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New Ycrk/New Jersey to assess sediment remediation technology. 

 This assessment included the organization of two major, 

 international conferences with some of the world's leading 

 scientists and engineers evaluating current research and 

 demonstration programs in the U.S. and Europe. Speakers 

 represented a variety of U.S. research institutions and agencies as 

 well as organizations in the United Kingdom, Germany, Belgium, and 

 the Netherlands. A broad range of remediation approaches were 

 presented and evaluated along with the use of undersea pits for 

 sediment disposal in the ocean. A guidance document was produced 

 by a steering committee for each conference, copies of which have 

 been provided to the committee staff for your information. 



Sediment Transport 



The New York/New Jersey Harbor Estuary is a complex series of large 

 embayments, tidal straits and rivers with many diverse hydrodynamic 

 environments. Most of the approximately one million metric tons of 

 fine-grained sediments that enter the harbor annually are brought 

 there"by tributaries (i.e. Hudson, Passaic and Raritan Rivers) and 

 easily account for more than 90% of the harbor's annual 

 sedimentation rate. 



Considerable discussion at each conference centered on the lack of 

 an adequate characterization of sediment pollutant loads, 

 distribution and transport processes for New York harbor. This is 

 necessary to determine which sediments and what quantity of dredged 

 material warrant remediation. Effective decisions concerning 

 treatment technology cannot be made without this information. A 

 detailed characterization of sediments could be used to focus 

 treatment alternatives on sediment sources and depositionai areas 

 in the estuary. One useful technique for conducting this 

 characterization is sidescan sonar. This technology, in 

 conjunction with some sampling and direct characterization of 

 sediments, provides information on seafloor characteristics such 

 as bottom roughness and sediment texture at meter scales. Sidescan 

 sonar has been used successfully at other port areas tc provide 

 essential information for the design of research and monitoring 

 programs . 



Continuous measurements of current flow at several heights off the 

 bottom at selected sites will also be needed to determine patterns 

 of erosion and deposition inside and outside the harbor. 



Bioremediation 



The use of microorganisms to reduce contamination is commonly 

 referred to as bioremediation. In some cases, bioremediation 

 techniques have been used to clean up oil spills. 



