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04021 <br />Exhibit I -Soils Information <br />Banks and Gesso, LLC <br />Please refer to Exhibit C-2: Pre-Mining Map (Natural Features) for mapped USDA soils. <br />Five soil types exist within the proposed permit area. These types are Altvan Loam, <br />Aquolls and Agents (Gravelly Substratum), Dacono Clay Loam and Otero Sandy Loam. <br />Altvan Loam is found in the majority of the mining site. This soil is found on 0 to 1 <br />percent slopes, and is deep and well drained. The surface layer is grayish brown loam <br />about 10 inches thick. The subsurface layer is brown and light yellowish brown clay <br />loam and sand clay loam about 15 inches thick. The bedrock layer is calcareous loamy <br />sand about 6 inches thick over gravelly sand. Permeability and available water capacity <br />are moderate. The effective rooting depth is 20 to 40 inches. Surface runoff is slow and <br />the erosion hazard is low (USDA, SCS). <br />Aquolls and Aquents (Gravelly Substratum) soils are found in the east-central portion of <br />the permit area and on bottom lands and flood plains of all the major streams in the <br />area. Aquolls, which have a dark colored surface layer, make up about 60 percent of the <br />unit, while, Aquents, which have a colored surface layer, make up about 35 percent. <br />These soils are deep and poorly drained that formed in recent alluvium. Aquents and <br />Aquolls soils tend to have a mottled, mildly alkaline to moderately alkaline loamy or <br />clayey surface layer and subsurface layer. The underlying material is sand or sand and <br />gravel within 48 inches. In places, they have a gleyed layer in the underlying material. <br />Most of the acreage is subject to flooding. The water table is at or near the surface early <br />in spring and recedes to as deep as 48 inches in fall in some years. The dominant <br />native grasses are alkali sacaton, switchgrass, and western wheatgrass. Saltgrass, <br />sedge, rush, and alkali bluegrass are also prominent. These soils have good potential <br />as a source of sand and gravel (USDA, SCS). <br />Dacono Clay Loam can be found along the southern edge of the site and occurs on 0 to <br />1 and 1 to 3 percent slopes. This deep, well drained soil is formed in mixed alluvium. <br />The surface layer of this soil is grayish brown clay loam about 12 inches thick. The <br />subsoil is grayish brown clay loam about 15 inches thick. The underlying material is very <br />gravelly sand. Permeability is moderately slow and water capacity is moderate. The <br />effective rooting depth is 20 to 40 inches. Surface runoff is slow for slopes of 0 to 1 <br />percent and medium for slopes of 1 to 3 percent, and the erosion hazard for both is low. <br />This soil is used almost entirely for irrigated crops (furrow irrigation), but all methods of <br />irrigation are suitable. Above the sand and gravel layer, the soil has moderate to high <br />shrink swell, low strength, and moderately slow permeability. These features create <br />problems in dwelling and road construction. Excessive permeability is the underlying <br />layer can cause contamination of ground water supply from septic tank leach fields. The <br />dominant native grasses are western wheatgrass and blue grams, and buffalograss is <br />present (USDA, SCS). <br />Otero Sandy Loam can be found in the extreme northwest corner of the site. This deep, <br />well-drained soil can be found at 3 to 5 percent slopes and is formed in mixed outwash <br />and eolian deposits. The surface layer typically consists of a brown sandy loam about <br />10 inches thick, and the underlying material to a depth of 60 inches is pale brown <br />calcareous fine sandy loam. Permeability is rapid and available water capacity is <br />moderate. The effective rooting depth is 60 inches or more. Surface runoff is medium, <br />and the erosion hazard is low. This soil is used almost entirely for irrigated crops. The <br />Asphalt Paving Company October 11, 2005 <br />Wattenberg West Sand and Gravel Mine Page 19 <br />