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whatever profit they have built into this project. Is the project really needed by the water users; the livelihood of farmers will be compromised as well as that of the Gunnison River. RESPONSE: The Gunnison River is one of the few major fisheries in the State that is considered a wild trout fishery; it is not maintained by stocking. The CDOW has done an extensive study of trout reproduction in the river and has concluded that project flow changes would not adversely affect this situation. Habitat conditions with the development alternatives would not be optimum, nor are they optimum under the no-action alternative. Temperatures would increase during the summer, especially in the North Fork to Austin reach of the river. However, closely examining the flow tables in the EIS shows that flow changes, and therefore temperature changes, are the least during the summer because the Tunnel is at or near capacity for irrigation, particularly during dry years. Please see the index of comments and responses for additional information on fisheries. Flows under the no-action alternative differ from actual gauge data on the Gunnison River; this phenomenon occurs for several reasons. The no-action flows are simulated flows that consider the operation of the Aspinall Unit. Simulated flows were used for the hydrologic analysis on this project because not a long enough post-Aspinall record period exists for meaningful comparison. Simulated flows are necessary to determine both post-project flows and water availability for hydropower and to present an accurate prediction of impacts. Errors in actual flow tables (see attachment B) were also found in the DEIS and have been corrected. The no-action flows sometimes differ from actual flows even when the Aspinall Unit was operating. This phenomena occurs for several reasons. Filling Blue Mesa Reservoir accounts for major differences for several years beginning in October 1965, as do the construction and filling of Morrow Point and Crystal reservoirs (which ended in the mid-1970's). It is not possible to make a valid short-term comparison between the simulated operation and the actual or historical operation of the Aspinall Unit. Many factors that affect the actual operation of the unit, such as power system emergencies, downstream water demands that vary from month to month and year to year, errors in forecasting inflows, and operator judgment cannot be simulated by the computer operation model to match identical flow conditions for a given year. However, the model is extremely useful in showing longer term trends and is considered accurate in predicting the frequency of low flows. Studies of the Uncompahgre River, including historical accounts, indicate that the potential for erosion is high under existing P-15