that have been conducted on the BRH composite sample at ERL-D 

 have shown that the concentration of 2 , 3 , 7 , 8-tetra-CDD is much 

 lower than the preliminary results indicated. However, this 

 material does contain numerous PCDD and PCDF compounds (ERL-D, 

 unpublished data) . 



The purpose of the present study was to measure the 

 levels of PCDDs and PCDFs in five archived sediment samples from 

 Black Rock Harbor in Bridgeport, CT and Central Long Island 

 Sound in order to confirm the results from ERL-D. The five 

 samples analyzed included a sample of the original BRH composite 

 sediment, dredged material collected from the wetland and upland 

 disposal sites, and two sediment core samples from the CLIS 

 disposal area. The samples chosen from CLIS included one from 

 the 4-6 cm section of a sediment core taken from 200 meters east 

 of the FVP disposal mound center on BRH dredged material. This 

 sample was chosen because it contained the highest PCB 

 concentration (Munns et al.. In preparation) on the last sampling 

 date (10/22/85) of the FVP study. It was selected to represent 

 potentially a worst case condition now existing at the CLIS 

 disposal site. In addition, a sample of the 4-6 cm section of a 

 sediment core from the Reference station was also chosen for 

 comparison. This sample should represent background levels in 

 Central Long Island Sound. 



Analysis of all five samples was performed by Battelle 

 Columbus Laboratories (Columbus, Ohio); the concentrations of 

 PCDDs and PCDFs measured in these samples are reported. The 

 analytical procedures used to obtain the results are described, 

 and a discussion of the results in comparison with those reported 

 by other studies is included. 



ANALYTICAL METHODOLOGY 



Sample Extraction and Analyte Enrichment 



Eleven gram aliquots of dried sediment samples were 

 weighed by difference into Soxhlet extraction thimbles and 

 spiked with the stable carbon isotopes of PCDDs and PCDFs listed 

 in Table 1. The Soxhlet extractors were assembled and the 

 samples extracted for 18 hours with 250 ml of benzene. After 

 extraction, the benzene extracts were concentrated to 

 approximately 5 ml with 3 -stage Snyder columns. Laboratory 

 method blank and native spike samples were prepared with the 

 samples. 



The sample extracts were diluted to 10 ml with hexane 

 and washed with three 10 ml aliquots of concentrated sulfuric 

 acid. The combined acid washes were extracted with hexane and 



