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4-18 4.3-15. East Salt Creek is incised into the alluvial material, ' approximately ten to fifteen feet. Site facilities are located several feet higher than the banks of East Salt Creek. Proper pad elevations and grading will allow all site runoff to flow to East Salt Creek after treatment in a sedimentation pond. A more detailed discussion of the creek and the 100-year flood- plain is given in Section 4.3.4.3. 4.3.2.2 Fluvial Geomorphic Characteristics East Salt Creek, in the vicinity of the central facilities, has thalweg gradients ranging from over 18 near DScClane Canyon to 0.68 upstream of Munger Canyon road and to over 3.08 below Munger Canyon road. The Howard Canyon quadrangle map shows ex- tensive meandering and oxbow cutoffs above McClane Canyon and below the south boundary of Section 29 (Figure 9.3-15). Between these reaches, the channel banks are much straighter but the thalweg meanders between the banks. There is some evidence of • natural levees being formed in this reach as shown on the topo- graphic mapping. The meander belt width is not as wide as the valley (Simons, 1977). East Salt Creek appears to be regionally graded or poised; that is the stream gradient and channel geometry is such that the incoming sediment load is conveyed by the stream and no general aggradation or degradation occur. This general stability in East Salt Creek is evidenced by the existence of numerous 8 inch to 24 inch diameter cottonwood and willow trees near the thalweg. The stream appears to be locally active, eroding some banks on the outside of the thalweg meander loops during high flows. This process will proceed slowly and may not endanger mine facilities during the life of the mine. 4.3.2.3 Existing Surface Water Rights • East Salt Creek is located in Former Water District 72, Division V. A table of all surface water rights on East Salt Creek was