Deepwater Horizon oil spill
|Deepwater Horizon oil spill|
|Location||Gulf of Mexico near Mississippi River Delta, United States|
|Date||Spill date: 20 April – 15 July 2010
Well officially sealed: 19 September 2010
|Operator||Transocean under contract for BP|
|Volume||4.9 million barrels (210,000,000 U.S. gallons; 780,000 cubic meters) ±10%|
|Area||2,500 to 68,000 sq mi (6,500 to 180,000 km2)|
|This article is part of a series about the
Deepwater Horizon oil spill
The Deepwater Horizon oil spill (also referred to as the BP oil spill, the BP oil disaster, the Gulf of Mexico oil spill, and the Macondo blowout) began on 20 April 2010 in the Gulf of Mexico on the BP-operated Macondo Prospect. It claimed eleven lives and is considered the largest accidental marine oil spill in the history of the petroleum industry, an estimated 8% to 31% larger in volume than the previously largest, the Ixtoc I oil spill. Following the explosion and sinking of the Deepwater Horizon oil rig, a sea-floor oil gusher flowed for 87 days, until it was capped on 15 July 2010. The total discharge has been estimated at 4.9 million barrels (210 million US gal; 780,000 m3).
A massive response ensued to protect beaches, wetlands and estuaries from the spreading oil utilizing skimmer ships, floating booms, controlled burns and 1.84 million US gallons (7,000 m3) of Corexit oil dispersant. After several failed efforts to contain the flow, the well was declared sealed on 19 September 2010. Some reports indicate the well site continues to leak. Due to the months-long spill, along with adverse effects from the response and cleanup activities, extensive damage to marine and wildlife habitats, fishing and tourism industries, and human health problems have continued through 2013. Three years after the spill, tar balls could still be found on the Mississippi coast. In July 2013, the discovery of a 40,000 pound tar mat near East Grand Terre, Louisiana prompted the closure of waters to commercial fishing.
Numerous investigations explored the causes of the explosion and record-setting spill. Notably, the U.S. government's September 2011 report pointed to defective cement on the well, faulting mostly BP, but also rig operator Transocean and contractor Halliburton. Earlier in 2011, a White House commission likewise blamed BP and its partners for a series of cost-cutting decisions and an insufficient safety system, but also concluded that the spill resulted from "systemic" root causes and "absent significant reform in both industry practices and government policies, might well recur".
In November 2012, BP and the United States Department of Justice settled federal criminal charges with BP pleading guilty to 11 counts of manslaughter, two misdemeanors, and a felony count of lying to Congress. BP also agreed to four years of government monitoring of its safety practices and ethics, and the Environmental Protection Agency announced that BP would be temporarily banned from new contracts with the US government. BP and the Department of Justice agreed to a record-setting $4.525 billion in fines and other payments but further legal proceedings not expected to conclude until 2014 are ongoing to determine payouts and fines under the Clean Water Act and the Natural Resources Damage Assessment. As of February 2013, criminal and civil settlements and payments to a trust fund had cost the company $42.2 billion.
|Frontline: The Spill (54:25), Frontline on PBS|
- 1 Background
- 2 Volume and extent of oil spill
- 3 Efforts to stem the flow of oil
- 4 Containment, collection and use of dispersants
- 5 Access restrictions
- 6 Consequences
- 7 Reactions
- 8 Legal aspects and settlements
- 9 See also
- 10 References
- 11 External links
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The Deepwater Horizon was a 9-year-old semi-submersible, mobile, floating, dynamically positioned drilling rig that could operate in waters up to 10,000 feet (3,000 m) deep. Built by South Korean company Hyundai Heavy Industries and owned by Transocean, the rig operated under the Marshallese flag of convenience, and was chartered to BP from March 2008 to September 2013. It was drilling a 35,050 feet (10,680 m) deep exploratory well in approximately 5,100 feet (1,600 m) of water. The well is situated in the Macondo Prospect in Mississippi Canyon Block 252 (MC252) of the Gulf of Mexico, in the United States' exclusive economic zone. The Macondo well is located roughly 41 miles (66 km) off the Louisiana coast. BP was the operator and principal developer of the Macondo Prospect with a 65% share, while 25% was owned by Anadarko Petroleum Corporation, and 10% by MOEX Offshore 2007, a unit of Mitsui.Cite error: The opening
<ref> tag is malformed or has a bad name (see the help page). At the time, 126 crew members were on board: seven BP employees, 79 of Transocean and employees of various other companies. Eleven workers were never found despite a three-day Coast Guard (USCG) search operation and are believed to have died in the explosion. Ninety-four crew were rescued by lifeboat or helicopter, 17 of whom were treated for injuries. The Deepwater Horizon sank on the morning of 22 April 2010 (coincidentally, Earth Day).
Volume and extent of oil spill
An oil leak was discovered on the afternoon of 22 April when a large oil slick began to spread at the former rig site. For 87 days the oil would flow without pause. While originally BP authorities gave their best estimate of a flow rate of 1,000 to 5,000 barrels per day (160 to 790 m3/d), according to the Flow Rate Technical Group, (FRTG) 62,000 barrels per day (9,900 m3/d) was a more realistic figure. The total estimated volume of leaked oil approximated 4.9 million barrels (210,000,000 US gal; 780,000 m3) with plus or minus 10% uncertainty., including oil that was collected. This makes it the largest accidental oil spill in history. BP challenges this figure, saying that the government overestimated the volume; email released in 2013 show that one BP employee's estimate matched those of the FRTG, but this was overruled by an external consultants. BP also argues that government figures do not reflect over 810,000 barrels (34 million US gal; 129,000 m3) of oil that was collected or burned before it could enter the Gulf waters.
According to the satellite images, the spill directly impacted 68,000 square miles (180,000 km2) of ocean which is comparable to the size of Oklahoma. By early June 2010, oil had washed up on 125 miles (201 km) of Louisiana's coast and along Mississippi, Florida, and Alabama barrier island coastlines. Oil sludge appeared in the Intracoastal Waterway and on Pensacola Beach and the Gulf Islands National Seashore. In late June, oil reached Gulf Park Estates, its first appearance in Mississippi. In July, tar balls reached Grand Isle and the shores of Lake Pontchartrain. In September a new wave of oil suddenly coated 16 miles (26 km) of Louisiana coastline and marshes west of the Mississippi River in Plaquemines Parish. In October, weathered oil reached Texas. As of July 2011, about 491 miles (790 km) of coastline in Louisiana, Mississippi, Alabama and Florida were contaminated by oil and a total of 1,074 miles (1,728 km) had been oiled since the spill began. As of December 2012, 339 miles (546 km) of coastline remain subject to evaluation and/or cleanup operations.
