In pursuit of oil, a man goes into the tundra, climbs mountains and conquers sea bottom. But oil does not always give up without a fight, and as soon as a person loses his vigilance, “black gold” turns into a real black death for all living things. This happened quite recently in the Gulf of Mexico, where the ultra-modern oil platform DeepWater Horizon dealt a crushing blow to nature and human pride.
An object: oil platform DeepWater Horizon, 80 km off the coast of Louisiana (USA), Gulf of Mexico.
An ultra-deepwater oil drilling platform has been leased by BP to develop the promising Macondo field. The length of the platform reached 112 m, width - 78 m, height - 97.4 m, it went 23 meters under water and had a mass of over 32 thousand tons.
Victims: 13 people, 11 of them died during the fire, another 2 died during the liquidation of the consequences. 17 people were injured varying degrees gravity.
Source: US Coast Guard
Causes disasters
U major disasters there is no single reason, which was confirmed by the explosion oil platform DeepWater Horizon. This accident was the result of a whole chain of violations and technical malfunctions. Experts say it was only a matter of time before a platform disaster occurred.
It is interesting that several parallel investigations into the causes of the disaster were carried out, which led to different conclusions. Thus, the report made by BP indicates only 6 main causes of the accident, and main reason accident named human factor. A more authoritative report made by the Bureau of Ocean Energy Resources Management, Regulation and Enforcement (BOEMRE) and the US Coast Guard already names 35 main reasons, and 21 of them are blamed entirely on BP.
So who is to blame for the DeepWater Horizon explosion and subsequent environmental disaster? The answer is simple - BP, which was chasing profit, and in this pursuit neglected basic safety rules and deep-sea drilling technologies. In particular, the well cementing technology was violated, and the specialists who arrived to analyze the cement were simply kicked out of the drilling site. Were also disabled important systems control and security, so no one knew what was really going on under the ocean floor.
The result was an explosion and fire on the platform, a colossal oil spill and the title of one of the largest environmental disasters in the entire history of civilization.
Chronicle of events
Problems on the platform began almost from the first day of its installation, that is, from the beginning of February 2010. The well was drilled in a hurry, and the reason is simple and banal: the DeepWater Horizon platform was leased by BP, and every day it cost half a million (!) dollars!
However, the real problems began in the early morning of April 20, 2010. The well was drilled, a depth of just over 3,600 meters below the bottom was reached (the depth of the ocean in this place reaches one and a half kilometers), and it remained to complete the work of strengthening the well with cement in order to reliably “lock in” the oil and gas.
This process in a simplified form goes like this. Special cement is fed into the well through the casing, then drilling fluid, which, with its pressure, displaces the cement and forces it to rise up the well. The cement hardens quickly enough and creates a reliable “plug”. And then sea water is pumped into the well, which washes out the drilling fluid and any debris. A large protective device is installed on top of the well - a preventer, which in the event of an oil and gas leak simply blocks their access to the top.
Since the morning of April 20, cement has been pumped into the well, and by lunchtime the first tests to test the reliability of the cement “plug” have already been carried out. Two specialists flew to the platform to check the quality of cementing. This inspection was supposed to last about 12 hours, but the management, who could not wait any longer, decided to abandon the standard procedure, and at 14.30 the specialists with their equipment left the platform, and soon they began to pump drilling fluid into the well.
Suddenly, at 18.45, the pressure in the drill string increased sharply, reaching 100 atmospheres in a few minutes. This meant that gas was leaking from the well. However, at 19.55 water pumping began, which simply could not be done. Over the next hour and a half, water was pumped from with varying success, since sudden pressure surges forced work to be interrupted.
Finally, at 21.47 the well does not hold up, gas rushes up the drill string, and 21.49 There was a monstrous explosion. After 36 hours, the platform tilted heavily and sank safely to the bottom.
The oil slick has reached the coast of Louisiana. Source: Greenpeace
Consequences of the explosion
An accident on an oil platform has grown into an environmental disaster, the scale of which is simply amazing.
main reason environmental disaster- oil spill. Oil from the damaged well (as well as accompanying gases) continuously flowed for 152 days (until September 19, 2010), and during this time ocean waters received more than 5 million barrels of oil. This oil caused irreparable damage to the ocean and many coastal areas of the Gulf of Mexico.
In total, almost 1,800 kilometers of coastlines were polluted with oil, white sandy beaches turned into black oil fields, and an oil slick on the surface of the ocean was visible even from space. Oil has caused the death of tens of thousands of marine animals and birds.
Dealing with the consequences oil pollution was carried out by tens of thousands of people. “Black gold” was collected from the surface of the ocean by special vessels (skimmers), and the beaches were cleaned only by hand - modern science cannot offer mechanized means to solve this problem, it is so complex.
The main consequences of the oil spill were eliminated only by November 2011.
The accident had not only environmental, but also colossal (and most negative) consequences. economic consequences. Thus, the BP company lost about 22 billion dollars (this includes losses from the loss of a well, payments to victims, and costs to eliminate the consequences of the disaster). But they suffered even more significant losses coastal areas Gulf of Mexico. This is due to the collapse of the tourism sector (who will go on vacation to dirty oil beaches?), the ban on fishing and other activities, etc. As a result of the oil spill, tens of thousands of people who had nothing to do with this oil were left without work.
