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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 permit issuance, Kenney Reservoir, which presently exists within the <br />project area, had not yet been filled. As such, the original findings document for the <br />Deserado Mine contained an assessment of the potential for material damage to occur to <br />the White River AVF as a result of the permittee's proposed pumping of water from the <br />AVF for use in the mine. The permittee had demonstrated that the volume of water <br />removed from the alluvium was insignificant to the flow volumes observed on the White <br />River even during low flow years, and had concluded that the effects of drawdown on the <br />alluvial water body would not significantly impact farming due to the exclusive use of <br />artificial flood irrigation practices in the area rather than natural sub - irrigation. This was <br />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 />M <br />