Ocean Pollution from Strange Sources
Almost immediately after the cruise ship “Costa Concordia” went off course and capsized after a rock tore through its hull on January 13, 2012, questions were raised on the potential of an environmental disaster in the clear and pristine waters off the small Isola del Giglio in Italy. There were almost 2,400 tons of heavy fuel oil on board, in addition to mechanical lubricating oils, 10 large tanks of oxygen, and 3,929 liters of carbon dioxide. Although the heavy fuel oil was successfully removed from the ship relatively quickly after the initial crash, the inventory list indicates the Concordia was carrying liters of oil lubricants, paints, insecticides, glue, and paint thinners, all of which remain on board.
The wreck can be seen on Google Earth off the coast of Giglio
Earlier today, the largest maritime salvage operation ever began in an attempt to right the 114,000-ton Concordia so it can be moved away from the island, cut and salvaged for parts. As the operation commences, concerns persist about the “toxic stew” that remains on board, which could cause devastating effects on the surrounding waters if the compromised hull breaks in the salvage process and leaks begin.
The wreck lies within the Pelagos Sanctuary for Mediterranean Marine Mammals, one of the Specially Protected Areas of Mediterranean Importance – areas that have been designated as such for their importance in conserving biodiversity in the Mediterranean. These areas may contain ecosystems specific to the Mediterranean, habitats of endangered species, or may be of special interest in scientific, cultural, or educational fields. The Pelagos Sanctuary is an important area for biodiversity as well as an important economic resource for the nations surrounding it – including the small island of Giglio. The island depends heavily on ocean-based ecotourism, and an environmental disaster from the Concordia could have a devastating impact on the local economy as well as the pristine waters around the island. The area has uniquely high levels of primary production, the base of diverse marine ecosystems, allowing for high biodiversity and large numbers of krill and other zooplankton that attract various predators to the area – including marine mammals. Striped dolphins and endangered fin whales are the two most commonly spotted marine mammals in the area, though it is home to many species of whales and dolphins and is a historical habitat of the critically endangered Mediterranean monk seal (though monk seals were extirpated from the Sanctuary area in the mid-20th century, there is hope for re-colonization, and vagrants have been spotted within its boundaries).
Mediterranean monk seal
Stand-by oil response vessels have been on site since shortly after the wreck occurred, and will remain throughout the salvage operations, and it is hoped that any escaping oils will be contained by oil booms that have been in place for months.
In addition to the remaining oil and other chemicals on board, the unique situation of a wrecked cruise liner has the potential to be a pollutant source from what is not usually considered in shipwreck cases – food. Freezers and refrigerators from 5 large restaurants and more than a dozen kitchens have been sealed for over a year and half without power, containing enough milk, eggs, cheese, meat, and vegetables to feed the 4,200 people on board. Since the Concordia wrecked on the first day of her trip, after barely 3 hours at sea, the amount of food on board was at its maximum: 1,268kg of chicken breasts, 8,200kg of beef, 2,460kg of cheese, and 6,850 liters of ice cream have been rotting and spoiling on board the Concordia since it wrecked, and cooking oils from the kitchens may spill into surrounding waters.
The impact of tons of food spilling from the wreck may not be all bad – food that was not trapped on board was quickly consumed by animals in the days after the wreck, providing an initial feast for sea life and the local colony of gulls. Local fishermen reported that fish seemed larger and harder to catch after the wreck, but after months of decay, what may spill out now will most definitely have detrimental consequences on the Sanctuary, though it is hard to predict exactly what effects are possible. A recent molasses spill in Hawaii had devastating effects on the local environment, essentially suffocating the entire area. The sudden influx of nutrients could cause an unusual growth of algae, and without grazers present to trim it, this could change the dynamics of the area completely.
Hopefully, the salvage of the Costa Concordia will not become a “second ship wreck,” and will be righted and moved with no incident and minimal leakage. Once upright, there will be more effort to remove anything toxic remaining inside, and the damaged hull will be repaired enough to tow the ship to its final port, leaving the surrounding waters of the Pelagos Sanctuary clear and dairy-free.