Five seismic traverses were run at site 917-1; the approximate locations are shown 

 in figure 15. The small circles on the double lines represent the approximate loca- 

 tions at which the seismic interpretations are valid. Following are the interpreta- 

 tions, with the accompanying seismic velocities included: 



Traverse 1: 5.5 feet of loose material, velocity = 1,050 feet per second 



(f.p.s.) overlying fractured rock (3,125 f.p.s.) which extends 

 at least to an additional 30-foot depth. 



Traverse 2: 6.2 feet of loose material (850 f.p.s.) overlying fractured 

 rock (2,350 f.p.s.) which extends at least to an additional 

 20-foot depth. 



Traverse 3: 5 feet of fill material (900 f.p.s.) overlying 13.2 feet of 

 loose material (900 f.p.s.), beneath which is fractured rock 

 (4,500 f.p.s.). 



Traverse 4: 5.15 feet of loose material (540 f.p.s.) overlying a 

 20-foot thick layer of fractured rock (2,330 f.p.s.), 

 beneath which is sound rock (20,000 f.p.s.). 



Traverse 5: 3.5 feet of very loose material (540 f.p.s.) overlying at least 

 20 feet of denser material (1,100 f.p.s.). 



Also shown in figure 15 are the approximate test pit locations. 



Lines A-A, B-B, and C-C in the figure are the locations of the profiles sketched 

 adjacent to the plan view in figure 15. 



Figure 16. — Representative profile 3 site 917-1. 



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