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TREATMENT TECHNOLOGIES 



Now I would like to discuss briefly the validity, 

 engineering aspects and costs associated with the management, 

 treatment and remediation technologies that were identified in 

 discussions with the Subcommittee staff. Many of these 

 technologies are being conducted as part of EPA's Great Lakes 

 Assessment and Remediation of Contaminated Sediments (ARCS) 

 program and are described in more detail in the document 

 published in support of EPA's ARCS program entitled, "Review of 

 Removal, Containment and Treatment Technologies for Remediation 

 of Contaminated Sediments in the Great Lakes." As requested in 

 your letter of invitation, I am describing these technologies 

 below along with a description of a few other technologies used 

 elsewhere. 



Decontamination Technologies . Many processes and 

 technologies are potentially available for dealing with 

 contaminated sediments, but few have been actually applied on a 

 field scale. Most testing of treatment technologies has been 

 done on a bench scale with limited pilot scale applications. The 

 database for design of contaminated sediment management 

 operations is primarily limited to navigation dredging and 

 limited sediment remediation projects. Further testing and pilot 

 demonstrations are needed that incorporate complete sediment 

 remediation strategies, not just individual pieces of the 

 remedial alternative. Costs for managing contaminated sediments 

 in large and possibly even small volumes will be significantly 

 more than the costs of normal dredging operations, perhaps 

 greater in cost by orders of magnitude. 



Subaqueous Capping and Borrow Pits for Contaminated 

 Sediments. In the last decade, capping techniques that limit the 

 mobility of contaminants in sediments disposed of by open water 

 methods have been demonstrated on the east and west coasts. 

 Capping has been demonstrated as a technology for disposal of 

 contaminated dredged material in near coastal waters in Long 

 Island Sound, New York Bight, Duwamish Waterway, and sediment 

 remediation projects in Puget Sound. The costs of normal 

 maintenance dredging projects ranges from $4 to $8 per cubic yard 

 (cyd) of dredged material moved. Capping could double or triple 

 those costs, depending on the availability of cap material. 



Contained aquatic disposal is an engineered method of 

 capping for shallow sites, where the disposal site is first 

 excavated to construct a pit for placement, followed by capping 

 of the contaminated material with clean material. This option 

 has been demonstrated to be feasible for contaminated sediment in 

 Rotterdam Harbor, Netherlands, and was used for a pilot project 

 for the New Bedford Harbor, Massachusetts Superfund project. Pit 

 construction costs significantly increase the total costs of this 