Concerns were raised about the appearance of underwater, horizontally-extended plumes of dissolved oil. Researchers concluded that deep plumes of dissolved oil and gas would likely remain confined to the northern Gulf of Mexico and that the peak impact on dissolved oxygen would be delayed and long lasting.
Two weeks after the wellhead was capped on 15 July 2010, the surface oil appeared to have dissipated, while an unknown amount of subsurface oil remained. Estimates of the residual ranged from a 2010 NOAA report that claimed about half of the oil remained below the surface to independent estimates of up to 75%. That means that over 100 million US gallons (2.4 Mbbl) remained in the Gulf. As of January 2011, tar balls, oil sheen trails, fouled wetlands marsh grass and coastal sands were still evident. Subsurface oil remained offshore and in fine silts. In April 2012, oil was still found along as much as 200 miles (320 km) of Louisiana coastline and tar balls continued to wash up on the barrier islands. In 2013, some scientists at the Gulf of Mexico Oil Spill and Ecosystem Science Conference said that as much as one-third of the oil may have mixed with deep ocean sediments, where it risks damage to ecosystems and commercial fisheries.
In 2013, more than 2.7 million pounds of "oiled material" were removed from the Louisiana coast. In the same year, tar balls were being reported almost every day on Alabama and Florida beaches.
Efforts to stem the flow of oil
First BP unsuccessfully attempted to close the blowout preventer valves on the wellhead with remotely operated underwater vehicles. Next it placed a 125-tonne (280,000 lb) containment dome over the largest leak and piped the oil to a storage vessel. While this technique had worked in shallower water, it failed here when gas combined with cold water to form methane hydrate crystals that blocked the opening at the top of the dome. Pumping heavy drilling fluids into the blowout preventer to restrict the flow of oil before sealing it permanently with cement ("top kill") also failed.
BP then inserted a riser insertion tube into the pipe and a stopper-like washer around the tube plugged the end of the riser and diverted the flow into the insertion tube. The collected gas was flared and oil stored on the board of drillship Discoverer Enterprise. Before the tube was removed, it collected 924,000 US gallons (22,000 bbl; 3,500 m3) of oil. On 3 June 2010, BP removed the damaged drilling riser from the top of the blowout preventer and covered the pipe by the cap which connected it to another riser. On 16 June a second containment system connected directly to the blowout preventer began carrying oil and gas to service vessels, where it was consumed in a clean-burning system. The United States government's estimates suggested the cap and other equipment were capturing less than half of the leaking oil. On 10 July the containment cap was removed to replace it with a better-fitting cap ("Top Hat Number 10"). Mud and cement were later pumped in through the top of the well to reduce the pressure inside it, completing the temporary measures.
Considerations of using explosives
In mid-May, United States Secretary of Energy Steven Chu assembled a team of nuclear physicists, including hydrogen bomb designer Richard Garwin and Sandia National Laboratories director Tom Hunter. Oil expert Matthew Simmons maintained that a nuclear explosion was the only way BP could permanently seal the well and cited successful Soviet attempts to seal off runaway gas wells with nuclear blasts. A spokesperson for the US Energy Department said that "neither Energy Secretary Steven Chu nor anyone else" ever considered this option. On 24 May BP ruled out conventional explosives, claiming that if blasts failed to clog the well, "we would have denied ourselves all other options."
Transocean's Development Driller III started drilling a first relief well on 2 May. GSF Development Driller II started drilling a second relief on 16 May. On 3 August, first test oil and then drilling mud was pumped at a slow rate of approximately 2 barrels (320 L) per minute into the well-head. Pumping continued for eight hours, at the end of which time the well was declared to be "in a static condition." On 4 August, BP began pumping cement from the top, sealing that part of the flow channel permanently.
On 3 September the 300-ton failed blowout preventer was removed from the well and a replacement blowout preventer was installed. On 16 September, the relief well reached its destination and pumping of cement to seal the well began. On 19 September, National Incident Commander Thad Allen declared the well "effectively dead" and said that it posed no further threat to the Gulf.
Recurrent or continued leakage
Oil slicks were reported in March and August 2011, in March and October 2012, and in January 2013. Repeated scientific analyses confirmed that the sheen was a chemical match for oil from Macondo well. The USCG initially said the oil was too dispersed to recover and posed no threat to the coastline, but later warned BP and Transocean that they might be held financially responsible for cleaning up the new oil. USGS director Marcia McNutt stated that the riser pipe could hold at most 1,000 barrels (160 m3) because it is open on both ends, making it unlikely to hold the amount of oil being observed.
In October 2012, BP reported that they had found and plugged leaking oil from the failed containment dome, now abandoned about 1,500 feet (460 m) from the main well. In December 2012, the USCG conducted a subsea survey; no oil coming from the wells or the wreckage was found and its source remains unknown. In addition, white, milky substance was observed seeping from the wreckage. According to BP and the USCG it is "not oil and it's not harmful."
Oceanographer Ian MacDonald said, "It's possible that the wreckage in 2010 somehow opened up a new fault on the seafloor." In May 2010, BP admitted they had "discovered things that were broken in the sub-surface" during the "top kill" effort.
Containment, collection and use of dispersants
The fundamental strategies for addressing the spill were containment, dispersal and removal. In summer 2010, approximately 47,000 people and 7,000 vessels were involved in the project. By 3 October 2012, federal response costs amounted to $850 million, mostly reimbursed by BP. As of January 2013, 935 personnel were still involved. By that time cleanup had cost BP over $14 billion.
It was estimated with plus or minus 10% uncertainty that 4.9 million barrels (780,000 m3) of oil was released from the well; 4.1 million barrels (650×103 m3) of oil went into the Gulf. The report led by the Department of the Interior and the NOAA said that of "75% [of oil] has been cleaned up by Man or Mother Nature", however only about 25% of released oil was collected or removed while about 75% of oil remained in the environment in one form or another. In 2012, Markus Huettel, a benthic ecologist at Florida State University, maintained that while much of BP's oil was degraded or evaporated, at least 60% remains unaccounted for.
