2010-04-16_GENERAL DOCUMENTS - C1981008

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P.3 --T?L 5'--7 5. The soils can be managed so that, in all horizons within a depth of 40 inches (1 meter) or in the root zone if the root zone is deep), during part of each year the conductivity of the saturation extra , is less than 4 mmhos/cm and th exchangeable sodium percentage (ESP) is less than 15; and, 6. The soils are not flooded frequently during the growing season (less often than once in 2 years) ; and, 7. The product of K (erodibility factor) x percent slope is less than 2.0, and the product of 1 (soils erodibility) x C (climatic factor) does not exceed 60; and, 8. The soils have a permeability rate of at least 0.06 inch (0.15 cm) per hour in the upper 20 inches (50 cm) and the mean annual 0 soil temperature at a depth of 20 inches (50 cm) is less than 59 F (150C) the permeability rate 18 not a limiting factor if the mean annual soil temperature is. 59 0 F (15 C)`or higher, and, 9. Less than 10 percent of the surface layer (upper 6 inches) in these soils consists of rock fragments coarser than 3 inches (7.6 cm). The following modifications and/or interpretations of the National Criteria for Prime Farmlands were used in Colorado. The soil must have: 1.. A developed irrigation water supply that is dependable and adequate.to meet moisture, requirements 8 out of 10 years and have 4,:inches or more available. water capacity within a depth of 40 inches 1 meter), or within the root Zone if the root zone is less than 40 inches;2. A growing season of 90 days or 3. No water table or the water table is below a depth of 1.5 feet and drainage is possible; 4. A conductivity of 8 mmhos/crn or less in the upper 40 inches and permeability is greater than .2 inches/hr. (moderately slow or greater) if the slope is less than 2 percent. These soils are considered capable of being managed so that all horizons within a depth of 40 inches (1 meter) or in the root zone (Revised June 2008) Attachment 2.04.9-5-3