Deepwater Horizon's footprint actually a 'bathtub ring'
Two hundred ten million gallons is a lot of oil. So much so that four years after the Deepwater Horizon spill, it can still be seen on the ocean floor of the Gulf of Mexico.
That's according to a new study, which says the 2010 spill - the biggest oil spill in history - left what it calls a "bathtub ring" on the gulf.
The study says hydrocarbons from the oil plume of the well have contaminated an area of some 1,200 square miles in the deep waters of the gulf.
The study's lead author David Valentine spoke on how the geography of the ocean floor in the gulf, keeps the residual oil in the gulf.
"At this depth of 3,000 or 4,000 feet, it's bounded on three sides so there's no current that flushes through ... Water tends to slosh back and forth," Valentine said.
So if the water sloshes around the gulf, like in a bathtub, and takes the oil with it, it makes sense that there'd be a bathtub ring around the gulf. And it's easy to see in samples from the ocean floor.
BP has unsurprisingly disputed the study's findings, saying the researchers haven't been able to distinguish between oil from the spill and naturally occurring oil in the gulf.
But Valentine told The Times-Picayune the oil from the well was easy to trace because, "The discharge from the Macondo well simply swamped the signal from other sources in a clear and distinctive way that points right to the Macondo well as source."
BP has plenty of incentive to try to downplay the study's findings. It's still wrestling with the legal fallout of the spill as the affected gulf states try to get compensation for the damage.
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