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(Section 13.2). This dilution is the result of a two phase process: a 

 very rapid initial wake dispersion, followed by slower oceanic dispersion 

 processes (Section 18.2). Oceanic dispersion processes are particularly 

 influential at the 106-Mile Site, which is characterized as one of the 

 most highly dispersive ocean dumpsites in the world (Section 9.7). 



2.4 OTHER USES OF THE SITE 



Few activities other than waste disposal occur in or near the 106-Mile 

 Site: vessel traffic is light, fisheries resources are sparse, and 

 commercial fishing in the area is limited. Further, the 106-Mile Site 

 is not identified as an area with significant potential for minerals 

 development although proposed oil and gas lease tracts have been 

 identified nearby on the continental shelf (Section 4.5). 



2.5 TYPES AMD QUANTITIES OF WASTES 



More than 100 different dumpers have used the 106-Mile Site for waste 

 disposal since 1961, but the Site is currently used only for the ocean 

 disposal of industrial wastes and sewage treatment plant digester clean- 

 out. From 1961 to 1978, approximately 5.1 million metric wet tons of 

 chemical wastes, 102 thousand metric wet tons of sewage sludge, and 237 

 thousand metric wet tons of digester residue were dumped at the site 

 (Chapter 5). Since 1978 when a high of 876 thousand wet tons of waste 

 were dumped at the site, annual quantities dumped have decreased to a 

 1981 level of 267 thousand wet tons. DuPont Grasselli is currently the 

 only active industrial dumper at the 106-Mile Site, although OuPcnt-Edge 

 Moor still holds a permit. Based on the volume of waste dumped during 

 1981, the transfer of all sewage sludge disposal operations from the 

 12-Mile Site to the 106-Mile Site would increase the total volume of 

 waste dumped at the 106-Mile Site 25 times (Chapter 5). 



If all current sewage sludge operations were transferred to the 106-Mile 

 Site and other inputs remain the same, sewage sludge would become the 

 major contributor of most contaminants dumped' at the Site, with an addi- 

 tional average input of about 550 tons of solids per day (Section 6.4). 

 However, since normal background suspended solids within the upper 100 

 meters of the water column at the 106-Mile Site probably total more than 

 10,000 metric tons, these additional 550 tons of suspended solids would 

 probably have little or no effect on water quality or the environment if 

 adequately dispersed, as expected (Chapter 7). 



2.6 EFFECTS OF SEWAGE SLUDGE DUMPING 



The possibility of environmental and human health effects of sewage 

 sludge dumping at the 106-Mile Site must be assessed in order to desig- 

 nate the site. In addition, the economic effects are a reality and 

 should be examined. The primary adverse effect of moving sewage sludge 

 dumping to the 106-Mile Site would be an increased financial burden upon 

 all municipalities and regulatory agencies involved in the dumping pro- 

 cess. As noted in the 1980 FEIS, "Use of the 106-Mile Site for sewage 

 sludge disposal would be environmentally acceptable under carefully 

 controlled conditions. . .however, substitution of the 106-Mile Site for 



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