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annually, as estimated through this method, indicated that Scullion Gulch warrants further <br />consideration as a potential alluvial valley floor. <br />Sub-irrigation <br />As with Red Wash, the presence of sub-irrigation along Scullion Gulch was investigated by <br />the permittee based on the type of vegetation present along the drainage. The permittee has <br />identified a big sage brush-greasewood community along the entire length of unconsolidated <br />alluvial deposits identified on Map 102, and concludes that water is available to the <br />vegetation "on a limited and sporadic basis". The big sage brush-greasewood community, <br />however, is sparser compared to that community found along Red Wash, indicating the <br />availability of subsurface water is much more limited in Scullion Gulch. Further evidence of <br />the general lack of sub-irrigation can be gleaned from the permittee's surface facilities <br />geotechnical investigation, contained in Illustration 18 of the permit application. Six <br />exploration holes, sited at the proposed "D" portal area, were drilled within the alluvial body <br />associated with Scullion Gulch. Although all the holes fully penetrated the alluvium, no <br />evidence of alluvial groundwater was encountered. This information, coupled with the <br />sparse occurrence of deep-rooted vegetation, generally indicates that sub-irrigation is of <br />minimal consequence along Scullion Gulch. <br />Scullion Gulch Alluvial Valley Floor Determination <br />The Division and OSM concluded that Scullion Gulch is not an alluvial valley floor. <br />White River <br />Alluvial Valley Floor Determination <br />On the basis of available annual water yield, the presence of unconsolidated stream laid <br />deposits, the availability of supplemental moisture through sub-irrigation, and the presence <br />of established irrigated lands, the Division and OSM identify the White River and its <br />associated alluvial deposits as an alluvial valley floor. <br />The permittee has supplied sufficient information to address material damages to the White <br />River AVE The majority of the White River lies outside of the permit area. Mining will not <br />take place beneath the river or its alluvial deposits. The permittee has adequately <br />demonstrated that bedrock contributions of ground water from the area to be mined are <br />insignificant in relation to the flows observed in the White River. Flows to the White River <br />from Red Wash and Scullion Gulch, which may be impacted by mining, are also <br />insignificant in relation to the flows observed in the White River. By minimizing <br />disturbances to Red Wash and Scullion Gulch during mining, the White River will not be <br />subject to material damage via either of these drainages. <br />At the time of permit issuance, Kenney Reservoir, which presently exists in the project area, <br />had not yet been filled. As such, the original findings document for the Deserado Mine <br />contained an assessment of the potential for material damage to occur to the White River <br />Deserado Mine 31 September 19, 2008