28 



The sampling zones were based on radial distance intervals of 200 m 

 (0-200 m, 200-400 m, 400-600 m) from the reported position of the U.S. Navy disposal 

 buoy (41° 16.506' N, 72° 04.797' W; Figure 2-6). In order to assess the vertical 

 stratification of the mound, both short and long cores were collected and strategically 

 sampled. Three short cores, at least 50 cm in length, and one long core, not to exceed 3.0 

 m, were taken in each of the three designated zones: inner (0-200 m), middle (200-400 m), 

 and outer (400-600 m). In addition, one short core was obtained from WEST REF each 

 year to represent ambient sediment and provide information on background contaminant 

 concentrations. 



2.4.1 Field Collections 



All cores were obtained with the use of Ocean Surveys Incorporated (OSI) Model 

 1500 pneumatic vibratory corer attached to a 1.5 m or 3 m steel barrel (9.5 cm I.D.). A 

 chemically inert, clear Lexane® liner (8.9 cm I.D.) was fitted within the core barrel, with 

 stainless steel core cutter and catcher assemblies secured to the end. Upon retrieval of the 

 coring device, the internal liner containing the sediment sample was removed from the core 

 barrel, capped, labeled, and stored at 4°C with minimal exposure to sunlight. At the 

 conclusion of the field operations, all cores were transported to the University of Rhode 

 Island Graduate School of Oceanography (GSO) laboratory facilities and refrigerated during 

 storage. 



A total of 15 vibracores were taken during the September 1997 survey: 14 cores 

 collected at the Seawolf Mound, and one core obtained from the WEST REF reference area 

 (Table 2-6). The sampling locations were labeled Station 1 through Station 13, with Stations 

 1 through 12 placed over the Seawolf Mound and Station 13 representing the WEST REF 

 sampling location (Figure 2-6). During this survey, two additional cores (2B and 3B) were 

 obtained in the outer (400-600 m) zone due to shallow penetration (less than 80 cm) of the 

 coring device on the first sampling attempts. 



The coring survey was repeated in July 1998, as a total of 15 sediment cores were 

 collected from 12 stations over the disposal site and one station at WEST REF (Table 2-7). 

 During this survey, sampling locations were designated Station 14 through Station 26, with 

 Stations 14 through 25 placed over the Seawolf Mound and Station 26 representing the 

 WEST REF sampling location (Figure 2-6). Duplicate cores were collected at two stations 

 (14 and 20) to insure adequate core-length for sampling. The second sample was collected 

 at Station 14 due to loss of the top portion of the sample, while an oblique angle of 

 penetration of the first core was cause for a second attempt at Station 20. 



Monitoring Cruise at the New London Disposal Site, Seawolf Mound 1995 - 1998 



