Long Island Sound sediments within predefined reference areas has comphcated this 

 process. 



From 1991 to 1993, reference areas EAST, WLIS-REF, and 2000S in the vicinity 

 of WLIS have been abandoned due to detection of the presence of dredged material (Eller 

 and Williams 1996; Charles and Tufts 1996). The July 1996 REMOTS® survey over the 

 current WLIS reference areas (2000W, SOUTH, and SW-REF) found evidence of historic 

 dredged materials at reference area 2000W, an area utilized since 1987. The presence of 

 dark, reduced sediments and methane gas bubbles indicate the sediments are not 

 representative of the ambient sediment, free from the effects of anthropogenic activity. 

 These are generally isolated patches of historic dredged materials that are not detected by 

 the previous sampling conducted at reference areas. 



The specific objectives of the July 1996 Western Long Island Soimd Disposal Site 

 monitoring cruise were to 



• docimient and delineate the changes in bottom topography in the area of 

 concentrated disposal since July 1992; 



• assess the benthic recolonization status of the G and H mounds, as well as two 

 stations on the southern flank of the historic D mornid, relative to three 

 reference areas surroimding WLIS; and 



• conduct a qualitative analysis of the newly defined southwest reference area 

 (SW-REF). 



The July 1996 field effort at WLIS tested the following predictions: 



1 . The past four years of disposal activity at WLIS will result in the formation of 

 two new discrete sediment mounds (G and H), while the older WLIS F mound 

 will display significant accumulation of new material since 1992. 



2. Benthic recolonization at the H mound will be in the early stages of recovery 

 with a Stage I assemblage predominant on the moimd surface. Evidence of 

 Stage I, II, and III activity will be displayed in the surficial sediment layers of 

 the WLIS G mound. The southern flank of the D moimd (Stations D200S and 

 D300S) will show improvement in benthic conditions relative to previous 

 surveys. 



3. Seasonal hypoxia in the western Long Island Soimd region is not expected to 

 affect the results of the benthic community assessment due to the timing of 

 survey operations. 



Monitoring Cruise at the Western Long Island Sound Disposal Site, July 1996 



