GIGLIO ISLAND, Italy -- Authorities have given the final go-ahead for a daring attempt Monday to pull upright the crippled Costa Concordia cruise liner from its side in the waters off Tuscany, a make-or-break engineering feat that has never before been tried in such conditions.
The ship capsized there 20 months ago, and Italy's national Civil Protection agency waited until sea and weather conditions were forecast for dawn Monday before giving the OK to try to right it. In a statement Sunday, the Civil Protection agency said the sea and wind conditions "fall within the range of operating feasibility."
The Concordia struck a reef near Giglio Island the night of Jan. 13, 2012, took on water through a 70-meter (230-foot) gash in its hull and capsized just outside the harbor. Thirty-two of the 4,200 passengers and crew members died. The bodies of two of the dead have never been recovered, and may lie beneath the wreckage.
Never before have engineers tried to right such a huge ship so close to land. If the operation succeeds, the Concordia will be towed away and broken up for scrap.
Salvage experts had originally hoped to right the 115,000-ton vessel last spring, but heavy storms hampered work. Crews have raced to get the Concordia upright before another winter season batters the ship against its rocky perch -- damage that would increase the chance that it couldn't be towed away in one piece.
Salvage master Nick Sloane seemed optimistic in the final hours before the operation began, saying Sunday that testing of the machinery in recent days had actually lifted the 300-meter (985-foot) ship up about 10 centimeters (2.5 inches), or 0.15 degrees. There have been concerns that the rocks of the reef on which the Concordia is resting were so embedded in the hull that the ship would resist being pulled off.
"We know that ... she is lively enough to move," Sloane told reporters.
The operation to bring the ship vertical involves dozens of crank-like pulleys slowly rotating the ship upright at a rate of about 3 meters (yards) per hour, using chains that have been looped around its hull. Tanks filled with water on the exposed side of the vessel will also help rotate it upward, using gravity to pull the exposed side down.
Once upright, those tanks -- and an equal number that will be fixed on the opposite side -- eventually will be filled with air, rather than water, to help float the ship up off the reef so it can be towed away.
Last week, the head of Italy's Civil Protection agency, Franco Gabrielli, said there was no "Plan B" if the rotation failed since there would be no other way to try again. But Sloane said he was confident the ship would withstand the stress of the rotation.
The most critical time will be the first hour or so of the operation, since that's when the ship will be detached from the reef.
This weekend, tourists and locals waded and swam in pristine waters just beyond the harbor, with the hulking wreck an ugly backdrop and reminder of the harrowing night when a few thousand people straggled ashore. Since the Concordia came to rest on its side, visitors have come to gawk at the wreck, providing the tiny fishing island a year-round tourist season it never had before.
Mayor Sergio Ortelli has asked for patience from the island's 1,400 residents during Monday's operation, which he expected would last about 10-12 hours. Ferries linking Giglio to mainland Tuscany stop running at dawn Monday, meaning teachers for Giglio's two schools were arriving Sunday night for classes.
Since the shipwreck, no major pollution has been found in the waters near the ship. But should the Concordia break apart during the rotation -- a possibility authorities describe as remote -- absorbent barriers have been set in place to catch any leaks. Fuel was siphoned out early in the salvage operation, but food and human waste are still trapped inside the partially submerged vessel and might leak out.
As a precaution, Ortelli told islanders last week that water tanks on the island would be topped up in case the water supply becomes contaminated.
Other inconveniences were expected. The island that lives off fishing and tourism sends its compacted garbage every Monday to the mainland by boat. That sanitation service will have to be re-scheduled when the port shuts down for the rotation operation, known in nautical parlance as "parbuckling."
One of the last ferries of the day Sunday brought a mix of tourists wanting to see the boat for what might be the last time on its side and many who had spent over a year preparing to bring it upright. They included Franco Ferraiuola, a crane operator who wouldn't be working Monday -- he has some time off -- but was bringing his wife to the island to watch the dramatic attempt.
He acknowledged that many of the experts were confident they could bring the ship vertical in one piece but he voiced some concern.
"There is always the unknown. Nothing is certain," he said.
In July, five Costa employees were convicted in a plea bargain of manslaughter and sentenced to less than three years apiece. Capt. Francesco Schettino, whom prosecutors accuse of pulling the Concordia off-course in a stunt to bring it closer to Giglio, is currently on trial, accused of manslaughter, causing a shipwreck and leaving the ship before all passengers and crew were evacuated. He has denied the charges and insisted the reef wasn't on his nautical charts.
Costa is a division of Miami-based Carnival Corp., the world's largest cruise ship company.