Yosemite-sized 'bathtub ring' of oil still left from BP Deepwater Horizon spill

Justice Department prosecutors secured new indictments Wednesday against a former BP engineer and a former BP executive charged separately with obstructing probes of the company's 2010 oil spill in the Gulf of Mexico. (Photo: The Deepwater Horizon oil rig burned on April 21, 2010).

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U.S. Coast Guard/Getty Images

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A support ship related to the collection of oil from over the site of the BP Deepwater Horizon oil well transitions through a sheen of oil as workers try to stem the flow of the oil spill in the Gulf of Mexico off the coast of Louisiana.

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SAUL LOEB/AFP/Getty Images

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Veterinarians clean an oil covered brown pelican found off the Louisiana coast and affected by the BP Deepwater Horizon oil spill at the Fort Jackson Oiled Wildlife Rehabilitation Center in Buras, Louisiana

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Saul Loeb

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There's still much oil left to clean from the BP Deepwater Horizon spill that killed 11 people four years ago, according to researchers from UC Santa Barbara and UC Irvine who recently did a survey of the damage.

It's been four years since the BP Deepwater Horizon spill in the Gulf of Mexico.

You'll remember the images of oil soaked birds trapped in the sludge and clean up crews walking along the shoreline covered head to toe in white protective suits. Eleven people lost their lives in the accident as an estimated 5 million barrels of oil gushed into the sea for almost three months.

But years later, BP still hasn't cleaned up the mess. That's the assessment of researchers from UC Santa Barbara and UC Irvine who recently did a survey of the damage. They found a 1,200-square-mile "bathtub ring" of oil on the ocean's floor. That's about the size of Yosemite National Park.

Dave Valentine is lead author of the study and geochemist at UC Santa Barbara and he joins the show to talk more about it.