However, the disaster had completely unexpected consequences. For example, while studying an oil spill, bacteria unknown to science were discovered that feed on oil products! It is now believed that these microorganisms significantly reduced the consequences of the disaster, as they absorbed huge amounts of methane and other gases. It is possible that using these bacteria, scientists will be able to create microorganisms that in the future will help deal with oil spills quickly and cheaply.
Workers clean up the consequences of an oil spill. Port Fourchon, Louisiana. Photo: Greenpeace
Current situation
Currently, no work is being carried out at the site where the DeepWater Horizon platform died. However, the Macondo field, which was developed by BP with the help of a platform, stores too much oil and gas (about 7 million tons), and therefore new platforms will definitely come here in the future. True, the same people will be drilling the bottom - BP employees.
No comments. Photo: Greenpeace
On April 20, 2010, one of the most serious environmental tragedies in history occurred in the Gulf of Mexico. of this region. As a result of an explosion on a BP oil platform, 11 people were killed and 17 others were reported injured.
The consequences of the accident still have a devastating impact on the animal world. Following the disaster, which released approximately 5,000,000 barrels of oil into the waters, there was a dramatic increase in mortality among 14 species of animals common to the Bay Area. The oil has not disappeared anywhere, it is at the bottom of the bay, it is washed ashore and carried by water into the swamp. An estimated 900 dolphins have been found dead or stranded since April 2010. This number significantly exceeds what was previously recorded for the same period of life expectancy.
Dolphins that live in areas of the Gulf contaminated with oil suffer from numerous liver and lung diseases, are lethargic and have low body weight. The fact that dolphins, at the top of food chains, have so many health problems indicates the deep damage done to the environment. Since the accident, about 500 turtles have been found dead in the Gulf of Mexico each year, a significant increase over normal levels.
In addition, scientists have discovered an increased content toxic substances in the blood of birds that spend the winter on the coast near the bay, and in the blood of sperm whales, which often swim to the place where the accident occurred, an abnormally high content of chromium and nickel was recorded - metals that have a destructive effect on cells.
The cause of the oil spill on the platform where the British oil company British Petroleum was drilling at the Macondo well was an explosion, which killed 11 people. The leak was stopped only after 5 months. During this time, about 760,000,000 liters of oil entered the water. This created one of the largest stains in US history. The spill threatens hundreds of kilometers coastline, and it all started with an explosion on the platform.
Nearly thousands of ships battled to contain the oil slick fueled by an exposed well. Crude oil came from the ocean floor. No one could have predicted the events that took place.
There were more than a hundred people on the tower and people were jumping overboard. It was necessary to act immediately. The incident occurred 213 kilometers from the base coast guard and 190 kilometers from the Coast Guard helicopter rescue base. Rescuers flying to help saw the glow of fire 145 km from the site, which once again confirmed the seriousness of the situation.
When the platform Deepwater Horizon sank at a depth of 1.5 km, there were no signs that oil was coming from the well and its vertical pipe. It appears that the leak has somehow stopped. As the fire destroyed oil on the surface of the sea, rescuers worried that the tragedy was not over yet. The well is not plugged.
The seriousness of the tragedy reaches its peak - oil begins to appear from the depths of the bay and this quickly aggravates the matter. A slick forms that becomes the largest pollution spill ever in the Gulf of Mexico.
The oil giant's PR people claim that the consequences of the accident have been virtually eliminated, but sailors working in the Gulf may argue with this. Their current catch is eyeless shrimp and mutant fish. Nothing like this had ever been seen before.
Shrimp without eyes, fish with severe injuries, crabs with previously unseen spots - are no longer decoy. Fishermen catch hundreds of kilograms of mutants and sick inhabitants of the bay. Overnight catches of 400 pounds of shrimp may contain 100 or even 200 pounds of eyeless shrimp.
Scientists are even afraid to imagine what other surprises the disaster of four years ago will bring them. But they firmly believe that it will take at least 10 years to completely clean up the Gulf of Mexico. However, BP has a slightly different point of view. The oil company responsible for the accident is spending millions of dollars on commercials. Their goal is to show that the bay is clean and the seafood is safe. Video footage from environmentalists and testimony from local residents suggests otherwise.
On April 22, 2010, an accident occurred at the drilling rig Deepwater platform Horizon, which BP used to produce oil in the Gulf of Mexico. As a result of the disaster, 11 people died and hundreds of thousands of tons of oil spilled into the sea. Due to the huge losses incurred as a result of the incident, BP was forced to sell assets around the world.
About 5 million barrels of crude oil spilled into the Gulf of Mexico.
Extinguishing a platform in the Gulf of Mexico. April 2010 Photo: Commons.wikimedia.org
The Deepwater Horizon ultra-deep drilling platform was built by the shipbuilding company Hundai Industries (South Korea) by order of R & B Falcon (Transocean Ltd.). This platform was launched in 2001, and some time later it was leased to the British oil and gas company British Petroleum (BP). The lease period has been extended several times, last time- until the beginning of 2013.
In February 2010, BP began developing the Macondo field in the Gulf of Mexico. A well was drilled at a depth of 1500 meters.
