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IIIIIIIIIIIIIIIIIII • ,-z~-~ ~ • lj~~:EXHIBIT I SOILS INFORMATION Affected lands for the Yankee Gulch Project include the solution mining well field and the initial processing plant area at the Piceance Site, a 50-foot-wide permanent corridor along the 44-mile-long pipeline route, and the final processing plant area at the Parachute Site. Soils are described in soil surveys conducted by the USDA Soil Conservation Service (SCS). The Soil Survey of Rio Blanco County Area Colorado (SCS 1982) and the Soil Survey of Rifle Area Colorado (SCS 1985) provide detailed information on the physical and chemical characteristics of soils within the affected lands. Soil characteristics, including soil salvage and reclamation characteristics, are summarized below for soil mapping units within the affected lands. Soil conditions within the affected lands are highly variable due to differences in the soil-forming factors: parent material, topography, vegetation, and climate. The semi- arid environment of the resource area has affected soil development. Lack of moisture, cool nights, a:~d infrequent high temperatures suppress vegetation growth and slow the chemical and biological processes needed for good soil development. In addition, geologic erosion has progressed too rapidly for many soils to develop distinct deep horizons (BLM 1994). Soils in the Piceance Creek Basin occupy varying landforms including drainageways and narrow valleys, rolling hills, and high mountains with very steep side slopes. Slopes range from 0 to 90 percent. Soils are shallow to deep and have formed in alluvium, colluvium, residuum, and reworked eolian deposits derived predominantly from shale and sandstone (SCS 1982). Native vegetation ranges from streambank riparian shrub communities along perennial streams to sagebrush communities that occur at all elevations, mountain shrub communities at higher elevations, and pinyon-juniper communities on shallow soils on mountainsides and ridges. Major uses include wildlife habitat and livestock grazing. Soils are considered fragile when they exhibit the following criteria: • Areas rated as highly or severely erodible by wind or water, as described by the SCS. • Areas with slopes greater than 35 percent if they have one or more of the following soil characteristics: (a) surface texture that is sand, loamy sand, very fine sandy loam, fine sandy loam, silty clay or clay, (b) a depth to bedrock that is less than 20 inches (described as shallow or very shallow), (c) an erosion condition that is rated as poor, or (d) a K (erosion potential) factor of greater than 0.32 (BLM 1994). Site-specific information related to the general soil type, thickness, distribution of soils over the affected land, and suitability of topsoil for establishment and maintenance of I-1