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Section 785.19 (c) Continued. <br /> <br />and Williams Draws, northeast of the permit area, and the reach of <br />Sudduth Draw in and downstream from the mine plan area are Girardot <br />silty clay loam (53AC on Map 25, Kerr Mine Area Soils). The reach- <br />es of Bush and Williams Draws in the mine plan area are Spicerton <br />sandy loam (X31AC on Map 25, Kerr Mine Area Soils). All of these <br />areas were examined for the following observable characteristics of <br />subirrigation: 1) increasing soil moisture from a portion of the <br />rooting zone down to the water table due to capillary action, and <br />2) mottling of the soils in the root zones. <br />Regarding the first characteristic, moisture status in general is <br />described as dry, slightly moist, moist, and wet at the time <br />examined according to the USDA - SCS "Definitions and Abbreviations <br />for Soil Descriptions". Documentation of increasing moisture with <br />increasing depth was not noted. There was no observable increase <br />. in soil moisture from a portion of the rooting zone to the water <br />table due to capillary action with respect to any of the draws. <br />One probable reason for this is that below the clayey B horizons in <br />much of the area of all three draws are deposits of sand and gravel <br />where the water table is found. These areas (1) B horizon, and 2) <br />sand and gravel) can be described as having strongly contrasting <br />particle-size classes, a feature which effectively prevents capil- <br />lary action from the sand and gravel layer upward through the <br />clayey B horizon, which contains the root zone. In general, in- <br />creasing soil moisture from a portion of the rooting zone down to <br />the water table due to capillary action was not evident in any of <br />the draws from field observations. This is one of the two charac- <br />teristics that should be observable in a subirrigated area. <br />The second soil-related criteria is soil mottling within the root <br />zone. If the soil is periodically wet or is drained, there should <br />be some mottles of high chrome that were caused by segregation of <br />iron or some reddish, very dark, soft accumulations of iron and <br />785-13 <br />