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"I I I I I I I I I I I I I I I I I I I Measurements were made along the crest of the dam and the downstream face. Test locations were limited by ladder height and the presence of a large snowbank against the downstream face. Locations and results of the pulse velocity test are shown on Figure 5. The values shown were corrected for the presence of steel rebar in the upstream face. Velocities averged 11,740 feet per second (fps) in the horizontal direc- tion with a range of 5,630 fps to 19,920 fps for 28 tests. Velocities in the vertical direction averaged 9,620 fps for seven tests with a range of 4,960 fps to 18,400 fps. Lower velocities in the vertical direction can be attributed to deteriorated construction lift joints. A correlation between general concrete condition and pulse velocity given by Whitehurst (1966) is shown on Table II. General concrete condition based on pulse velocity was well distributed from "very poor" to "excellent". This information is in agreement with the drilling data. There are rough correla- tions between the static Modulus of Elasticity (Es) of concrete and pulse velo- cities. Given an overall average pulse velocity of 11,300 fps then Es is approximately 2 million psi, based on a correlation between pulse velocity and static Young's Modulus of Elasticity (Malhotra, 1973). Concrete Permeability The dam in its existing condition is quite permeable. Water was observed flowing at greater than 50 gpm through a deteriorated section 35 feet below the crest with one-foot reservoir head. During drilling operations no water returned up the holes and was observed flowing out of various horizontal construction joints. Packer tests were attempted in all the holes; however, caving conditions prevented insertion of the packer equipment in some cases. Falling-head tests were attempted where packer testing was not performed. -13-