Emergency officials managing the wreck of the Costa Concordia on Friday afternoon were facing one of their most difficult decisions since the giant cruiseliner capsized after hitting a rocky reef off the tiny island of Giglio.

Twenty-four passengers are still missing, and rescue workers are still conducting what they consider a search and rescue operation. But environmental groups are putting increasing pressure on them to call off the search and move on to a recovery mission. Such a move would pave the way for the SMIT Salvage company from Rotterdam to start securing the ship and siphoning the 500,000 gallons of diesel fuel from its tanks.

SMIT has set up an impressive worksite on the tiny island off the coast of Tuscany, with boats, cranes, and dozens of workers on the scene. A representative of the company said the salvage operation could begin at any time but that the rescue officials on Giglio prefer to wait until the search for survivors has been officially suspended.

Coast Guard spokesman Cosimo Nicastro told The Daily Beast that officials were weighing many factors before making a decision. “Theoretically, a person could survive in one of the cabins that is above the water line for days,” he said. Still, the last survivors were found on Sunday morning, 48 hours after the crash, and no one has been found alive since.

On Tuesday, the Coast Guard command said at that time only 25 percent of the above-water cabins had been searched and even less of the submerged cabins. Small explosions allowed rescue workers to search some of the lower areas, but divers have to battle floating furniture and debris that includes clothing, floating food, wine bottles, and dangerous twisted metal. They also are extremely concerned about the continuing movement of the wreckage. Rescue operations were halted for most of the day Wednesday and Friday because of the ship’s sporadic movement. “We have not yet been through the full ship,” Nicastro said. “The safety of the rescue workers has to be our primary concern as we look through the ship.”

The Concordia sits on two rock pillars over a bed of sand. There is water flow under the ship that has moved it 1.5 meters toward deeper water in the week since the crash. An official with the Coast Guard told reporters that it is moving at a steady rate of 7 millimeters a day, with sudden jolts at times. Less than 30 meters from where the ship is resting is the first of many terraced drop-offs that lead to 90-meter-deep waters. The 17 fuel tanks can withstand pressure of only 20 meters of water before bursting.

A fuel spill would flood the Giglio Archipelago, the largest marine park in Europe, comprising 150,000 acres of protected waters in which hundreds of species of marine life thrive, including giant swordfish, dolphins, and monk seals. The islands are magnets for scuba divers, snorkelers, and birdwatchers, and are home to exotic birds, butterflies, and rare frogs.

The Italian authorities have already laid booms around the wreckage in the event of any leakage from the ship and so far, they say, not a drop of fuel has escaped. Still, they are anxious to get started on the operations first to empty the fuel and then eventually refloat or cut up the ship to move it out of the area.

The family members hoping for a miracle would prefer the salvage operations are held off a little bit longer. Susy Albertini, the distraught mother of the youngest missing person, 5-year-old Dayana, who was on the Concordia with her father, William, and his new girlfriend, who survived the accident, has captivated the hearts of Italians. Albertini has spent the last week making tearful appeals to survivors to try to remember if they saw her daughter. “Dayana was such a happy child. She was looking forward to the cruise,” she told reporters. “She packed her own suitcase for the cruise with all her prettiest clothes.”

On Friday, Albertini joined a group of family members who were accompanied by the Coast Guard to take a close look at the wreckage by boat. They have been told that there is very little chance of finding their loved ones alive, but they cannot yet give up hope. “Please don’t stop looking for my baby,” Albertini pleaded on a national television program this week. “Please bring her home to me as soon as you can. Don’t stop looking.”