of the in situ or boring samples resulted in a composite mean particle size of 

 1.72 phi* and a standard deviation of 1.01 phi, whereas the auger samples of 

 the in-place material had a slightly coarser and less well-distributed range 

 of particle sizes with a composite mean of 1.49 phi and a standard deviation 

 of 0.90 phi. The critical ratio (as defined in the Shore Protection Manual ** 

 (1984)) between these two composite distributions is 1.27, implying that for 

 every cubic yard of material that remained on the beach during construction, 

 1.27 cu yd of material was removed from the borrow area. The agreement 

 between the critical ratio and the actual amount of overdredging from the 

 borrow area indicates a loss of a considerable portion of the finer borrow 

 material during placement, as was anticipated. 



43. Volume losses from the fill during the first 2 years of project 

 operation, discussed above and shown in Table 4, were determined from surveys 

 of the fill following construction and, therefore, do not include the losses 

 that occurred during placement. Some additional sorting losses may have taken 

 place during the first 2 years of operation; however, these losses could not 

 be determined. 



44. The overall performance of the fill during the first year was ex- 

 cellent and appeared to be responding as expected with large quantities of 

 material being displaced seaward from the construction berm. During the 

 second year, much of the material that had moved offshore to between -4 and 

 -25 ft disappeared. Some of this material probably continued to move seaward 

 and was dispersed over the relatively flat bottom seaward of the 25-ft depth. 

 In addition to the losses downslope, large quantities of the fill material 

 were moved to the north and south beyond the project limits by wave-generated 

 longshore currents. 



45. The ocean bar channel at Carolina Beach Inlet has, for the past 

 several years, been oriented parallel to the downdrift or south side shoreline 

 as shown in Figure 4. With this bar channel configuration, the rate of sand 

 movement from north to south past the inlet has been greatly enhanced. For 

 example, between 1967 and 1973 during which time the bar channel was oriented 

 primarily perpendicular to the adjacent beaches, the rate of accretion within 



* d(mm) = 2. 

 ** Shore Protection Manual . 1984. 4th ed., 2 vols, US Army Engineer 

 Waterways Experiment Station, Coastal Engineering Research Center, US 

 Government Printing Office, Washington, DC. 



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