Oil platform explosion
April 20, 2010, 80 km from the coast American state Louisiana on the Deepwater Horizon oil platform there was a fire and explosion. The fire lasted more than 35 hours; firefighting vessels that arrived at the scene of the accident tried unsuccessfully to extinguish it. On April 22, the platform sank in the waters of the Gulf of Mexico.
As a result of the accident, 11 people went missing; searches for them were carried out until April 24, 2010 and did not yield any results. 115 people were evacuated from the platform, including 17 injured. Subsequently, world news agencies reported that two more people died during the liquidation of the consequences of the accident.
Oil spill
From April 20 to September 19, liquidation of the consequences of the accident continued. Meanwhile, according to some experts, about 5,000 barrels of oil entered the water every day. According to other sources, up to 100,000 barrels per day entered the water, as stated by the US Secretary of the Interior in May 2010.
By the end of April, the oil slick reached the mouth of the Mississippi River, and in July 2010, oil was discovered on the beaches of the US state of Texas. In addition, the underwater oil plume stretched 35 km in length at a depth of more than 1,000 meters.
Over 152 days, about 5 million barrels of oil spilled into the waters of the Gulf of Mexico through damaged well pipes. The area of the oil spill was 75 thousand km².
Photo: www.globallookpress.com
Elimination of consequences
After the Deepwater Horizon sank, efforts were made to seal the well, and later oil spill cleanup efforts began to contain the spread of the oil slick.
Almost immediately after the accident, specialists put plugs on the damaged pipe and began work on installing a steel dome, which was supposed to cover the damaged platform and prevent an oil spill. The first installation attempt was unsuccessful, and on May 13 it was decided to install a smaller dome. The oil leak was completely eliminated only on August 4, thanks to the fact that... To completely seal the well, two additional relief wells had to be drilled, into which cement was also pumped. Full sealing was announced on September 19, 2010.
To eliminate the consequences, tugs, barges, rescue boats, and BP submarines were raised. They were helped by ships, planes and naval equipment US Navy and Air Force. More than 1,000 people took part in the liquidation of the consequences, about 6,000 military personnel were involved National Guard USA. To limit the area of the oil slick, dispersants (active substances used to settle oil slicks) were sprayed. Booms were also installed to contain the spill area. Mechanical oil collection was used, both with the help of special vessels and manually - by volunteers on the US coast. In addition, experts decided to resort to controlled burning of oil spills.
Photo: www.globallookpress.com
Incident investigation
According to an internal investigation conducted by BP safety officials, the accident was blamed on worker errors, technical failures and design flaws in the oil platform itself. The prepared report stated that rig personnel misinterpreted pressure measurements during a well leak test, causing a stream of hydrocarbons rising from the bottom of the well to fill the drilling platform through a vent. After the explosion, as a result of technical shortcomings of the platform, the anti-reset fuse, which was supposed to automatically plug the oil well, did not work.
In mid-September 2010, a report by the Bureau of Ocean Resources Management, Regulation and Conservation and the US Coast Guard was published. It contained 35 causes of the accident, with BP identified as the sole culprit in 21 of them. In particular, the main reason cited was the neglect of safety standards to reduce well development costs. In addition, the platform employees did not receive comprehensive information about the work at the well, and as a result, their ignorance was superimposed on other errors, which led to the well-known consequences. In addition, the reasons cited were poor well design that did not provide sufficient barriers to oil and gas, as well as insufficient cementing and changes made to the well development project at the very last moment.
Transocean Ltd, the owners of the oil platform, and Halliburton, which carried out the underwater cementing of the well, were named as partly to blame.
Litigation and compensation
The Mexican oil spill trial against the British company BP began on February 25, 2013 in New Orleans (USA). In addition to federal claims, British company lawsuits were filed by American states and municipalities.
A federal court in New Orleans has approved the amount of fines that BP must pay for the accident in the Gulf of Mexico in 2010. The fine will be $4.5 billion. BP will pay the amount over five years. Almost $2.4 billion will be transferred to the National Fish Fund and wildlife USA, 350 million - National Academy of Sciences. In addition, according to the claims of the Commission on securities and US exchanges will be paid $525 million over three years.
On December 25, 2013, the US Court of Appeal ruled that, despite the appeals filed, the British corporation BP must continue to pay claims of organizations and individuals, despite unproven facts of losses as a result of the oil spill. Initially, BP admitted its guilt in the incident only partially, placing part of the responsibility on the platform operator Transocean and subcontractor Halliburton. Transocean agreed in December 2012, but continues to insist that BP bears full responsibility for the accident on the platform.
Environmental implications
After the accident, one-third of the Gulf of Mexico was closed to fishing, and an almost complete ban on fishing was introduced.
Photo: www.globallookpress.com
1,100 miles of state coastline from Florida to Louisiana were polluted, and dead marine life was constantly found on the shore. In particular, about 600 sea turtles, 100 dolphins, more than 6,000 birds and many other mammals were found dead. As a result of the oil spill, mortality among whales and dolphins increased in subsequent years. According to ecologists, the mortality rate of bottlenose dolphins has increased 50 times.
Tropical coral reefs located in the waters of the Gulf of Mexico also suffered enormous damage.
Oil has even seeped into the waters of coastal reserves and marshes that play important role in maintaining the vital activity of wildlife and migratory birds.
