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Gulf of Mexico the water deballast system pumped the proposed ree? ng site. The tow route with ROV assistance.

water out of the provisional ballast tanks. was pre-surveyed several months ahead This methodology sets precedence for

Submersible pumps and deballast hoses of the tow to verify information obtained other ? oating structures nearing the end were preinstalled into provisional ballast from public databases as well as to of their design life. Valuable experience tanks, and a generator was transferred account for any seabed objects or anoma- was gained, not only for the companies to the top of the hull after the topsides lies. With some convenient seas assisting involved with the ree? ng of Red Hawk were removed to power the pumps. After from the stern, the tow lasted less than but for the offshore oil and gas industry mooring lines were disconnected and two days. as a whole. Paramount to the entire oper-

Once at the ree? ng site, the tugs temporarily laid on the seabed, com- ation was the very high safety standard recon? gured into their station keeping pressed air was then pumped into the achieved. arrangement. The crew was transferred variable ballast tanks from the DB50 to to the spar to vent the air from variable raise the hull to the 400ft draft. Since Dusan Curic served ballast tanks until the spar was sit- the windlass and work chain were no as the project ting ? rmly on the seabed in a vertical longer available, the DB50 assisted in the manager for position. A highly skilled rope access mooring disconnect by lowering each InterMoor for four crew was then transferred to the spar to top chain through the chain stopper with years and has more prepare the hull for the ree? ng opera- its crane. Once the Kirt Chouest hooked than 10 years’ tions. Once complete, all air valves for into the top chain below the surface, an experience in the oil variable ballast tanks were left open

ROV cut a sacri? cial sling and the AHTS and gas industry. and the crew transferred back to the vessel laid each line on the bottom for Curic previously worked as an engineer-

DB50. One tug disconnected from the recovery after the hull was towed from ing project manager and assistant project hull and the other two pulled in the the ? eld. manager where he was responsible for developing engineering plans, approving planned ree? ng direction until the hull

Towing and ree? ng engineering deliverables and managing began to free ? ood. The hull gradually

The 70mi tow route from Garden Banks engineers and designers from various pivoted around the bottom edge of the 876 to Eugene Island 384 was laid out to disciplines. Curic received a master’s two cells and in less than 10min it laid minimize pipeline crossings, maximize degree in mechanical engineering from on the bottom in a horizontal position. the hull’s distance from other platforms, the University of Novi Sad, Serbia, and in

During the sinking the tugs powered off and maintain adequate bottom depth ocean engineering from Florida Atlantic and paid out work wires, which were clearances during the ? nal approach to University. then disconnected from tow rigging

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E-mail: [email protected] www.scanjet.se oedigital.com May 2015 | OE 115 112_OE0515_Geo3_InterMoor.indd 115 4/20/15 10:02 PM