Containment booms stretching over 4,200,000 feet (1,300 km) were deployed, either to corral the oil or as barriers to protect marshes, mangroves, shrimp/crab/oyster ranches or other ecologically sensitive areas. Booms extend 18–48 inches (0.46–1.2 m) above and below the water surface and were effective only in relatively calm and slow-moving waters. Including one-time use sorbent booms, a total of 13,300,000 feet (4,100 km) of booms were deployed. Booms were criticized for washing up on the shore with the oil, allowing oil to escape above or below the boom, and for ineffectiveness in more than three to four-foot waves.
The Louisiana barrier island plan was developed to construct barrier islands to protect the coast of Louisiana. The plan was criticised for its expense and poor results. Critics allege that the decision to pursue the project was political with little scientific input. The EPA expressed concern that the berms would threaten wildlife.
Use of Corexit dispersant
The spill was also notable for the volume of Corexit oil dispersant used and for application methods that were "purely experimental". Altogether, 1.84 million US gallons (7,000 m3) of dispersants were used; of this 771,000 US gallons (2,920 m3) were released at the wellhead. Subsea injection had never previously been tried but due to the spill's unprecedented nature BP together with USCG and EPA decided to use it. Over 400 sorties were flown to release the product. Although usage of dispersants was described as "the most effective and fast moving tool for minimizing shoreline impact", the approach continues to be investigated.
A 2011 analysis conducted by Earthjustice and Toxipedia showed that the dispersant could contain cancer-causing agents, hazardous toxins and endocrine-disrupting chemicals. Environmental scientists expressed concerns that the dispersants add to the toxicity of a spill, increasing the threat to sea turtles and bluefin tuna. The dangers are even greater when poured into the source of a spill, because they are picked up by the current and wash through the Gulf. According to BP and federal officials, dispersant use stopped after the cap was in place; however, marine toxicologist Riki Ott claimed that dispersant use continued after that date.
Corexit EC9500A and Corexit EC9527A were the principal variants. The two formulations are neither the least toxic, nor the most effective, among EPA's approved dispersants, but BP said it chose to use Corexit because it was available the week of the rig explosion. On 19 May, the EPA gave BP 24 hours to choose less toxic alternatives to Corexit from the National Contingency Plan Product Schedule, and begin applying them within 72 hours of EPA approval or provide a detailed reasoning why no approved products met the standards. On 20 May, BP determined that none of the alternative products met all three criteria of availability, non-toxicity and effectiveness. On 24 May, EPA Administrator Lisa P. Jackson ordered EPA to conduct its own evaluation of alternatives and ordered BP to reduce dispersant use by 75%. BP reduced Corexit use by 25,689 to 23,250 US gallons (97,240 to 88,000 l; 21,391 to 19,360 imp gal) per day, a 9% decline. On 2 August 2010, the EPA said dispersants did no more harm to the environment than the oil and that they stopped a large amount of oil from reaching the coast by breaking it down faster. However, some independent scientists and EPA's own experts continue to voice concerns about the approach.
Underwater injection of Corexit into the leak may have created the oil plumes which were discovered below the surface. Because the dispersants were applied at depth, much of the oil never rose to the surface. One plume was 22 miles (35 km) long, more than a mile wide and 650 feet (200 m) deep. In a major study on the plume, experts were most concerned about the slow pace at which the oil was breaking down in the cold, 40 °F (4 °C) water at depths of 3,000 feet (910 m).
The three basic approaches for removing the oil from the water were: combustion, offshore filtration, and collection for later processing. USCG said 33 million US gallons (120,000 m3) of tainted water was recovered, including 5 million US gallons (19,000 m3) of oil. BP said 826,800 barrels (131,450 m3) had been recovered or flared. It is calculated that about 5% of leaked oil was burned at the surface and 3% was skimmed. On the most demanding day 47,849 people were assigned on the response works.
From April to mid-July 2010 411 controlled in-situ fires remediated approximately 265,000 barrels (11,100,000 US gal; 42,100 m3). The fires released small amounts of toxins, including cancer-causing dioxins. According to EPA's report, the released amount is not enough to pose an added cancer risk to workers and coastal residents, while a second research team concluded that there was only a small added risk.
Oil was collected from water by using skimmers. In total 2,063 various skimmers were used. For offshore, more than 60 open-water skimmers were deployed, including 12 purpose-built vehicles. EPA regulations prohibited skimmers that left more than 15 parts per million (ppm) of oil in the water. Many large-scale skimmers exceeded the limit. Due to use of Corexit the oil was too dispersed to collect, according to a spokesperson for shipowner TMT. In mid-June 2010, BP ordered 32 machines that separate oil and water, with each machine capable of extracting up to 2,000 barrels per day (320 m3/d). After one week of testing, BP began to proceed and by 28 June, had removed 890,000 barrels (141,000 m3).
After the well was captured, the cleanup of shore became the main task of the response works. Two main types of affected coast were sandy beaches and marshes. On beaches the main techniques were sifting sand, removing tar balls, and digging out tar mats manually or by using mechanical devices. For marshes, techniques such as vacuum and pumping, low-pressure flush, vegetation cutting, and bioremediation were used.
Oil eating microbes
Dispersants are said to facilitate the digestion of the oil by microbes. Mixing dispersants with oil at the wellhead would keep some oil below the surface and in theory, allow microbes to digest the oil before it reached the surface. Various risks were identified and evaluated, in particular that an increase in microbial activity might reduce subsea oxygen levels, threatening fish and other animals.
Several studies suggest that microbes successfully consumed part of the oil. By mid-September, other research claimed that microbes mainly digested natural gas rather than oil. David L. Valentine, a professor of microbial geochemistry at UC Santa Barbara, said that the oil-gobbling properties of microbes had been grossly overstated.
Some experts suggested that the bacteria may have caused health issues for Gulf residents, such as an outbreak of skin rashes. Genetically modified Alcanivorax borkumensis was added to the waters to speed digestion. The delivery method of microbes to oil patches was proposed by the Russian Research and Development Institute of Ecology and the Sustainable Use of Natural Resources.
The first video images were released 12 May, and further video images were released by members of Congress who had been given access to them by BP.