According to recent studies, today the Gulf of Mexico has almost completely recovered from the damage it suffered. American oceanologists monitored the growth of reef-forming corals, which cannot live in polluted water, and found that the corals reproduce and grow in their usual rhythm. Biologists note a slight increase average temperature waters in the Gulf of Mexico.
Some researchers have expressed concerns about the impact of the oil accident on the climate-forming Gulf Stream. It was suggested that the current cooled by 10 degrees and began to break into separate undercurrents. Indeed, some weather anomalies (such as severe winter frosts in Europe) have occurred since the oil spill occurred. However, scientists still do not agree on whether the disaster in the Gulf of Mexico is the primary cause of climate change and whether it affected the Gulf Stream.
The explosion on the Deepwater Horizon drilling platform was bound to happen and was just waiting for its moment. Experts now name seven fatal mistakes that caused the oil spill in the Gulf of Mexico. There are some lessons that can be learned from this disaster to help avoid something like this in the future.
On April 21, 2010, in the Gulf of Mexico, rescue ships confront the inferno that broke out on the Deepwater Horizon drilling platform. The fire is fueled by oil and gas coming from an underwater well, which exploded the day before at a depth of 5.5 km below the deck of this platform
April 20 was a day of triumph for British Petroleum and the crew of Transocean's Deepwater Horizon drilling platform. A floating drilling platform 80 km off the coast of Louisiana at a point where the water depth was 1.5 km has almost completed drilling a well that extends 3.6 km below the ocean floor. It was such a difficult task that it was often compared to going to the moon. Now, after 74 days of continuous drilling, BP was preparing to cap the Macondo Prospect well until all production equipment was in place to ensure a regular flow of oil and gas. At about 10:30 a.m., the helicopter brought in four senior officials—two from BP and two from Transocean—to celebrate the completion of the drilling operation and seven years of trouble-free operation of the drilling platform.
Over the next few hours, events unfolded on the platform that would be worthy of inclusion in safety textbooks. Like the partial meltdown of the reactor core at nuclear power plant Three Mile Island in 1979, a toxic leak at a chemical plant in Bhopal (India) in 1984, the destruction of the Challenger and Chernobyl disaster in 1986, these events were not caused by one wrong step or breakdown in a specific unit. The Deepwater Horizon disaster was the result of a whole chain of events.
On April 21, 2010, in the Gulf of Mexico, rescue ships confront the inferno that broke out on the Deepwater Horizon drilling platform. The fire is fueled by oil and gas coming from an underwater well - it exploded the day before at a depth of five and a half kilometers below the deck of this platform.
Self-soothing
Deepwater wells have been operating without problems for decades on end. Of course, underwater drilling is a complex task, but there are already 3,423 operating wells in the Gulf of Mexico alone, and 25 of them are drilled at depths of more than 300 m. Seven months before the disaster, the same drilling platform drilled four hundred kilometers southeast of Houston the world's deepest well, going under the ocean floor to a fantastic depth of 10.5 km.
What was impossible a few years ago has become a routine procedure. BP and Transocean broke record after record. The same offshore drilling technology and the same equipment, which have proven themselves to be excellent in shallow water developments, are quite effective, as practice has shown, at deeper depths. Oil workers, like a gold rush, rushed into the ocean depths.
British Petroleum (BP) leases drilling platforms owned by Swiss company Transocean. With their help, she makes her way to a hydrocarbon field called Macondo Prospect. This field is located 80 km southeast of the city of Venice (Louisiana) at a depth of 3.9 km under the ocean floor (the ocean depth in this place is one and a half kilometers). Potential reserves - 100 million barrels (medium-sized field). BP plans to complete all drilling operations in 51 days.
Pride set the stage for the disaster that happened on the rig. “If a well unexpectedly begins to flow, creating an oil spill, there should be no fear of serious consequences, since the work is carried out in accordance with accepted industry standards, proven equipment is used and there are techniques specifically developed for such cases...” - as written in the exploration plan, which BP submitted on March 10, 2009 to the American supervisory authority, the Minerals Managements Service (MMS) of the US Department of Mineral Resources. Spontaneous blowouts of underwater wells happen all the time; in the Gulf of Mexico alone, from 1980 to 2008, 173 cases were recorded, but not a single similar blowout has ever occurred in deep water. In fact, neither BP nor its competitors had any “proven equipment” or “specially developed techniques” for such an eventuality - no insurance plan at all in anticipation of any catastrophic accident at great depths.
October 7, 2009
BP begins drilling on a 2,280-hectare site leased back in 2008 for $34 million. However, the original Marianas drilling rig was damaged by Hurricane Ida, so it is towed to the shipyard for repairs. It takes three months to replace it with the Deepwater Horizon platform and resume work.
February 6, 2010
Horizon begins drilling operations at the Macondo field. To keep up with the schedule, workers are in a hurry, increasing the drilling speed. Soon, due to excessive speeds, the walls of the well crack and gas begins to leak inside. Engineers seal the bottom 600 meters of the well and reroute the well. These alterations cost a two-week delay.
