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Questions and Answers for the Record 



Hearing Before House MM&F-OGM&OCS on 30 March 1993 



Ocean Disposal of Contaminated Dredge Material 



Question from Chairman Ortiz - The cost of alternative 

 technologies for remediation of contaminated sediments is an 

 important issue that you discussed in your testimony. What is 

 the most practical and cost effective method of managing 

 contaminated sediments? 



ANSWER Dr. Engler: The most practical and cost effective 

 approach for managing contaminated sediments encompasses a 

 two-phase process, short and long-term. The short-term solution 

 should consist of isolation of the unsuitably contaminated 

 dredged material through use of confined or contained disposal 

 facilities (CDF's) similar to those in use in a large number of 

 locations. The principal behind CDF containment is that the 

 contaminants are largely attached to the particulate sediment 

 material and that CDF's are engineered to contain and isolate 

 sediment particles. CDF's can also confine the liquid fraction, 

 if necessary. CDF's can be constructed on land, near shore or as 

 an in water facility (island) . Each of these approaches has been 

 demonstrated at numerous locations. Underwater capping on level 

 bottoms or in borrow pits or pits excavated for the contaminated 

 materials has also been shown to be effective, practical and cost 

 effective. The only long-term solution is to aggressively 

 control contaminants at their source, that includes point and 

 non-point sources, and clean-up of in-water and on-land hot spots 



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69-996 0-93-8 



