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SUMMARY (Continued) The existing interconnected transmission system is not adequate to accommodate the power which would be generated by the recommended plan. As a result, the Western Area Power Administration (Western) of the U.S. Department of Energy is investigating modifications to the Colorado River Storage Project system which would be required to provide the necessary transmission service. Additionally, Western is investi- gat ing the poss ibil i ty of wheeling thi s power over other ut il ities I existing transmission lines and the construction of new lines. Summary of Environmental Impacts Summary Table 2 is a comparison of net environmental impacts which would result from implementation of the five alternatives, including mitigation measures. The impacts are compared to future conditions expected without additional Federal development of the Bonneville Unit, although facilities to deliver the 197,600 acre-feet of water from the Uinta Basin to the Bonneville Basin without power generation would be the minimum required to maintain the basic integrity of the Bonneville Unit. The future without condition is used as a basis for comparison because impacts resulting from the delivery system without power genera- tion were not previously evaluated. Temporary and permanent impacts on topography and scenery would result from the construction of reservoirs, powerplants, transmission lines, and roads, and the upgrading of existing roads. Construction- related mitigation measures would include the contouring, topsoiling, and revegetation of these areas. Revegetation of native grasses, shrubs, and forbs would probably take about 5 to 10 years, whereas pinyon-juniper, mountain brush, and riparian communities would require about 25 years to return to conditions visually comparable to those existing. The scenic quality of the reservoirs would vary depending on water level fluctua- tions. During periods of low water, mudflats around the shoreline would detract from the esthetic appeal and recreational use. Powerline corri- dors have been alined to limit adverse visual impacts on scenery. Both permanent and temporary losses of vegetation would occur primarily to reseeded grass, mountain brush, and pinyon-juniper commun- ities. Permanent losses of vegetation, mostly from reservoir inun- dation, would total about 1,000 acres for the recommended plan, including about 45 acres of scarce riparian habitat. Temporary losses of vegeta- tion, mostly from construction of the Diamond Fork Pipeline and develop- ment of borrow areas, would total about 400 acres, most of which is reseeded and mountain brush communities. The construction of two large reservoirs on Diamond Fork and Fifth Water Creek would inundate floodplains and cause the loss of 47 acres of existing stream and associated riparian vegetation. In exchange, these reservoirs would provide 920 acres of wetland habitat but, because of fluctuating water levels associated with the peaking power operation, the exchange habitat would not be considered high quality. Additionally, 28 S-s