1988-04-29_PERMIT FILE - C1981008A (53)

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APPENDIX 9-5-2 (Cont.) Soil Interpretations FOOTNOTES 1 Texture of Control Section: as defined in Soil Taxonomy (pp. 383-386). The textural control section is generally the upper 20 inches or the whole of an argillic horizon; or from 10-40" or bedrock whichever is shallower; or the whole soil if bedrock is 14" deep or less. 2 Depth: refers to the soil profile depth before encountering bedrock or a paralithic contact. Depth Class Inches Very Shallow less than 10 Shallow 10-20 Moderately Deep 20-40 Deep 40-60 Very Deep 60+ 3 Major Rooting Depth: depth to which the majority of plant roots were observed to occur. 4 Internal Drainage: refers to aeration or saturation characteristics within the soil profile. Well drained soils allow water to move through the profile readily but not rapidly, and soil aeration is typically not a problem. Somewhat excessively drained soils allow water to move rapidly through the profile, and are typically droughtly, sandy, and poorly developed. Somewhat poorly drained soils have a wet state relatively high in the profile for a significant length of time to impede most uses, unless artifically drained. Poorly drained soils commonly are wet at or near the surface during a considerable part of the year. 5 Permeability: Permeability is a characteristic of soil which relates to the movement of water through the profile. Permeability criteria are based on the rate at which water moves through the most slowly permeable layer to a depth of 60 inches in a saturated soil profile. C Permeability Class Rate (inches/hour) Typical Soil Texture CD Very Slow less than 0.06 C, SiCL, and SiC CD Slow 0.06-0.2 CL+ a Moderately Slow 0.2-0.6 CL, SiL Moderate 0.6-2.0 L, Vfsl, and SCL Moderately Rapid 2.0-6.0 SL, LS Rapid 6.0-20.0 GLS, S, and G w Very Rapid More than 20 G Co