During the spill response operations, at the request of the Coast Guard, the Federal Aviation Administration (FAA) implemented a 900-square-mile (2,300 km2) temporary flight restriction zone over the operations area. Restrictions were to prevent civilian air traffic from interfering with aircraft assisting the response effort. All flights in the operations' area were prohibited except flight authorized by air traffic control; routine flights supporting offshore oil operations; federal, state, local and military flight operations supporting spill response; and air ambulance and law enforcement operations. Exceptions for these restrictions were granted on a case-by-case basis dependent on safety issues, operational requirements, weather conditions, and traffic volume. No flights, except aircraft conducting aerial chemical dispersing operations, or for landing and takeoff, were allowed below 1,000 metres (3,300 ft). Notwithstanding restrictions, there were 800 to 1,000 flights per day during the operations.
Local and federal authorities citing BP's authority denied access to members of the press attempting to document the spill from the air, from boats, and on the ground, blocking access to areas that were open to the public. In some cases photographers were granted access only with BP officials escorting them on BP-contracted boats and aircraft. In one example, the U.S. Coast Guard stopped Jean-Michel Cousteau's boat and allowed it to proceed only after the Coast Guard was assured that no journalists were on board. In another example, a CBS News crew was denied access to the oil-covered beaches of the spill area. The CBS crew was told by the authorities: "this is BP's rules, not ours," when trying to film the area. Some members of Congress criticized the restrictions placed on access by journalists.
The FAA denied that BP employees or contractors made decisions on flights and access, saying those decision were made by the FAA and Coast Guard. The FAA acknowledged that media access was limited to hired planes or helicopters, but was arranged through the Coast Guard. The Coast Guard and BP denied having a policy of restricting journalists; they noted that members of the media had been embedded with the authorities and allowed to cover response efforts since the beginning of the effort, with more than 400 embeds aboard boats and aircraft to date. They also said that they wanted to provide access to the information while maintaining safety.
The greatest impact was on marine species. The spill area hosted 8,332 species, including more than 1,200 fish, 200 birds, 1,400 mollusks, 1,500 crustaceans, 4 sea turtles and 29 marine mammals. In addition to the 14 species under federal protection, the spill threatened 39 more ranging from "whale sharks to seagrass". Damage to the ocean floor especially endangered the Louisiana pancake batfish whose range is entirely contained within the spill-affected area. The oil contained approximately 40% methane by weight, compared to about 5% found in typical oil deposits. Methane can potentially suffocate marine life and create "dead zones" where oxygen is depleted. In March 2012, a definitive link was found between the death of a Gulf coral community and the spill. During a January 2013 flyover, former NASA physicist Bonny Schumaker noted a "dearth of marine life" in a radius 30 to 50 miles (48 to 80 km) around the well.
Between May and June 2010, the spill waters contained 40 times more Polycyclic aromatic hydrocarbons (PAH)'s than before the spill. PAHs are often linked to oil spills and include carcinogens and chemicals that pose various health risks to humans and marine life. The PAHs were most concentrated near the Louisiana Coast, but levels also jumped 2–3 fold in areas off Alabama, Mississippi and Florida. PAHs can harm marine species directly and microbes used to consume the oil would reduce marine oxygen levels. Estimates state that only 2% of the carcasses of killed mammals were recovered. In the first birthing season for dolphins after the spill, dead baby dolphins washed up along Mississippi and Alabama shorelines at about 10 times the normal number. Fifteen of the 406 dolphins that washed ashore in the first 14 months had oil on their bodies; the oil found on eight was linked to the spill. A NOAA/BP study in the summer of 2011 found that "many of the 32 dolphins studied were underweight, anemic and suffering from lung and liver disease, while nearly half had low levels of a hormone that helps the mammals deal with stress as well as regulating their metabolism and immune systems". Other conditions included drastically low weight and low blood sugar. By 2013, over 650 dolphins had been found stranded in the oil spill area, a four-fold increase over the historical average. NWF senior scientist Doug Inkley noted the death rates are unprecedented, and occurring high in the food chain, strongly suggest there is "something amiss with the Gulf ecosystem".
The oil and dispersant mixture, including PAHs, permeated the food chain through zooplankton. Signs of an oil-and-dispersant mix were found under the shells of tiny blue crab larvae. The use of dispersant made oil sink faster and more deeply into beaches, and possibly groundwater supplies. Corexit allowed the PAHs to permeate sand where, due to a lack of sunlight, degradation is slowed. Some types of spiders and other insects became far less numerous. Migratory birds carried chemicals from the spill as far as Minnesota. The vast majority of a small sample of Pelican eggs tested contained "petroleum compounds and Corexit".
In the summer of 2010, scientists reported immense underwater plumes of dissolved oil in addition to an 80-square-mile (210 km2) "kill zone" surrounding the blown well. Fish with oozing sores and lesions were first noted by fishermen in November 2010. Dispersant and PAHs from oil are believed to have caused "disturbing numbers" of mutated fish that scientists and commercial fishers began seeing in 2012, including 50% of shrimp found lacking eyes and eye sockets. Prior to the spill, approximately 1/10 of 1% of Gulf fish had lesions or sores. A report from the University of Florida said that many locations showed 20% of fish with lesions, while later estimates reach 50%. NOAA stated that dolphins and whales were dying at twice the normal rate in 2011. Scientists in 2012 reported finding "alarming numbers" of mutated crab, shrimp and fish resulting from chemicals released during the spill.
In 2012, tar balls continued to wash up along the Gulf coast. After Hurricane Isaac hit the Gulf in September 2012, about 565,000 pounds (256,000 kg) of oiled material traced to the spill was brought to land. Huge tar mats were uncovered during the storm, prompting beach closures. In 2013, researchers found that oil on the bottom of the seafloor does not seem to be degrading, and observed a phenomenon called "dirty blizzard": oil caused deep ocean sediments to clump together, falling to the ocean floor at ten times the normal rate in an "underwater rain of oily particles." The result could have long-term effects on both human and marine life because oil could remain in the food chain for generations. The same research suggested that as much as one-third of the oil remains in the Gulf.
Three years after the oil spill, the residual effects were still apparent, with tar balls still found on the Mississippi coast, as well as an oil sheen along a coastal marsh, and erosion on an island in Barataria Bay sped up by the death of mangrove trees and marsh grass.
