2008-02-04_PERMIT FILE - C1982056A

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a.oy .9 Order 2 soil surveys within the proposed permit area. In August of 1984, Twentymile Coal Company refined the • existing SCS map by conducting an Order 1 survey in the areas of planned disturbance. Disturbance along Foidel Cheek existed a[ [ha[ time; therefore, [he soils in this area are mapped according to the Order 2 soil survey. All work was performed under the supervision of a certified professional soil scientist and soil classifier. SCS mapping was field checked, verified, and refined as needed, using observations collected from holes bored with a hand auger or dug with a spade. Observations were spread along transects across dtese areas at a density of at least one boring per 5 acres. Soil excavated from each boring was field evaluated and characterized in accordance with standard SCS field procedures. Black and white stereo-paired photographs (scale I :12,000) were used during [he field work to assist in boundary definition. These soil boundaries are presented on Map 17, Premising Soils. Soil descriptions are presented in Exhibit I5, Typical Pedon Descriptions and Exhibit 16, Soil Mapping Unit Descriptions. PEDON DESCRIPTIONS AND FIELD SAMPLING Fish Creek Borehole Area The entire Fish Creek Borehole Area was previously surface mined and has since been revegetated. Part of the area was reclaimed in 1976 and the remainder during 1980. Separate composite samples were collected from adjacent areas reclaimed during 1976 and 1980. Samples in the area reclaimed during 1976 were collected from 3 locations and composi[ed by 6 inch increments. Samples in the area reclaimed during 1980 were collected from 7 locations and composited by 6 inch increments. The locations of all sampling sites, presented on Map 17 - Premining Soils, are found within the previously planned Fish Creek Borehole Area. The new site is about 3000 feet west and is located in the same soil and vegetation types; namely reclamation of 1976 and 1980. • Soil samples were placed in clear polyethylene plastic bags after collection and transported to Bookcliffs Commercial Laboratories in Steamboat Springs, Colorado, for analysis. Laboratory Analyses Samples were analyzed using methods recommended by [he CMLRD. Parameters tested included organic matter (percent), saturation percentage, percent sand (100 to 2000 micron), very fine sand (50 to 100 micron), silt (2 to ~0 micron), clay (less titan 2 microns), pH (paste), electrical conductivity (nunhos/cm), soluble calcium, magnesium, sodium, and sodium absorption ration (SAR). Boron and selenium analyses were not performed as no samples Itad a pH of 8.5 or greater and selenium indicator plants were no[ observed in either area. Laboratory data are presented in Table 20, Chemical and Physical Data. A comparison of the analytical data for sample splits showed laboratory precision to be good. Results obtained during the field survey, from laboratory analyses, and from existing data were compiled and evaluated. Suitability ratings of soils as sources of topsoil were developed using [he criteria presented in Table 21, Suspect Levels for Determining Soil Suitability (unpublished CMLRD guidelines, Herron 1984) and Table 22, Criteria for Evaluating Soil Reconstruction Material (USDA, Soil Conservation Service 1978). Topsoil suitability by sample increment is presented in Table 23, Topsoil Suitability by Sample Increment. Soil Suitability Summary All soils in the Fish Creek Borehole area and potential future facility locations are chemically good or fair sources • of topsoil. None of the soils are unsuitable from a chemical or physical standard. Only the upper 12 to 18 inches of the Fish Creek Borehole location soils are suitable for use as topsoil. These soils are extremely stony below the depths of 12 and 18 inches where [he regraded spoil material starts. MR 97-ISd 2.04-48 Revised 10/02/97