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1 - 15 - 1 1 1 1 1 1 1 Slope Protection: The on-site clays and fine sands and silts are susceptible to water erosion. Therefore, slopes and channels subjected to beach or stream type action will require protection. Several types of protection are possible. Riprapping can be used but due to the large difference between gradation of the fine rained c~nbanlarent materials and riprap, use of a filter ted or fabric below the riprap will be required as a transition. Well cemented sandstone excavated from the steep slope along the haul road would be a poten- tial source of riprap. A suitable riprap bedding material may be obtainable from granular borrow along the river; however, processing the material to proper gradation will be required. If water level fluctuation is confined to a relatively narrow range, partial pcotec- tion of the slope can be provided. For this case, a minimum 10 foot wide bench should be provided at the toe of the riprap. We understand that spillways through the embanlonent will also be provided. Due to the erodibility of the on-site fine rained soils in their natural as well as co;~acted condition, the spillway should be protected by use of riprap, slope mattress, grasses, etc. Protection should be adequate to prevent head cutting of the channel into the reservoir. Well Demented sandstone material could also be used for energy dissipaters. If water velocities are below erosion levels or periodic repair of spillways is conducted after periods of flow, the riprap can be eliminated. Instrumentation: Instrumentation in the form of settlement ~ronuments and open end observati~ wells should be provided to evaluate the performance of the structures during operation. We recommend a reference point monument be provided near maximum section on the crest