2.2 REMOTS® Sediment Profiling 



The REMOTS® survey was conducted at FADS on 2 February, 

 1987 to map the distribution of dredged material, evaluate 

 benthic habitat conditions, and document the process of 

 recolonization in the disposal area. Thirty-nine stations were 

 occupied on a cross-shaped grid centered on the "DGD" disposal 

 buoy (Figure 2-2) . Stations were located 100 meters apart and 

 extended 600 meters north of center, 800 meters south of center, 

 900 meters east of center, and 700 meters west of center. 

 Stations were also located in each of the guadrants at 250 and 

 500 meters NE, NW, SE, SW. Three replicate images were collected 

 at each station; stations were located so as to extend far enough 

 beyond the dispersion limits of dredged material in order to 

 accurately detect the amount of seafloor covered by the recently 

 deposited material. In addition, 34 REMOTS® images were collected 

 at the FADS soft-bottom reference station (42 ° 24. 69 ' N, 70° 32. 81' 

 W) . 



REMOTS® images were taken with a Benthos Model 3731 

 Sediment-Profile Camera (Benthos, Inc. North Falmouth, MA) . A 

 detailed description of the REMOTS® camera, its operation, and 

 the analysis of the photographs taken can be found in DAMOS 

 Contribution #60 (SAIC, 1986a) . 



2 . 3 Sediment Characterization 



Sediments were collected on 22 and 29 January 1987. In 

 order to choose the locations for collecting sediment samples of 

 the recently deposited dredged material from the Blue Circle 

 Atlantic and General Electric (GE) projects, scow logs were 

 studied to determine the volume of material and approximate 

 position of each scow load in relation to the disposal buoy. An 

 examination of the scow logs revealed that the majority of the 

 loads were deposited 50-100 m north of the disposal buoy. 

 Therefore, the sediment samples were collected within an area 

 with a radius of 100 m centered about 50 m north of the disposal 

 buoy (see Figure 2-2) . With the small volume of material 

 involved in these two projects and the great depth of water, it 

 was unlikely that all the sediment samples would in fact contain 

 material from the Blue Circle and/or GE projects. 



Single samples were collected from each of fifteen 

 stations randomly located within the pre-determined radius using 

 a 0.1 m 2 Smith-Mclntyre grab sampler. Six polycarbonate plastic 

 core liners (6.5 cm ID) were pushed into each sediment grab 

 sample and extracted. One complete core per grab was placed into 

 a bag for subseguent chemical and physical analysis by the NED 

 laboratory. The top 2 cm of the remaining five cores per grab 

 were composited and bagged separately for possible comparison 

 with the results from the complete core. The samples were kept 



