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The applicant has mapped unconsolidated streamlaid deposits on terraces of the Colorado River approximately 'fz miles south of the 5-year permit area and along West Elk Creek approximately 2 miles to the northeast of the permit area. A narrow strip of alluvium has also been identified along the Harvey Gap Dtainage in the permit area. Unnamed ephemeral channels draining the Gtand Hogback in the permit and adjacent azea contain very limited alluvial deposits and are too steep, rocky and narrow for agricultural use or alluvial valley floor consideration. The alluvial valley floor potential for the three major drainages in the permit and adjacent area is assessed below. 1. Harvey Gap Drainage The applicant has indicated that a narrow band of alluvium exists along Harvey Gap Drainage in the permit and adjacent area. As such, portions of the Harvey Gap Drainage from Gtass Valley Reservoir downstream approximately 1 mile may meet the geomorphic criteria of an alluvial valley floor. However, infotmation in the application documents that the narrow valley width and steep side slopes would effectively preclude flood irrigation. The width of alluvial material is such that, on the 1:2ft,000 scale map, the unconsolidated streamlaid deposits could not be delineated. No continuous body of alluvium of at least 50 feet in width and 10 acres in extent occurs along Harvey Gap. Vegetation information in the application is sufficient to document an absence of subirrigation, with the exception of scattered cottonwood trees immediately adjacent to the stream channel. The dominant vegetation type along the valley bottom and sideslopes is big sagebrush/cheatgrass, which is not indicative of subirrigadon. The stream channel through the permit and adjacent azea has down cut through the alluvium to a depth of over 60 feet, which would effectively preclude the occurrence of a neaz-surface ground water table. Based on negative determinations regarding flood irrigation potential and subirrigation, Harvey Gap Drainage from Grass Valley Reservoir downstream approximately 1 mile (to where the valley broadens out and meets the terraces of the Colorado River) is determined not to be an alluvial valley floor (see Figure 1, Permit Application). 2. Colorado River A large azea (all or portions of six sections) of unconsolidated streamlaid deposits has been identified within 2'fi miles of the southern boundary of the permit area, to the north of the Colorado River. The origin of the deposits (fan or terrace) is not identified by the applicant. However, the applicant has concluded that, due to widespread flood irrigation on the deposits, the entire area is a probable alluvial valley floor. Irrigation water 18