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<br /> <br /> <br /> 67 C1981-041 RN7 findings <br />species located on the T2 terrace are deep rooted and do not indicate the general <br />availability of groundwater to agriculturally useful species. The T3 terrace does <br />not have vegetation indicating subirrigation. <br /> <br />Several minor ephemeral streams also drain the permit area. The stream valleys <br />are narrow, steep, and contain very little alluvium. None of these valleys contain <br />deposits meeting the AVF size criteria. <br /> <br />Areas along the Colorado River have been identified as terrace landforms with <br />existing flood irrigation. The lowest terrace is marginally subirrigated, but the <br />upper terraces are not subirrigated. <br /> <br />Based on the above information, two areas of alluvial valley floors can be <br />identified. The two upper terraces (T2 and T3) have been identified as <br />unconsolidated streamlaid deposits, and have sufficient waters to support flood <br />irrigated agricultural activities. (Except, two of the areas designated on Map 1 as <br />have been disturbed by previous unrelated mining activities and by construction <br />of water treatment facilities and should not be identified as alluvial valley floors.) <br />The areas designated as CRT (Colorado River Terrace), as well as the lower <br />terraces and floodplain along the Colorado River, are determined to be alluvial <br />valley floors. The areas identified as CRT consists of unconsolidated streamlaid <br />deposits that are currently flood irrigated. The lower terraces and floodplain are <br />flood irrigated in several areas (Map 2), and may be subirrigated in places. <br /> <br />Significance to Agriculture <br /> <br />Since no agricultural information has been provided from any of the areas <br />designated as alluvial valley floors, all the areas will be assumed to be <br />agriculturally significant, and all three alluvial valley floor findings will be made. <br /> <br />Rapid Creek Alluvial Valley Floor - Findings <br /> <br />1. The proposed surface coal mining operations would not interrupt, discontinue, or <br />preclude farming on an alluvial valley floor (4.24.3(1)). <br /> <br />The area designated as alluvial valley floor lies outside of the permit area, downstream <br />from the proposed operations. As a result, there would be no surface disturbance <br />within the AVF, and the area would not be undermined. <br /> <br /> 2. The proposed surface coal mining operations would not materially damage the <br />quantity and quality of water in surface and groundwater systems that supply these <br />alluvial valley floors or portions of alluvial valley floors (4.24.3(3)). <br /> <br />The Rapid Creek alluvial valley floor receives the water supply from the Rapid <br />Creek/Cottonwood Creek stream system. Since no surface facilities are located within <br />this system, and no disturbed runoff or mine water would be discharge to Rapid Creek