His team surveyed about 4, miles of coastline, and on their first assessment they found that about 1, miles of shoreline had been affected. This included about 80 miles of heavily oiled wetland.
Now, he says, 15 miles of heavily oiled beach remain, along with "some tens of miles" of moderately oiled coastline. This correlates with reports from a spokesman for the National Oceanic and Atmospheric Agency NOAA , who told the Guardian earlier this month that about 60 miles of coastline remain oiled. Not everyone agrees. Samantha Joye's research team from the University of Georgia believes that more oil is lurking beneath the surface of the water. They found a mile plume of oil and gas droplets in the depths of the Gulf of Mexico in May last year.
Their findings were recorded in a report published in the peer-reviewed journal Science. In December, Joye discovered a thick coating of oil, dead starfish and other organisms over an area of 2, square miles on the bottom of the ocean. Some independent scientists dispute Joye's claims. Simon Boxall , an expert in the Deepwater Horizon disaster from the National Oceanography Centre in Southampton, said that various organisations - "almost too many to mention" - have taken samples from the sea bed and have not found any evidence for Joye's claims.
He added: "She's talking about huge areas being affected, but she's basing it on one or two samples she's taken. BP's report placed most of the blame on Halliburton and Transocean , but its findings have been heavily criticised. Ed Markey, a senator investigating the spill in Congress, said at the time: "Of their own eight key findings, they only explicitly take responsibility for half of one.
BP is happy to slice up blame, as long as they get the smallest piece. Tony Hayward, who was BP's chief executive at the time of the explosion, said in a statement that the initial well integrity failure was down to a "bad cement job" by oil and gas equipment company Halliburton. Halliburton said that it had noticed "a number of substantial omissions and inaccuracies" in the BP report, and said that it was "confident that all the work it performed with respect to the Macondo well was completed in accordance with BP's specifications.
In its report on the disaster, BP blamed the rig owners, Transocean, for failing to adequately maintain the blowout preventer. The report said: "The BOP [blowout preventer] maintenance records were not accurately reported in the maintenance management system.
The condition of critical components in the yellow and blue pods and the use of a non-OEM [original equipment manufacturer] part, which were discovered after the pods were recovered, suggest the lack of a robust Transocean maintenance management system for Deepwater Horizon BOP.
Transocean responded with a vigorous rebuttal: "The BP report is a self-serving attempt to conceal the critical factor that set the stage for the Macondo incident: BP's fatally flawed well design. Amid these failures, the government increased oversight of the oil response and control efforts. The capping stack — essentially a smaller version of the blowout preventer and similarly designed to stop the flow of oil — would enable BP to shut the well, if successfully deployed.
Remotely operated vehicles installed the capping stack by July BP closed off the well on July 15, and for the first time in 87 days no oil flowed into the Gulf of Mexico.
It would take two more months before BP completed a relief well to divert oil to the surface, which it had begun drilling in early May, and permanently sealed the spewing reservoir.
Over the course of months following the blowout, it became painfully clear that BP had made no meaningful plans to deal with a potential spill.
BP may have legally paid for what its done, but morally and ethically it has not. On the morning of April 20, , workers aboard the Deepwater Horizon, a BP-operated deep sea drilling rig, were sealing an exploratory oil well 1, meters beneath the gulf. While they did so, a pocket of flammable gas travelling at nearly the speed of sound shot up the drill pipe, causing it to buckle.
An emergency valve, called a blowout preventer, designed to cap the well in the event of such a kick, failed. When the gas reached the rig, it triggered an explosion, killing 11 of the crew and sinking the rig. It would be 87 days before BP, which was operating the Deepwater Horizon, could bring the gusher under control. Several attempts to plug the well failed. A small air force took to the skies to coat the slick with chemicals meant to break it up and sink it to the sea floor.
Other pockets of oil were set ablaze in flames visible from outer space. By the time it was over, more than 2, kilometers of coast would be fouled in oil and marine life would be devastated. Thousands were put out of work in fisheries, tourism and energy. In the end, it would prove to be 12 times bigger than the Exxon Valdez spill in , the previous record holder. The Deepwater Horizon disaster signaled the risks of drilling for oil in one of the most culturally significant, ecologically diverse places in the world.
Take, for instance, the fish — which researchers at the University of South Florida say are still contaminated with hydrocarbons. Take the size of the spill itself, which a recent study has found to be far more extensive than initially thought, reaching as far as the southernmost tip of Florida.
Oil on Gulf waters after the Deepwater Horizon spill. Credit: Jonathan Henderson. Take, too, the continuing impact the spill had on human health. According to a government health study published seven years after the spill, tens of thousands of workers who first responded to the study are still wrestling with respiratory illnesses brought on by Corexit, the chemical used to disperse the spill.
And take that many of those who were affected by that chemical — mostly lower-income fisherman — are still ill, or have gone on to die. The more time that passes, the worse the spill seems to become, begging the question — could something like this happen again? As oil drilling moves farther offshore and deeper at sea, they say, the risk only increases.
Some 17 percent of the oil produced in the United States comes from the Gulf of Mexico. The remainder became trapped by a swirling eddy, which luckily contained the oil spill to one concentrated area. Winds and currents pushed the oil mass to the west where it eventually found its way into coastal Louisiana. As the majority of the oil made its way up toward the surface, some oil got left behind. Oil, dispersant, microbes, and mucus clumped together to form increased amounts of marine snow, dense particles which fall down to the seafloor from above.