In July 2013, the discovery of a 40,000 pound tar mat off the coast of East Grand Terre Island, Louisiana caused the state's Department of Wildlife and Fisheries to close the area to commercial fishing.
By June 2010, 143 spill-exposure cases had been reported to the Louisiana Department of Health and Hospitals; 108 of those involved workers in the clean-up efforts, while 35 were reported by residents. Chemicals from the oil and dispersant are believed to be the cause; it is believed that the addition of dispersants created an even more toxic substance (PAHs) when mixed with crude oil.
The United States Department of Health and Human Services set up the GuLF Study in June 2010 in response to these reports. The study is run by the National Institute of Environmental Health Sciences, and will last at least five years.
Mike Robicheux, a Louisiana physician, described the situation as "the biggest public health crisis from a chemical poisoning in the history of this country." In July, after testing the blood of BP cleanup workers and residents in Louisiana, Mississippi, Alabama, and Florida for volatile organic compounds, environmental scientist Wilma Subra said she was "finding amounts 5 to 10 times in excess of the 95th percentile"; she said that "the presence of these chemicals in the blood indicates exposure." Riki Ott, a marine toxicologist with experience of the Exxon Valdez oil spill, advised families to evacuate the Gulf. She said that workers from the Valdez spill had suffered long-term health consequences.
A 2012 survey of the health effects of the spill on cleanup workers reported "eye, nose and throat irritation; respiratory problems; blood in urine, vomit and rectal bleeding; seizures; nausea and violent vomiting episodes that last for hours; skin irritation, burning and lesions; short-term memory loss and confusion; liver and kidney damage; central nervous system effects and nervous system damage; hypertension; and miscarriages". Dr. James Diaz, writing for the American Journal of Disaster Medicine, said these ailments appearing in the Gulf reflected those reported after previous oil spills, like the Exxon Valdez. Diaz warned that "chronic adverse health effects, including cancers, liver and kidney disease, mental health disorders, birth defects and developmental disorders should be anticipated among sensitive populations and those most heavily exposed". Diaz also believes neurological disorders should be expected.
Two years after the spill, a study initiated by the National Institute for Occupational Safety and Health found biomarkers matching the oil from the spill in the bodies of cleanup workers. Other studies have reported a variety of mental health issues, skin problems, breathing issues, coughing, and headaches. In 2013, during the three-day "Gulf of Mexico Oil Spill & Ecosystem Science Conference", findings discussed included a '"significant percentage" of Gulf residents reporting mental health problems like anxiety, depression and PTSD. These studies also showed that the bodies of former spill cleanup workers carry biomarkers of "many chemicals contained in the oil".
A study that investigated the health effects among children in Louisiana and Florida living less than 10 miles from the coast found that more than a third of the parents reported physical or mental health symptoms among their children. The parents reported "unexplained symptoms among their children, including bleeding ears, nose bleeds, and the early start of menstruation among girls," according to David Abramson, director of Columbia University's National Center for Disaster Preparedness.
The spill had a strong economic impact to BP as also the Gulf Coast's economy sectors such as offshore drilling, fishing and tourism. On BP's expenditures on the spill included the cost of the spill response, containment, relief well drilling, grants to the Gulf states, claims paid, and federal costs, including fines and penalties. As of March 2012, BP estimated the company's total spill-related expenses do not exceed $37.2 billion. However, by some estimations penalties that BP may be required to pay have reached as high as $90 billion. In addition, in November 2012 the EPA announced that BP will be temporarily banned from seeking new contracts with the US government. Due to the loss of the market value, BP had dropped from the second to the fourth largest of the four major oil companies by 2013. During the crisis, BP gas stations in the United States reported sales off between 10 and 40% due to backlash against the company.
Local officials in Louisiana expressed concern that the offshore drilling moratorium imposed in response to the spill would further harm the economies of coastal communities as the oil industry employs about 58,000 Louisiana residents and has created another 260,000 oil-related jobs, accounting for about 17% of all Louisiana jobs. NOAA had closed 86,985 square miles (225,290 km2), or approximately 36% of Federal waters in the Gulf of Mexico, for commercial fishing causing $2.5 billion cost for the fishing industry. The U.S. Travel Association estimated that the economic impact of the oil spill on tourism across the Gulf Coast over a three-year period could exceed approximately $23 billion, in a region that supports over 400,000 travel industry jobs generating $34 billion in revenue annually.
Offshore drilling policies
On 30 April 2010 President Barack Obama ordered the federal government to hold the issuing of new offshore drilling leases and authorized investigation of 29 oil rigs in the Gulf in an effort to determine the cause of the disaster. Later a six-month offshore drilling (below 500 feet (150 m) of water) moratorium was enforced by the United States Department of the Interior. The moratorium suspended work on 33 rigs, and a group of affected companies formed the Back to Work Coalition. On 22 June, a United States federal judge on the United States District Court for the Eastern District of Louisiana Martin Leach-Cross Feldman when ruling in the case Hornbeck Offshore Services LLC v. Salazar, lifted the moratorium finding it too broad, arbitrary and not adequately justified. The ban was lifted in October 2010.
On 28 April 2010, the National Energy Board of Canada, which regulates offshore drilling in the Canadian Arctic and along the British Columbia Coast, issued a letter to oil companies asking them to explain their argument against safety rules which require same-season relief wells. On 3 May California Governor Arnold Schwarzenegger withdrew his support for a proposed plan to allow expanded offshore drilling projects in California. On 8 July, Florida Governor Charlie Crist called for a special session of the state legislature to draft an amendment to the state constitution banning offshore drilling in state waters, which the legislature rejected on 20 July.
On 30 April President Obama dispatched the Secretaries of the Department of Interior and Homeland Security, as well as the EPA Administrator and NOAA to the Gulf Coast to assess the disaster. In his 15 June speech Obama said, "This oil spill is the worst environmental disaster America has ever faced... Make no mistake: we will fight this spill with everything we've got for as long as it takes. We will make BP pay for the damage their company has caused. And we will do whatever's necessary to help the Gulf Coast and its people recover from this tragedy." Interior Secretary Ken Salazar stated, "Our job basically is to keep the boot on the neck of British Petroleum." Some observers suggested that the Obama administration was being overly aggressive in its criticisms, which some BP investors saw as an attempt to deflect criticism of his own handling of the crisis. Rand Paul accused President Obama of being anti-business and "un-American".
