GIGLIO, Italy - Salvage crews are working against time to remove the shipwrecked Costa Concordia cruise ship, which is slowly being crushed under its own weight on its perch of granite seabed off the Tuscan island of Giglio. Officials said Monday that if this attempt fails, there won't be a second chance.

Nick Sloane, the leader of the salvage operation, said the Concordia has compressed some 10 feet since it came to rest on its side on the rocky perch Jan. 13, 2012, after ramming a jagged reef when it skirted too close to the island during a publicity stunt allegedly ordered by the captain; 32 people were killed.

Sloane, an engineer for U.S.-owned company Titan Salvage, said experts would have one chance to pull the ship upright and float it away to the mainland for demolition. The attempt will probably take place in mid-September. "We cannot put it back" down and start over, said Sloane.

Sloane spoke aboard a work boat as he accompanied journalists for a close look at the wreckage on the eve of the trial of Capt. Francesco Schettino, who is charged with manslaughter, causing a shipwreck and abandoning the ship before all passengers had been evacuated.

The trial, which was supposed to get under way July 9, was postponed until Wednesday due to a lawyers strike. The Italian captain denies wrongdoing, and claims his skillful guiding of the ship after the collision helped save countless lives.

The timetable to remove the Concordia has also been pushed back. The original plan envisioned removal before start of this summer, but bad weather undermined those plans.

"We lost two months to weather," said salvage master Sloane, explaining that the season's harsh sea conditions made it risky for diving teams to work, including installing bags that are filled with cement to provide a more stable base when the flat-keeled ship is pulled upright.

Sloane said the granite seabed also proved more resistant to drilling than imagined. It was "like trying to drill through glass at a 45-degree angle."

Pressure to make the unprecedented operation succeed is mounting as experts worry that a small window of opportunity to pull off the ambitious feat could shut in a few months.

"Another winter and we might not be able to parbuckle," Sloane said, using the nautical term for righting a ship. He expressed concern that the ship might compress even further, making it impossible to pull it up upright and into a position so it can be floated away.

The project calls for dozens of crane-like pulleys flanking the ship to slowly start tilting the vessel upright at a rate of 3 meters per hour. In all, the parbuckling should take about 12 hours.

On Monday several welders moved like Spiderman on the now horizontal hull, securing steel pieces which will function like hooks. Steel chains weighing 17,000 tons are being looped under the wreck to help pull it upright. So far 18 chains have been laid, with the remaining four to be put in place over the next few days.

To work on the tilted wreck, the welders were given five days of climbing training on nearly sheer granite rocks on the island by instructors from Italy's Dolomite mountains.

Crews are also attaching caissons, or tanks, to the exposed flank of the Concordia. The caissons will be filled with water to add weight and help pull the ship upright. Identical caissons will be attached to the submerged side of the ship once it's righted. The caissons on both sides will then be filled with air to float the ship up off the rocks so it can be towed away.

The 70-meter-long gash on the Concordia's hull has been largely covered with metal plates, though an exposed 10 foot wide hole remains, resembling a truck garage entrance. Crews said there was no need to cover that remaining hole. The gash itself wasn't repaired, since engineers said it wasn't necessary. The salvage operation extracted 96 tons of granite reef from the hole, Sloane said.

Just inside the gashed area were four compartments designed to be water-tight, including engine rooms, Sloane noted.

At the very top level of the luxury liner, just over the area where the reef speared the ship like a jagged knife, was the passenger dining room.

Its big picture windows gave diners a view of the lights of Giglio as the Concordia tried to glide close to the coast, the inky blackness of a winter's night view broken only by the lights in islanders' houses.

Survivors have recounted how, many of them dressed in cocktail dresses and suits, were just sitting down for a gala first-night meal when the collision occurred, setting off panic and confusion with no quick word from the crew about what exactly had happened.

After slamming into the reef off Giglio, the ship drifted toward port, where, badly listing as it rapidly took on seawater, it capsized. Passengers described a frantic and delayed evacuation, with the bridge initially insisting to inquiring coast guardsmen that the ship had merely suffered a blackout.

Bodies of two of the victims - an Italian passenger and of a Filipino waiter - were never found.

Every day, divers "see mattresses and towels hanging from balconies. Every time they see it, they are very aware ... there are still bodies" possibly under the wreck, Sloane said. The removal projects' divers haven't gone into the wreckage; the futile search for the last two victims' bodies was conducted earlier by fire department and coast guard divers.

Franco Porcellacchia, coordinator of removal plans for Costa, which is owned by Miami-based Carnival Corp., estimated that the removal would cost about 500 million euros, paid for by insurers.

Where the wreck will be towed for demolition - assuming it can be floated away - has yet to be decided, although Italian media have mentioned the Tuscan port of Piombino as a possibility. Porcellacchia said one difficulty is finding a port that can handle the cruise ship's dimensions, which will be made even wider by the caissons that will be attached to each side.

While Giglio has fretted about losing tourists because of the wreck, the island's port bustled with vacationers Monday. And the removal has brought new business: Two hotels overlooking the wreck are booked year-round by crews.

At cafes near the port on Monday, welders in work jumpsuits and rubber boots rubbed elbows with sunbathers in shorts and flip-flops.

A bronze plaque along a harbor wall lists the name of the 32 people who perished on what was supposed to be a pleasure cruise.