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limited in Scullion Gulch. Further evidence of the general lack of subirrigation can be <br /> gleaned from the permittee's surface facilities geotechnical investigation, contained in <br /> Illustration 18 of the permit application. Six exploration holes, sited at the proposed <br /> D-portal area, were drilled within the alluvial body associated with Scullion Gulch. <br /> Although all the holes fully penetrated the alluvium, no evidence of alluvial ground water <br /> was encountered. This information, coupled with the sparse occurrence of deep-rooted <br /> vegetation, generally indicates that subirrigation is of minimal consequence along Scullion <br /> 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 streamlaid <br /> deposits,the availability of supplemental moisture through subirrigation, 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 <br /> White River AVE For the most part, the White River lies outside the permit area. <br /> Mining will not take place beneath the river or its alluvial deposits. The permittee has <br /> adequately demonstrated that bedrock contributions of ground water from the area to be <br /> mined are insignificant in relation to the flows observed in the White River. Flows to the <br /> White River from Red Wash and Scullion Gulch,which may be impacted by mining, are <br /> also 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 <br /> suffer material damage via either of these drainages. <br /> At the time of the original permit issuance, Kenney Reservoir, which presently exists <br /> within the project area, had not yet been filled. As such, the original findings document <br /> for the Deserado Mine contained an assessment of the potential for material damage to <br /> occur to the White River AVF as a result of the permittee's proposed pumping of water <br /> from the AVF for use in the mine. The permittee had demonstrated that the volume of <br /> water removed from the alluvium was insignificant to the flow volumes observed on the <br /> White River even during low flow years, and had concluded that the effects of drawdown <br /> on the alluvial water body would not significantly impact farming due to the exclusive use <br /> of artificial flood irrigation practices in the area rather than natural sub-irrigation. This <br /> was felt to be a reasonable conclusion; however, it was also felt that natural sub-irrigation <br /> might provide additional, supplemental moisture to flood irrigated crops. In view of this, <br /> two stipulations were attached to the permit to provide for ongoing monitoring of the <br /> alluvial body to verify the anticipated drawdowns caused by pumping, and to provide for <br /> the development of a mitigation plan to protect farming operations in the event that <br /> xxxix <br />