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. proposed dam monitoring program are provided in the geotechnical report, Appendix D. Outlet works repairs would also be Included under Alternate A. . Alternate B Under Alternate B, the dam would be heightened so that the one- half probable maximum flood could be safely routed through the reser- voir and spillway. Assuming the outlet works Is operating, the flood could be passed if the dam crest is raised six feet to elevation 9469. About 1.9 feet of freeboard would be available above the maximum water surface. If the outlet works was not operating, the freeboard would be about 0.3 foot. As discussed in the geotechnical report, Appendix D,. the down- stream slope of the dam embankment would be stabilized if the dam Is enlarged at a two horizontal to one vertical slope. The proposed dam enlargement using this slope is shown as Figure 11. Approximately 26,000 cubic yards of rock (in place) would be required to raise the dam crest to elevation 9469. Abundant supplies of suitable rock are available near the dam. As shown on Figure 11, the new dam toe would extend very near the outlet works portal. It is estimated that 100 cubic yards of concrete would be required to protect the dam toe from erosion during outlet works discharge. A construction access road to the dam toe would be required, The road would be cut into the north abutment by dozers at a maximum grade of about ten percent. The road length from the dam crest to the dam toe would be about 900 feet. Also included under Alternate B would be the outlet works repair, north abutment monitoring program, and flood warning program. Alternate C Under Alternate C, the dam would be heightened and the spillway enlarged so that the probable maximum flood could be safely routed through the reservoir and spillway. Figure 12 shows the proposed . -45-