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Live video link from the ROV monitoring the damaged riser
Total size of spill
Timeline:
Week 1Apr 20 - The Deepwater Horizon (DWH) drilling rig owned by Swiss-based Transocean and leased by British Petroleum (BP) explodes.BP said it appeared to be a blowout, in which natural gas or oil forces its way up a well pipe and smashes the equipment. A special blowout preventer (BOP) that sits on the top of the Deepwater Horizon (MC252) wellhead on the seafloor apparently failed. The well is located 1 mile deep in the Mississippi Canyon, 60 miles southeast of the Mississippi delta and 120 miles south of the Mississippi and Alabama coast. Bob Fryar, senior vice president of BP's exploration and production business in Angola, brought in for his expertise in deep water drilling said: "there is nothing unique about the situation that was taking place at the time that would have prohibited the blowout preventer (BOP) system from working as designed." "There are electrical systems driving the hydraulic pumps, with air system backups. There are battery backups for power," David O'Donnell, an oilfield equipment consultant, said. "Somehow they lost it all, or didn't have enough time to activate."
Subsequent analysis showed there was a hydraulic leak and failed battery that was supposed to activate a so-called "deadman" trigger, that contributed to the failure of the blowout preventer. Conflicting pipe pressure tests should have warned those on the rig that poor pipe integrity may have been allowing explosive methane gas to leak into the well. The well in Tuesday's accident was the first of a series to be drilled and was in the process of being temporarily plugged pending production. "The well had been cased off. We were actually in process of running the final plug," David Rainey, BP vice president, said. "At this point, we don't understand what happened."
There are three sources of oil. The largest at the end of the riser which was attached to the rig on the surface, the second where the riser attached to the blowout peventer (BOP) and the third at the end of a drill pipe. The drill pipe was capped on May 5. Apr. 23 - The U.S. coastguard said it thought it was dealing only with a surface residual oil spill from the rig. Apr. 24 - Images provided by the U.S. Coast Guard shows oil leaking from the drill pipe 5,000 ft. under the ocean surface. The rate was estimated at 1,000 barrels per day. (See updated estimates below)
Apr. 26
Other solutions under consideration: - Lowering a second blowout preventer onto the damaged one to seal the well - Drill a relief well near it to relieve pressure and reduce the size of the leak. Started 5/2/2010 3 months - $100 Million Week 2Apr 29 Suttles on CBS's "Early Show" says "we think the range has increased" to "somewhere between 1,000 and 5,000 barrels" per day."Apr 30 - The seas were too rough and the winds too strong Friday to burn off the oil, suck it up effectively with skimmer vessels, or hold it in check with the miles of orange and yellow inflatable booms strung along the coast. The floating barriers broke loose in the choppy water, and waves sent oily water lapping over them.
The Coast Gard and NOAA (National Oceanic and Atmospheric Administration) say the well is leaking 5,000 barrels (210,000 gallons) per day. A lawsuit filed a week after the explosion by an injured technician on the platform claims that Halliburton improperly cemented the well. Cementing is a process in which a slurry is used to fill the gap between the drilled hole and the casing, or the pipe that brings oil and gas up out of the ground. May 2 - Another rig is moved into place to start drilling a relief well. May 3 - Winds die down and oil stops moving towards the coast. Week 3May 5 - BP has finally managed to put a cap on a leaking drill pipe lying on the Gulf floor. But it will not significantly reduce the amount of oil, which is coming from two other leaks.The New York Times reports "In a closed-door briefing for members of Congress, a senior BP executive conceded Tuesday that the ruptured oil well could conceivably spill as much as 60,000 barrels a day of oil, more than 10 times the estimate of the current flow. "The rate could go up to that," Mr. Suttles of BP said, when asked to verify a report in The Times. "It's not the situation we have at this moment, but it's not impossible."
May 8-9 - Lowered a containment box over the leak but it got clogged up with a large volume of hydrates - icelike crystals formed when gas combines with water - accumulated inside the vessel and it would not funnel the oil to ships on the surface as planned, so they had to remove it.
May 10 Current plans: - Junk shot - Inject junk - shredded up tires, golf balls, rope and things like that - into the BOP at high pressure to clog it up. I've seen several explanations of this: 1. It would be used before the top kill (below) to clog up leaks at the top of the BOP. 2. It would be used as a last resort if the Top Kill doesn't work to plug up the whole thing. BP doesn't like the term "junk shot". They will be replacing a control pod with electronics at the top of the BOP so they can fix some of the problems in operating the valves, necessary for this to work.
