50 



aluminum and iron reduced the variability between replicates, further supporting a relatively 

 uniform concentration in each area sampled (Table 3-2b, 3-2c). 



The only metals measured in the 1991 survey were Cd, Pb, and Zn (Table 3-2a). 

 The Pb concentration of sediment from 2000S was slightly higher, and Zn was in the same 

 range, as samples taken from the SOUTH reference area. Lead in sediment from WLIS- 

 REF was approximately the same as at EAST, while Zn was slightly lower (Table 3-2a). 

 Measured levels of Cd in the 1991 samples were within or below the detection limits of the 

 1992 analyses. 



Pesticides and PCBs. Only two replicates from the six WLIS samples resulted in 

 detectable concentrations of any pesticide: 4,4'-DDD and 4,4'-DDT were detected at slightly 

 above the detection limit (15 ppb) in two replicates of the EAST station (Table 3-3). No 

 other pesticides were detected. Total PCBs were detected in every replicate sample, ranging 

 from 25 to 47 ppb in EAST replicates, and 3 to 61 ppb in SOUTH replicates. Pesticides and 

 PCBs were not measured in 1991 reference station samples. 



PAHs. Most of the PAH sample results from the WLIS 1992 samples wrt qualified 

 ("J") as estimated for results that were above the instrument detection limit and be'ow the 

 practical quantification limit (PQL). These data were acceptable, but a greater degree of 

 uncertainty was associated with these values than with unqualified data. 



PAH results were separated into low molecular weight (LMW) and high molecular 

 weight (HMW) compounds (Table 3-4). Means were calculated for comparison purposes; 

 detection limits were used in calculations using data below detection. Average LMW PAH 

 concentrations ranged from 30 to 170 ppb. Phenanthrene was the most abundant LMW PAH 

 compound at both SOUTH and EAST. Two replicates at EAST and SOUTH were below 

 detection in acenapthene, and one replicate of SOUTH was below detection in fluorene. 

 Average HMW concentrations ranged from 187 to 843 ppb. Three HMW PAHs 

 (dibenzo(a,h)anthracene, benzo(g,h,i)perylene, and indeno(l,2,3-cd)pyrene) were undetected 

 in all replicate samples except for one replicate from SOUTH (Table 3-4). 



Both LMW and HMW PAHs were analyzed in reference station samples from 1991 

 (Table 3-4). In general, WLIS-REF PAH values were within or slightly higher than the 

 EAST station ranges. PAH values at 2000S were elevated for many of the compounds 

 measured compared to SOUTH values. The sum of LMW PAH concentrations in sediments 

 from 2000S was approximately three times that of the SOUTH replicates, and the sum of 

 HMW PAHs was approximately twice that of SOUTH. 



Monitoring Cruise at the Western Long Island Sound Disposal Site, July 1992 



