2014-05-07_PERMIT FILE - C1996083 (2)

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Volume III, Tab 7 Table 1 (List of Map Units and Affected Area Soil Salvage Summary, Bowie No. 2 Mine Gob Pile) lists the soil map units within the Gob Pile study area, their soil sample location numbers, and summarizes their salvage depths and limitations to deeper salvage. Projected disturbance acreage for each map unit in the affected area, as well as estimated cubic yard volumes of recommended salvageable soil, are contained in the project mine and reclamation plan. The following text is a description of the five map units in the study area and their component soils, as well as an evaluation of their topsoil suitability and recommended salvage depths. The map unit descriptions are presented in alphabetic order, as follows: 2.1 Map Unit 1: Woodlands stony sandy clay loam, a typic Torriorthent 2.2 Map Unit 2: Meadow-Mtn Shrub stony sandy clay loam, a typic Haplargid 2.3 Map Unit 4: Mancos clay loam, part of the Persayo-Chipeta soils 2.4 Map Unit 5: Steep Drainage stony sandy clay loam, a typic Torriorthent 2.5 Map Unit 6: Steep Mountainsides stony sandy clay loam, a typic Torriorthent - Sandstone Rock Outcrop Complex 2.1 Map Unit 1: Woodlands stony sandy clay loam, a typic Torriorthent Map Unit 1 (Woodlands stony sandy clay loam, a typic Torriorthent) is the most extensive soil map unit on the Gob Pile study area. It is mapped on areas identified as "Juniper Woodland" (JW) on the vegetation map. The "Woodlands" soil unit is moderately deep (20 to 40" to bedrock) to deep (40 to 60" or more to bedrock) and well drained. It is both nonsaline and nonsodic and is forming in colluvial slopewash materials deposited from upslope positions. Map Unit 1 is suitable for salvage to a depth of about 30 inches, which is very consistent with the 30-inch average salvage recommendation for Map Unit 1 as stated in the 1995 soil study (Champion, 1995). The "Woodlands" soil has moderate permeability and moderate available water holding capacity. The effective rooting depth is 30 inches or more. Runoff is medium and the water erosion hazard is moderate to severe. In a typical profile, the soil has a stony sandy clay loam surface layer about 2 inches thick. The cambic horizon "Bw1" upper subsoil layer is also a stony sandy clay loam about 6 inches thick (from 2 to 8 inches in depth). The cambic horizon "Bw2" lower subsoil layer is a stony clay loam about 8 to 10 inches in thickness (from 8 to 16, or 8 to 18 inches in depth). Rock fragment content of the upper 18 inches is about 15 to 20% gravel, cobble, and stone size rocks. A substratum "Ck" horizon exists from about 18 to 30 inches in depth. It has stony clay loam to sandy clay loam texture with about 20 to 25% rock fragments. The lower substratum "C" horizon below 30 inches is "skeletal" with greater than 35% rock fragments and very difficult to dig. • 4 Exhibit 7 - 2007 Soil Survey Report