169 



You mentioned something about the time on when the data in 

 table 2a of your testimony was based. I would like to hear that. 



Mr. Kamlet. There is some indication that the concentrations of 

 PCB's in sewage sludge have gone down over the past several years 

 but I think it is also important to note that with respect to a 

 number of other contaminants, notably heavy metals and such 

 things as oil and grease which includes some rather dangerous po- 

 lynuclear aeromatic hydrocarbon constituents that there is reason 

 to believe that these figures and probably also the ones that Mr. 

 Schatzow referred to — although I have not seen the basis for those 

 numbers — underestimate and perhaps greatly underestimate the 

 significance of contributions from sewage sludge in relation to 

 other sources of contamination of the bight. 



I outline on page 3 of my prepared statement some of my reasons 

 for believing — and these are concerns that are shared by others in 

 the scientific community and Mr. Schatzow indicated before he left 

 that he endorsed the view that in terms of the relationship be- 

 tween sewage sludge and dredged material the two principal dump- 

 ing sources within the bight apex, that although the quantitative 

 contribution of heavy metal seems to be vastly greater for dredged 

 material that such a comparison probably significantly understates 

 the fraction of heavy metals that are biologically available in 

 sewage sludge in relation to dredged material. 



I think if corrections were made of the sort that we outline on 

 page 3, one would find that rather than representing only 8 or 10 

 percent of contaminant inputs that sewage sludge ocean-dumped in 

 the bight apex constitutes perhaps double that amount or even 

 greater. 



Mr. FoRSYTHE. How recent is the data base for this statement? 



Mr. Kamlet. The initial data base utilized in my table on page 

 2 A is the 1976 Mueller and Jeris study. Some of the PCB informa- 

 tion is based on Joseph O'Connor's more recent work but he relied 

 on PCB concentrations going back to the early to mid-1970's. 



I think there has been some significant improvement in sludge 

 quality since then in terms of PCBs. I don't think the picture is 

 quite as good for other contaminants. 



Mr. Forsythe. This is typical of the problems I have in dealing 

 with the bight. I will be back, I see my first 5 minutes is up. 



Mr. Hughes. The gentleman from Delaware. 



Mr. Carper. Thank you, Mr. Chairman. 



I would like to welcome Mr. Kamlet and Mr. Lahey to the hear- 

 ing today. I have a question about land-based alternatives. If either 

 of you gentlemen would answer I would appreciate it. 



Can industrial pretreatment in your judgment make New York 

 City or northern New Jersey municipalities' sludge clean enough 

 for at least some useful land application or composting purposes? 



Mr. Kamlet. Mr. Carper, I think the answer is yes. Clearly the 

 heavy metals that are present in the sludge are much more direct- 

 ly amenable to industrial pretreatment than contaminants like 

 PCB's and oil and grease that are more diffuse. But in terms of 

 heavy metal contamination cadmium seems to be the metal of prin- 

 cipal concern from a land application standpoint in terms of 

 human health, and I think there is good basis for believing that in- 



28-914 0—84 12 