Public opinion polls in the U.S. were generally critical of the way the President Obama and the federal government handled the disaster and they were extremely critical of BPs response. Across the US, thousands participated in dozens of protests at BP gas stations and other locations, reducing sales at some stations by 10% to 40%.
Industry claimed that disasters are infrequent and that this spill was an isolated incident and rejected claims of a loss of industry credibility. The American Petroleum Institute (API) stated that the offshore drilling industry is important to job creation and economic growth. CEOs from the top five oil companies all agreed to work harder at improving safety. API announced the creation of an offshore safety institute, separate from API's lobbying operation.
The Organization for international investment, a Washington-based advocate for overseas investment in the United States, warned that the heated rhetoric was potentially damaging the reputation of British companies with operations in the United States and could spark a wave of U.S. protectionism that would restrict British firms from government contracts, political donations and lobbying.
In the UK, there was anger at the American press and news outlets for the misuse of the term "British Petroleum" for the company – a name which has not been used since British Petroleum merged with the American company Amoco in 1998 to form BP. It was said that the U.S. was 'dumping' the blame onto the British people and there were calls for British Prime Minister David Cameron to protect British interests in the United States. British pension fund managers (who have large holdings of BP shares and rely upon its dividends) accepted that while BP had to pay compensation for the spill and the environmental damage, they argued that the cost to the company's market value from President Obama's criticism was far outweighing the direct clean-up costs.
Initially BP downplayed the incident; its CEO Tony Hayward called the amount of oil and dispersant "relatively tiny" in comparison with the "very big ocean." Later, he drew an outpouring of criticism when he said that the spill was a disruption to Gulf Coast residents and himself adding, "You know, I'd like my life back." BP's chief operating officer Doug Suttles contradicted the underwater plume discussion noting, "It may be down to how you define what a plume is here… The oil that has been found is in very minute quantities." In June, BP launched a PR campaign and successfully bid for several search terms related to the spill on Google and other search engines so that the first sponsored search result linked directly to the company's website. On 26 July 2010, it was announced that CEO Tony Hayward was to quit and would be replaced by Bob Dudley, who is an American citizen and previously worked for Amoco.
Hayward's involvement in Deepwater Horizon has left him a highly controversial public figure. In May 2013 he was honored as a "distinguished leader" by the University of Birmingham, but his award ceremony was stopped on multiple occasions by jeers and walk-outs and the focus of a protest from People & Planet members.
In July 2013 his award of an honorary degree from Robert Gordon University was described as "a very serious error of judgement" by Friends of the Earth Scotland and "a sick joke" by the Student President.
The U.S. State Department listed 70 assistance offers from 23 countries, all being initially declined but later 8 had been accepted. The USCG actively requested skimming boats and equipment from several countries.
Legal aspects and settlements
In the United States the Deepwater Horizon investigation included several investigations and commissions, among others reports by National Incident Commander Thad Allen, USCG, National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling, Bureau of Ocean Energy Management, Regulation and Enforcement (BOEMRE), National Academy of Engineering, National Research Council, Government Accountability Office, National Oil Spill Commission, and Chemical Safety and Hazard Investigation Board. The Republic of the Marshall Islands Maritime Administrator conducted a separate investigation on the marine casualty. BP conducted its internal investigation.
An investigation of the possible causes of the explosion was launched on 22 April 2010 by the USCG and the Minerals Management Service. On 11 May the United States administration requested the National Academy of Engineering conduct an independent technical investigation. The National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling was established on 22 May to "consider the root causes of the disaster and offer options on safety and environmental precautions." The investigation by United States Attorney General Eric Holder was announced on 1 June 2010. Also the United States House Committee on Energy and Commerce conducted a number of hearings, including hearings of Tony Hayward and heads of Anadarko and Mitsui's exploration unit. According to the US Congressional investigation, the rig's blowout preventer, built by Cameron International Corporation, had a hydraulic leak and a failed battery, and therefore failed.
On 8 September 2010, BP released a 193-page report on its web site. The report places some of the blame for the accident on BP but also on Halliburton and Transocean. The report found that on 20 April 2010, managers misread pressure data and gave their approval for rig workers to replace drilling fluid in the well with seawater, which was not heavy enough to prevent gas that had been leaking into the well from firing up the pipe to the rig, causing the explosion. The conclusion was that BP was partly to blame, as was Transocean, which owned the rig. Responding to the report, Transocean and Halliburton placed all blame on BP.
On 9 November 2010, a report by the Oil Spill Commission said that there had been "a rush to completion" on the well and criticised poor management decisions. "There was not a culture of safety on that rig," the co-chair said.
The National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling released a final report on 5 January 2011. The panel found that BP, Halliburton, and Transocean had attempted to work more cheaply and thus helped to trigger the explosion and ensuing leakage. The report stated that "whether purposeful or not, many of the decisions that BP, Halliburton, and Transocean made that increased the risk of the Macondo blowout clearly saved those companies significant time (and money)." BP released a statement in response to this, saying, that "even prior to the conclusion of the commission's investigation, BP instituted significant changes designed to further strengthen safety and risk management." Transocean, however, blamed BP for making the decisions before the actual explosion occurred and government officials for permitting those decisions. Halliburton stated that it was acting only upon the orders of BP when it injected the cement into the wall of the well. It criticized BP for its failure to run a cement bond log test. In the report, BP was accused of nine faults. One was that it had not used a diagnostic tool to test the strength of the cement. Another was ignoring a pressure test that had failed. Still another was for not plugging the pipe with cement. The study did not, however, place the blame on any one of these events. Rather, it concluded that "notwithstanding these inherent risks, the accident of April 20 was avoidable" and that "it resulted from clear mistakes made in the first instance by BP, Halliburton and Transocean, and by government officials who, relying too much on industry's assertions of the safety of their operations, failed to create and apply a program of regulatory oversight that would have properly minimized the risk of deepwater drilling." The panel also noted that the government regulators did not have sufficient knowledge or authority to notice these cost-cutting decisions.
On 23 March 2011, BOEMRE (former MMS) and the USCG published the forensic examination report on blowout preventer, prepared by Det Norske Veritas. The report concluded that the primary cause of failure was that the blind shear rams failed to fully close and seal due to a portion of drill pipe buckling between the shearing blocks.
