m 



- 6 - 



the spores of C. perf ringens , a bacterium consistently found 

 in the feces of man anu some other warm-blooded animals, were 

 used to trace the movement of sewage in the Apex. Highest 

 spore densities were found in sediments in the Christiaensen 

 Basin to the immediate west of the sewace sludae dumositft. 

 Spore densities in sediments extending from the Basin toward 

 the Long Island coast decreased exponentially with shoaling 

 water depth to the 18-meter isobath. Sewage solids appear to 

 be translocated to the southeast from the Christiaensen Basin 

 along the course of the Hudson Shelf Valley. Eleve'.ed spore 

 densities were detected at least 105 kilometers down t'.e Hudson 

 Shelf Valley. Similar distributions of the protozoan, Acantha - 

 moeba , have also been observed. 



Areas receiving settled sewage sludge and other fine- 

 grained material are characterized by benthic populations dis- 

 similar from those of the less contaminated continental shelf. 

 Populations of contaminant-tolerant species are high and more 

 sensitive species are nearly absent. The most heavily affected 

 areas are those adjacent to the dredged material and sewage 

 sludge (12-mile) dumpsites, the Christiaensen Basin and the 

 Hudson Shelf Valley. These areas are characterized by finer, 

 muddier sediments (Figure 3), however, which normally support 

 very different bottom communities than more coarsv. , sandy or 

 rocky bottoms. These same areas would be expected to accumu- 

 late contaminants of coastal or estuarine origin even if dumping 



