Thursday, May 6, 2010

Deepwater Horizon Blowout - The True Story

Have you heard your conservative Republican friends and neighbors wonder out loud if liberal environmentalists plotted with Obama's government to blow up the Deepwater Horizon oil drilling platform in the Gulf of Mexico to advance their radical environmentalist anti-drilling political agenda? "Think Progress reports on the latest right-wing conspiracy to shift blame from Big Oil to liberals in general and Obama in particular:
As the scale of the disaster caused by the explosion at an oil rig off the coast of Louisiana became more apparent last week, right-wing radio talker Rush Limbaugh unleashed a conspiracy theory suggesting that someone intentionally blew up the rig in order to “head off more oil drilling” ... "So, since they’re sending SWAT teams down there, folks, since they’re sending SWAT teams to inspect the other rigs, what better way to head off more oil drilling, nuclear plants, than by blowing up a rig? I’m just noting the timing here," said Rush Limbaugh on his radio program
Picking up on Limbaugh’s and oil spill truther's liberal conspiracy theory on fringe websites the Fox News conservative megaphone is also pushing the conspiracy theory that hardcore liberal environmentalist plotted with Obama's government to blow up the rig to advance their environmentalist anti-drilling political agenda. On Fox and Friends, former Bush Press Secretary Dana Perino said she was “not trying to introduce a conspiracy theory, but was this deliberate?” ... “If there was sabotage involved,” wondered Perino. Later in the same day's show, host Steve Doocy asked Fox Business’ Eric Bolling to respond to people who have suggested that “there’s a possibility this could be sabotage.” Citing Perino, Bolling engaged in conspiracy speculation:
BOLLING: The question is did they let this thing leak? Did they let it leak a little bit and say, “boy I don’t know.” I mean, the conspiracy theorists would say, maybe they let it leak for a while and then they address the issue.
Another Fox program host Gretchen Carlson called Bolling’s speculation “a humongous accusation.” He agreed, adding, “but if they’re going to try to pull drilling, that may be the way to do it.” Watch video left:

BP America Inc. President Lamar McKay blamed the disaster on [the well blowout preventer on the gulf sea-bed in 5000 feet of water, that he called] “a failed piece of equipment,” in an interview with ABC News yesterday, adding that they “don’t know why it failed yet.” The blowout preventer is a 500,000 pound massive failsafe hydraulic valve intended to cut and seal the well pipe in case of a catastrophic blowout. The disaster occurred as Halliburton was cementing, or sealing, the well bore so that the drilling platform could be moved to a new drilling location.
An offshore blowout is when seawater and drilling mud containing gas from the well spew up from the well pipe onto the drilling rig floor; A blowout preventer (BOP) is a large valve that can seal off the wellhead, when the drilling crew loses control of drilling mud pressure and formation pressure forces oil or gas up to the drilling platform. By closing this valve (usually operated remotely via hydraulic actuators), the drilling crew can prevent a blowout of the well bore.

Oil industry expert talks to
Fox News America's Newsroom
Oil wells do blowout and blowout preventers do fail -- absent any liberal conspiracy to blow up off shore rigs. In fact, Deepwater Horizon blowout is the second such deep water blowout in less than a year.

Just eight months ago, the BOP failed on a deep-water well in the Timor Sea, north-west of Australia. After five attempts and 10 weeks a relief well was drilled and the blowout flow, which was much smaller than Deepwater Horizon blowout flow, was stemmed.

An analysis of incidents in the Gulf of Mexico by the Texas A&M researchers showed that offshore blowouts have continued at "a fairly regular rate since 1960 despite the use of BOPs. A 2007 paper from the Minerals Management Service said between 1992 and 2006 there have been 39 actual blowouts.

Drilling for oil at depths greater than 3000 feet of water was rare a decade ago, but the profit to be made from deep water wells has made exploration economically feasible. Such wells are now common off the coasts of Brazil, Angola and Nigeria as well as in the Gulf of Mexico.

The Deepwater Horizon well head is more than a mile under water on the gulf sea-floor. A report by engineering consulting firm URS Corp. in 2002 concluded that "Technologies used in shallow waters are not adequate for water depths over 3000 feet. Engineering requirements and operational certification procedures for equipment used for deep water drilling are not well understood or tested.

Video of a blowout preventer being landed on a sea-floor well head and control cables connected by ROV.
In 2005 petroleum engineering researchers from Texas A&M University suggested that drilling in the "dangerous and unknown" ultra-deep environment required new blowout control measures: "While drilling as a whole may be advancing to keep up with these environments, some parts lag behind. An area that has seen this stagnation and resulting call for change has been blowout control."

A 2003 report co-authored by the then-director of technology development for Transocean, the company that owned the Deepwater Horizon rig that caught fire on April 20 and sank two days later, delivered at an industry conference warned that the industry wasn't taking time to find and fix underlying problems that commonly plagued blowout preventers. "Floating drilling rig downtime due to poor BOP (blowout preventer) reliability is a common and very costly issue confronting all offshore drilling contractors," the report said.

A 2008 report authored by officials of BP America and Transocean and published by the Society of Petroleum Engineers raised new questions about whether the blowout preventers on the deep water wells, like that the Deepwater Horizon was drilling, could face a new problem.

