PART V: CONCLUSIONS 



66. Based on the results of the settling and chemical clarification 

 tests, it is concluded that: 



a. Settling tests for the upper estuary composite, hot spot, and 

 potential capping sediment samples exhibited zone settling 

 behavior typical of other saline sediments tested. 



b. The hot spot sediment is not expected to densify to as great a 

 solids concentration in a confined disposal facility as the 

 upper estuary composite or potential capping sediments. 



£. Effluent total suspended solids concentrations after 24 hr of 

 settling under laboratory conditions were 140, 151, and 

 150 mg/£ for the upper estuary composite, hot spot, and poten- 

 tial capping sediment samples, respectively. 



d. Chemical clarification using polymer addition is a potentially 

 effective treatment process for removing suspended solids from 

 CDF effluents generated by disposal of New Bedford Superfund 

 Site dredged material. Additional suspended solids removal by 

 the addition of Magnifloc 1586C was 82 percent in laboratory 

 jar tests. 



e. Low-viscosity, highly cationic emulsion polymers were found to 

 be the most effective, economical, and simplest to use for a 

 simulated New Bedford Harbor site effluent developed by using 

 the upper estuary composite sediment sample and estuary site 

 water. 



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