FI & Power & Underwater Construction
MSF RANGE NORFOLK R6 UPGRADES (EMT REPLACEMENTS)
PMI conducted a dive survey of the underwater array to gain familiarization with the existing conditions which were 800′ long and 40′ wide, located within the Entrance Reach Channel West of the Hampton Roads Bridge Tunnel. Water depth ranged from 40 to 60 feet deep. The damaged underwater electromagnetic triaxial (EMT) sensors and associated cable were removed, and new EMT sensors, magnetometer instruments, and associated cables were installed to reach the data concentrator shed. 3,000 cubic yards of non-magnetic gravel were placed over the instrument array, followed by the placement of 9″ thick 8’x20′ articulated concrete matting over the newly laid and existing cables from the array to the data concentrator approximately 2,180 feet away. Upon completion, approximately 56,000 feet of cable was installed.
