Work to refloat the wreckage of the Costa Concordia began on Monday.
Some 32 people died when the ocean liner slammed into rocks off the coast of Giglio, Italy, three years ago.
Two bodies – a passenger and a crew member – have never been recovered.
The Costa Concordia slammed into rocks off the coast of Giglio, Italy, three years ago
The wreck will be pulled into an upright position with hydraulic jacks, cables and compartments known as “sponsons”, welded onto its port and starboard sides, the Telegraph writes.
It is expected to be refloated by pumping air into tanks attached to the ship and then dragged by 10 tugboats to the port of Genoa for demolition.
It is believed to be one of the biggest maritime salvage operations in history and has already cost nearly one billion US dollars.
Salvage master Nick Sloane told Sky News: “The risks are that the ship could bend as it is raised, or the chains underneath it could snap.
Once the vessel has been refloated, it will be dragged to Genoa for demolition
“There will be 42 people on board during the first manoeuvre. If disaster strikes we will evacuate through emergency escapes on the bow and stern.”
The refloating operation is due to be carried out from Thursday to Saturday.
In September last year the vessel was successfully lifted off rocks in the first part of the rescue operation.
It was moved onto a platform on the seabed during the operation, believed to be the biggest of its kind.
The vessel will be refloated by pumping air into tanks attached to the ship
More than 50 huge chains and winches were used to lift the ship at a painstakingly slow speed to prevent damage to the hull.
The Concordia’s captain, Francesco Schettino, is currently on trial in Italy on a number of charges related to the sinking, including manslaughter.
The 53-year-old is alleged to have ordered the ship off its prescribed course so passengers could wave at people on the shore.
The 114,500-tonne vessel then hit a reef which Schettino claimed was not mapped.