EXECUTIVE SUMMARY 



Most of the material dredged from New England's waterways and harbors is 

 deposited in nine offshore disposal sites. The offshore disposal of the dredged material must 

 be properly managed to ensure no unacceptable adverse impacts to biota in the marine 

 environment. The Disposal Area Monitoring System (DAMOS) Program provides this 

 management control. The DAMOS Program includes field monitoring of the disposal sites 

 as well as additional tasks that contribute to the overall management of the DAMOS 

 Program. Operated by the US Army Corps of Engineers, New England Division (NED), 

 DAMOS has been in existence since 1977. The last summary of the DAMOS Program was 

 published in 1984. This report summarizes the program efforts from 1985 to 1990. 



The DAMOS Program monitors nine offshore dredged material disposal sites from 

 Long Island Sound to the Gulf of Maine: Central Long Island Sound Disposal Site (CLIS), 

 Western Long Island Sound Disposal Site (WLIS), New London Disposal Site (NLDS), 

 Cornfield Shoals Disposal Site (CSDS), Portland Disposal Site (PDS), Rockland Disposal 

 Site (RDS), Cape Arundel Disposal Site (CADS), Massachusetts Bay Disposal Site (MBDS), 

 Buzzards Bay Disposal Site (BBDS), and several special-use sites. In 1990 field work was 

 conducted at CLIS, WLIS, NLDS, CSDS, CADS, MBDS, and BBDS. Additional nonfield 

 work has included verification of the DAMOS Capping Model, management of the DAMOS 

 database, integration of the Geographic Information System (GIS) with dredging and disposal 

 site information, and the development of a tiered monitoring plan by the DAMOS Technical 

 Advisory Committee (TAC). 



Continuous monitoring of the nine dredged material disposal sites has shown that, in 

 most cases, (1) disposal mounds are stable over time, (2) there is minimal transport of 

 material away from the site, and (3) organisms did not take up significant levels of 

 contaminants. Stable disposal mounds with no off site transport are found at containment 

 sites. Eight of the nine disposal sites are containment sites where material is expected to stay 

 in the area. The only noncontainment, or dispersive, site is CSDS. At CSDS, material is 

 expected to leave the site, and it is managed so as not to adversely effect the marine 

 environment. 



Site-specific adjustments in management have been needed at NLDS since 1984. At 

 NLDS, a capping project required dredged material to be spread evenly over an existing 

 mound. Multiple points on the mound were chosen as target release points with the plan that 

 the randomness inherent in the disposal operation would result in an even distribution of the 

 sediment. The cap material formed discrete mounds with less spreading over the base 

 mound than expected. As a result of this finding, additional material was directed to this 

 location to augment the cap. 



