Samples from MQR Center contained the fewest species and 

 individuals of any station. The dominant species, M^. ambiseta , N. 

 incisa, and M;. cristata , are members of the normal CLIS silt/clay 

 assemblage. The large numbers of the bivalves Mulinia and Nucula 

 found at the CLIS reference station were conspicuously absent. In 

 the absence of pollution-indicating species, some physical cause 

 of low abundance must be hypothesized. 



3.7 Body Burden Analysis 



Triplicate analyses were conducted on Nephtys incisa 

 collected from the reference, STNH-N, FVP, and MQR stations. Only 

 a single sample was available from the CLIS-86 mound. These 

 samples were analyzed for eight inorganic elements and reported on 

 a dry weight basis (Table 3-29) , as well as on a wet weight basis 

 (Table 3-30) . Samples were also analyzed for several PCB 

 formulations (Table 3-31) . 



Statistical analyses (Kruskal-Wallis) were conducted on 

 the results to test for concentration differences between organisms 

 collected from the disposal mounds and those collected from the 

 reference station (Table 3-32) . PCB concentrations could not be 

 tested statistically because all of the samples showed 

 concentrations below the analytical detection limits. Also, the 

 CLIS-86 data could not be tested because only a single sample was 

 available from that location. 



The results from statistical analyses of the inorganic 

 data showed that the concentrations of Cr, Cu, and Zn were 

 significantly elevated (p<0.05) in Nephtys collected from the 

 STNH-N station compared to levels in organisms collected from the 

 reference station. The concentrations of As and Pb were 

 significantly lower in the STNH-N polychaetes compared to those 

 from the reference station. 



The concentrations of Cr, Cu, and Pb were significantly 

 higher in the Nephtys from FVP compared to levels in organisms 

 collected from the reference station. The same three elements also 

 showed significantly higher concentrations in Nephtys collected 

 from MQR. 



4 . DISCUSSION 



4.1 Topographic Changes and Disposal Mound Stability at CLIS 



One objective of the 1986 field operations was to 

 delineate the extent and topography of the dredged material deposit 

 resulting from disposal during the 1985-86 season. The bathymetric 

 survey showed a significant accumulation of dredged material at the 

 buoy in the northwest corner of the site. The new CLIS-86 mound, 



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