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SUMMARY suitable for trout and which will enhance downstream water quality. 3. Deferring construction of a powerplant at Jordanelle Dam. Present policy provides for increasing non-Federal par- ticipation in powerplants developed in conjunction with Federal projects. In addition, projected demands for power have decreased significantly. Consequently, con- struction of a powerplant at Jordanelle will be deferred awaiting non-Federal participation. The outlet works will be designed to accommodate the convenient addition of a powerplant at some future date. The potential to produce about 10.4 megawatts (MW) will remain, ss stated in the FES. The table on the following page shows a comparison of design infor- mation presented in the FES and information applicable to the current plan. Dam safety and alternative damsites Because of complex geologic conditions, the concerns of the mining industry, and expressions of concern for dam safety by the public, Recla- mation has undertaken a more extensive geologic investigation of the site than is normally conducted. The investigation included core sam- pling from over 170 drill holes ranging to a depth of 1,805 feet at the damsite, excavating trenches to define geologic structures, detailed mapping, conducting petrographic and geophysical surveys, and others. In 1982, Reclamation assembled an impartial panel of professional geologists with international reputations to evaluate the data obtained, the dam's safety, and proposed designs. The panel found a safe dam could be built at the site, barring any unfavorable new findings. Reclamation recalled the panel in the fall of 1986 to review additional data ob- tained since 1983. The 1986 panel concurred that a safe dam could be built and that the proposed embankment dam or a composite embankment dam would be suitable for the site. The panel further concluded that the foundation and abutments could be considered free of faults or shears that would pose a potential for surface faulting. The State of Utah also reaffirmed the Jordanelle site after conducting a separate investi- gation of alternative damsites in 1983. Finally, Jordanelle Dam is being designed to withstand the maximum credible earthquake and to pro- vide flood control. Based on studies and analyses of the reservoir basin by the Bureau of Reclamation, the Bureau of Mines, and independent contractors, it was concluded that no significant effects would occur to commercial mine workings or to mineral resources. S-3