SECTION V. SUMMARY AND CONCLUSIONS 



Much data have been gathered primarily on the physical, chemical, and 

 biological characteristics of the waters and sediments of the New York 

 Bight, as related to disposal of waste materials such as sewage sludge, 

 dredge spoils and acid-iron wastes. The studies summarized in this re- 

 port were supported by the Corps of Engineers under contracts with the 

 Smithsonian Institution, the Sandy Hook Marine Laboratory of the National 

 Marine Fisheries Service, the State University of New York at Stony Brook, 

 the Woods Hole Oceanographic Institution, and the Sperry Rand Corporation. 



The studies completed to date, include hydrographic, geological, 

 chemical, biological investigations, and a feasibility study for a re- 

 motely controlled sensing system that could assist regulating agencies 

 in detecting the location and dump status of waste disposal vessels 

 operating in the New York Bight. Because of the specialized technical 

 nature of this latter study, only the major findings and conclusions of 

 the environmental studies on the effects of waste disposal are summarized 

 below: 



Dispersion and Movement of Waste - The dispersion and movement of 

 waste materials after dumping were correlated with general circulation 

 patterns of the Bight deduced from surface and bottom drifter studies. 

 These circulation data indicate a strong flow at the bottom along the 

 axis of the Hudson - Ambrose Channel into the mouth of the Hudson 

 Estuary. Under tidal circulation the ebb in the Lower New York Bay is 

 generally stronger than the flood and there is a net transport of water 

 outward from the Hudson Estuary. The data also indicates that there is 

 a general clockwise circulation in the Bight. Surface flow shows a strong 

 seasonality, while mild seasonal variation is indicated for bottom flow. 

 During winter, surface flow in the Bight appears to be predominantly to 

 the southwest, away from the coast. At other times flow tended northward. 

 The preliminary studies did not incorporate the findings of water 

 circulation patterns, in detailed analysis of the distribution of 

 important constituents of the discharged waste in either the water 

 column or the benthos. 



Evident, however, is that the extent of dispersion and movement of 

 waste materials in the Bight relates to water circulation. The studies 

 have shown the presence of high concentrations of organic materials in 

 the sediments of the dumping grounds and surrounding areas which 

 correlates well with the distribution pattern of coliform bacteria and 

 heavy metals. The slowly settling sewer sludge generally moves northward, 

 resulting in the deposition of organic material for some distance to the 

 north and northeast of the dumping grounds. 



Circulation patterns in the Bight which were obtained by the use of 

 drifters, although useful for indicating the onshore component of net 

 water transport, cannot be correlated effectively to an isotropic dis- 

 persion, seasonal variances, or transport mechanisms of waste materials 

 of diverse physical properties. Similarly, such drifter studies cannot 



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