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Section 785.19(c) Continued. Revised 11/20/80 can be correlated from the mine plan area downstream through the adjacent area to the Canadian River. This fact should be expected, since the bedrock source material for the alluvium is similar throughout the reaches of Bush, Williams and Sudduth Draws down- stream from the mine plan area, as shown on Map 6a, Kerr Mine .Area Geology. As shown in the longitudinal sections (Map 40a), the alluvial water table is well below the root zone, all along the reach of the stream valleys of Bush and Williams Draws. The water table in Sudduth Draw is artificially elevated by the impoundments which occur in series along the length of the draw. The water in the few isolated gravel pockets is confined by impermeable clay in the proposed permit area, preventing natural sub-irrigation from occurring. Soil Moisture Measurements Soil moisture, as it affects the ground water availability of the . intermittent stream valleys in the mine plan and adjacent areas, is measured by two methods: direct observation and sampling during the digging of backhoe pits, and indirectly by neutron geophysical instrumentation. Soil moisture in samples taken from backhoe pits are described in this Section under the Sub-heading "Soils". Relative soil moisture content is measured by using a neutron probe access tube, which detects soil moisture in the capillary fringe above the alluvial water table. Moisture in the capillary zone can supply water to the root zone, thus providing sub-irrigation to plants. An increase in relative soil moisture with depth within the root zone indicates capillary action supporting plant growth. Data from neutron probe access tube measurements in the intermit- tent and perennial stream valleys in the mine plan, general and tipple areas is presented in Exhibit 38, Geophysical Soil Moisture Measurement Study. The neutron soil moisture measurements were taken in the late summer 785-20 as