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Custom Soil Resource Report <br />Soil Qualities and Features <br />This folder contains tabular reports that present various soil qualities and features. <br />The reports (tables) include all selected map units and components for each map unit. <br />Soil qualities are behavior and performance attributes that are not directly measured, <br />but are inferred from observations of dynamic conditions and from soil properties. <br />Example soil qualities include natural drainage, and frost action. Soil features are <br />attributes that are not directly part of the soil. Example soil features include slope and <br />depth to restrictive layer. These features can greatly impact the use and management <br />of the soil. <br />Soil Features (J&amp;J Stone Pit #1) <br />This table gives estimates of various soil features. The estimates are used in land use <br />planning that involves engineering considerations. <br />A restrictive layer is a nearly continuous layer that has one or more physical, chemical, <br />or thermal properties that significantly impede the movement of water and air through <br />the soil or that restrict roots or otherwise provide an unfavorable root environment. <br />Examples are bedrock, cemented layers, dense layers, and frozen layers. The table <br />indicates the hardness and thickness of the restrictive layer, both of which significantly <br />affect the ease of excavation. Depth to top is the vertical distance from the soil surface <br />to the upper boundary of the restrictive layer. <br />Subsidence is the settlement of organic soils or of saturated mineral soils of very low <br />density. Subsidence generally results from either desiccation and shrinkage, or <br />oxidation of organic material, or both, following drainage. Subsidence takes place <br />gradually, usually over a period of several years. The table shows the expected initial <br />subsidence, which usually is a result of drainage, and total subsidence, which results <br />from a combination of factors. <br />Potential for frost action is the likelihood of upward or lateral expansion of the soil <br />caused by the formation of segregated ice lenses (frost heave) and the subsequent <br />collapse of the soil and loss of strength on thawing. Frost action occurs when moisture <br />moves into the freezing zone of the soil. Temperature, texture, density, saturated <br />hydraulic conductivity (Ksat), content of organic matter, and depth to the water table <br />are the most important factors considered in evaluating the potential for frost action. <br />It is assumed that the soil is not insulated by vegetation or snow and is not artificially <br />drained. Silty and highly structured, clayey soils that have a high water table in winter <br />are the most susceptible to frost action. Well drained, very gravelly, or very sandy soils <br />are the least susceptible. Frost heave and low soil strength during thawing cause <br />damage to pavements and other rigid structures. <br />Risk of corrosion pertains to potential soil-induced electrochemical or chemical action <br />that corrodes or weakens uncoated steel or concrete. The rate of corrosion of <br />uncoated steel is related to such factors as soil moisture, particle-size distribution, <br />acidity, and electrical conductivity of the soil. The rate of corrosion of concrete is based <br />mainly on the sulfate and sodium content, texture, moisture content, and acidity of the <br />soil. Special site examination and design may be needed if the combination of factors <br />results in a severe hazard of corrosion. The steel or concrete in installations that <br />intersect soil boundaries or soil layers is more susceptible to corrosion than the steel <br />18