i. Report 9, "Laboratory-Scale Application of Solidification/ 

 Stabilization Technology." 



2« Report 10, "Evaluation of Dredging and Dredging Control 

 Technologies." 



k. Report 11, "Evaluation of Conceptual Dredging and Disposal 

 Alternatives." 



1. Report 12, "Executive Summary." 



This report is Report 7 of the series. The results of this study were 

 obtained from conducting EFS Task 6, elements 7 and 8 (see Report 1). These 

 study results are incorporated and used in the evaluation of conceptual dredg- 

 ing and dredged material disposal alternatives described in EFS Report 11. 



Background 



3. The technical approach to the EFS is described in Report 1 of this 

 series. The study involved a series of innovative laboratory tests performed 

 on a variety of sediment types (upper estuary composite, hot spot, and compar- 

 atively clean sediment for capping) . The composited sediment sample that was 

 tested extensively for the EFS represents the top 2 ft* of sediment in the 

 upper Acushnet River Estuary and has a polychlorinated biphynel (PCB) concen- 

 tration of approximately 2,000 xng/l. The hot spot sample, which represents a 

 much smaller portion of the site, is four to five times higher in PCB concen- 

 tration than the upper estuary composite sample. The potential capping mate- 

 rial sediment sample was collected from 3 ft below the upper estuary bottom 

 along the eastern shore above the Coggeshall Street Bridge. Details on the 

 sampling, compositing, and analytical procedures are given in Report 3. Sam- 

 pling and characterization of the capping material are discussed in Report 6. 



4. One remedial action alternative being considered for the New Bedford 

 Superfund Site is hydraulic dredging with temporary or permanent dredged mate- 

 rial disposal in either an upland or intertidal confined disposal facility 

 (CDF) . The conceptual design of either facility requires an evaluation of the 

 settling behavior and properties of the dredged material to estimate the 

 storage requirements for good solids separation. Efficient removal of 



* A table of factors for converting non-SI units of measurement to SI (met- 

 ric) units is presented on page 3. 



