2012-10-29_PERMIT FILE - M2012045 (6)

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EXHIBIT "I" 6.4.9 Soils Information: Soil types (Map Unit Symbols refer to symbols on Soils Map in Exhibit "C ") on the site are: Map Unit: Ap — Apishapa silty clay The Apishapa component makes up 90 percent of the map unit. It occurs in the elevation range of 4,300 feet to 4,800 feet. The frost -free period is 145 to 175 days. Slopes are 0 to 2 percent. This component is on flood -plain steps of the Arkansas River. The parent material consists of clayey alluvium. A typical soil profile is 0 to 8 inches silty clay loam and 8 to 60 inches, clay. Runoff is slow and the hazard of erosion is slight. Depth to a root restrictive layer is greater than 80 inches. The natural drainage class is poorly drained. The capacity of the most limiting layer to transmit water is moderately low to moderately high (0.06 to 0.20 in/hr.) The depth to seasonal high water table generally ranges from 12 to 36 inches. The frequency of flooding is occasional while the frequency of ponding is none. The available water capacity is moderate (about 7.5 inches). The maximum content of calcium carbonate is 5 per cent. The sodium adsorption ratio was not given in the data set. Soil pH ranges from to 9.0. It has a high shrink -swell potential. A low to moderate concentration of salts tends to accumulate from irrigation water or from evaporation of the upward- moving capillary water from the seasonal high water table. The surface layer is difficult to cultivate because of the silty clay texture. The native grasses are salt tolerant and include alkali sacaton and inland saltgrass. The land capability classifications are 3W (irrigated) and 6W (non - irrigated). This component is in the R069XY03000 Salt Meadow ecological site description. Map Unit: BK — Bankard sand The Bankard component makes up 90 percent of the map unit. It occurs in the elevation range of 4,300 feet to 5,100 feet. The frost -free period is 145 to 175 days. Slopes are 0 to 2 percent. This component is on flood plain in sandy alluvium. A typical soil profile is 0 to 4 inches sand and 4 to 26 inches stratified loamy sand, sand, and sandy loam. Permeability is rapid, runoff is slow and the hazard of soil blowing is high. Depth to a root restrictive layer is greater than 80 inches. The natural drainage class is somewhat excessively drained. The capacity of the most limiting layer to transmit water is high to very high (5.95 to 19.98 in/hr.) The depth to seasonal high water table is more than 80 inches. The frequency of flooding is frequent while the frequency of ponding is none. The available water capacity is low (about 4.7 inches). The maximum content of calcium carbonate is 10 per cent. The sodium adsorption ratio was not given in the data set. Soil pH ranges from to 8.4. It has a low shrink -swell potential. These soils are moderately alkaline. The native grasses are mainly plains grasses and include alkali wheatgrass and saltgrass. The land capability classifications are 4W (irrigated) and 6W (non - irrigated). This component is in the R069XY031 CO Sandy Bottomland ecological site description. Map Unit: LnA - Limon silty clay loam The Limon silty clay loam component makes up 95 percent of the map unit. It occurs in the elevation range of 4,300 feet to 5,100 feet. The frost -free period is 145 to 175 days. Slopes are 0 to 2 percent. This component is formed on alluvial fans and terraces in clayey alluvium. A typical soil profile is 0 to 4 inches silty clay loam and 4 to 60 inches silty clay. Runoff is medium and the erosion hazard is generally moderate, but can be severe in places. Depth to a root restrictive layer is greater than 80 inches. The natural drainage class is well drained. The capacity of the most limiting layer to transmit water is moderately low to moderately high (0.06 to 0.20 in/hr.) The depth to seasonal high water table is more than 80 inches. The frequency of flooding is occasional while the frequency of ponding is none. The permeability is slow and the available water capacity is high (about 10.3 inches). The sodium adsorption ration is 10.0. The maximum content of calcium carbonate is 10 per cent. The soils are moderately alkaline to strongly alkaline. Soil pH ranges from to 9.0. It has a high shrink -swell potential. The soil is non - saline to slightly saline (2.0 to 8.0 mmhos /cm). The soil is difficult to till