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degradation in the stream/alluvial aquifer system would not be sufficient to cause material damage to the waters that 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 having the capacity to support subirrigated and flood irrigated agricultural activities. The AVF has been under-mined by panels 5, 6 and 7 in the Southwest Mining District and panels 13 through 18 in the Northern Mining District. This under-mining did not dewater the stream/alluvial system. Also, as discussed previously, no material damage would result from changes in the quality of 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 operation. Fish Creek continues to be monitored upstream and downstream from the under-mined azea, as required in the approved plan. Trout Creek The boundaries of the Trout Creek alluvial valley floor which would potentially be affected by previously approved operations, and perhaps remotely by PR-07's proposed operation, to which these findings apply include irrigated pasture 8S, which encompasses the Middle Creek/Trout Creek Confluence, and all alluvial deposits downstream on Trout Creek to its confluence with the Yampa River, including irrigated pastures 7, 8N, 9, 10, 11, 12E, 12W, 14, 15S, and 15N, as depicted on Map No. 1 of Exhibit 42 of the PAP. Alluvial deposits on Trout Creek meet alluvial valley floor criteria based on extensive acreage of flood imgated hayland, potential for flood irrigation and a presumed capability to support subimgated vegetation. Flood irrigated hayland and vegetation sample locations are depicted on Map No. 1. Irrigated hayland is the predominant land use on the Trout Creek AVF and the dominant species are Kentucky bluegrass, Smooth brome and Timothy. Based on the extent of existing flood irrigated farmland, and lack of specific information regarding extent or use of subirrigated alluvium, the Division finds that the Trout Creek alluvial valley floor is significant to farming. The required findings are set forth below. The proposed mining operations would not interrupt, discontinue or preclude farming on the alluvial valley floor. Mining activity would not directly impact any portion of the Trout Creek AVF. Any impacts would be indirect, as a result of discharge of affected water into Foidel Creek and Fish Creek. Fish Creek is tributary to Trout Creek, and Foidel Creek is tributary to Middle Creek, which is tributary to Trout Creek. Indirect impacts are addressed under No. 2 below. 2. The proposed mining operations would not cause material damage to the quantity or quality of surface and ground water that supply the alluvial valley floor. 35