A spill of epic proportion: The explosion of the BP-leased Deepwater Horizon drilling rig on April 20 that killed 11 workers has produced what as of late this month is officially the largest oil spill ever in U.S. waters. The leak began 50 miles off the coast of Louisiana, caused by a burst pipe that BP then failed to shut down. Official estimates now put the magnitude of the leak at 5,000 barrels of oil per day, but scientists point out that that number only accounts for the oil that BP has been able to siphon off from the spill -- not the total. Others believe the true number is at least eight times the figure released by the White House. Above, a marine biologist shows oil gathered from the mouth of the Mississippi River on May 17.
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