there is some variance in the level and nature of available documentation): Pre-Law Disturbance Areas - Milling operatiotu in the mine permit area were initiated as early as 1901, therefore, much of the presently affected area was disturbed prior to 1977 and soil materials from these areas were not sampled, characterized, salvaged, or segregated. Several of these previously disturbed areas have, however, been evaluated relative to soil conditions and some have been sampled for soils analyses (1980 and 1983 supplemental sampling programs). Where evaluation and sampling of pmlaw disturbance areas have not occurred, soils desmptions are based on the available soils inforration from the USDA-SCS soil survey report. The following are pre-law disturbance areas and • the associated soil mapping uniu based on the avai]able soils information: Hubbard Geek - BeenonrAbsarokee association grading to Kech-Rock outcrop complex Beaz Geek (Upper undisturbed) - Absarokee•Work loam Bear Creek (Disturbed) - Tortiorthenu-Rock outcrop, sandstone, complex Elk Geek - Tor:iorthent-Rock outcrop, sandstone complex grading to Tomorthent- Haplargids complex 1987 Disturbed Area Soil Depth Evaluation -Soil pie were excavated in disturbed auras on the east bench, central yard, and west bench areas to evaluate the depth of any rert+~ir~rg soils in these areas and identify the types of subsurface materiak present. In general, the existing disturbance areas, except for the west bench area, had little remaining soil, and surface and subsurface materials consisted of mixed soil, coal refuse, coal, and ash. In the west bench area, a coolly layer less than (r inches in thickness overlies minimally disturbed subsoil. In this area, the surface layer can either be removed and used as sub-grade fill or tipped and blended into the existing soil material to support revegetation efforu. The following s~~m~*+~~>PS the results of the soil depth evaluation: Location Depth Interval Material Description East Bench (I-1~ East Bench (K-K~ East Bench (ivI-M~ Central Yatd (F-F' Lower) • Central Yard West Bench (B-B~ 0-6' 0-7.5' 0-2.1' 2.1-6.5' 0-6' 3-5.5' 0-1' 1-2.5' 2.5-4' Coal Refuse Coal Refuse Subsoil Coal Refuse Coal Refuse and Ash Subsoil and Rock Coolly Material Subsoil Coal and Subsoil PR04 2.0485 Revised August ?000