- Top Kill - Pump drilling mud down the well under high pressure to stop the flow followed by concrete to permanently seal it. Diagram Top Kill and junk shot are attempted at the end of week 5. Week 4May 13 At the request of NPR, Steven Wereley, an associate professor of mechanical engineering at Purdue University, analyzed videotape of the seafloor gusher using a technique called particle image velocimetry and came up with an value for the rate of the oil spill from 56,000 barrels to 84,000 barrels a day. Their findings suggest the BP spill is already far larger than the 1989 Exxon Valdez accident in Alaska, which spilled at least 250,000 barrels of oil. See: Gulf Oil Spill May Far Exceed Government, BP Estimates : NPR and Calculations of Gulf Spill Volume Are Questioned - NYTimes.comBP says it is difficult to measure the volume of oil at the leak source because of the high ratio of gas to oil coming out of the well. May 16 Shore damage still small. Some oil balls.
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May 18  The Loop Current's influence has pulled the oil at the ocean surface toward the southeast away from the original oil spill area. From there it could be carried around Florida and up the east coast in the gulf stream.See: Oil Spill Encounters Loop Current - weather.com The riser insertion tube tool (RITT) containment system that was put into place in the end of the leaking riser is operational. It is estimated to be collecting and carrying about 2,000 barrels a day (b/d) of oil to flow up to the drillship Discoverer
The Environmental Protection Agency (EPA) asked BP to stop using the dispersant, known as Corexit, and find a safer alternative. BP disputed the agency's assessment of its level of toxicity, and the environmental agency asked the oil giant to at the very least reduce the amount it was using. Week 6May 25: Other strategies:If the top kill and junk shot don't work, BP has proposed some other options: 1. Second BOP - Placing another blow out preventer on top of the existing blow out preventer. 2. The Lower Marine Riser Package (LMRP) option would cut the riser off the top of the BOP, and use the top hat that is sitting on the sea bed near the well, to capture the flow from the top of the BOP. See BP Press Release: 5/25, 5/26
Dealing with the oil along the coast:
Human hair stuffed into nylon stockings is being collected for its efficiency at absorbing large amounts of oil. See article at www.dailymail.co.uk May 26:
BP starts the top kill process; Pumping drill mud into the well thru valves on the side of the BOP, followed by concrete to stop the flow.
May 27: Reporting from Houma, La. U.S. Coast Guard Adm. Thad Allen, the federal government's top oil-spill commander, said:--
Engineers have at least temporarily stopped the flow of oil and gas into the Gulf of Mexico from a gushing BP well.
The preliminary best estimate of the volume of oil flowing was released by the semi-official Flow Rate Technical Group (FRTG) (A group of government and academics who are tasked with providing the government with an independent scientific assessment of the scope of the disaster.) put the volume of oil flowing from the blown-out well at 12,000 to 19,000 barrels (500,000 to 800,000 US gallons) per day, which had amounted to between 18 and 29 million US gallons, surpassing the Exxon Valdez spill of 11 million gallons. President Obama announces that the Federal Government is in charge, and has been doing all they can. He also announced major new restrictions on drilling projects, and the head of the federal agency that regulates the industry resigned under pressure, becoming the highest-ranking political casualty of the crisis so far.
May 28: U.S. Coast Guard approves construction of 'prototype' sand berm to fight oil spill. The initial berm would be 3 to 5 miles long in a broad region somewhere between Grand Isle and Venice. If it works the berm could be extended to cover 45 miles of berms on barrier islands, as approved by the U.S. Army Corps of Engineers. Governor Bobby Jindal proposed 100 miles of berms at an estimated cost of $350 million--to be paid for by BP. BP made a third attempt at what is termed the "junk shot" Friday night (5/28), a procedure that involves pumping odds and ends like plastic cubes, knotted rope, and golf balls into the blowout preventer, the five-story safety device atop the well. The maneuver is complementary to the heavily scrutinized effort known as a "top kill,"which began four days ago and involves pumping heavy mud into the well to counteract the push of the escaping oil.
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May 30:
A BP executive says a relief well is the "end point" of efforts to stop the Gulf oil spill -- which suggests there's little chance of plugging the leak until the new well is completed in August.The relief well will intersect the existing well about 13,000 feet below the ocean floor (18,000' below the surface) just above the oil rservoir. Heavy fluid will be pumped in to stop the flow then cement will be added to seal the well. Drilling of the first relief well continues and is currently at 12,090 feet. Drilling of the second relief well is temporarily suspended and is expected to recommence shortly from 8,576 feet. Large diagram  Images © BP p.l.c.
