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approaches and results of these studies have been presented at several 

 recent scientific meetings and to EPA' s Narragansett Laboratory research 

 staff and have been submitted to peer reviewed technical publications. 



An extensive laboratory program has been completed with chemical 

 analysis and toxicity and bioaccumulation testing of sewage sludges 

 from each of New York City's 12 wastewater treatment plants. This test 

 program has shown that the toxicity of sewage sludges to marine organisms 

 is relatively low. We are currently finalizing a sewage sludge disper- 

 sion model, and, based on preliminary results, it appears that most of 

 the City's 12 sewage sludges will meet the limiting permissible concen- 

 tration requirement of the regulations. Laboratory tests have also shown 

 no evidence of significant bioaccumulation in organisms due to exposure 

 to sewage sludge in seawater. Thus, it appears that sewage sludge from 

 most, if not all, of New York City's waste water treatment plants will 

 satisfy the environmental criteria of the regulations for ocean disposal. 



Until the Sofaer decision, EPA interpreted their 1977 regulations to 

 preclude ocean dumping of any materials which did not meet the environ- 

 mental criteria without regard for the impacts of alternatives to ocean 

 dumping. However, our studies have shown that most, if not all, of New 

 York City's sewage sludges may qualify for special permits under the 

 stringent interpretation of EPA' s regulations even without the need to 

 demonstrate that the impacts of the alternatives to ocean disposal would 

 be greater. 



As part of establishing the need for ocean disposal, the Special Permit 

 Application will also include a multimedia human health risk assessment, 

 that will compare the relative risk to man from ocean disposal at the 

 12-Mile Site and from New York's long-term, land-based sludge management 

 option, which is incineration. The preliminary results of this 

 assessment show that ocean disposal presents a lower human health risk 

 than New York's long-term land-based alternative. 



