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peak flows during the year were greatest during the spring as a result of snowmelts. The <br />largest event recorded for Red Wash during the inventory period was 240 cfs, which was <br />generated as a result of late winter snowmelt. Due to the nature and intent of crest gage type <br />flow monitoring, it has limited usefulness for identifying water availability criteria necessary <br />for alluvial valley floor interpretation. Therefore, the most useful information supplied by <br />the permittee for AVF purposes is the estimation of average annual streamflow calculated <br />through Grunsky's formula. The amount of water available annually, as estimated through <br />Grunsky's method, indicates that Red Wash further qualifies as a potential alluvial valley <br />floor. <br />In response to requirements for additional information (Stipulation No. 8), the permittee <br />prepared and submitted a report entitled "Red Wash Drainage Basin Alluvial Valley Floor <br />Study" to the Division on July 23, 1983. The emphasis of this report was to provide <br />additional detailed information on the characteristics of the alluvial body and the availability <br />of sufficient water to support agricultural activities. Based on the information contained in <br />the report and information supplied to the Division by the Meeker Office of the Soil <br />Conservation Service regarding regional flood irrigation practices, the Division made a <br />negative alluvial valley floor determination for those portions of Red Wash situated within <br />the Deserado mine permit area. <br />Past findings of the Division regarding the AVF determination for Red Wash and its <br />associated alluvium are as follows: <br />Red Wash Alluvial Valley Floor Determination <br />The Division determined that Red Wash and its associated alluvium meet the geomorphic <br />criteria, but not the irrigation requirements, of an AVF, as outlined in OSM's "Alluvial <br />Valley Floor Guidelines" established pursuant to the Surface Mining Control and <br />Reclamation Act of 1977. <br />Pursuant to Rule 2.06.8(3)(c), the Division finds that there is not sufficient water to support <br />agricultural activities. <br />Scullion Gulch <br />Water Availability Criteria - Artificial Flood Irrigation <br />As with Red Wash, flow events along Scullion Gulch were monitored using a crest stage <br />gage. During the two year inventory period conducted by the permittee, only three runoff <br />events were recorded, the highest event measuring 185 cfs. Again, crest gage data has only <br />limited application of AVF purposes. The mean annual yield estimations provided by the <br />permittee are more applicable for identifying the amount of water that may be expected for <br />Scullion Gulch. The permittees' estimations, derived using Grunsky's formula, indicate that <br />the potential average annual water yield from the Scullion Gulch watershed is 202 acre feet. <br />This corresponds to approximately 0.34 inches of runoff. The amount of water available <br />Deserado Mine 30 September 19, 2008