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Mc Jim Sark September 23, 2005 Page 5 of 6 project area, historic cultivation and irrigation has occurred to a notable extent only in larger valley bottoms within the Danforth Hills, such as those of Morgan Gulch and Lower Wilson Creek. Current agricultural production on flood plains and terraces adjacent to Jubb Creek and Collom Gulch occurs only on the largest relatively level aeeas at lower elevations north of the proposed permit area. The local office of the Natural Resource Conservation Service (MRCS) in Craig, Colorado was visited on August 28, 2005 to collect information that could assist in AVF determinations. According to Mr. Paul Billing, Rangeland Management Specialist, the NRCS does not maintain a map of irrigation potential nor does it evaluate the feasibility of developing tracts for irrigation. However, based on Mr. Billing's experience in the area, most tracts even marginally suitable for irrigation were developed more than 40 years ago. Since that time, many of these tracts have reverted to dryland agricultural production and, in some cases, rangeland. New irrigation projects are very rare and do not occur in the topographic positions described as occurring in the proposed Collom permit area. Relative to sprinkler irrigation, flood irrigation was described as being very inefficient and rarely incorporated into the design of new irrigation systems. Valley bottoms unsuitable for sprinkler irrigation are generally used for dryland agriculture or rangeland. Mr. Billing's opinions were offered without the benefit of a site visit. Monitoring of stream flows in [he project area indicates that surface water in sufficient quantity and quality exists for seasonal flood irrigation in some areas (Table 4.1, Water Management Consultants, 2005, Collom Project Pre-Feasibiilry Hydrology Report). However, analysis of the potential economics of developing a flood irrigation system in the area (Dames and Moore,1980; James P. Walsh & Assoc., Inc., 1984) indicated that, based on regional agricultural practices, the cost for such development would be prohibitive given the relatively small area potentially available for flood irrigation. Changes in agricultural economics since this report was completed are even more prohibitive to new development (less return per unit of investment). The majority of the soils and topography within the areas delineated in Figure 1 could support irrigation. It is likely that spring runoff in the area could be captured by structures and delivered to the alluvial deposits for irrigation. Water would be available only seasonally. (vi) Analysis of a series of aerial photographs, including color infrared imagery flown at a time of year to show any late summer and fall differences between upland and valley floor vegetative growth and of a scale adequate for reconnaissance identiflcation of areas that may be alluvial valley floors. Late-summer/early fall imagery acquisition has been contracted and should be completed by October 10, 2005. Major differences are not anticipated for areas other than wetlands and immediately adjacent transitional zones. During October 2005 Maxim will refine the map boundaries and make observations regarding slopes and apparent historic surface use. Based on our previous observations, Maxim anticipates that the following findings will be validated: 1) Alluvial materials are present in valley bottoms in the Jubb Creek, Collom Gulch, and Little Collom Gulch drainages; "Scientists and Engineers Commffted to Client Satisfaction"