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} 4-6 4.1.3.4 Water Availability 4.1.3.4.1 East Salt Creek Valley According to pertinent SMCRA regulations, an alluvial valley floor is defined as having water sufficient for sub-irriga- tion or flood irrigation. There is evidence that the a11u- vium of the East Salt Creek complies with these conditions. Part of the valley below the McClane Canyon has tradition- a11y been irrigated with a system of diversion ditches, con- tour ditches and graded borders. The irrigated portion ex- tends from the irrigation dam to Munger Canyon with a sys- tem of diversion ditches, contour ditches and graded borders. It is probable that parts below Munger Canyon were irrigated in the past with several areas in the lowest part of the valley being irrigated at present. • 4.1.3.4.2 Side Valleys Based upon the results of office and field studies, it is evident that the water availability criteria necessary for the inclusion of areas as Alluvial Valley Floors precludes such inclusion of the side valleys that are to be impacted by the operations proposed in this revision. The streams ass- ociated with each of the side valleys are ephemeral only, and would not sustain flood or ditch irrigation agricultural act- ivities. The conditions for sub-irrigation are unfavorable as documented in monitoring results and as can be seen through determinations of past usage. Such documentation includes the measurement in monitoring well MW-3 located in the lower part of Munger Canyon (See Munger Canyon, C-020-81, and Figure 4.1-15 of this submittal). This monitoring well is forty feet deep and no groundwater was detected in the well. The measure- ment was performed in April, 1981 during a period of high pre- cipitation and snowmelt. A depth to groundwater of more than forty feet reasonably eliminates any possibility of effective subirrigation. Four test pits excavated in these valleys (Test Pits TP-1, TP-2 and TP-3 in Munger Canyon and Test Pit TP-5 in McClane Revised: b/eja4