(0-2cm) contained lower concentrations for roost contaminants; these 

 concentrations also were significantly lower than those in core 

 sections (0-10cm) collected at FVP in 1983. This might reflect 

 increased dilution or oxidation of the disposed material as a 

 result of bioturbation. As indicated, the MQR mound contained 

 significantly elevated concentrations in both the Top and Bottom 

 core sections for all of the parameters measured. 



Several other investigators have reported the 

 concentrations of relevant elements or compounds in Central Long 

 Island Sound sediment samples from areas away from dredged 

 material. In general, the concentrations that have been reported 

 are very similar to those measured at the reference station in the 

 present study. Also, Munns et al. (in press) sampled sediment on 

 the FVP disposal mound over a period of several years. The 

 contaminant concentrations they reported were generally higher than 

 the levels detected in the present study. 



The faunal assemblage at the CLIS reference station was 

 similar to that found at the same location in the EPA/COE Field 

 Verification Program. Most of the species recovered at the FVP 

 Center station were ones adapted for soft bottoms. The STNH-N 

 Center fauna was dominated by tube-dwelling polychaetes, and 

 several species which have a strong association with sandy bottoms 

 were also present at this mound. The results of the benthic 

 community analysis generally confirmed the REMOTS® infaunal 

 successional designations and OSI rankings of the various mounds. 

 The new CLIS reference station, STNH-N mound, and FVP mound were 

 essentially similar in terms of mean OSI rank and species richness, 

 while the MQR mound had a significantly lower mean OSI and species 

 richness. 



At the MQR and FVP mounds, Cr and Cu levels were elevated 

 above reference both in surface sediments and in the tissue of the 

 polychaete, Nephtys incisa. These results suggest some correlation 

 between sediment contaminant levels and bioaccumulation. In 

 contrast, elevated concentrations of Cr, Cu, and Zn in Nephtys at 

 the STNH-N mound did not correspond with elevated sediment levels 

 of these three metals. The sand cap at this mound might have been 

 effective in isolating or diluting the metal concentrations in the 

 surface sediments, but the polychaetes could have been exposed to 

 the metals in the underlying capped material as a result of 

 vertical migration or head-down feeding. Bioaccumulation of 

 inorganic contaminants is a possible explanation for the anomalous 

 recolonization rates at the MQR mound. The fact that several 

 metals were also elevated in Ne phtys at FVP, a mound with 

 relatively high rates of colonization, suggests that other factors 

 might have influenced recolonization at MQR. 



The concentrations of several elements in Nephtys at the 

 various disposal mounds sampled in July 1986 were generally similar 

 to or lower than those reported by Munns et al. (in press) for 



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