2005-07-19_GENERAL DOCUMENTS - C1981018

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1970), the salinity hazard of such water could be rated "very high". Geomorphic Characteristics Scullion Gulch is an ephemeral stream that crosses the lower southwest portion of the permit azea, draining to the White River. The confluence of Scullion Gulch and the White River is also within the permit area. Scullion Gulch receives drainage from the southwestern and south-central portions of the permit area, as well as from adjacent lands to the west. Scullion Gulch is approximately one-tenth the size of Red Wash, draining an area of 11.7 square miles. Approximately half of the drainage azea exists within the permit azea. Map 102 identifies the alluvial deposits mapped by the permittee along Scullion Gulch. The deposits typically range between 50 and Z00 feet in width, with a depth of about 15 feet. The deposits were mapped by the permittee to a point approximately 1/4 mile upstream from the permit azea, where they become discontinuous. At this location, the deposits do not appeaz to extend any further up the drainage. The permittee again did not quantify the amount of land azea occupied by the deposits; however, based on Map 102 it appears the alluvial deposits occupy a few hundred acres. Scullion Gulch is incised into both the upper sandstone facies and a portion of the middle sandstone facies, both of which are waterbearing rock units. Five stock-watering ponds exist along Scullion Gulch. As in Red Wash, the ponds serve to retain water for stock purposes until it is lost to seepage or evaporation. They do not hold water year round. Based on the width and azeal extent of alluvial deposits along Scullion Gulch, the drainage generally meets the geomorphic criteria and therefore qualifies for further consideration as an alluvial valley floor. Water Availability Criteria -Artificial Flood Irrigation As with Red Wash, flow events along Scullion Gulch were monitored using a crest stage gage. During the two year inventory period conducted by the permittee, only three runoff events were recorded, the highest event measuring 185 cfs. Again, however, crest-gage data has only limited application for AVF purposes. The mean annual yield estimations provided by the permittee aze more applicable for identifying the amount of water that may be expected for Scullion Gulch. The permittees' estimations, derived using Grunsky's formula, indicate that the potential average annual water yield from the Scullion Gulch watershed is 202 acre feet. This corresponds to approximately 0.34 inches of runoff. The amount of water available annually, as estimated through this method, indicates that Scullion Gulch warrants further consideration as a potential alluvial valley floor. Subirrigation As with Red Wash, the presence of subimgation along Scullion Gulch was investigated by 4F