Grounded ship Costa Concordia is expected to be raised into an upright position in September.

No official date has been set by the Italian authorities or by the two companies – Titan Salvage and Micoperi – that were awarded the recovery project, CBS News reports.

The ship ran aground off the island of Giglio on January 13 last year.

Months of work by around 500 salvage workers have suffered delays caused by the weather and complications in efforts to drill and level the uneven granite seabed.

The companies have undergone months of planning to ensure the ship is ready to be rotated into an upright position, but the next phase to remove the ship from the sea completely is unlikely to happen until next year.

Speaking to CBS News, salvage master Nick Sloane said two massive tanks had been installed on the bow of the ship to stablise the ship and reduce any chance of further damage. The tanks, which were installed last week, also provide buoyancy.

Microphones and cameras will be installed in at least five areas of the ship to allow for constant monitoring during the eight to 10 hour operation.

Sloane said: “There will be a lot of noise and it’s important that we listen to the different sections.

“We can take measures and make adjustments depending on any twist and tortion on the ship. We are confident the ship will be coming upright and know the first 20 degrees of rotation are critical. It’s going to be a long, nerve-racking day.”

Two of the 32 people killed when the Costa capsized are still missing and authorities hope to recover their bodies after the parbuckling. Officials also still need to empty the safe deposit boxes in the passenger cabins and return belongings to their legitimate owners.

Meanwhile, the trial of the ship’s captain, Francesco Schettino, is due to resume next month.

Five other members of the Costa Concordia staff were convicted of manslaughter in July and sentenced to less than three years each.