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-15- No information has been provided concerning the significance of the alluvial valley floor to farming. Therefore, the Division must proceed by assuming that the Fish Creek alluvia] valley floor is significant to fanning and by making all three alluvial valley floor findings. 1) The proposed mining operations would not interrupt, discontinue, or preclude fanning on the alluvial valley floor, because no mining activities would take place within or beneath the alluvial valley floor itself. 2) The proposed mining operations would not cause material damage to the quantity and quality of surface and ground water that supply the alluvial valley floor. Surface flows from the area undermined by the mining operation would not be affected. The underground workings would intercept some of the ground water currently discharging to the stream/alluvial aquifer system. The applicant has estimated that the mine would intercept 98 acre-feet/year of the water currently discharging to the stream/alluvial aquifer system. This represents a continuous discharge of 0.14 cfs that would be intercepted by the mine. Fish Creek is a perennial stream with a base flaw rate of 3 cfs (p. 2.04-20). Discharge in the alluvial aquifer would add to this stream flow. A loss of 0.14 cfs from the stream/alluvial aquifer system would not cause material damage to quantity of water that supplies the AVF. Following mining and reclamation, the mine workings would fill with ground water and water passing through the mine workings would again discharge to the stream/alluvial aquifer system. This water would be expected to have a deyraded water quality (3200 mg/1 TDS at the source), but concentrations would decrease as the affected water flows to the discharge area. The ground water discharge would be further diluted by flow in the stream/alluvial aquifer system. Because of the low flows involved (U. 14 cfs), water quality degradation in the stream/alluvial aquifer system would not be sufficient to cause material damage to the waters which supply the alluvial valley floor. 3) The proposed operation would preserve, throughout the mining operation, the essential hydrologic functions of the alluvial valley floor. The essential hydrologic functions of the Fish Creek alluvial valley floor have been identified as the capacity to support subirrigated and flood-irrigated agricultural activities. Since no mining activities would occur within or beneath the alluvial valley floor and since no significant change would occur in the surface and ground water that supply the alluvial valley floor, the essential hydrologic functions of the alluvial valley floor would not be affected by the proposed operations.