Salvage chief warns Costa Concordia could fracture Mr Sloane said there are huge challenges in rolling the 950 ft cruise liner upright and the salvage team is seeking to minimise any impact on the precious marine environment surrounding the island. Asked whether he had any fears about the operation the South African salvage expert said: "We have dealt with them in the best way possible - by conducting serious evaluations and putting in place all the possible technical and engineering measures." The ship is twice as heavy as the Titanic and lies impaled on two giant outcrops of undersea granite with a 160-foot gash in its hull. The scale of the operation is unprecedented engineers have constructed a huge artificial seabed beneath the 114,500 tonne ship, on which it will be rolled upright. Earlier this year the operation was delayed by bad weather and the challenges of drilling into the granite seabed to secure anchor blocks and pylons. Mr Sloane said explosives could not be used because of the quantity of chemicals and pollutants inside the vessel as well as its precarious position. When the ship is rotated, debris and dirty water is expected to pour out of its interior. "With explosions there would have been a greater risk of it slipping," he said. And let's not forget that the bodies of two people are buried inside. Pulling the semi-submerged ship upright is just the first phase of the salvage operation. The next stage is to attach giant steel compartments to the formerly submerged side of the vessel to help refloat it before it can be towed away but that is unlikely to take place before the spring of 2014.