As crude oil continues to leak from a giant oil rig that sank last week in the Gulf of Mexico, officials have begun burning some of the petroleum in an effort to prevent it from reaching land. The giant oil slick is now less than three miles from the Louisiana coast, and officials say it will inevitably reach the shoreline, likely by some time Friday.
While purposely igniting the oil may seem extreme, experts say its advantages far outweigh its drawbacks. “Once you have a spill, all of the options are bad,” says Jeffrey Short, who spent decades studying oil spills as a chemist for the National Oceanic and Atmospheric Administration (NOAA) and is now Pacific science director at Oceana. “The challenge is to find out what is the least bad.”
Despite obvious downsides like the air pollution it releases, burning up leaked oil tends to be one of the better options. While other response methods are generally 10 to 20 percent effective at recovering oil under ideal circumstances, burning can reduce it by 50 percent or more, Short says.
In the gulf, where the wind is pushing the oil slick closer to the particularly sensitive Mississippi River Delta region, cleanup crews conducted the first burn late Wednesday afternoon and deemed it successful. A small part of the spill was collected within a 500-foot boom (floating barrier), towed away from the rest of the spill to prevent spread of the fire, and ignited. Additional burns will likely be conducted in the coming days, weather permitting.
In the open water, the oil is hazardous to wildlife that may come in contact with it or ingest it. Sea turtles (many species of which are already endangered) and marine mammals such as whales that live in the gulf can get exposed to the oil when they surface to breathe. Worse yet, the spill could kill the chemically sensitive larvae of fish and other marine species, leading to a low reproductive yield, says Jacqueline Savitz, Oceana’s senior campaign director.
But the impact could be even more severe when the oil hits shore, both because of the wildlife at risk and because the cleanup process could become far more difficult. Intertidal areas are more biologically active than the open ocean, and at this time of year migratory birds may also be passing through and landing on the slick. Once a bird’s feathers get covered in oil, the animal loses its ability to regulate its body temperature and can die of hypothermia. According to Christopher Reddy, a marine chemist at Woods Hole Oceanographic Institution, contamination of wildlife is particularly bad because the consistency of crude oil is thick and sticky, comparable to peanut butter, and can literally smother small animals.
The situation would worsen further if oil penetrates the barrier islands of the Delta region and gets into the estuaries behind them, which are extremely biologically rich and very sensitive. Should that happen, the oil could be nearly impossible to clean up without destroying the wetlands in the process.
Meanwhile, NOAA scientists have discovered a third leak from the damaged riser (the pipe that carried oil from the well to the surface) and upped their estimate of the leak’s magnitude by fivefold, from 1,000 barrels (42,000 gallons) to 5,000 barrels (210,000 gallons) a day. Crews are pursuing several strategies in hopes of curbing the flow as quickly as possible. Efforts to use remote-controlled vehicles to engage the blowout preventer, a massive valve designed to cut off oil flow from the well, have been unsuccessful so far. Equipment has been put in place to drill a relief well that could be used to clog the leaking well with concrete, mud, and other materials, but that could take months. Perhaps most promising is a plan to place domes over the leaks to collect the oil and pipe it to the surface for collection, but that could take several weeks to implement, and is a strategy that hasn’t been tested at these depths.
“Every oil spill is different, and we still don’t know—by a long ways—all there is to know about what oil does once it’s released into the environment,” Short says. But one thing is for certain: the impacts of the current situation will become much more difficult to contain once the oil begins washing up on shore.