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on Map 1 as have been disturbed by previous unrelated mining activities and by construction of water treatment facilities and should not be identified as alluvial valley floors.) The areas designated as CRT (Colorado River Terrace), as well.as, the lower terraces and floodplain along the Colorado River, are determined to be alluvial valley floors. The areas identified as CRT consists of unconsolidated streamlaid deposits that are currently flood irrigated. The lower terraces and floodplain are flood irrigated in several areas (Map 2), and may be subirrigated in places. Significance to Agriculture Since no agricultural information has been provided from any of the areas designated as alluvial valley floors, all the areas will be assumed to be agriculturally significant, and all three alluvial valley floor findings will be made. Rapid Creek Alluvial Valley Floor - Findings 1. The proposed surface coal mining operations would not interrupt, discontinue, or preclude farming on an alluvial valley floor. The area designated as alluvial valley floor lies outside of the permit area,downstream from the proposed operations. As a result, there would be no surface disturbance within the AVF, and the area would not be undermined. 2. The proposed surface coal mining operations would not materially damage the quantity and quality of water in surface and underground water systems that supply these alluvial valley floors or portions of alluvial valley floors. The Rapid Creek alluvial valley floor receives the water supply from the Rapid Creek/Cottonwood Creek stream system. Since no surface facilities are located within this system, and no disturbed runoff or mine water would be discharge to Rapid Creek or Cottonwood Creek, the proposed operations will not affect water quality. The Division has estimated that stream flow depletion in the absence of flow through fractures, either natural or as a result of subsidence, would be less than 0.003 cfs. Such a minor loss would not be detectable. The applicant has proposed a limited extraction mine plan beneath the streams, and subsidence effects would not be expected in these areas. No major natural fractures have been identified in the permit application. Minor fractures are undoubtedly present, but may not be open to the passage of ground water. The required surface water and mine water monitoring will detect any unanticipated change in the existing hydrologic system. 3. Surface coal mining and reclamation operations would be conducted to preserve, throughout the mining and reclamation process, the essential hydrologic functions of the alluvial valley floor. _Zq_