presence of dredged material. Prior to the field operations, 

 examination of disposal logs revealed the possibility that 

 approximately sixteen barge loads of dredged material 

 (approximately 50,000 m 3 ) may have been deposited in each of the 

 two areas. These two areas, referred to as Ghost Site 1 and Ghost 

 Site 2, were surveyed using precision bathymetry, side scan sonar, 

 and REMOTS® photography to determine whether dredged material was 

 present and therefore verify if errant disposal had occurred. 

 Ghost Site 1 was located on the eastern margin of the CLIS disposal 

 site; Ghost Site 2 was located on the northern edge of the site 

 (Figure 1-1) . 



Sampling was also performed during the 1986 survey to 

 determine the concentrations of selected chemical constituents in 

 sediments from each of the ten disposal mounds and the new 

 reference station. Grab samples were obtained at the center of 

 each mound, and additional samples were taken at the STNH-N mound 

 at previously determined transect stations for comparision with 

 earlier chemical data. All samples were divided into Top (0-2cm) 

 and Bottom (2-10cm) samples in order to assess any contaminant 

 concentration variations that might occur with depth. 



Another objective of the survey was to collect grab 

 samples at each disposal mound and the new reference station for 

 analysis of benthic community structure. Only the samples from the 

 FVP, MQR, STNH-N mounds and the reference station were analyzed; 

 the rest were preserved and archived. These mounds were chosen 

 because STNH-N was found to have a different grain-size than the 

 surrounding bottom, MQR was the only mound not affected by 

 Hurricane Gloria, and FVP had long-term benthic data for 

 comparision. 



A final objective was to assess whether bioaccumulation 

 of chemical contaminants had occurred at the FVP, MQR, STNH-N and 

 CLIS-86 mounds based on comparison of contaminant body burden 

 concentrations in organisms collected at the mounds versus those 

 collected at the new CLIS reference station. Body burden levels 

 at the FVP mound were compared with past data. Organisms were 

 collected at MQR because this mound had shown anomalous benthic 

 recolonization rates and different benthic community type compared 

 with all the other CLIS mounds. The STNH-N mound was sampled to 

 provide baseline data to assess the effectiveness of a sand cap for 

 long term isolation of chemical contaminants from colonizing 

 benthos. 



2 . METHODS 



2 . 1 Navigation 



The precise navigation required for all field operations 

 was provided by the SAIC Integrated Navigation and Data Acquisition 



