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presently adequate to the task of decontaminating large quantities of dredge material. 



6. My testimony on undersea borrow pits should not have referred to experience in Long Island Sound. The use 

 of borrow pits has been much discussed but there is very little practical experience with their use. It is thought 

 that pits can be designed so that they would provide long-term containment, however none have been in use long 

 enough to be sure there are no long-term problems. Where they have been suggested it has not been as a solution 

 but rather as a method that may have the fewest drawbacks. 



7. Greater emphasis needs to be placed on sources of sediment contamination. The management of contaminated 

 sediments must be based on fine-grid sampling of sediment contamination and a fine-grid model of sediment 

 transport for the harbor that considers both sources of contamination and sites of continuing contaminant input. 

 Sources of contamination need to be eliminated or contained and methods of reducing volume or toxicity need 

 to be fully considered before residual, contaminated material is placed at long-term containment sites. 



Remediation technology requires years of further development, demonstration and pilot-scale testing to become 

 practical and successful. Last year, $2.7 million was appropriated to the Environmental Protection Agency for 

 this purpose. Now is the time to implement a research program designed to evaluate those remediation techniques 

 with the most promise. 



Responses to questions by Chairman Solomon Ortiz 



1) At the May 4-6, 1992 Rutgers Conference on Remediation of Sediments several bioremediation processes were 

 discussed including: reduction of the toxicity of PCBs through an anaerobic bacterial transformation that removes 

 chlorine from the PCB molecule, enhancement of the rate of microbial breakdown of petroleum compounds 

 through the application of nutrients, and transformation of chromium to a less available form using sulfate- 

 reducing bacteria. In general, bioremediation uses enzymes, bacteria or other microorganisms to transform toxic 

 compounds to either less toxic or less available compounds. 



2) The use of these methods is not behind in the U.S., however developments in remediation technology are 

 proceeding sufficiently rapidly that it is necessary to keep up with developments in other countries. 

 Implementation of the provision in the 1992 Water Resource Development Act for a project to decontaminate 

 New York/New Jersey Harbor sediments will be an important step. However, a better means for testing a broad 

 range of promising bench-scale technologies with contaminated New York/New Jersey Harbor sediments would 

 be valuable. 



3) My testimony on this point is misleading. There are no tests underway in Long Island Sound and there is 

 almost no direct experience with placement of contaminated sediments in borrow pits in the New England region. 

 This statement should have referred to the use of capping techniques, not borrow pits. Borrow pits should only 

 be used if there is a much greater prospect for complete containment of material even in the most severe storms 

 than is the case for mud dumps that are not associated with pits. 



4) The most promising other approaches include land containment and the construction of containment islands. 



5) Landfill of contaminated sediments require double lined containment facilities so that there is no danger of 

 polluting groundwater, streams or adjacent coastal areas. Such a containment facility is being used presently by 

 the Port of Rotterdam for contaminated sediments. A significant fraction of the sediment may be lost in the water 

 column during dredging operations. Methods of dredging have been developed that considerably reduce this loss. 



