based on the geological, hydrographic, and biological data obtained in the 

 field, and the need for accurate monitoring before and after the disposal 

 of spoils. 



Another study by the Virginia Institute of Marine Sciences assessed 

 the effects of spoil disposal for two dredge operations in the lower 

 Chesapeake Bay area (Harrison, W. , 1967). In one operation 1.26 million 

 cubic yards of spoil were dumped in a rectangular area 0.5 by 1.0 

 nautical mi., in depths of 75 to 96 feet. 



Disposal of spoils in this area appeared to have only a transitory 

 effect on infauna and epifauna populations. Recolonization in areas of 

 dredging and disposal was rapid due to the active migration of the ani- 

 mals and to the hydrodynamic distribution of juvenile and larval stages. 



An extension of the same study monitored the possible spoil buildup 

 on an oyster ground in the York River estuary, in response to anticipated 

 spoil deposition from an outfall located 0.8 to 2.0 miles in a down- 

 estuary direction. It was concluded that the general trend in sedimen- 

 tation along the perimeter of the oyster grounds before, during, and 

 after the dredging, was one of slight erosion. Dredging and spoil dis- 

 posal had no observable effect on the character of the river bottom or 

 the natural animal population within the study area. Mortality of the 

 oysters was not above normal. 



A study of the Rappahannock Shoal and spoil disposal area (Brehraer, 

 et al, 1967) indicated a greater species diversity and number of organ- 

 isms in the spoil areas than in the ooze-covered natural substrate in the 

 deeper parts of Chesapeake Bay. Infaunal organisms with the exception 

 of certain worms, did not recolonize the dredged channel, and it was con- 

 cluded that faunal groups comparable to those of adjacent shoals would 

 not be supported. However, it was speculated that in time spoil areas 

 would eventually reestablish their population densities. 



4. Southeast Florida 



Untreated sewage along the coast of southeast Florida is disposed of 

 by ocean outfalls. The discharge points of these outfalls vary from a 

 depth of 16 feet, 6,400 feet offshore, to a depth of 90 feet, 10,000 

 feet offshore. Riviera Beach, Palm Beach, Lake Worth, Delray Beach, 

 Boca Raton, Pompano Beach, Hollywood, North Miami, Miami Beach, and 

 Miami are the coastal communities using ocean outfalls. 



The biological, chemical and physical properties of the coastal 

 waters off Pompano, Boca Raton, and Delray, were investigated over a 

 3-year period by a study funded by the Environmental Protection Agency 

 (Florida Ocean Sciences Institute, 1971). The biological investigation 

 included surveys of the microscopic benthic communities and microbiotic 

 organisms of the sediment-water interface and of the free drifting 

 plankton. This investigation concluded that the number of planktonic 



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