Originally Posted by http://www.rigzone.com/news/article.asp?a_id=46310
Rita Sticks Jack-up Leg in Sea Floor, Bisso Gets It OutBisso Marine Co., Inc.|Tuesday, June 12, 2007
Continuing with the efforts to clean up Hurricane Rita damage, the Bisso Marine salvage team extracted the first of three Letourneau, Inc., 84 class leg and can sections that remain penetrated into the sea floor of the Gulf of Mexico. The 130-foot-long leg and can sections each has 425 tons of steel weight. The three 84 class leg and can sections are in 230 feet of water, and each has 82 feet of penetration.
In late 2005, while using the D/B Boaz, Bisso Marine had previously removed approximately 235 feet of leg from each of the three 84 class legs that protruded into the water column near the surface and were viewed as a possible hazard to navigation by their owner. Since early 2006, Bisso has been working in a collaborative effort with the rig owner to assemble a Bisso-designed barge having the capability to physically pull the leg and can sections from their deeply penetrated location. The 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.
With 1,600 tons of force, Barge 415 supported by the Boaz together were able to successfully stand the first 30-foot x 30-foot square 84 Class leg section from an angle of approximately 45 degrees to a completely vertical position. Once vertical, the Barge 415 applied a force of between 2,000 and 2,500 tons, depending on the sea state, until the leg and the 46-foot-diameter can were suspended in the water column clear of the sea floor. To assist the pulling efforts of the Barge 415, the Boaz conducted airlifting and jetting operations using high volume/high pressure air compressors. The operation took seven days of pulling, airlifting and jetting to stand the leg and can to a vertical position and to extract. The first 130-foot section was transported to a temporary wet storage location in the immediate vicinity until the other two sections are extracted at which time all three will be transported to a permanent reefing location.
Bisso has also mobilized several of its custom designed 10 x 6, 4 stage, "Super Jet Pumps" to the salvage location to assist in the extrication process. Each of the Bisso "Super Jet Pumps" is a self-contained, crash-caged, skid-mounted portable unit capable of delivering 2,800 GPM at 1,150 PSI at the nozzle tip. The "Super Jet Pumps" are each powered by 1,600 HP Cummins KTA50.
Bisso is under contract to extract and transport a total of 15 LeTourneau, Inc. designed legs with cans to various reef locations. The 15 LeTourneau, Inc. legs and cans are a combination of (6) 116-C Class, (3) 116 Class, (3) 84 Class and (3) 52 Class. The water depths range between 155 feet and 320 feet at five separate locations across the Gulf of Mexico.