Notice of Intent to begin restoration scoping and prepare a Programmatic Environmental Impact Statement. After four years shoreline assessments are completed. Up to 18 SCAT teams operating simultaneously conducted ground surveys of over 4, miles of shoreline over 28, miles with repeat surveys. In the Clean Water Act Trial, Judge Barbier determined that 4 million barrels of crude oil were released from the reservoir, of which 3.
BP, the United States, and the five Gulf states agreed to a settlement, or Consent Decree, resolving claims for federal civil penalties and natural resource damages related to the Deepwater Horizon spill. April 20, Wellhead blowout. Image credit: U. Coast Guard. April 21, NOAA notified. April 21, Preassessment begins. April 22, Drilling rig sinks. April 22, Aerial dispersant operations begin. April 28, First controlled burn of floating oil.
April 28, First fishery closures in state waters. Teams start systematic aerial and ground surveys of affected shorelines. May 2, Relief well. May 6, Containment domes. May 15, Oil siphoning. May 22, National Commission announced. May 26, Top kill and junk shot. Image credit: BP. May 30, Moratorium on Gulf drilling.
In the distance, she could see smoke billowing into the sky. There seemed to be more ships on the water than usual, too. With limited internet access on the ship, she asked Joye to figure out what was going on. According to reports that night, 11 workers on the platform were missing; officials later confirmed that the workers had all died in the explosion.
As she read the initial descriptions of the explosion, Joye felt her stomach tightening into a knot. If the undersea safety measures designed to prevent a blowout had failed, it would be difficult to fix any leaks. The oil rig sunk the next day.
For the 87 days that followed, the wellhead, damaged by the explosion, spewed petroleum deep below the surface of the Gulf of Mexico. In the end, between 4 million and 5 million barrels of petroleum leaked into the Gulf, making the spill the largest single accidental release of gas and oil into the ocean in history. Cement pumped in through this secondary well permanently sealed the petroleum reservoir.
In the years since the blowout, scientists have studied many aspects of the spill. Five days after that announcement, Bobby Jindal, then governor of Louisiana, declared a state of emergency. Most previous spills had been single events—for example, the grounding of an oil tanker and the rapid release of the petroleum on board. The Deepwater Horizon accident had left the wellhead gushing oil constantly, and because the rupture was about 1.
As the oil began to reach the surface, responders turned to a familiar line of defense in oil-spill cleanup: dispersants. These proprietary solutions contain many compounds, including surfactants, emulsifying agents, and solvents. Once sprayed on an oil slick, the dispersants act like a detergent and break the oil into smaller droplets that can then mix into the water, where oil-eating microbes can degrade it.
Using dispersants offshore can reduce the amount of oil that washes onto the beaches, protecting both people and fragile coastal ecosystems, Overton says. But the use of the chemicals has been controversial since they were first deployed in large quantities in the Torrey Canyon spill off the southwest coast of Great Britain. The dispersants wreaked massive environmental damage, decimating marine organisms including seaweed, plankton, and mollusks.
Later analysis revealed that ecosystems in areas treated with the chemicals recovered up to five times as slowly as those that were not. And although the formulations of dispersants have changed significantly in the decades since that spill, many people are still wary of their use.
There, the oil could eventually be metabolized by microbes, settle to the ocean floor, or get carried out of the Gulf entirely. This approach might also help improve the air quality for response workers on the surface by trapping in the depths some compounds that would have volatilized.
But all existing tests on the efficacy of dispersants had been conducted on the surface of water, says Elizabeth Kujawinski, a chemical oceanographer at Woods Hole Oceanographic Institution. There was no guarantee that they would perform the same way in the crushing depths of the ocean. Related: Reckoning With Oil Spills. Despite these safety and efficacy concerns, the US Environmental Protection Agency authorized the first-ever subsurface use of dispersants on May 15, Eventually, engineers pumped almost 3 million L of two Corexit formulations below the surface of the Gulf.
Aircraft and boats sprayed another 3. Of that amount, about half made it up to the surface Proc. Many of the light hydrocarbons, which are highly soluble in seawater, dissolved in the water column. And much of the rest of what was released formed deep plumes of oil that eventually stretched more than 32 km from the gushing well—an indication, perhaps, that injecting the dispersants at depth had prevented some oil from reaching the surface.
But the presence of the deep-sea plume did not convince some researchers that the dispersants had done their job. The size and shape of the hole in the well, as well as the large amounts of natural gas in the fluid inside the Macondo reservoir, may just as easily have caused the oil to atomize and form a plume, says Claire Paris-Limouzy, a biological oceanographer at the University of Miami.
