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5.0 CONCLUSIONS 



The REMOTS® sediment-profile photographs at CSDS in August 1992 strongly 

 suggest that sand at the disposal site is continuing to be transported over, and accumulating 

 on, the fine-grained dredged material mound that was created at CSDS from sediments from 

 North Cove. Although there is no net accumulation between bathymetric surveys in May 

 1992 and August 1992, the resolution of that acoustic system (>20 cm) may be too large to 

 measure the combined sand accumulation and mud compaction. The surface sediment 

 density study at CSDS did not reveal well-defined areas of fine-grained sediment. Instead it 

 showed variability in the data with density values ranging from 1.3 up to 2.0 gcc" 1 over 

 50 m. The denser sediments were concentrated north of 41° 12.75' N, which generally 

 corresponds to the location of sandy sediments with shell lag and pebbles. The subsurface 

 density data did not prove to be a reliable means of locating changes in sediment density. 

 Different sediment types observed in the REMOTS® sediment-profile photographs were, in 

 many cases, less than 15 cm thick, the resolution of the acoustic profiling system. 



Monitoring Cruise at the Cornfield Shoals Disposal Site, August 1992 



