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Ll <br />Tssor~t <br />' SOILS INFORMATION EXHIBIT I <br />' The soils in the 108 acre permit area consist of shallow, moderately well drained soils <br />formed in cobbly, clayey alluvium, or outwash on fans and terraces. The north-central <br />part of the site has been stripped of soil by a pervious mining operation and consists of <br />unvegetated weathered Pierre shale. <br />' The natural soils generally exhibit a profile development to a depth of approximately 60 <br />inches, dependant on source and mode of deposition. The A horizons are 3 to 6 inches <br />' of dark grayish brown to dark brown very cobbly clay loam to very cobbly sandy loam. <br />The B horizons are characterized by a significant increase in clays, making them argillic <br />' horizons. The C horizons are up to 40 inches of dark yellow-brown to light gray very <br />cobbly sandy loam to very gravelly sandy loam. <br />t Source materials are quaternary glacial outwash alluvial deposits derived from nearby <br />crystalline; and sedimentary complexes. Weathering of the deposited alluvium has <br />' produced cobbly, loamy soil. Weathered shale bedrock also acts as a source material for <br />some of tl~e soil units mapped in this area. <br />The proposed mine site is located in gently rolling terrain, locally incised by drainages. <br />Vegetation consists of grasses and forbes, with the area around the unreclaimed mine <br />being used for grazing and some wildlife habitat. <br />' Specific soil units <br />Six specific soil units are mapped on and adjacent to the proposed mining site. These <br />units are described in some detail below. <br />1 Weathered shale -- This unit consists of gray to dark gray weathered shale exposed by <br />previous unreclaimed mining operations. The weathered zone in the shale is from zero <br />' to 10 feet thick. Available water capacity is ]ow and runoff is rapid with severe water <br />erosion hacard. <br />-33- <br /> <br />