218 



the eO-Mile Sits is less turbid, more saline, has lower primary produc- 

 tivity, and lower concentrations of metals and organic pollutants. These 

 onshore-offshore differences are normal characteristics of the coastal 

 and shelf waters of similar areas with shallow continental shelves and 

 substantial river discharges (Section 7.5). 



The initiation of sewage sludge disposal operations at the 60-Mile Site 

 would significantly increase the inputs of a variety of contaminants 

 to the area, but there are insufficient data to determine whether such 

 dumping would increase background concentrations of any contaminant 

 following initial mixing. However, reasonable estimates indicate that 

 any such increase would be small and should be transient due to the 

 available dilution water and the consistent current flow at the site. 

 The 1978 FEIS concluded that: 



"Degradation of coastal water quality is not expected, even if 

 greatly increased volumes of sludge are dumped at a new site in 

 the Northern [60-Mile Site] or Southern Area. 



The quality of Bight Apex waters will not be significantly 

 improved by using a new sits in the Northern [60-Mile Site] or 

 Southern Area because most pollutants entering the Apex come from 

 sources other than sludge dumping (primarily dredged material 

 dumping, inland runoff, and wastewater discharges)" (EPA 1978, 

 p. 205). 



Any increase in the size of the 60-Mile Site compared to its present 

 size would be beneficial in enabling minimization of any transient water 

 quality effects resulting from ocean dumping operations. 



Sediment and Benthos 



Since waste disposal has not occurred at the 50-Mile Site, the primarily 

 sandy sediments within and near the Site reflect natural geological and 

 chemical conditions (Section 9.2). Although several baseline studies 

 of sediment chemistry have been conducted at the northern and southern 

 areas, data have not been collected within the specific 31 km'^ that was 

 designated as the interim alternate dumpsite (Section 8.0). The avail- 

 able data for the northern study area do indicate that metal and organic 

 sediment concentrations are lower than those reported for the New York 

 Bight apex. 



Because ocean dumping has never occurred at the 60-Mile Site, the data 

 available to assess the potential for sewage sludge accretion in sedi- 

 ments at the site is minimal. However, based on a simplistic theoretical 

 diffusion and dispersion model, only a small fraction of the heavier 

 particulates is expected to reach the sea floor, although the majority of 

 dumped particulates will remain within the water column. Any settled 

 particulates would be subject to the combined actions of biological 

 sediment reworking, and resuspension and redistribution by hydrologic 

 currents. Since little or no accretion occurs at the 12-Mile Site, it is 

 expected that no substantial accretion would occur at the deeper and more 



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