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

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• Volume III, Tab 7 shale chips, dark grayish brown (10YR 4/2) moist; massive structure; hard, firm, sticky and plastic consistence; slightly effervescent; from lab data: pH=6.7 (neutral), EC=0.4 (nonsaline), SAR=1.4 (nonsodic), OM=2.9%; gradual wavy boundary. C2k horizon - 30 to 46 inches; pale brown (10YR 6.3) clay with less than 5% small shale chips, brown (10YR 5/3) moist; massive structure; very hard, very firm, sticky and plastic consistence; strongly effervescent; from lab data: pH=7.6 (slightly alkaline), EC=0.4 (nonsaline), SAR=3.0 (slightly sodic), OM=3.4%; gradual wavy boundary. Mancos Clay Loam (Map Unit 4) Soil Suitability and Recommended Salvage Depth: Topsoil 16"/Subsoil 14" Although Mancos clay loam is both nonsaline and nonsodic to slightly sodic, it was not recommended for salvage in the 1995 soil survey of the main Bowie No. 2 Mine "due to the very heavy texture of the soil" (Champion, 1995). Clay percent for the 1995 Mancos soil was 46% as determined by Grand Junction Laboratories. Clay percent for the Mancos soil, as determined by CSU in 2006, was 33% for the 0 to 5" depth, 47% for the 5 to 16" depth, 48% for the 16 to 30" depth, and 50% for the 30 to 46" depth. Clay content for Mancos sample site "S3" weight-averages 45.1 % for the upper 30 inches of the Mancos soil profile. All other soil parameters are entirely "suitable" (WDEQ, 1996). The • soil has a relatively high amount of organic matter content which is good. Although Mancos clay loam has an average of 45 percent clay for the upper 30 inches, the soil can be recommended for salvage especially because it occupies only a small area and will not contribute significantly to the salvaged topsoil volume. The upper 16 inches of Mancos clay loam is recommended for salvage as Topsoil, and the underlying 14 inches as Subsoil. Clay content increases to 50 percent or more below about 30 inches in depth and is considered too high to recommend for salvage. 2.4 Map Unit 5: Steep drainage stony sandy clay loam, a typic Torriorthent Steep drainage stony sandy clay loam (Map Unit 5) is mapped on three steep drainage channels that traverse the Gob Pile study area from northwest to southeast. Map Unit 5 includes the actual drainage channels as well as the steep sideslopes. The drainages are incised due to the steep terrain and previous downcutting. The main drainage channel on the east side of the Gob Pile study area also contains three very narrow stretches of mapped jurisdictional wetlands (see Gob Pile vegetation map). The dominant soil on the steep drainage sideslopes is the Woodlands stony clay loam which was described and sampled at two representative sites in Map Unit 1. The soil is not different in Map Unit 5 although it is located on very steep sideslopes, with slopes exceeding 40 percent. Woodlands stony sandy clay loam was not sampled in Map Unit 5 and is not recommended for salvage due to the steep slopes and included small areas of wetlands. • 10 Exhibit 7 - 2007 Soil Survey Report