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Alluvial Vallev Floors The main concern the Division has is that the mapping and detailed chazacterization submitted in the preliminary investigation report terminated at the lower permit boundary on both Jubb Creek and Collom Gulch. The Division thinks it is important that the reconnaissance investigation be extended downstream to Morgan Gulch (for Collom Creek) and Milk Creek (for Jubb Creek). Based on review of the preliminary report and the site visit on Oct. 4`" and 5'~, the Division agrees that there aze probably not alluvial valley floors within the proposed permit azea. One azea of particulaz interest is the valley of Collom Gulch downstream of Section 26 (downstream of proposed disturbance but within the proposed permit boundary). This is an azea where the valley widens out and there is evidence of old "improvements" including remnant crested wheatgrass, a small grove of elm trees, some fenced enclosures and a possible abandoned irrigation ditch (now overgrown and indistinct in some azeas). Farther downstream (north of the main east-west county road) the valleys of Collom Creek and Jubb Creek widen out more. Lower Collom Creek was identified as a potential AVF in the June 1985 OSM Reconnaissance Mapping document, based on the presence of surface irrigation in some azeas and the potential for such irrigation in other azeas (there is an azea approximately one mile north of the county road on Collom Gulch that likely corresponds to the azea designated flood irrigated on the OSM mapping). There was a recently plowed agricultural field in this wide valley location. Colowyo indicated that it was dryland wheat fallow land. That may be the case, but there was cleazly an irrigation ditch along the road. If the field is not being irrigated under present agricultural management, it appeazs that it was irrigated in the not too distant past. This was a mile or more upstream from the Morgan Gulch confluence. Downstream from the cropland there was a relatively broad wetland extending along the drainage, apparently dominated by native wetland species. There was no indication that the subimgated wetland azeas had been hayed or otherwise managed for enhanced agricultural production. Reconnaissance investigations should be extended downstream on both Collom Creek and Jubb Creek. Detailed information regarding the present management and management history of the cropland on Collom Creek (and Jubb Creek, if present) including irrigation practices, diversion points, etc will need to be provided. Ve¢etation As with the soils baseline, the Division has been in close contact with the operator with regazds to the vegetation baseline sampling. During the baseline study, six different communities were noted. These include sagebrush (40%), mountain shrub (27%}, juniper scrub (17%), grassland (7%), bottomland (5%) and aspen (2%). There are also some wetlands that aze along every streambed and spring and seep. Colowyo is planning on using tazgeted reference areas, which is a fairly new concept. The Division will have to evaluate these on a case-by-case basis.