The US government report issued in September 2011 stated that BP is ultimately responsible for the spill, and that Halliburton and Transocean share some of the blame. The report states that the main cause was the defective cement job, and Halliburton, BP and Transocean were, in different ways, responsible for the accident. The report stated that, although the events leading to the sinking of Deepwater Horizon were set into motion by the failure to prevent a well blowout, the investigation revealed numerous systems deficiencies, and acts and omissions by Transocean and its Deepwater Horizon crew, that had an adverse impact on the ability to prevent or limit the magnitude of the disaster. The report also states that a central cause of the blowout was failure of a cement barrier allowing hydrocarbons to flow up the wellbore, through the riser and onto the rig, resulting in the blowout. The loss of life and the subsequent pollution of the Gulf of Mexico were the result of poor risk management, last‐minute changes to plans, failure to observe and respond to critical indicators, inadequate well control response, and insufficient emergency bridge response training by companies and individuals responsible for drilling at the Macondo well and for the operation of the drilling platform.
Spill response fund
On 16 June 2010, after BP executives met with President Obama, BP announced and established the Gulf Coast Claims Facility (GCCF), a $20 billion fund to settle claims arising from the Deepwater Horizon spill. This fund was set aside for natural resource damages, state and local response costs, and individual compensation, but could not be used for fines or penalties. Prior to establishing the GCCF, emergency compensation was paid by BP from an initial facility.
The GCCF was administrated by attorney Kenneth Feinberg. The facility began accepting claims on 23 August 2010. On 8 March 2012, after BP and a team of plaintiffs' attorneys agreed to a class-action settlement, a court-supervised administrator Patrick Juneau took over administration. Until this more than one million claims of 220,000 individual and business claimants were processed and more than $6.2 billion was paid out from the fund. 97% of payments were made to claimants in the Gulf States. In June 2012, the settlement of claims through the GCCF was replaced by the court supervised settlement program. During this transition period additional $404 million in claims were paid.
The GCCF and its administrator Feinberg had been criticized about the amount and speed of payments as well as a lack of transparency. An independent audit of the GCCF, announced by Attorney General Eric Holder, was approved by Senate on 21 October 2011. An auditor BDO Consulting found that 7,300 claimants were wrongly denied or underpaid. As a result about $64 million of additional payments was made. The Mississippi Center for Justice provided pro bono assistance to 10,000 people to help them "navigate the complex claims process." In a New York Times article, Stephen Teague, staff attorney at the Mississippi Center for Justice, argued that BP had become increasingly brazen in stonewalling payments. "But tens of thousands of gulf residents still haven't been fully compensated for their losses, and many are struggling to make ends meet. Many low-wage workers in the fishing and service industries, for example, have been seeking compensation for lost wages and jobs for three years."
In July 2013 BP made a motion in court to freeze payments on tens of thousands of claims, arguing inter alia that a staff attorney from the Deepwater Horizon Court-Supervised Settlement Program, the program responsible for evaluating compensation claims, had improperly profited from claims filed by a New Orleans law firm. The attorney is said to have received portions of settlement claims for clients he referred to the firm.(Teague 2013) The federal judge assigned to the case, Judge Barbier, refused to halt the settlement program, saying he had not seen evidence of widespread fraud, adding that he was "offended by what he saw as attempts to smear the lawyer administering the claims."
Civil litigation and settlements
By 26 May 2010, over 130 lawsuits relating to the spill had been filed against one or more of BP, Transocean, Cameron International Corporation, and Halliburton Energy Services, although it was considered likely by observers that these would be combined into one court as a multidistrict litigation. On 21 April 2011, BP issued $40bn worth of lawsuits against rig owner Transocean, cementer Halliburton and blowout preventer manufacturer Cameron. The oil firm alleged failed safety systems and irresponsible behaviour of contractors had led to the explosion, including claims that Halliburton failed to properly use modelling software to analyze safe drilling conditions. The firms deny the allegations.
On 2 March 2012, BP and plaintiffs agreed to settle their lawsuits. The deal would settle roughly 100,000 claims filled by individuals and businesses affected by the spill. On 13 August, BP asked US District Judge Carl Barbier to approve the settlement, saying its actions "did not constitute gross negligence or willful misconduct". On 13 January 2013, Judge Barbier approved a medical-benefits portion of BP's proposed $7.8 billion partial settlement. People living for at least 60 days along oil-impacted shores or involved in the clean-up who can document one or more specific health conditions caused by the oil or dispersants are eligible for benefits, as are those injured during clean-up. BP also agreed to spend $105 million over five years to set up a Gulf Coast health outreach program and pay for medical examinations. According to a group presenting the plaintiffs, the deal has no specific cap. BP says that it has $9.5 billion in assets set aside in a trust to pay the claims, and the settlement will not increase the $37.2 billion the company budgeted for spill-related expenses.
On 31 August 2012, the US Department of Justice (DOJ) filed papers in federal court in New Orleans blaming BP for the Gulf oil spill, describing the spill as an example of "gross negligence and willful misconduct." In their statement the DOJ said that some of BP's arguments were "plainly misleading" and that the court should ignore Bp's argument that the Gulf region is "undergoing a robust recovery". BP rejected the charges saying "BP believes it was not grossly negligent and looks forward to presenting evidence on this issue at trial in January." The DOJ also said Transocean, the owner and operator of the Deepwater Horizon rig, was guilty of gross negligence as well.
On 14 November 2012, BP and the US Department of Justice reached a settlement. BP will pay $4.5 billion in fines and other payments, the largest of its kind in US history. In addition, the U.S. government temporary banned BP from new federal contracts over its "lack of business integrity". The plea was accepted by Judge Sarah Vance of the United States District Court for the Eastern District of Louisiana on 31 January 2013. The settlement includes payments of $2.394 billion to the National Fish and Wildlife Foundation, $1.15 billion to the Oil Spill Liability Trust Fund, $350 million to the National Academy of Sciences for oil spill prevention and response research, $100 million to the North America Wetland Conservation Fund, $6 million to General Treasury and $525 million to the Securities and Exchange Commission.
