74% of BP Gulf oil leak ‘has been safely dealt with’
Three-quarters of the oil that has leaked from the Deepwater Horizon oil well in the Gulf of Mexico poses no further risk to wildlife, according to an investigation.
The finding was released as BP announced that its latest effort to seal the world's most notorious hole in the ground seems to be working, and President Barack Obama said the operation was “finally close to coming to an end”.
The finding that only a quarter of the spill poses a threat now comes from an investigation by the US Interior Department and the American National Oceanic and Atmospheric Administration (NOAA).
“It was captured. It was skimmed. It was burned. It was contained. Mother Nature did her part,” the White House energy adviser, Carol Browner, said on NBC's Today show yesterday.
The federal report, shown to The New York Times, found that most of the oil from the leak has already evaporated, dispersed or been captured or otherwise eliminated from the ecosystem, and that much of the rest of the oil is so diluted that it poses little additional harm.
“There's absolutely no evidence that there's any significant concentration of oil that's out there and that we haven't accounted for,” Jane Lubchenco, the head of NOAA, told the paper.
Based on the quantity of oil released, the disaster is thought to be the worst oil leak in history.
However, its long-term effect on marine wildlife is less easy to determine because the warm temperatures of the Gulf mean that much of the oil would have evaporated or been broken down naturally by oil-degrading microbes.
The NOAA report calculates that 74% of the oil has been effectively dealt with by capture, burning, skimming, evaporation, dissolution and dispersion.
Much of the dispersed and dissolved oil will break down naturally, although the rate at which that will occur has to be determined.
The remaining 26% of the oil “is on or just below the surface as light sheen or weathered tar ball, has washed ashore or been collected from the shore, or is buried in sand and sediments”, the report says.