Week 7June 2:Coast Guard Adm. Thad Allen, said there was a problem with cutting the riser pile and BP had to settle for a rougher cut, making a tighter seal less likely. They will try to attach the Lower Marine Riser Package (LMRP) Cap Containment System, which will fit over the cut off riser and send the oil to a ship above in the next couple of days. "There could be a temporary 20% increase in the volume of oil spilling from the well. That's because the company has cut off a kink in the pipe that currently seems to be holding back some of the gusher." Said Carol Browner, Energy Advisor for the White House. Technical Briefing by BP (pdf)
June 4: Tar balls from the spill wash up on some Florida beaches.
June 5: Coast Guard Adm. Thad Allen, said that even after the relief wells stop the flow completely and a cement cap is in place the oil will be out there for months to come. "This will be well into the fall. This is a siege across the entire Gulf," he said. While U.S. federal governments Flow Rate Technical Group (FRTG) insist that 12,000 to 19,000 barrels per day is still the official estimate of the amount of oil spewing from the BP well in the Gulf of Mexico, a draft report obtained by The Phoenix Sun, shows that a key government panel concluded that "at least" 12,000 to 25,000 barrels of oil per day was flowing from the well in May. The Plume Calculation Team (PCT), one of two teams in the FRTG, added that it did not have enough data at the time to make an upper boundary estimate of the total amount of oil coming from the well. Week 8June 8:BP captured 15,000 barrels on Monday, which is the maximum rate for the capture ship. U.S. Coast Guard Admiral Thad Allen said at a news conference in Washington that BP is working to increase processing capacity at a drillship and a service rig at the water's surface to 28,000 barrels per day. See June 10. They will eventually burn it because they don't the shipping capacity to remove all the oil. University of South Florida, researchers confirmed Tuesday that plumes of dispersed oil were spreading far below the ocean surface from the leaking well in the Gulf of Mexico, raising fresh concern about the potential impact of the spill on sea life. BP's chief operating officer, Doug Suttles, continued to insist Wednesday morning on the "Today" show on NBC that no underwater oil plumes in "large concentrations" have been detected from the spill, saying that it "may be down to how you define what a plume is here." Samantha Joye of the University of Georgia, supplied additional information. The top of the plume is about 3,600 feet below the sea surface; the plume is three miles wide and as thick as 1,500 feet in spots, she said.
June 10:
Short term plan:
June 11: Week 9
June 16: The FRTG concluded that the most likely flow rate of oil today is between 35,000 and 60,000 barrels per day. Four days of intense negotiations between the White House and BP lawyers allowed President Obama to announce Wednesday that the oil giant would create a $20 billion fund to pay damage claims to thousands of fishermen and others along the Gulf Coast. See NY Times. BP began collecting crude oil on Wednesday from a second containment system.  Source: Gulf Oil Spill, by the Numbers - CBS News Current Trajectory Maps at NOAA (National Oceanic and Atmospheric Administration)
Current Trajectory Maps at NOAA Size of spill: Barrels/day 5,000 70,000 6 weeks 9 M gallons 126 M gallons 3 months 19 M gallons 266 M gallons (Exxon Valdez spill was 11 Million gallons) (The Ixtoc I spill in 1979 600 miles south of Texas spilled 140 Million gallons.) In the middle of May, Steven Wereley, an associate professor of mechanical engineering at Purdue University, estimated the rate of the oil spill as 56,000 to 84,000 barrels a day. On May 27 the Flow Rate Technical Group (FRTG) (A group of government and academics who are tasked with providing the government with an independent scientific assessment of the scope of the disaster.) put the volume of oil flowing from the blown-out well at 12,000 to 19,000 barrels (500,000 to 800,000 US gallons) per day. On June 10th the FRTG said that as many as 40,000 barrels of oil have been flowing daily. On June 16 the FRTG concluded that the most likely flow rate of oil today is between 35,000 and 60,000 barrels per day. See Largest oil spills. Gulf Oil Data: 3,500 production platforms which pump the oil and gas by pipeline to the shore. 1.7 million barrels (71 million gallons) per day 30% of domestic oil production 11% of domestic oil consumption 
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Apr. 2? Containment efforts.