It turns out that the oil and gas actually helped form marine snow and caused it to sink at a very high rate, in what researchers called a "dirty blizzard" event. This brought oil with it to the seafloor, and to the deep-sea communities that rely on nutrients in the form of certain chemical compounds like methane, often found in crude oil typically making its way to them from surface waters or bubbling up from hydrothermal vents below the seafloor.
There are several estimates of how much, and where, oil ended up on the seafloor—researchers generally agree between 3 and 10 percent of the oil released found its way to the bottom of the ocean.
Once the over million gallons of oil began spewing out of the damaged wellhead—where did it go? Keeping track of that much oil—especially as it sinks into the deep sea—is a difficult task that can't be done with eyes alone. Along with visual tracking, submersibles and computer models of the oil's movement helped researchers get a better sense of what path it took and where it ended up.
Like other autonomous underwater vehicles AUV , the robotic sub was programmed at the surface to navigate through the water on its own, collecting information on deep oil plumes from the Deepwater Horizon spill as it traveled.
Although satellites and aircraft helped show the extent of the spill at the surface, researchers hoped that the AUV would allow them to understand what was happening farther down in the water column.
The resulting data helped the researchers identify a persistent deep oil plume and link the oil in this plume to its source: the Deepwater Horizon blowout. To build models of oil movement at the surface, researchers first had to understand where ocean eddies, currents and waves carried the tiny oil particles.
This citizen science endeavor provided general information about how far the waves can carry a floating object and specific data points that can be used to improve models of where the oil disperses.
Their location gets tracked for weeks or months at a time and provide an unprecedented amount of location-based data for modeling. This information can be used to better predict oil movement in case of future spills, as well as predict other current-related movements like for marine debris and algal blooms.
After the Deepwater Horizon spill, oil was mixed throughout the ocean and made its way to coastal and deep-sea sediments. Researchers continue to collect samples from both the water and the sediment to determine if oil is present, and where exactly it came from.
Chemical analysis of oil found after a spill can be used to determine its original source. In the case of Deepwater Horizon, tracking the origins of oil slicks that appeared after the well was capped proved helpful in determining if a new leak might have sprung. At the outset, the twenty-person GoMRI Research Board adopted five main research themes to focus on: physical movement of the oil and dispersant, degradation of the oil and its interaction with the ecosystem, environmental effects of the oil and dispersant, development of technology for improved response and remediation, and the effects of oil and dispersant on human health.
GoMRI-funded studies have examined where the oil went after the spill and how the oil affected many types of marine life, including deep-sea coral ecosystems, seabirds, and jellyfish, to name just a few. As scientists in the Gulf collect organisms potentially affected by the oil, they will need to compare them to animals from previous decades to identify how they have changed, if at all.
Here's where Smithsonian Collections can play a role. Soon after the Deepwater Horizon oil spill, Smithsonian Collections staff plotted invertebrate holdings from the Gulf onto Google Earth. Since , invertebrate specimens have been deposited in the national collections of the National Museum of Natural History's Department of Invertebrate Zoology.
In the Gulf of Mexico, more than 57, invertebrates points on the map from 5, distinct collecting sites from 14 Mineral Management Service survey programs point colors have been cataloged. Following the Deepwater Horizon incident in late April , collections staff updated the files to reflect the latest areas affected by the spill in real-time.
A Smithsonian study of a oil spill on the coast of Panama attracted renewed interest for its insights into the effects of oil spills on coastal systems. The benchmark study PDF , published in , documented the damage oil causes to coastal and tidal habitats. It's particularly notable because it includes 15 years of ecological data about the area before the spill collected by the Smithsonian.
The affected area includes the Smithsonian biological reserve known as the Galeta Marine Laboratory. In this video interview with the Smithsonian Ocean Portal, he reflects on the Panama study and its implications for the Deepwater Horizon oil spill and reminds listeners that the greatest threats to the ocean— overfishing , climate change , and other types of pollution —combined actually exceed the devastation that unfolded in the Gulf of Mexico oil spill.
At Woods Hole Oceanographic Institution in Massachusetts, Chris Reddy studies the long-term effects of oil spills, as well as natural oil seeps that occur off the coast of Santa Barbara, California.
In this video , watch as he digs beneath the surface in Wild Harbor salt marsh in Cape Cod, Massachusetts to find layers of oil from a spill that occurred more than 40 years ago. This leftover oil continues to impact the wetland's ecology and wildlife. And to the naked eye, the marsh looks beautiful and pristine. Reddy testified before a Congressional panel investigating the Gulf oil spill.
In the immediate aftermath of the Deepwater Horizon oil spill, concerns about public health focused on people coming into direct contact with the oil and dispersants. A recent study discovered dispersants had an unintended benefit during the initial oil cleanup. As the dispersant broke apart the oil into smaller droplets it also decreased the amount of harmful gases that rose to the sea surface where emergency cleanup crews were working.
This decreased the health risks associated with working near the spill, reduced the number of days where it was too hazardous to work, and enabled a quicker cleanup.
However, long-term questions about oil spills and their impact on human health remain. The National Institutes of Health began to address these in a study that is tracking 33, cleanup workers and volunteers for a decade.
The research will assess whether exposure to crude oil and dispersants has an effect on physical and mental health. As the days, weeks, and months progressed the indirect impacts related to seafood consumption also gained attention. The chemicals in oil that are of most concern to humans are called polycyclic aromatic hydrocarbons PAHs.
Some of these are known to cause cancer.
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