5.1 Site "A" 



35. The sui-vey dive was conducted in an approximately 0.25 

 kt (east to west) current. Horizontal visibility was 

 approximately one meter. A high density of suspended material 

 over the bottom (nepheloid layer) was approximately 2 cm deep and 

 moving with the current. The substrate surface consisted of fine 

 silt material with 3 m wide patches of shell hash covering 

 approximately 10% of the surface in the dive area. The bottom 

 was flat with no deep vertical burrows. Crustacean activity was 

 the apparent major source of surface bioturbation. 



36. This site had a diverse megafaunal assemblage (Table 5- 

 1) dominated by crustaceans. Juvenile rock crabs, Cancer 

 irroratus , (2 to 3 cm, carapace width) were observed tracking 

 over the bottom and burrowing under shell debris or in open 

 sediments. Small hermit crabs, Paqurus longicarpus , were also 

 very abundant. Mobile crabs created tracks in the sediment 

 surface, and burrowed crabs sifted sediments through their 

 mandibles; both activities destabilized surface sediments. 

 Lobsters, Homarus americanus and cunner, Tautoqolabrus adspersus . 

 were attracted to debris on the site, because both species 

 require cover and exhibit thigmotactic response to small-scale 

 topographic features. 



5.2 Site "B" 



37. The survey dive was conducted in an approximately 0.1 

 kt (east to west) current. Horizontal visibility was 

 approximately 0.75 meter. The substrate consisted of a 1 cm deep 

 fine silt layer over gray-black clay material. The surface was 

 flat and featureless. Tree branch debris was present. Animal 

 tracks were ubiquitous over the surface. 



38. As at the "A" site, crustaceans were the dominant 

 megafaunal group (Table 5-1) and responsible for major surface 

 bioturbation of sediments. No deep vertical burrows were 

 observed at this site. 



6.0 CONCLUSIONS 



39. The August 1985 bathymetric survey revealed the 

 presence of three disposal mounds in the WLIS disposal site. The 

 newest mound ("C") is the result of disposal operations occurring 

 since the June 1984 survey. The post Hurricane Gloria survey did 

 not detect redistribution of the disposed dredged materials at 

 the 15-20 cm level of resolution obtained with the precision 

 bathymetric survey techniques used. 



40. The August REMOTS data indicate that dredged material 

 is concentrated across the central and southeastern portions of 

 the survey area. In general, western Long Island Sound is a 



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