2017-02-03_PERMIT FILE - C1980004 (2)

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2.04.9 Soils Resource Information than one to 57.3. Most soils have values less than 5.0 and are rated good to fair. Most subsoils are rated good to fair. The Havre soil, however, is rated poor below 1.5 inches. Electrical conductivity is a measure of soil salinity. Excessive salts restrict plant growth, create problems in establishing vegetation and therefore also influence erosion and the stability of the surface. EC values range from less than one to 27.2 mmhos/cm. Most of the soils have values less than 5.0 mmhos/cm. and are rated good for salinity. The saline phase of the Havre soil is rated fair to poor in the subsoil. Toxic materials such as boron enter the food chain and are toxic to animals that eat the vegetation (USDA, 1978). All soils in the permit area are rated good for boron; no values exceeded 1.0 ppm. Excessively high or low pH causes problems in establishing vegetation and as a result of influences erosion and stability of the surface (USDA, 1978). Most soils have good or fair pH values throughout. The substratum of the alluvial soils and Havre soils have moderately to strongly alkaline pH values. The available water capacity also is important in establishing vegetation. Soils with low available water capacity may require irrigation for establishment of vegetation (USDA, 1978). AWHC was estimated based on field texture and percent coarse fragments (USDA, 1974). Most of the soils are rated good for AWHC. The disturbed land material and the alluvial land soil are rated good and fair, respectively. Some subsoils have fair ratings. The stability of the soil depends upon its erodibility by water and wind and it's strength. Water erodibility is indicated by the K factor; wind erodibility is rated according to the wind erodibility group. K values for soils of the permit area are calculated for Wischmeier's equation of soil erodibility (Wischmier, 1971). Most soils are rated good throughout for water erodibility; the K factor for the Havre soil is fair. The Alluvial land soil is rated poor. Wind erodibility group is based on soil textural class and lime content and rated by SCS criteria (USDA SCS, 1974). The surface layers of most soils are rated good or fair throughout. The roadfill material is rated good. The Alluvial land soil is rated poor. USDA texture influences available water capacity and erodibility by wind or water. Texture also influences soil structure, consistence, water intake rate, runoff, fertility, workability, and trafficability. Potential slippage hazard is related to soil, texture, and although other factors also contribute, the ratings of soil texture represent one important factor (USDA, 1978). Soil textures are rated good to fair for soils in the permit area, but are generally not considered the limiting factors. The alluvial lands soils are too sandy in the substratum and are rated poor below two inches. The textures of the roadfill material are rated fair in both samples. Coarse fragments influence the ease of excavation, stockpiling, respreading, and suitability for the final use of the land. A certain amount of coarse fragments can be PR -02 2.04-47 10/12