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CHAPTER VI 

 FIELD INSTALLATION AND EVALUATION 



A. Installation at the FRF 



The newly re-assembled instrument and cradle were towed on a 

 trailer to the Coastal Engineering Research Center Field Research 

 Facility at Duck, North Carolina, in early May of 1982. An 

 installation site was chosen approximately 735 feet directly south of 

 the seaward end of the 1800 feet long research pier. This site fell 

 safely between the FRF's regular bathymmetric profile lines, allowed 

 a reasonalbe safety margin of length for cable deployment (18°/^) , 

 exhibited a relatively stable 20 foot depth contour over time, and 

 was considered to be sufficiently far from the large scour hole at 

 the end of the pier to avoid any related refraction effects. The 

 geographic location and typical nearshore bathymetry of the site are 

 illustrated in Figures VI-1 and VI-2. 



It was decided to install the DPG using the facility's 

 Coastal Research Amphibious Buggy (CRAB) marine vehicle. The CRAB is 

 a three-wheeled tripod vehicle capable of driving across the beach 