Mid March
Mike Williams, Transocean's chief electronics officer, asks subsea operations manager Mark Hay why the control panel's throttle shut-off functions are simply turned off. According to Williams, Haye replied: “We all do it that way.” The year before, Williams noticed that on the rig, all emergency lights and indicators were simply turned off and would not be automatically activated when a gas leak or fire was detected. In March, he saw a worker holding pieces of rubber taken out of a well. It was debris from a vital cylindrical valve—one part of a blowout preventer, a multi-story structure of safety valves installed above the wellhead. According to Williams, Haye said, "It's no big deal."
March 30, 10:54
BP engineer Brian Morel sends an email to a colleague discussing an idea for running a single 175mm casing string into a well, extending from the wellhead all the way to the bottom. A safer option with a liner, which provides more stages of protection from gas rising through the well, Morel notes: “By doing without a liner, you will save a lot of time and money.” But if a liner were used, says Ford Brett, a longtime petroleum engineer, "the well would be much better protected from all sorts of trouble."
April 9
Ronald Sepulvado, who is supervising the well work on behalf of BP, reports that a leak was discovered in one of the control devices for the preventer, which is supposed to receive an electronic signal from the platform to shut off the well and give a command to the hydraulic drives for emergency killing of the wells. In such situations, BP is required to notify MMS and suspend drilling operations until the block is brought into compliance. working condition. Instead, to plug the leak, the company switches the faulty device to the “neutral” position and continues drilling. Nobody notified MMS.
14th of April
BP is submitting a request to MMS for the option of using a single string instead of the safer liner method. The next day she receives approval. Two more additional requests were agreed upon in a matter of minutes. Since 2004, 2,200 wells have been drilled in the Gulf, and only one company managed to finalize approvals for three changes to work plans within 24 hours.
frivolity
For years, BP prided itself on its ability to take on risky ventures in politically unstable states (such as Angola and Azerbaijan), its ability to implement sophisticated technological solutions in the remotest corners of Alaska or enormous depths in the Gulf of Mexico. As Tony Hayward, the company's former CEO, said, "We do what others can't or don't dare do." Among oil producers, this company was famous for its frivolous attitude towards safety issues. According to the Center public safety(Center for Public Integrity), from June 2007 to February 2010 at BP refineries in Texas and Ohio, of 851 safety violations, 829 were determined to be “knowingly” or “maliciously” by OSHA.
The Deepwater Horizon disaster is not the only large-scale oil spill blamed on BP. In 2007, its subsidiary BP Products North America paid more than $60 million in fines for violating federal environmental laws in Texas and Alaska. The list of these violations also includes the largest spill in 2006 in the Arctic Lowland (1000 tons of crude oil), when the cause was the company’s reluctance to take adequate measures to protect pipelines from corrosion.
Other oil producers have told Congress that BP's drilling programs do not meet industry standards. “They did not fulfill all the requirements that we would recommend or apply in own practice" says John S. Watson, president of Chevron.
The Deepwater Horizon platform burned for a day and a half and finally sank into the waters of the Gulf of Mexico on April 22.
Risk
Oil and methane in deep deposits are under pressure - just move them and they can shoot out in a fountain. How deeper well, the higher the pressure, and at a depth of 6 km the pressure exceeds 600 atm. During the drilling process, a drilling fluid loaded with mineral fractions, which is pumped into the well, lubricates the entire drill string and washes drilled rock to the surface. The hydrostatic pressure of the heavy drilling fluid holds liquid hydrocarbons within the reservoir. Drilling fluid can be considered the first line of defense against an oil blowout.
If oil, gas or plain water get into the well during drilling (say, due to insufficient density of the drilling fluid), the pressure in the well will rise sharply and the possibility of a blowout will arise. If the borehole walls are cracked or the cement layer between the casing protecting the drill string and the rock in the borehole wall is not strong enough, gas bubbles can roar up the drill string or outside the casing, entering the string at joints. This can cause the well walls to crack, creating opportunities for leaks, says Philip Johnson, professor of civil engineering at the University of Alabama.
At the base of the well, cement slurry is supplied from inside the casing and rises up the annulus. Cementing is necessary to protect the well and prevent leakage.
Neither the oil workers nor the MMS service thought about the fact that when drilling in increasingly difficult conditions the risk will increase. “There is a clear underestimation of the threatening dangers,” says Steve Arendt, vice president of ABS Consulting and an oil refining safety expert. “A long chain of successes has blinded the drillers. They were simply not ready.”
Violations
BP's decisions were based on what Robert Bea, a professor at the University of California at Berkeley, calls "normalizing disruption." The company has long been accustomed to operating on the edge of what is acceptable.
Mid April
The review of BP's plan recommended against using a single casing because it creates an open annulus all the way to the wellhead (the gap between the steel casing and the well wall). In such a situation, the preventer remains the only barrier to the gas flow if the cement fill fails. Despite this caveat, BP decided to install a single steel casing.
April 15
Drilling is completed, and the platform is about to pump fresh mud into the well so that the used mud rises from the bottom of the well to the drilling platform. In this way, gas bubbles and rock debris can be brought out - they would weaken the cement fill, which should subsequently fill the annular space. In the Macondo version, this procedure should take 12 hours. BP cancels its own work plan and allocates only half an hour to circulate the drilling fluid.
April 15, 15:35
Halliburton spokesman Jesse Gagliano sends BP an email recommending the use of 21 centralizers—special clamps that center the casing in the well, ensuring an even cement pour. In the end, BP makes do with just six centralizers. John Hyde, who led BP's well services team, admitted that the centralizers were not the type required for the job. “Why couldn’t you wait until the centralizers you needed arrived?” - asked the lawyer. “But they were never brought,” Hyde replied.
