- Several hundred passengers are in Giglio to commemorate the anniversary
- Costa Concordia ran aground off Italian island last year, killing 32 people
- Salvage operations are taking longer than expected
The Costa Concordia, a half-submerged carcass of a cruise liner, still sits in the harbor where it ran aground.
It looks out of place amid the calm blue waters, which belie the chaos of a year ago.
One year ago Sunday, the luxury liner struck rocks and turned on its side off the Italian island of Giglio, killing 32 people.
Several hundred survivors of that wreck and residents plan to commemorate the disaster by holding a memorial Mass and observing a minute of silence.
Also, at 9:45 p.m. local time, the moment of impact, they will light and release 32 lanterns -- one for each of the victims.
About 3,200 passengers and 1,000 crew members were on board the ship that night. Many were attending a magic show and some thought, when the lights first went out, that the sudden darkness was part of the performance.
According to passengers' accounts, chaos erupted as guests rushed to fill the lifeboats and escape the ship. Some crew members helped passengers and then jumped overboard; remaining members seemed helpless to handle the melee.
The Concordia's captain, Francesco Schettino, could face charges that include manslaughter and abandoning ship. Other Concordia executives and crew members also could face trial.
Schettino has said that managers of the cruise line instructed him to sail close to the island and has denied allegations that he was sailing too fast. He said the rock the ship struck was not indicated on his charts of the area.
Meanwhile, the liner is still sitting in the water.
More than 420 people are working 24-7 to secure it, but salvage efforts are taking longer than expected. Officials now hope to have the ship upright by late June or early July and to tow it to some port by September.
That represents a delay by a few months.
"We are working round the clock to get the job done as fast as we can," said Nick Sloane, head of salvage operations.
"There is a lot of calculating, recalculating and validating the calculations in an operation like this," he told CNN. "There is no room for mistakes."
The workers, of whom 110 are divers, live on a floating barge. There is the constant buzz of generators and drills in Giglio's harbor.
The search for two people who remain missing will continue alongside salvage operations, said Franco Gabrielli, head of the Italian Civil Protection agency.
The Costa Concordia cannot stay in its current position, as it represents a danger for the environment, said Gabrielli. A portion of Giglio's coastal waters is designated as a protected marine habitat.