HOUSTON -- The Bisso Marine salvage team has extracted the first of three Letourneau Inc. 84 Class leg and can sections from the seafloor of the Gulf of Mexico. The 130-ft 39.6- m) leg and can sections became embedded as a result of Hurricane Rita. Each of the leg and can sections is in 230 ft (70 m) of water, contains 425 tons of steel weight, and has 82 ft (25 m) of penetration, the company says.
Bisso removed approximately 235 ft (72 m) of leg from each of the three 84 Class legs in late 2005. Since early 2006, the company has been working in a collaborative effort with the rig owner to assemble a Bisso Marine designed barge with the capability to physically pull the leg and can sections from their location.
Barge 415 is designed with a maximum pull of 3,000 tons over the stern and has a side lift capability of 5,000 tons. Barge 415, supported by the D/B Boaz, was able to move the first 30 ft x 30 ft (9.1 m x 9.1 m) square leg section from an angle of approximately 45º to a completely vertical position.
Once the section was vertical, the barge applied force until the leg and the 46-ft-diameter (14 m) can were suspended in the water column clear of the sea floor. The D/BBoaz conducted airlifting and jetting operations to assist the pulling efforts of the barge, Bisso Marine says.
The operation took seven days. The first 130-ft (39.6-m) section was transported to a nearby temporary wet storage location awaiting the extraction of the other two sections. when all three sections are extracted, they will be transported to a permanent reefing location, Bisso Marine says.
Bisso Marine is under contract to extract and transport 15 legs with cans from water depths ranging between 155 ft and 320 ft (47- 97.5 m) in five locations. The legs and cans all will be moved to reef locations in the Gulf.