Completion of the work was constantly delayed, and the work organizers were under intense pressure. Drilling began on October 7, 2009, using the Marianas platform first. It was heavily damaged by the November hurricane. It took three months to bring in the Horizon platform and continue drilling operations. 78 days were allotted for all work at a cost of $96 million, however real time announced 51 days. The company demanded pace. But in early March, due to the increased drilling speed, the well cracked. The workers had to reject a 600-meter section (out of 3.9 km drilled by that time), fill the defective section with cement and make their way around the oil-bearing layer. By April 9, the well had reached the planned depth (5600 m from the drilling platform level and 364 m below the last cemented casing segment).
The well is being drilled in stages. Workers work their way through the rock, install another segment of casing, and pour cement into the gap between the casing and the surrounding rock. This process is repeated over and over again, the casing pipes becoming smaller and smaller in diameter. To secure the last section, the company had two options - either run a single row of casing from the wellhead to the bottom, or run a liner - a short string of pipes - under the shoe of the lower section of already cemented casing, and then push further a second steel casing, which called the shank extension. The option with an extension was supposed to cost 7-10 million more than a single column, but it significantly reduced the risk by providing a double barrier to gas. A congressional investigation found that internal BP documents dating back to mid-April included recommendations that single-row casing was not recommended. Yet on April 15, MMS responded positively to BP's request to amend the permit application. This document stated that the use of single-row casing strings "has strong economic reasons" In shallow water, single row strings are used quite often, but they have hardly been used in deepwater exploration wells such as Macondo, where the pressure is very high and geological structures insufficiently studied.
As the casing pipes are lowered, spring clamps (called centralizers) hold the pipe along the axis of the wellbore. This is necessary so that the cement fill is placed evenly and no cavities are formed through which gas could escape. On April 15, BP notified Halliburton's Jess Galliano that six centralizers were expected to be deployed on the final 364 m of casing. Galliano ran an analytical simulation model on a computer, which showed that 10 centralizers would give a situation with a “moderate” risk of gas breakthrough, and 21 centralizers could reduce the probability of an unfavorable scenario to “small.” Galliano recommended BP specifically last option. Gregory Waltz, BP's drilling engineering team leader, wrote to John Hyde, well services team leader: "We've located 15 Weatherford centralizers in Houston and got the rig issues sorted out so we can send them out by helicopter in the morning...." But Hyde countered: " It will take 10 hours to install them... I don’t like all this and... I doubt whether they are needed at all.” On April 17, BP informed Galliano that the company had decided to use only six centralizers. With seven centralizers computer model showed that “in a well it is possible serious problems with a gas breakthrough,” but the $41,000 per hour of delay outweighed it, and BP chose the option with six centralizers.
A preventer is a stack of valves 15 m high, designed to plug an out-of-control well. For reasons still unknown, this last line of defense refused to work at the Macondo field.
After cement is pumped into the well, acoustic flaw detection of cementation is carried out. On April 18, a team of flaw detectors from Schlumberger flew to the drilling site, but BP refused their services, violating all possible technical regulations.
Technique
Meanwhile, at the rig, everyone is working like crazy, not seeing anything around them and not being guided by anything other than justification considerations and the desire to speed up the process. Galliano made clear the possibility of gas leaks, and such leaks increase the risk of a blowout. However, his models could not prove to anyone that this release would definitely happen.
April 20 0:35
Workers pump cement slurry down the casing, then use drilling mud to push the cement up from the bottom to a height of 300 m in the annulus. All of these actions comply with MMS regulations for sealing hydrocarbon deposits. Halliburton uses nitrogen-rich cement. This solution adheres well to rocks, but requires very careful handling. If gas bubbles penetrate into unset cement, they will leave channels through which oil, gas or water can enter the well.
April 20 – 1:00 – 14:30
Halliburton conducts three high-pressure tests. The pressure is increased inside the well and checked whether the cement filling holds well. Two tests were taken in the morning and afternoon. All is well. Contractors were sent back to the platform for a 12-hour acoustic flaw inspection of the cement grout. "It was a terrible mistake," says Satish Nagarajaya, a professor at Rice University in Houston. “That’s where they lost control of events.”
The last line of defense for deepwater wells is the blowout preventer, a five-story tower of valves built on the ocean floor above the wellhead. It must, if necessary, shut off and plug a well that is out of control. True, the preventer at the Macondo well was non-functional; one of its pipe rams - plates covering the drill string and designed to prevent gases and liquids rising through the preventer - was replaced with a non-working prototype. Drilling rigs often allow themselves such replacements - they reduce the cost of testing mechanisms, but they have to pay with increased risk.
The investigation also revealed that one of the control panels for the preventer had a dead battery. A signal from the console triggers a cutting ram, which should simply cut the drill string and plug the well. However, even if there was a freshly charged battery on the remote control, the cutting die would hardly have worked—it turned out that one of the hydraulic lines at its drive was leaking. The MMS rules are unequivocal: “If any of the available control panels for the blowout preventer are not operational,” the drilling platform “must suspend all further operations until the faulty control panel is brought into operation.” Eleven days before the blowout, a responsible BP representative present on the platform saw a mention of a hydraulic leak in the daily work report and alerted headquarters in Houston. However, the company did not stop work, begin repairs, or notify MMS.