On 3 January 2013 the US Justice Department announced "Transocean Deepwater Inc. has agreed to plead guilty to violating the Clean Water Act and to pay a total of $1.4 billion in civil and criminal fines and penalties". $800 million goes to Gulf Coast restoration Trust Fund, $300 million to the Oil Spill Liability Trust Fund, $150 million to the National Wild Turkey Federation and $150 million to the National Academy of Sciences. MOEX Offshore 2007 agreed to pay $45 million to the Oil Spill Liability Trust Fund, $25 million to five Gulf state and $20 million to supplemental environmental projects.
On 25 July 2013 Halliburton plead guilty to destruction of critical evidence after the oil spill and said it would pay the maximum allowable fine of $200,000 and will be subject to three years of probation.
Clean Water Act trial
BP and its partners in the oil well, Transocean and Halliburton, went on trial on 25 February 2013 in the United States District Court for the Eastern District of Louisiana in New Orleans to determine payouts and fines under the Clean Water Act and the Natural Resources Damage Assessment. The plaintiffs included the U.S. Justice Department, Gulf states and private individuals. Tens of billions of dollars in liability and fines are at stake. A finding of gross negligence would result in a four-fold increase in the fines BP would have to pay for violating the federal Clean Water Act, and leave the company liable for punitive damages for private claims.
The trial's first phase is to determine the liability of BP, Transocean, Halliburton, and other companies, and if they acted with gross negligence and willful misconduct. The second phase scheduled in September 2013 will focus on the flow rate of the oil and the third phase scheduled in 2014 will consider damages. According to the plaintiffs' lawyers the major cause of an explosion was the mishandling of a rig safety test, while inadequate training of the staff, poor maintenance of the equipment and substandard cement were also mentioned as things leading to the disaster. According to The Wall Street Journal the U.S. government and Gulf Coast states have prepared an offer to BP for a $16 billion settlement. However, it is not clear if this deal has been officially proposed to BP and if BP has accepted it.
In addition to the private lawsuits and civil governmental actions, the federal government charged numerous persons and entities involved with federal crimes.
The Justice Department filed the first criminal charge against Kurt Mix, a BP engineer in April 2012, for obstructing justice by deleting messages showing that BP knew the flow rate was three times higher than initial claims by the company, and knew that "Top Kill" was unlikely to succeed, but claimed otherwise. Three more BP employees were charged in November 2012: Donald Vidrine and Robert Kaluza, two site managers were charged with manslaughter for acting negligently in their supervision of key safety tests performed on the rig prior to the explosion and failure to alert onshore engineers of problems in the drilling operation, and David Rainey, BP's former vice-president for exploration in the Gulf of Mexico, was charged with obstructing Congress. Two employees are charged with obstruction of justice and for lying to federal investigators. Attorney General Eric Holder said that the criminal investigation is not yet over and that more company officials could be charged.
In the November 2012 resolution of the federal charges against it, BP also agreed to plead guilty to 11 felony counts related to the deaths of the 11 workers and paid a $4B fine.
The settlement resulting in the $1.4 billion Transocean fine also included Transocean's pleading guilty to a misdemeanor charge.
- List of industrial disasters
- List of oil spills
- Offshore oil and gas in the US Gulf of Mexico
- Timeline of the Deepwater Horizon oil spill
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||This article's use of external links may not follow Wikipedia's policies or guidelines. (December 2012)|
|Wikimedia Commons has media related to Deepwater Horizon oil spill.|
- Oil Spill Commission Final report to the President
- Deepwater BP Oil Spill at Whitehouse.gov
- Deepwater Horizon Incident, Gulf of Mexico from the National Oceanic and Atmospheric Administration (NOAA)
- Deepwater Horizon Joint Investigation by the U.S. Coast Guard and Mineral Management Service
- RestoreTheGulf.gov official U.S. Government Web site, taking over content and functions from Deepwater Horizon Response site
- BP Report on Accident, 8 September 2010, 14 Mb pdf download
- Bridge the Gulf Project Storytelling initiative led by Gulf Coast residents
- Smithsonian's Ocean Portal
- Science in a Time of Crisis: WHOI's response to the Deepwater Horizon Oil Spill a multimedia presentation from Woods Hole Oceanographic Institution
- Approaches for Ecosystem Services Valuation for the Gulf of Mexico After the Deepwater Horizon Oil Spill: Interim Report by the National Academy of Sciences
- Erik Stokstad (8 February 2013). "BP Research Dollars Yield Signs of Cautious Hope". Sciencemag.org. Retrieved 25 February 2013.
- CDC – Oil Spill Response Resources – NIOSH Workplace Safety and Health Topic
- Hertsgaard, Mark (22 April 2013). "What BP Doesn't Want You to Know About the 2010 Gulf Spill". Newsweek. The Daily Beast.
- The Role of BP in the Deepwater Horizon Explosion and Oil Spill: Hearing before the Subcommittee on Oversight and Investigations of the Committee on Energy and Commerce, House of Representatives, One Hundred Eleventh Congress, Second Session, June 17, 2010
Lead state agency websites
- Florida Department of Environmental Protection (DEP)
- Mississippi DEQ
- State of Florida Oil Spill Academic Task Force
- Full coverage on C-SPAN video library
- Full coverage on Democracy Now
- Full coverage on Al Jazeera English
- Full coverage on CNN
- Full coverage on The Guardian
- Full coverage from the Los Angeles Times
- Full coverage from The Miami Herald
- Full coverage from The New York Times
- Full coverage from The Times-Picayune (New Orleans)
- Full coverage from the Press-Register (Mobile, Alabama)
- Full coverage from The Wall Street Journal
- Full coverage collected news and commentary at The Washington Post
- Full coverage from GRITtv
- Full coverage from The News-Press (Ft. Myers, FL)
- Mapping the Response to BP Oil Spill in the Gulf of Mexico (GeoPlatform.gov)
- Gulf Oil Spill Tracker interactive map and form for citizen reporting (SkyTruth.org)
- Map and Estimates of the Oil Spilled (The New York Times)
- Where Oil Has Made Landfall (The New York Times)
- Gulf Oil Spill 2010 Projected Trajectory from Louisiana Earth
- Rig fire at Deepwater Horizon 4/21/10, video at CNN iReport
- GOES-13 satellite images on the CIMSS Satellite Blog
Animations and graphics
- BBC News – interactive animation to the disaster and blocking efforts
- New York Times exploded view diagrams on the methods used to stop the oil spill
- Graphic: Where the oil and gas went