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(CERC) long-term field investigation relating longshore transport volumes to 

 wave energy thrust measurements. The data collected for this study consist of 

 28 vibratory cores of sediments, 8 cores from sites along a native beach 

 profile, and 20 cores from sites within the trap. The long-term sediment trans- 

 port study provided the remaining data used in this report. 



In general, the trap functioned as designed, trapping the bulk of longshore 

 transport which entered the trap mouth in a series of pulses or surges of sand. 

 From an analysis of the textural data it is concluded that sediment distribu- 

 tion within the trap area is similar to that of the updrift coastline although 

 the trapped sand is slightly finer and better sorted than the native beach 

 sand. Also from the textural distributions within the trap, it is concluded 

 that the "trapping" process slightly reduces the overall predicted performance 

 of the sediment as beach fill but that bypassing could be planned to utilize 

 the textural patterns in the construction of a beach fill downcoast. Finally, 

 grab sampling rather than core sampling is the appropriate method for sampling 

 native beach sediments, whereas either coring or grab sampling appears 

 adequate for characterizing trap-fill sands. 



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