I . Rhepoxynius hudsoni - A free-burrowing amphipod related to a 

 species used in sediment toxicity testing, was found in 

 moderate numbers on sandy dredged material in 1974 and 1987. 



A group of species found on natural silty bottom (the 

 bivalve Nucula spp. and the anemones Ceriantheopsis americana and 

 Edwardsia elegans) had increased in density southwest of the site 

 in sediments which may be the result of dredged material disposal 

 operations. 



The general pattern of faunal distribution presently 

 found in the Brenton Reef disposal area was established within four 

 years after large-scale disposal ended. Between 1974 and 1987, 

 population numbers increased on dredged material, but the general 

 pattern of species number and community types has remained the 

 same. Throughout the area, sediment grain size and organic matter 

 content are probably the most important determinants of faunal 

 makeup; the impact of sediment contaminants in the dredged material 

 on the recovery process is harder to assess. 



The process of recovery of continental shelf benthos from 

 disturbance and pollution is still largely unknown. Previous 

 studies of benthos from offshore disposal areas in the New York 

 Bight and Massachusetts Bay have not filled this data gap because 

 of continuous releases of a great variety of materials, the spatial 

 complexity of the sites, and, in the case of New York, the 

 additional confounding variable of poor water quality. Such 

 variables do not exist at the Brenton Reef Site, as virtually all 

 the introduced material came from a single dredging operation, 

 there has been a long period of recovery, and water quality remains 

 very high. This consistency at the Brenton Reef Site provides an 

 environment where the processes of long-term recovery of 

 continental shelf benthos can be assessed and analyzed. 



5 . SUMMARY 



The physical boundaries of the historic disposal mound at 

 the Brenton Reef disposal site had not changed since the last 

 survey of the area; the mound was a well-defined feature centered 

 just inside the western boundary of the disposal site with a 

 diameter of roughly 1600 meters and a minimum depth at the apex of 

 25.5 meters. 



The areas of Brenton-A and Brenton-B were characterized 

 by extensive glacial drift deposits. A relict channel system that 

 drained the landward side of the recessional moraine was observed 

 in sub-bottom profiles trending northeast-southwest through these 

 two areas. 



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