2013-09-18_PERMIT FILE - M2013064 (9)

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Custom Soil Resource Report Taxonomy" (Soil Survey Staff, 1999) and "Keys to Soil Taxonomy" (Soil Survey Staff, 2006) and in the "Soil Survey Manual' (Soil Survey Division Staff, 1993). If soils are wet enough for a long enough period of time to be considered hydric, they should exhibit certain properties that can be easily observed in the field. These visible properties are indicators of hydric soils. The indicators used to make onsite determinations of hydric soils are specified in "Field Indicators of Hydric Soils in the United States" (Hurt and Vasilas, 2006). Hydric soils are identified by examining and describing the soil to a depth of about 20 inches. This depth may be greater if determination of an appropriate indicator so requires. It is always recommended that soils be excavated and described to the depth necessary for an understanding of the redoximorphic processes. Then, using the completed soil descriptions, soil scientists can compare the soil features required by each indicator and specify which indicators have been matched with the conditions observed in the soil. The soil can be identified as a hydric soil if at least one of the approved indicators is present. Map units that are dominantly made up of hydric soils may have small areas, or inclusions, of nonhydric soils in the higher positions on the landform, and map units dominantly made up of nonhydric soils may have inclusions of hydric soils in the lower positions on the landform. The criteria for hydric soils are represented by codes in the table (for example, 2133). Definitions for the codes are as follows: 1. All Histels except for Folistels, and Histosols except for Folists. 2. Soils in Aquic suborders, great groups, or subgroups, Albolls suborder, Historthels great group, Histoturbels great group, or Andic, Cumulic, Pachic, or Vitrandic subgroups that: A. are somewhat poorly drained and have a water table at the surface (0.0 feet) during the growing season, or B. are poorly drained or very poorly drained and have either: i. a water table at the surface (0.0 feet) during the growing season if textures are coarse sand, sand, or fine sand in all layers within a depth of 20 inches, or ii. a water table at a depth of 0.5 foot or less during the growing season if saturated hydraulic conductivity (Ksat) is equal to or greater than 6.0 in/ hr in all layers within a depth of 20 inches, or iii. a water table at a depth of 1.0 foot or less during the growing season if saturated hydraulic conductivity (Ksat) is less than 6.0 in /hr in any layer within a depth of 20 inches. 3. Soils that are frequently ponded for long or very long duration during the growing season. 4. Soils that are frequently flooded for long or very long duration during the growing season. References: Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of wetlands and deep -water habitats of the United States. U.S. Fish and Wildlife Service FWS /OBS- 79/31. Federal Register. September 18, 2002. Hydric soils of the United States. Federal Register. July 13, 1994. Changes in hydric soils of the United States. 46