Believe It or Not, the Deepwater Horizon Oil Spill Was Even Worse Than Previously Thought

Yves here. We provided a great deal of coverage on Deepwater Horizon, aided considerably by a petroleum engineer who gave detailed explanations. We were on the downbeat side. As too often happens, we weren’t downbeat enough.

This piece curiously omits the fact that the dispersant that BP used, corexit, actually made matters worse, both by being toxic and on top of that, not doing much to break down the oil. See here, here, and here for more detail.

After the Deepwater Horizon explosion in the spring of 2010, oil poured into the Gulf of Mexico for nearly three months straight, resulting in the worst offshore oil spill in U.S. history. More than 200 million gallons of light crude flowed into the sea, devastating marine life and fisheries.

Ten years later, scientists are still uncovering new facets of the disaster and its aftermath. A study published Wednesday from researchers at the University of Miami found that fisheries closed by federal and state agencies after the spill only accounted for about 70 percent of the actual extent of the toxicity that emanated from the drilling platform. The closures were based on satellite images of so-called surface slick — the visible oil on the surface of the water. This metric was ultimately not sensitive enough to capture lower concentrations of oil that nevertheless were still harmful to animals.

“It’s a pretty interesting finding, and it shows that the surface slick is not a sufficient indicator of the real footprint of where the damage is occurring,” said Cameron Ainsworth, a fisheries oceanographer at the University of South Florida who was not involved in the study but has collaborated with its authors on related research.

Igal Berenshtein, a postdoctoral fellow at the University of Miami and lead author of the new study, said he originally set out to look at the effect of fishery closures on communities in the Gulf. One of the first things he did was run a model that his advisor, Claire Paris-Limouzy, developed that mapped where oil would have travelled after the spill, based on the specific conditions in the Gulf at the time. When he compared that map to the fishery closures, the results were intriguing: The model showed that oil likely traveled well beyond the bounds of the fishery closures.

When Berenshtein pored over past studies, the literature confirmed that oil had in fact been detected as far as the waters off the west coast of Florida, the Florida Keys, and Texas. That led to the question: Was the oil that spread beyond the fishery closures in high enough concentrations to be toxic to plant and animal life? And if so, what was the line between the toxic oil that satellites could detect, and the “invisible” but still toxic oil that they couldn’t?

One of the reasons for the discrepancy is the way that “toxicity” was being measured by fishery managers. “Until recently, the estimated satellite detection threshold was roughly equal to the estimated level of concern,” the paper’s authors write. But recent studies have found that organisms can be harmed at much lower concentrations due to a phenomenon called photo-induced toxicity.

After the spill, as oil floated around in the Gulf, it was exposed to ultraviolet radiation from the sun. When UV light interacts with the hydrocarbons in oil, it can produce new chemical compounds that can be more dangerous than the oil itself — especially to fish larvae and other young creatures. When the authors took this effect into account, they found that the oil concentration capable of killing many Gulf species is lower than what satellites can detect.

While satellite captures will remain essential for these kinds of calculations, according to Berenshtein, the study presents an additional framework that emergency managers can use to measure and account for the oil that’s “invisible” to satellites but still toxic to marine life. Accurate assessments of offshore drilling risk — and the effectiveness of emergency action after deadly spills — may benefit from the added precision this method can provide.

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  1. Hayek's Heelbiter


    Cost cutting/deregulation strikes again!

    According to industry sources, “automated valves” are a precautionary technology common in the North Sea, Asia-Pacific, India, West Africa, and Australia, but rigs in the Gulf of Mexico are notorious for the minimal adoption of preventative technology and companies using simple brass valves with manual levers run the risk of serious mishaps.

  2. Zagonostra

    Thinking back to the the Deep Horizon Oil Spill I remember waking up to the impotency of the Obama Presidency and the US government’s ability to deal with catastrophes in general.

    People at the time were making comparisons between Bush’s reaction to Katrina and Obama’s but criticism of the latter never seemed to stick.

    1. 1 Kings

      But Pres. Obama did the back stroke in an Alabama section of the Gulf.(a protected inlet not ‘corexited’) to show all the world everything is great?…
      While I thought aiding/abetting Geithner and Summers was the ‘tell that the gig was up, having the Pres of the US floating in a non toxic section of BP’s crime was the final of many nails in coffin.

      1. pretzelattack

        and afterward, obama pretended to drink a glass of water from the flint water supply, and then put on his comfortable shoes, his work done for the day.

    2. drumlin woodchuckles

      I don’t remember Obama being impotent. I remember Obama petulantly faking impotence when his active collusion with BP to coverup the size and extent of the problem was questioned in public. I remember Obama ( or his surrogates and henchcreeps) actively denying press any access to any part of the spill zone.

    3. Malcolm MacLeod, MD

      Having grown up in Tampa Bay, Fla. before and after WWll, I can tell you that by far the
      worst disaster to occur to that area was the cutting down of trees and dredging up of Gulf
      bottom to make more land to build cheap housing for retirees from the north. They literally
      wrecked the opening of Tampa Bay. Luckily, rising water will soon well cover all of that
      crappy junk. Gone is the beauty that was once there.

    1. JTMcPhee

      You can bet the settlement terms negotiated by the various government agencies and plaintiff actions preclude any new legal action. Looking at the Settlement Agreement and Consent Decree between the US and Gulf states and BP, there is a pretty broad release and covenant not to sue for any damages or penalties beyond those resolved by the Consent Decree.

