Emily Gertz reports for Talking Points Memo:
A Shell deepwater drilling site off the Nigerian coast that the company reported leaking on Wednesday may have spilled up to 2.4 million gallons, according to nonprofit environmental satellite monitoring group SkyTruth.
If so, that’s far worse than indicated in statements made so far by Royal Dutch Shell, which has put the amount of oil leaked at the Bonga offshore site at “less than 40,000 barrels,” (1.7 million gallons).
“That could mean anything from 1 gallon to 1.7 million gallons,” John Amos, founder and president of satellite-imaging nonprofit SkyTruth told TPM.
Oil must be at least 1 micron (1/1000th of a millimeter) thick to be seen from a satellite, according to Amos. The visible rainbow sheen, he says, means that the oil could be anywhere from .3 to 10 microns thick, depending on two different sets of guidelines.
Amos used an image from a European Space Agency radar satellite (the ASAR instrument) to determine that as of mid-week, the spill covered an area of 923 square kilometers (356 square miles).
So if the spill is 5 microns thick—the estimate where the two sets of guidelines intersect—the oil would add up to around 1.2 million gallons, Amos said.
Shell has stated that the spill’s thickness is mostly less than 1/100th of a millimeter, or 10 microns, a statement which leaves a big data gap as well.
“If the whole slick is, on average, 10 microns thick, that’s 2.4 million gallons,” Amos said.
Reached for comment, Shell did not acknowledge SkyTruth’s estimate, and and would only reiterate the 40,000 barrel figure.
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