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co ~ (~ AVERY DAM PROGRAM i.\! It was originally planned to run a series of lines end to end in an north east direction along the left abutment parallel to the proposed dam axis. Another set of lines perpendicular to the first trending north-west were to be run at intervals as time permitted. The program actually executed is shown on the enclosed drawing. The north-east lines were not developed as extensively as planned, partly due to severe weather conditions on the first day of the survey and because lines 1 and 2 did not show the expected rise in top of bedrock at the south end of the lines. Therefore, lines 3 and 4 were random attempts to locate bedrock at a shallow depth. Line 4 was in- corporated into the longitudinal traverse parallel to the centerline. Shot point offset distances were chosen to best define the layers of interest. Three shot points of 25 ft were done to define the velocity of the surface layers. The remainder of the shot points were generally offset from 100 to 200 ft. to define the expected bedrock contact down to 100 ft. RESULTS Results for each individual line are attached and are shown as a plot of time versus geophone and shot point spacing. These data are also presented in the right hand margin in table form. Each line on the graph represents a constant velocity for the media penetrated. This velocity is written on the line. The breaks below the shot points are circled and can be calculated from the formula at the right. At the top of the page, the results of the line are shown in profile including the ground surface. The north end of line No.1 corresponds to drill hole DH-2 from the Bureau's investigation and the correlation is good. The boring showed ~ 5 ft of sandy silt versus 10 ft in the seismic. The drill hole showed + 100ft of coarse gravel overlying sandstone bedrock at about 106 ft; seismic showed 85 ft.