2.0 DESCRIPTION OF FIELD MEASUREMENT PROGRAM 



2.1 Field Operations 



2.1.1 Field Schedule and Logistics 



Deployment, servicing, and final recovery of the moored instrumentation at the 

 Portland Disposal Site (PDS) were accomplished during four field operations. The initial 

 trip, conducted on February 27, 1996, entailed selection of a suitable site for the 

 oceanographic measurements and deployment of the instrument array. During the second 

 and third trips, conducted on April 6 and April 23, respectively, the instrument array was 

 recovered, serviced to replace batteries and acquire data from the internally recording 

 instrumentation, and redeployed. The final trip was conducted on May 14 to recover the 

 array and acquire data from the final deployment period. 



The timing and executions of field operations were highly dependent on winter 

 weather conditions, and two vessels were employed depending on availability. The first 

 two deployment/servicing cruises were conducted with assistance from the able crew of the 

 University of New Hampshire's research vessel Gulf Challenger , based at Portsmouth, 

 NH. The final two cruises were accomplished using the commercial fishing vessel Susan 

 & Caitlyn, from a home port in Portland, ME. 



2.1.2 Selection of Deployment Site for Moored Instrumentation 



During the February 27, 1996 field trip to the proposed deployment site, a brief 

 high-resolution bathymetric survey was conducted to aid in selection of the optimum 

 location for deployment of the moored array. This survey revealed a small, relatively level 

 area in the southwestern quadrant of the site that appeared suitable for deployment of 

 equipment (Figure 2-1). The target deployment site, located at 43°33.63'N, 70°02.49'W 

 at a water depth of 58 m below mean lower low water (MLLW), was approximately 

 1.5 km southwest of the location where dredged material was disposed at various times 

 during the spring 1996 measurement program. 



Although the bathymetric contours presented in Figure 2-1 illustrate smoothly 

 varying topography in the vicinity of the proposed mooring site, the actual topography was 

 extremely rough (see below), which is a reminder that considerable spatial averaging of 

 bathymetric soundings is performed in the process of generating a gridded depth matrix 

 from which bathymetric contour plots are created. 



Oceanographic Measurements at the Portland Disposal Site during Spring of 1996 