    2. Susan the other

      There was enough dispute at the time over the use of the very toxic corexit that plenty of people understood that this would happen. Including BP. So if a court could prove intent to deceive it could work.

  3. The Rev Kev

    The University of Miami certainly did good work here but I do have an uneasy feeling. What I mean is that we’re going into the third decade of the 21st century and it is only now that such an important topic is being researched. After all, this is not the first oil spill by a long shot so why has this not been investigated before?

    For those interested, there are a whole series of articles – sixty three in total – about the Gull Oil Spill by Dahr Jamail. He is an America reporter that did independent work behind the lines during the Iraq war and afterwards on environmental issues. He is also the author of the book “The End of Ice”-

    1. Shiloh1

      Oh, I believe it. “Out of sight, out of mind”. Pay no mind to the conservation of matter. When the aggrieved parties show up unannounced in the c-suites and boardrooms then these environmental “whocoodanoed?” accidents will tail off considerably.

      Same goes for the “ship the airplane” hoodlums.

      Did Tony the CEO ever get his life back? He can have cocktails with Muilenburg.

  4. ambrit

    First, there is going to be a decades long ‘tail’ of cancers arising from this spill. Cancers in both humans and animals. Anecdotal data from visits to the Gulf Coast docks over the last decade has convinced me that the quality of the Gulf seafood harvests has never recovered from the initial shock.
    Second, this is but a “canary in the coal mine” event relative to the upcoming global sea rise pollution problems. All the toxic sites along the world’s littoral have to be capped or removed. This task alone will be staggering. The alternative will be decades, if not centuries, of dead and unusable inshore waters.
    Something like the “Andromeda Strain” would be a blessing in disguise.

    1. Susan the other

      Yes. The good ole IBGYBG attitude of modern industries who are polluting long into the future is staggering. And that’s not even the most frightening thing – the above post is telling us a terrifying thing: Our technology is both inadequate and misused. I’m thinking Fukushima here (as usual) – we never get any accurate info on the effects after the accident even though it’s a no-brainer it is still leaking into the ocean like a sieve. And just like any other poison it harms the young, the larvae, the eggs, the embryos far more than it harms the adults. We seem to have no technology for calculating these things. And no desire. And the effects probably are devastating on the micro biome as well. Oh, there wasn’t a mass die off of many species of birds and fish and animals all up and down the eastern Pacific because of radiation… it was just blablablah. Now we see this repeated with Deep Horizon, but worse. The technology to analyze the situation completely failed.

      1. ambrit

        I’d argue that it is the “profit centred” thinking of the corporations involved that lead, and still leads, to the disasters. At the time, thee were reports that the Deepwater Horizon rig was using substandard well logging materials and methods in order to meet a bonus deadline for the managers. One person of importance on the rig was reported to have been told to shut up and get with the program when he raised concerns about corner cutting.
        Fukushima is another example of this thinking gone awry. Dealing with the Chernobyl disaster is still a work in progress, thirty four years later. I remember seeing a Cousteau program about a wreck carrying almost a thousand barrels of tetraethyllead off the Italian port of Otranto, in the Adriatic. Even back then in 1977, the potential dangers of this single chemical were mentioned as being extreme. There are, as far as I can ascertain, no national or supranational organizations tasked with the clean-up and recovery of toxic spills and “mishaps.” At the least I would ecpect the UN to pick up that responsibility. Therein lies the rub. No one is enforcing responsibility for these ‘sins of omission and negligence.’
        Enforcement is the key. Perhaps we will have to take up that task ourselves.
        Crowdsourced ‘Instant Karma.’

        1. Calvin

          All corporate tax deductions should be eliminated until the equivalent amount of money is spent by the corporation to clean up any mess they make. No bankruptcy protection either, the money comes out of the pockets of all corporate directors involved at the time of the disaster.

  5. oaf

    …Studies show its not good to place too much scrutiny on corporations; don’t want to rock Mr. Market’s boat…

    ” Woe to thee who fault doth see; might just tank E-con-omy…


    1. ambrit

      Oafstradamus. Didn’t he write the (in)famous book of profitcies, “The Benjamins?” AKA “The Centuries: Notes.”

    1. Societal Illusions

      Except the party always ends and nobody is unaffected. Heard a good one today – “I’ll keep dancing while the party goes on, but I’ll be dancing near the doors.”

      What happens when the doors only lead back into the party?

      1. KiWeTO

        More likely those doors are locked to ensure no gatecrashing free riders and nobody leaves before paying their bill.

        In the game of last human standing, what good is it to be the last one alive of a society?

  6. John Farnham

    There seems to be an endless capacity for misanalysis and incorrect blame. The oil depletion allowance was dropped under Bush / Cheney. It made deepwater drilling more economically attractive – while it was still at the raw edge of technological feasibility. It was not a ‘spill’ but a blowout. Capping a fractured basin is always a questionable success reagrdless of Halliburton cementing shortcuts on the plug.. Leaking was reported years after. Corexit 9500 was applied by the Coast Guard. I recall an admiral had equity in it – yet it was known at the time to have dangerous side effects. It sank the crude – while making it more toxic and fluid, and sinking it. Out of sight, out of mind. Until you viewed residents’ complaints of health problems on YouTube.Things were crazy enough to make one think that – like NOLA / Katrina – government worked to make things much worse.

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