Salvage workers began floating the wreck of the Costa Concordia on Monday, more than two years after the cruise ship hit a reef and partly capsized off a Tuscan island.
Technicians began working to raise the ship about six feet by pumping air into tanks attached to it, said a spokeswoman for the ship’s owner, Costa Crociere.
The Costa Concordia had come to rest on its side after the wreck, but workers involved in the salvage righted the 300 yard, 114,000-ton vessel in September. It has been sitting partially submerged on steel platforms off the island of Giglio since then.
“The critical phase is most certainly when the ship rises off the platforms,” said Franco Gabrielli, head of Italy’s Civil Protection Department, which is overseeing the salvage.
The operation has been a major engineering effort, given the size of the ship and the risk of toxic leaks.
In an operation expected to be completed within a week, the Costa Concordia will be refloated and towed more than 30 yards out to sea. There it will be anchored and the last of its 30 air tanks will be put into position for a voyage to Genoa, its home port, for dismantling.
“Never before has a similar operation been undertaken,” said Michael Thamm, chief executive of Costa Crociere, a subsidiary of the U.S.-based Carnival cruise line.
The Costa Concordia wrecked Jan. 13, 2012, after the ship was steered too close to Giglio in an alleged stunt by Capt. Francesco Schettino. Thirty-two of the 4,229 people onboard were killed, and a diver also died during the salvage.
The refloating of the ship is being led by Nick Sloane from a control room on board the Costa Concordia.
“The weather is good,” he said Monday. “We must use it to raise the ship off the platforms. We hope that the ship can be stabilized by this evening.”
Because of the risks involved, the operations were repeatedly stopped to check the condition of the ship and the pressure the sea was placing on it. Environmentalists say they are worried that the wreck could break apart.
When the last of the air tanks are installed, they will raise the Costa Concordia from having more than 30 yards of its hull under water to having more than 17 yards of its hull in the sea.
Four tugboats and 10 escort ships are then to take the Costa Concordia to Genoa, where it is to be scrapped over the next two years.
The voyage is expected to take several days because the Costa Concordia will be traveling very slowly.
Schettino is standing trial on charges of manslaughter and abandoning ship during the accident, which cost Costa Crociere 1.5 billion euros (2 billion dollars).
Four crew members and a Costa Crociere executive pleaded guilty to manslaughter in July 2013 and were given suspended jail sentences under plea bargains, leaving the captain as the only defendant facing a full trial.