April 20, 17:05
The lack of fluid rising up the riser makes it clear that the annulus preventer has leaked. Soon after this, the drilling rig performs pressure testing of the drill string with negative pressure. At the same time, they reduce the pressure of the drilling fluid in the well and see if hydrocarbons have made their way through the cement or casing. The result indicates that a leak may have developed. It was decided to retest. Typically, before such a test, workers install a sealing sleeve to more securely attach the upper end of the casing to the preventer. IN in this case BP didn't do this.
April 20, 18:45
A second test with negative pressure confirms the fears. This time, the clue is discovered by measuring the pressures on the various pipelines that connect the platform and the BOP. The pressure in the drill string is 100 atmospheres, and in all other pipes it is zero. This means that gas is entering the well.
April 20, 19:55
Even with these test results in hand, BP orders Transocean to replace the 1,700 kg/m3 drilling fluid in the riser and top of the casing with seawater with a density of just over 1,000 kg/m3. At the same time, it was necessary to place a cement plug in the well at a depth of 900 m below the ocean floor (the drilling fluid supply line). Carrying out these two operations at the same time is fraught with a certain risk - if the cement plug does not seal the well, the drilling fluid itself will act as the first line of defense against a blowout. An investigation led by BP itself will describe the decision as a “fundamental mistake.”
Management
By April 20, having left the cementing of the well on the last three hundred meters of casing unchecked, workers were preparing to seal the Macondo well. At 11 o'clock in the morning (11 hours before the explosion) an argument broke out at the planning meeting. Before plugging the well, BP intended to replace the protective mud column with lighter seawater. Transocean objected vigorously, but eventually succumbed to pressure. The dispute also centered on whether negative pressure testing (reducing the pressure in the well and seeing if gas or oil flows into it) should be carried out, although this procedure was not included in the drilling plan.
The dispute revealed a conflict of interest. BP pays Transocean $500,000 daily to rent the platform, so it is in the tenant's interest to carry out the work as quickly as possible. On the other hand, Transocean can afford to spend some of these funds on safety concerns.
20 April 20:35
Workers pump 3.5 cubic meters each sea water per minute to flush the riser, however, the speed of the incoming drilling fluid jumps to 4.5 cubic meters per minute. "It's pure arithmetic," says petroleum geologist Terry Barr. “They needed to realize that the well was leaking and that they had to desperately pump the drilling fluid back in to plug it.” Instead, workers continue to pump in seawater.
April 20, 21:08
Workers turn off a pump that pumps seawater to perform an EPA-mandated "shimmer test" to check for floating oil on the sea surface. No oil was found. The pump does not work, but liquid continues to flow from the well. The pressure in the casing increases from 71 atmospheres to 88. Over the next half hour, the pressure increases further. Workers stop pumping water.
April 20, 21:47
The well explodes. Gas under high pressure breaks through the preventer and reaches the platform along the riser. A seventy-meter geyser gushes at the top of a drilling rig. Behind it falls a snow-like porridge, “smoking” from evaporating methane. The blocked general alarm system meant that the workers on deck did not hear any warning of the approaching disaster. Bypass circuits on the control panel caused the system designed to shut down all the engines on the rig to fail.
Transocean performed two negative pressure testing cycles and installed a cement plug to seal the wellhead. At 19:55, BP engineers decided that the plug had already set and ordered Transocean workers to open a cylindrical valve on the preventer to begin pumping seawater into the riser. The water would displace drilling fluid, which was pumped to the support vessel Damon B. Bankston. At 20:58, the pressure in the drill string increased. At 9:08 p.m., as pressure continued to rise, workers stopped pumping.
April 20, 21:49
The gas flows down chutes into the mud pit, where a couple of engineers scramble to pump more mud into the well. Diesel engines swallow gas through their air intakes and go haywire. Engine #3 explodes. It begins a chain of explosions that rock the platform. Both engineers die instantly, four more die in the room with the shakers. In addition to them, five more workers died.
April 20, 21:56
A worker on the bridge presses the red button on the emergency shut-off console to turn on the shear rams, which should shut off the well. But the dies didn't work. The preventer has a battery that powers the emergency switches and triggers the rams in the event of damage to communication lines, hydraulic lines or electrical cables. It was later determined that the hydraulic line was fine; BP believed the switch had failed. The command at the rig calls a vessel for evacuation.
After a six-minute break, workers at the rig continued pumping seawater, ignoring the pressure surges. At 21:31 the download was stopped again. At 9:47 p.m., monitors showed a “significant surge in pressure,” and a few minutes later a stream of methane erupted from the drill string and the entire platform turned into a giant torch—not yet lit. Then something flashed green light, and a white boiling liquid - a foamed mixture of drilling fluid, water, methane and oil - stood in a column above the drilling rig. First Officer Paul Erickson saw “a flash of flame directly above the jet of liquid,” and then everyone heard the distress call “Fire on the platform! Everyone leave the ship! Throughout the rig, workers were scurrying around, trying to get onto the two serviceable rescue boats. Some shouted that it was time to let them down, others wanted to wait for those lagging behind, and others jumped into the water from a height of 25 m.