That was more catastrophic than not using anything. The dispersants also affected the crews that helped clean up the spill. According to surveys of spill-cleanup workers, many who had been exposed to dispersants showed symptoms related to the chemicals, such as skin irritation and respiratory problems, several years after the spill. More than half the exposed workers experienced skin irritation; about a quarter reported a cough or burning eyes or both Environ.
Health Perspect. A whistleblower report published by the Government Accountability Project in April documents ongoing health problems in response workers. In her studies using the model organism Caenorhabditis elegans , Pan has found that both crude oil from the Macondo reservoir and Corexit A inhibit reproductive function, especially when exposure occurs during development.
And a mixture of crude oil and dispersant is much more toxic to C. Another study that looked at toxicity to a key plankton species found that the dispersant-oil mixtures were more than 50 times as toxic as oil alone Environ. Where the response went wrong, he says, is in not collecting crucial data, such as air-quality measurements, that could have informed whether the solutions were working as hoped.
Researchers have known that a variety of so-called weathering processes, both natural and human driven, transform and degrade the hydrocarbons in oil over varying timescales on the surface of a body of water. The most volatile components, such as low-molecular-weight alkanes, evaporate off almost immediately.
Oil that is dispersed—either naturally or chemically—is mixed into the water column, where hydrocarbon-degrading microorganisms metabolize it. Some oil sitting on the surface mixes with seawater to form viscous, sticky emulsions.
And some fraction of the oil is transformed into partially oxidized compounds by photochemical processes. And these reactions were thought to occur in the weeks or months after a spill, after much of the oil had already been cleaned up by other means. Contact us to opt out anytime. Furthermore, the researchers showed that these reactions likely occurred in the hours and days after the oil reached the surface, with two-thirds of the oxidation occurring within the first 10 days of exposure Environ.
As the oil eventually receded, many who fought to clean it up became seriously ill. Many of them have died of respiratory complications, including cancer.
In the days following the blowout, some 47, people, mostly newly jobless fisherman, were contracted by BP to pilot their boats into the slick pulling skimmers. Others worked in Mississippi, Alabama and Florida to siphon oil off the beaches. Almost immediately, thousands of them broke out in rashes. They began to cough up blood and developed wheezes. Some were plagued with migraines. Many complained of burning eyes and memory loss.
Still others were struggled with new heart aliments, kidney problems, liver damage, and discharge from their ears. Some experienced cognitive decline and anxiety attacks. What all of them had in common is their exposure to Corexit, an oil dispersant that contains an array of toxic chemicals, but which BP assured the workers was as safe to use as dishwashing liquid. From the first days of the spill through the eventual capping of the well that following July, BP oversaw the dumping of 7 million liters of the dispersant from airplanes flown over the Gulf.
Ten years later, controversy still rages about the wisdom of carpet-bombing the Gulf with these chemicals, and documents released since reveal that government scientists expressed concern at the time about the health consequences of mixing such large quantities of dispersants with the millions of barrels of sweet crude. Oil and dispersants are a toxic stew. When the two are combined, they unleash heavy metals and hydrocarbons like benzene, hexane, and toluene, which are known carcinogens.
Dispersants like Corexit contain solvents meant to break oil down into tiny droplets that sink. But when ocean water evaporates, so do these chemicals. When they are carried inland by the wind, they can sicken those who inhale them. In their interviews, many of these patients who worked on spill cleanup said they were discouraged by BP contractors from using protective gear, even though, as study later showed , Corexit, when mixed with oil is 52 times more toxic than oil alone.
Those who complained were met with efforts to silence them. In their affidavits and interviews, former cleanup workers attested to being the victims of an intimidation campaign for revealing they were ill.
The sick were followed, their homes broken into, their trash ransacked, their privacy corroded. They became increasingly isolated. Their advocates, meanwhile, were attacked in vicious online campaigns. With the rise of social media, Internet trolls connected to BP swarmed whistleblowers who posted photos of oiled beaches.
He began coughing up blood and suffering blinding migraines during the first month the blowout continued. He still suffers from chronic bronchitis and wears special sunglasses to correct a heightened light sensitivity he has experienced since the disaster. Burning and skimming operations in the Gulf of Mexico; June 10, When Moore sought help at an Alabama hospital, he was told he was making things up for a quick payday. Like hundreds of others, he eventually found treatment far away from the Gulf.
It established what Moore and others had known for years — cleanup workers exposed to Corexit during the nearly three months oil spilled into the sea were likely to experience coughs, wheezing, chest tightness and eye, nose, throat and lung irritation.
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