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-28- Alkali Creek Only a small portion of the proposed permit area is within the Alkali Creek drainage basin. The permit area within this drainage is limited to approximately three miles of light use road to monitoring well SK 3.75. The applicant submitted very little AVF information on this drainage. Therefore, the Division must conservatively assume that the unconsolidated streamlaid deposits in Alkali Creek comprise a significant alluvial valley floor. Alkali Creek Findings 1) None of the light use road is located within the alluvial valley floor. Based on that fact, the Division finds that the proposed operation will not interrupt, discontinue, or preclude farming on the alluvial valley floor. 2) Surface waters which supply the alluvial valley floor are derived from the Alkali Creek drainage and Garfield Creek. Water is diverted from the Garfield Creek drainage through the Sykes and Alford trans-basin ditch into Porter Reservoir. The water in Porter Reservoir is then directed to Alkali Creek through the Roderick ditch as needed. Other small reservoirs are located in the lower reaches of Alkali Creek. The only anticipated effect to surface water in the Alkali Creek drainage is a slight increase in suspended solids. The light use road construction techniques are in conformance with all applicable design standards, therefore, the slight increase in suspended solids should have an insignificant effect on the quality of water in Alkali Creek. There should be no effect on the quantity of water in the Alkali Creek drainage basin due to the light use road. The roads will be constructed with adequate cross-drains capable of passing the peak flow from a 10-year 24-hour precipitation event. In addition, there will be no detention structures associated with this road. Based on the above discussion, the Division finds that the proposed operation will not materially damage the quantity and quality of water in the surface and underground water systems that supply the alluvial valley floor or portions of the alluvial valley floor. 3) The proposed mining operation will not physically disturb the alluvial valley floor. As discussed above, there will be no effects on the quantity and quality of water supplied to the AVF. Therefore, the Division finds that the proposed mining operations will be conducted to preserve, throughout the mining and reclamation process, the essential hydrologic functions of the alluvial valley floor.