Given the above disposal history, the objectives of the present survey were to 



1) assess the extent, topography, and effective coverage of cap material added to 

 the NL-TR region since the October 1988 postdisposal survey; 



2) determine the status of benthic recolonization and mound stability at the 

 inactive NL-85 disposal mound; 



3) measure the extent and topography of dredged sediment deposits at the NL-88 

 mound; and 



4) assess near-bottom dissolved oxygen concentrations relative to REMOTS® 

 benthic analyses at and near the disposal site. 



The 1990 monitoring scheme at the New London Disposal Site was designed to test 

 the following predictions: 



• Sediment disposed at the NL-85 mound would have a minimal effect on mound 

 height; possibly there would even be a decrease due to consolidation. Benthic 

 recolonization in this area would be primarily at Stage II and III. 



• Disposal at the present buoy position (Buoy 90) would have deposited new 

 material within a radius of 250-300 meters. Benthic recolonization in the 

 central portion of this region would be at Stage I, whereas the margins of the 

 mound would exhibit Stage II, III, and Stage I on II and III. 



• Near-bottom dissolved oxygen concentrations would be similar at stations 

 within the disposal site compared to stations within the reference areas. 



Monitoring Cruise at the New London Disposal Site, June- July 1990 



