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' EXHIBIT I- Soils Information <br /> ' The soils in the permit area are shown on Figure J-1. They consist of shallow, moderately well drained <br /> soils formed in cobbly, clayey alluvium, or outwash on fans and terraces. The north-central part of the <br /> mine site has been stripped of soil by a pervious mining operation and consists of unvegetated weathered <br /> Pierre Shale. <br /> ' The natural soils generally exhibit a profile development to a depth of approximately 60 inches,dependant <br /> on source and mode of deposition. The A horizons are three to six inches of dark grayish brown to dark <br /> ' brown very cobbly clay loam to very cobbly sandy loam. The B horizons are characterized by a <br /> significant increase in clays, making them argillic horizons. The C horizons are up to 40 inches of dark <br /> yellow-brown to light gray very cobbly sandy loam to very gravelly sandy loam. <br /> ' Source materials are quaternary glacial outwash alluvial deposits derived from nearby crystalline and <br /> sedimentary complexes. Weathering of the deposited alluvium has produced cobbly, loamy soil. <br /> ' Weathered shale bedrock also acts as a source material for some of the soil units mapped in this area. <br /> The existing shale mine and proposed ash backfilling site is located in gently rolling terrain, locally <br /> ' incised by drainages. Vegetation consists of grasses and forbes, with the area around the mine being used <br /> for grazing and some wildlife habitat. <br /> ' Specific Soil Units <br /> Six specific soil units are mapped on and adjacent to the existing mine and proposed ash backfilling site. <br /> ' These units are described in some detail below. <br /> Weathered shale - This unit consists of gray to dark gray weathered shale exposed by previous mining <br /> operations. The weathered zone in the shale is from zero to ten feet thick. Available water capacity is <br /> ' low and runoff is rapid with severe water erosion hazard. <br /> Existing,unreclaimed steep slopes will be reshaped before planting according to an approved reclamation <br /> ' plan. Some areas should be covered with a layer of topsoil. Mulching is essential in establishing good <br /> stands of plantings on steep slopes. Applications of manure and nitrogen and phosphorous rich fertilizers <br /> are needed. <br /> Yoder Variant - Midway Complex. 15 to 60 percent sloes - The Yoder Variant soils are found on <br /> ridges and the Midway soil is on hill slopes. The soils are so intricately intermingled that no attempt was <br /> Imade to map them separately. <br /> Typically, the surface layer in the Yoder Variant is neutral, dark brown gravelly sandy loam about three <br /> I inches thick. The subsoil in the upper five inches is a neutral reddish brown gravelly sandy loam. the <br /> substratum to a depth of 60 inches is neutral, yellowish red very gravelly loamy sand. <br /> I Permeability is moderately rapid and available water capacity is low. The effective rooting depth is 60 <br /> inches or more. Runoff is rapid and water erosion can be severe. Rock fragments make up 15 to 35 <br /> percent of the volume in the solum and 35 to 60 percent in the substratum. <br /> I I - 1 <br /> S B i SERGENCONS T HAUS L KIINS & BECKWITH <br /> I ENGINEERS <br /> PHOENIX•TUCSON•ALBUOUEROUE <br /> f DENVER/LAKEWOOD•SALT LAKE CITY•EL PASO•RENO/SPARKS <br />