342,900 cu yd. The total loss from the project during the second year was 

 539,700 cu yd, and the cumulative loss from the project during the first 

 2 years was 604,000 cu yd or about 302,000 cu yd/year. 



39. Even with the rather substantial sediment losses, as of May 1984 

 the project remained in excellent condition south of sta 100+00 where a 

 considerable portion of the construction berm was still intact. North of 

 sta 100+00 to 116+40 at the south end of rubble seawall, the berm and dune 

 section had experienced some damage as the erosion had progressed beyond the 

 construction berm into the storm berm portion of the authorized profile. In 

 front of the seawall, the sand level had essentially been reduced to approxi- 

 mately that of the 1981 prefill condition. The 4,000 ft of beach north of the 

 project continued to accrete during the second year, gaining 456,500 cu yd for 

 a total net gain of 673,600 cu yd between August 1982 and May 1984. 



Project Volume Changes 



40. Part of the erosion from Carolina Beach following the 1982 recon- 

 struction was probably the result of fill material being sorted by waves. 

 Sorting occurs as the waves redistribute the discrete particle sizes in the 

 fill material to their point of equilibrium on the profile. However, some of 

 the material, particularly the finer fraction, may not be stable at any loca- 

 tion on the profile and is either swept out of the project area by littoral 

 currents or carried to and distributed over the deeper portions of the beach 

 profile where it cannot be detected by existing survey techniques. 



41. In the case of the 1982 fill, a large amount of the finer material 

 appeared to be lost during the filling operation and not as a result of wave 

 sorting. For example, before and after dredging surveys made in the borrow 

 area indicated that 3,662,000 cu yd of fill was dredged, while beach profile 

 surveys taken before and after placement of the fill indicated that only 

 2,941,000 cu yd were placed on the beach. Excluding any inaccuracies in the 

 survey data, it appears that, for every cubic yard of material that remained 

 on the beach during construction, approximately 1.25 cu yd of material was re- 

 moved from the borrow area. 



42. Granulometric analysis of the borrow material made on samples ob- 

 tained from borings prior to dredging and auger samples of the in-place fill 

 material indicated that some fines were lost during placement. The analysis 



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