10 



seafloor for vibracore collection. Two types of liners were used, flexible plastic liners that 

 were processed during the survey, and hard lexane liners (internal diameter of 3.5 in) that 

 were transported to a shore-based core processing facility (Section 2.2.2). Replicate cores 

 (one with a soft liner, one with a hard liner) were collected at each station. A variety of 

 core catchers and nose cones were used throughout the coring day to maximize sediment 

 recovery. In addition to personnel from SAIC, ASI, and Boston Line and Services, two 

 Massachusetts Institute of Technology (MIT) SeaGrant Program students were on-board, as 

 well as the independent observer (10, ENSR) for the Massachusetts CZM. 



2.2.2 Vibracore Collection and Processing 



Sediment cores were acquired at a total of seven stations (Table 2-1). Two 

 replicates were collected at each station from CAD-1 through CAD-5. Replicate A from 

 each was collected in a flexible liner and processed on-board, and replicate B was collected 

 in a hard liner and relocated to a shore-based core processing facility. The final two core 

 locations, CAD-6 and CAD-7, were located in areas of thicker sand as suggested by the 

 several feet of sand coating the recovered barrel. Recovery of 6A was low and a loss of 

 material was indicated, so two soft liner cores were collected at this station (CAD-6A, 6B). 

 Two cores became stuck in the sediment, so that no core was recovered at CAD-6C and 

 CAD-7 A. 



Immediately following retrieval of the vibracore at each station, the flexible core 

 liners were placed in a core cradle that was pre-marked with a scale interval (cm), being 

 careful to keep the core oriented (top to bottom). The soft liner was split open with a 

 utility knife, and the core catcher was placed at the bottom of the core. Cores were 

 described and photographs were collected every 20 cm of the core. Samples were 

 collected by MIT student observers. 



The replicate cores collected with a hard liner were removed from the core barrel, 

 carefully capped to prevent loss of sediment and/or water, marked with core numbers, and 

 "top" and "bottom" labels on the core, and stored horizontally for transport back to 

 laboratory coring facilities. Several cores were stored vertically for several hours because 

 the top of the core consisted of very fluid mud, and it was difficult to determine the 

 boundary of the sediment/ water interface. After settling, these cores were re-cut at what 

 was determined to be the interface. 



Cores were transported to the coring facilities at the Graduate School of 

 Oceanography, University of Rhode Island in Narragansett, RI. They were stored 

 horizontally in a core refrigerator for 4-7 days prior to processing. Cores liners were split 

 longitudinally using the GSO's core splitter which uses two razors to score the outside of 

 the liner. The caps were cut using a utility knife, and then a piano wire was used to split 

 the core into two longitudinal halves. One half was described, and eight samples were 



MONITORING RESULTS FROM THE FIRST BHNIP CONFINED AQUATIC DISPOSAL CELL 