Photo: Two days after the blowout, a remote-controlled robot attempts to seal the out-of-control Macondo well.
Meanwhile, on the bridge, Captain Kurt Kuchta was arguing with the director of underwater operations over whose right to launch the emergency shutdown system (it should give a command to cut off the rams, thus sealing the well and breaking the connection between the drilling platform and the drill string). The system took a full 9 minutes to start up, but it didn’t matter anymore, since the preventer still didn’t work. The Horizon platform remained disconnected; oil and gas continued to flow from the ground, fueling the blazing inferno that soon surrounded the rig.
And here is the result - 11 dead, billions of losses for BP, ecological catastrophy in the Gulf. But the worst part, says Ford Brett, president of Oil and Gas Consultants International, is that the blowout “isn't a disaster in the traditional sense. This is one of those accidents that was completely preventable."
Explosion of the Deepwater Horizon oil platform An accident that occurred on April 20, 2010, 80 kilometers off the coast of Louisiana in
Gulf of Mexico on the Deepwater Horizon oil platform in the Macondo field.
The oil spill that followed the accident became the largest in US history and turned the accident into
one of the largest man-made disasters By negative influence on the environmental situation.
The explosion at the Deepwater Horizon installation killed 11 people and injured 17 out of 126
people on board. At the end of June 2010, there were reports of the death of 2 more
people during the liquidation of the consequences of a disaster.
Through damage to well pipes at a depth of 1500 meters into the Gulf of Mexico in 152 days
About 5 million barrels of oil spilled, the oil slick reached an area of 75 thousand
square kilometers.
Causes and culprits of the tragedy
According to an internal investigation conducted by employeessafety of BP, errors were cited as the cause of the accident
working personnel, technical faults and design errors
the oil platform itself. The prepared report stated that
rig employees misinterpreted measurement readings
pressure when checking the well for leaks, resulting in flow
hydrocarbons rising from the bottom of the well filled the drilling platform
through ventilation. After the explosion, as a result of technical deficiencies
platform, the anti-reset fuse did not work, which
was supposed to automatically plug an oil well.
Oil spill
From April 20 to September 19, liquidation of the consequences of the accident continued. Themover time, according to some experts, about
5000 barrels of oil. According to other sources, up to 100,000 barrels fell into the water
per day, as announced by the US Secretary of the Interior in May 2010. By the end
In April, the oil slick reached the mouth of the Mississippi River, and in July 2010
oil was discovered on the beaches of the US state of Texas. Besides,
the underwater oil plume stretched 35 km in length at a depth of more than
1000 meters. In 152 days into the waters of the Gulf of Mexico through damaged
The well pipes spilled about 5 million barrels of oil. Oil area
spots amounted to 75 thousand km².
Environmental implications
Brown pelican covered in a thick layeroil, floating in the sea surf
coast of East Grande Terre Island, state
Louisiana.
Dead fish on the beach of Grand Isle, Louisiana.
The British Petroleum company uses chemical reagents -
so-called dispersants that break down oil. However, their
use leads to water poisoning. Dispersants
destroy the circulatory system of fish, and they die from
heavy bleeding. The oil-covered body of a dead dolphin lies on
land in Venice, Louisiana. This dolphin
spotted and picked up while flying over the southwest Mississippi River area.
American Brown Pelican (left), standing next to
with their pure brothers on one of the islands in
Barataria Bay. They nest on this island
numerous bird colonies. Oil-covered dead fish float off the coast
East Grand Terre Island June 4, 2010 near East Grand Terre Island, Louisiana. Fish eats
contaminated due to the use of dispersants
plankton, and food chain toxins
are spreading everywhere.
The oil-covered carcass of a northern gannet on
beach on Grand Isle, Louisiana.
The state's coast was the first to encounter oil
film and suffered most from this
disasters.
About the consequences
As a result of the oil spill, 1,770 kilometers of coastline were contaminated, and a ban onfishing, more than a third of the entire water area of the Gulf of Mexico was closed to fishing. From
all US states with access to the Gulf of Mexico were hit hardest by oil
The states affected were Louisiana, Alabama, Mississippi and Florida.
As of May 25, 2010, 189 dead were found on the Gulf Coast
sea turtles, many birds and other animals, at that time the oil spill threatened more than 400
species of animals, including whales and dolphins.
As of November 2, 2010, 6,814 dead animals had been collected, including 6,104 birds,
609 sea turtles, 100 dolphins and other mammals, and one reptile of another species.
According to the Office of Specially Protected Resources and the National Oceanic Administration
atmospheric management in 2010-2011 recorded an increase in cetacean mortality
in the northern Gulf of Mexico several times compared to previous years (2002-2009
years).
Dealing with the consequences
The work to eliminate the oil spill was coordinated by a special group underleadership of the US Coast Guard, which included
representatives of various federal departments.
As of April 29, 2010, a flotilla participated in the rescue operation
BP, consisting of 49 tugs, barges, rescue boats and other vessels, also
used 4 submarines. On May 2, 2010, 76 people already took part in the operation
ships, 5 planes, about 1100 people, 6000 were also involved
military personnel of the US National Guard, military personnel and equipment of the US Navy and Air Force USA.