Italian salvage crews say they expect to begin pumping thousands of tonnes of fuel from the wrecked Costa Concordia by Saturday.
Authorities have been increasingly concerned at the threat of an oil spill in the marine reserve but removing oil and diesel has been delayed by the search for survivors and bodies.
Early on Tuesday divers found the corpse of an elderly woman, bring to 16 the total number of bodies recovered.
With at least 16 others still missing on the vessel, Franco Gabrielli, the head of Italy’s Civil Protection Agency gave assurances that rescue work will continue to find their remains.
As work off the Tuscan island of Giglio goes on into a second week, accident investigators are now expected to focus on the Costa Concordia’s operators.
Meanwhile, the wife of the ship’s captain, Francesco Schettino, has leapt to his defence amid confusion over his toxicological tests. The 51-year-old has been accused of manslaughter and abandoning ship before the evacuation of some 4,000 passengers and crew.