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in the late 1970 's and the termination of General Electric 

 Company's discharges of PCBs to the upper Hudson River in 1977, 

 the current levels of PCBs in sewage sludge and dredged material 

 are lower than previously estimated. The City's consultant 

 prepared their estimates from analyses conducted during 1982 on 

 multiple sludge samples from each of the City's 12 water 

 pollution control plants, in contrast to the single Wards Island 

 sample from the mid-1970' s used by Bopp et al . (1981). Details 

 of the consultant's sludge analyses will be presented in the 

 City's Special Permit Application. 



Swanson et al. (1982) cited a PCB contribution of 19-26 p)ercent 

 -from sewage sludge and referenced it to o' Conner et al . (in 

 press). The City's consultant is unable to comment on this data 

 until this reference is published and can be reviewed. However, 

 one pertinent observation can be made at this time: in a more 

 "recent draft of the Swanson et al . (1982) paper (dated February 

 1983), the estimates from O'Connor et al . (in press) have been 

 deleted and the estimates from the City's consultant are 

 included. Swanson et al. (1983) cite these data as "recent 

 encouraging information which indicates that the decreased usage 

 of PCBs in the late 1970s may be showing beneficial results." 

 Swanson et al (1983) further state that "If these [recent] PCB 

 concentrations represent a consistent decrease for all 20 [New 

 York metropolitan area] treatment plants, the percentage 

 contribution of PCBs in ocean-dumped New York - New Jersey 

 sewage sludge is now comparable to that of other contaminants in 

 these sewage sludges (i.e., within the 3-12% range)." 



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