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Sarin: ~ 2.04.9 1997 West Valley Fill Soil Survey - In preparation for pemvtting of the West Valley Fill, soils on the • lower ridgelines, drainage sideslopes, and at the oarless of small ephemeral drainages between Elk and Beaz Creeks were examined and sampled. Generally, the soils on the lower ridgelines and drainage sideslopes were Tomorthent-Rock outcrop, sandstone complex grading to Torriorthent-Haplargids complex. The only additional soil unit identified was a Haplargid soil ass«iated with small alluvia] fans at the outlets of the ephemeral drainages in the sampling area. 1999 Ells Creek Mine Facilities Area Sampling - In conjunction with permitting of the Elk Creek Mine surface facilities, three soil samples were obtained in the proposed mine disturbance areas and analysed or tested for chemical and/or physical characteristics. Otte bulk grab sample (SSO) was obtained at the base of an existing natural slide in order to evaluate the physical properties of slide materials for use in construction of the Elk Creek Mine portal benches and ass«iated roads. A consolidated un-drained compression test was performed on the sample with results as outlined in Exhibit 2.05-E2, Geotechnical Design and Stability Analyses. The other two soil samples were collected at the upper (S02) and lower (SO1) ends of the planned mine disturbance area in the vicinities of the upper and lower mine portal benches. Soil horizons and depths were logged during sample collection and samples were analyzed for basic soil suitability parameters. Soils were primarily sandy clay looms and clay looms and depths ranged from 4 to 24 inches before heavy clays or high r«k content soils were encountered that would limit soil suitability. Mapping Unit Descriptions -The following are mapping unit descriptions from the USDA-SCS soil surveyreport for the-mapping tutits`identified bysite-specific soils evaluations and shown on the Regional Soils Map~(Map 2.04-M4): /) Absazokee-Work loam -This soil u a moderately deep, well-drained soil formed from weathered sandstone and reworked eolian materials. The soil is positioned on the steeper slopes, small ridges on • the uplands and valley sideslopes. The Absarokee soil makes up about 40 percent of this complex and a on the steeper sideslopes and on small ridges. The Work soil makes up about 40 percent and is in depressions and swales. Included in this complex are small area of ocher soil types making up approximately 20 percent of the complex For the Absarokee soils, the surface layer is a loam that varies from 0 - 7 inches thick with a clay subsoil approximately 18 inches thick The substrate u channery clay loam over sandstone at a depth of about 30 inches. For the Work soils, the surface layer is a loam approximately 6 inches thick with a clay subsoil approximately 33 inches thick The substrate u a channery loam extending to a depth of 60 inches or more. Perrneabilities for the surface and subsurface are moderate (0.6-2.0"/hr.) and slow to very slow (0.2- 0.6"/hr.), respectively and available water capacities for the Absarokee and Work soils are low and high, respectively. Surface runoff is medium and erosion hazard u slight from wind and moderate to high from water. These soils typically support native vegetation convicting mainly of Gambel oak, serviceberry, big sagebrush, wheatgrasses, and bromes. Ass«iated uses include hues[«k grazing, wildlife habitat, and recreation. Shrink-swell potential is moderate to high. The risk of corrosion is high for uncoated steel and low for concrete. Potential frost action u low. BeenorrrAbsarokee Ass«iation -Thin is a shallow to moderately deep, well-drained soil formed from weathered sandstone and interbedded shale materials. These hilly, steep, and very steep soils are on mountain sideslopes. The Beenom soil makes up about 50 percent of the ass«iation and u on the upper part of the slopes and the ridgetops. The Absazokee soil makes up about 30 percent of the ass«iation and u on the lower slopes and in swales. The remaining 20 percent of the ass«iation include small areas of other soils, r«k outcrops, very shallow soils, and deep stony soils. For the Beenom soils, the surface layer is loam about 4 inches thick over a clay loam subsoil approximately 5 inches thick The substrate is channery loam over sandstone at a depth of 14 to 20 inches. For the • Absarokee soils, the surface layer is a loam that varies from 0 - 7 inches thick with a clay subsoil approximately 18 inches thick The substrate is channery clay loam over sandstone at a depth of about 30 inches. PR04 2.04-88 Revised August 2000