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• The upland area terrace topography of the Cottonwood-Rapid Creeks area is <br />represented on the cross-section on Plate II of Appendix 21-3. Flood irrigation <br />analysis for Rapid Creek can be found in Appendix 21-4. There were three <br />. terraces identified along Rapid Creek off the permit area. The T, terrace is too <br />small and irregular to be considered for agricultural activities. The majority of the <br />Tz terrace has a rough surface with large basaltic boulders. The disturbed nature <br />of the valley, due to previous mining operations, makes it unlikely that irrigable <br />lands would ever be developed on this terrace. The T3 terrace has been <br />historically irrigated. Shallow groundwater is not available for subirrigation of <br />agriculturally important species in the Rapid Creek Valley. Mapping of the <br />Cottonwood-Rapid Creeks area showing different types of agricultural lands can <br />be found on Plate I of Appendix 21-3 and Map 1 of Appendix 21-4. <br />The capability of the previously flood irrigated land to be irrigated in the future <br />depends on the following criteria: <br />- The stream-flow water yield is limited to 0.02 cubic feet per second <br />per acre (refer to Appendix 21-5). <br />• - The soils are of high salinity (see Appendix 9-2, Tab Section 9). <br />- The alluvium in the area has a moderate water capacity, <br />approximately 5.0 to 7.5 inches (U.S. Department of Agriculture, <br />1960). <br />- Water quality can be anticipated to be the same as that of the <br />Colorado River. The Colorado River is characterized by high <br />salinity (refer to Table 7-9 in Tab Section 7). <br />The lands within the area are historically undeveloped. Since the late 1800's, <br />and to the present, land use has been wildlife habitat and industrial. After all <br />mining operations cease, the land will be reclaimed to wildlife habitat. <br />21-3 (Rev. 1 /00) <br />