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indicate that the overlaying cap material is comprised basically of two sediment types. The 

 CDM released over the western side of the mound (Stations MQR-2, MQR-3, MQR-8, 

 MQR-9, MQR-10, and MQR-11) is composed mainly of sands, while the surface sediment 

 collected over the eastern side (Stations MQR-1, MQR-4, MQR-5, MQR-6, and MQR-7) 

 consists mainly of fines. 



The supplemental cap material placed over the MQR mound originated from several 

 small dredging projects along the Long Island Sound coast during the 1993/94 disposal 

 season. Dredged material from six separate areas was transported to CLIS and deposited 

 at the CD A buoy ft-om October 1993 through May of 1994. Upon review of the DAMOS 

 disposal logs, distinct patterns of deposition around the CD A buoy were observed for each 

 project. 



The UDM dredged fi^om the inner basin of the US Coast Guard facility in New 

 Haven Harbor in October 1993 was composed of silts and clays, while the CDM excavated 

 from the access charmel was found to be predominantly sands and pebble. All of the US 

 Coast Guard material (21,000 m^) tended to be deposited on the northern and western sides 

 of the buoy, producing a coarser surface layer. Sediment removed from the Lex Atlantic 

 Gateway terminal (21,500 m^ of sand, silt, and clay) was reportedly deposited south and 

 west of the CD A buoy. As a result of the consistent disposal barge approaches for the 

 larger volumes of CDM, in conjunction with the placement patterns of smaller volumes of 

 sediment from Pine Orchard Yacht Club (16,500 m^), Pootamck Yacht Club (4900 m^). 

 Breakwater Key Inc. (2000 m^) and Guilford Harbor (650 m^), the material deposited over 

 the MQR mound became segregated. 



Average grain size values developed from the 1 1 grab sampling stations over the 

 MQR mound are very similar to CLIS-REF in terms of percent gravel, sand, silt, and clay. 

 Comparison of the average MQR grain size results to the 4500E and 2500W reference 

 area averages shows that the MQR mound had a slightly higher percent sand content and a 

 lower percent silt and clay fraction than these two reference areas. When comparing the 

 individual results for the eastern area of the mound, it is found that this side is similar in 

 grain size to the 4500E and 2500W reference areas. In addition, the average total organic 

 carbon ( % TOC) content of the MQR mound surface sediments was comparable to the 

 reference areas. Individual TOC values tended to be more variable for the MQR mound 

 than the reference areas due to differences in sediment types over the mound surface. 



The July 1994 REMOTS® photographs also indicate that the area is recovering well 

 from the latest disposal. The recolonization rate suggests that the MQR mound is quickly 

 establishing a stable, healthy benthic community within the newly deposited sediment 



Monitoring Cruise at the Central Long Island Sound Disposal Site, July 1994 