A 1999 report commissioned by the federal agency that oversees offshore drilling suggests failures of underwater blowout preventers designed to stop oil spills like the massive one threatening the Gulf Coast were far from rare. Citing a Minerals Management Service report, Sen. Maria Cantwell, D-Wash., said there were 117 failures of blowout preventers during a two-year period in the late 1990s on the outer continental shelf of the United States. Sen. Maria Cantwell is the chairwoman of the Senate Commerce Committee's oceans, atmosphere, fisheries and Coast Guard subcommittee.

The unclassified version of the 1990 report said the failures involved 83 wells drilled by 26 rigs in depths from 1,300 feet to 6,560 feet. A similar report released by the agency in 1997 found that between 1992 and 1996 there were 138 failures of blowout preventers on underwater wells being drilled off Brazil, Norway, Italy and Albania. No additional studies were commissioned by the Bush administration during his term from January 2001 to January 2009.

Horizon.jpgThe Deepwater Horizon was a large semi-submersible (meaning that it floats on large pontoons that actually float below the surface) and contains drilling, completion, cementing, and production facilities all on one vessel.

Transocean Horizon LocatorMap.jpgDeepwater Horizon was drilling an exploration well in a deep-water area known as Mississippi Canyon off of the coast of Louisiana.

Once a exploration well is drilled and a producing oil field discovery is confirmed it is sealed and multiple production wells are drilled. Initial reports of the accident said that the Deepwater Horizon platform drilling crew had set a cement plug deep in the well, to seal the exploration bore hole, and were displacing the weighted drilling mud in the riser pipe from the ocean floor to the drilling platform with sea water to recover the drilling mud.
Weighted drilling mud fills the pipe to hold back the oil and gas formation pressure while the well is being drilled. Properly weighted drilling mud prevents a blowout. The riser was 5,000 feet of 21" diameter pipe, some buoyant, some negatively buoyant.
As soon as the weighted drilling mud was recovered the platform was to be moved to another location to drill a production well in the newly confirmed oil field.

Initial speculation was that one or all of the cement plugs failed, and as the heavier drilling mud was displaced by lighter sea water, the reduced hydrostatic head pressure allowed the formation pressure to blowout of the well riser pipe.

Initial consensus was that the BOP, 5,000 feet below sea level, was irreparably damaged when the drilling platform and 5,000 feet of riser pipe collapsed to the sea floor. ROVs worked directly on the BOP over several days, doing everything that should have activated it but all efforts failed to stop the flow of oil and gas.

---------------- Updated May 12, 2010 ----------------

What really caused the blowout? An account given by two workers on the drilling rig and corroborated to some extent by Transocean, owner of the Deepwater drilling platform claims that BP, owner of the well, made a key decision to reverse the order of cementing steps used to seal the well. After, cementing the casing, filling in the area between the pipe and the walls of the well, it is standard procedure to pour wet cement down the inside of the drill pipe, which then sinks thousands of feet down through the drilling mud before the cement hardens into a plug. Then the standard procedure is to wait for the cement plug to harden for a period of six hours before the drilling mud is removed. The account given by the two rig workers says that the drilling mud was removed before the cement was poured down the riser pipe.
Weighted drilling mud fills the pipe to hold back the oil and gas formation pressure while the well is being drilled. Properly weighted drilling mud prevents a blowout during drilling. As the heavy drilling mud was displaced by lighter sea water, without the cement plug in place, the reduced pressure inside the well riser pipe allowed the formation pressure to blowout of the pipe.
According to account, BP asked for and receive permission from the federal Minerals Management Service to displace the mud before the final plugging operation had begun. [WSJ Online]

Why didn't the blowout preventer work after the blowout occured? The blowout preventer had a dead battery in its control pod, leaks in its hydraulic system that provides emergency power to the "variable bore ram" device that was supposed to close the flow of oil, a ram cutting tool that wasn’t strong enough to shear through joints that made up 10 percent of the drill pipe, all of which really made no difference because the blowout preventer had been modified so that one of its "variable bore ram" drivers could be used for routine testing and was no longer designed to activate in an emergency. That’s the story told in the WashPost coverage on the devastating opening statement in a hearing of the House Energy and Commerce Committee.

Rep. Henry Waxman says that his House Committee's investigation into the Gulf oil spill reveals that the blowout preventer had a leak in a crucial hydraulic system before the blowout. Without hydraulic pressure the blowout preventer's "variable bore ram," intended to close tight around the pipe and seal it, cam not activate. And at a hearing in Louisiana on Tuesday, the government engineer who gave oil giant BP the final approval to drill admitted that he never asked for proof that the blowout preventer worked. [Huffington Post]

In the days after the blowout BP engineers tried to activate the blowout preventer, but failed because the device had been greatly modified and the diagrams BP got from the equipment's owner didn't match the device's new configuration, congressional investigators said Wednesday. BP engineers wasted many hours before figuring this out. Who ordered the alterations in the blowout preventer? Transocean, the owner of the blowout preventer and of the sunken Deepwater Horizon rig, said any alterations would have come at BP's instigation; BP, which owns the well and hired Transocean to drill it, said it had never sought the changes.

Testimony given before the House Energy and Commerce Committee's Subcommittee on Oversight and Investigations, said alterations to the blowout preventer prevented the massive "variable bore ram" from activating. This ram is intended to cut the pipe and seal it. The alteration had connected a useless test ram - not the variable bore ram - to the socket that was supposed to activate the variable bore ram. [Kansas City Star, a McClatchy Newspaper]


Witnesses describe Deepwater Horizon rig blowout -- Video of disaster
It was a calm night, so when methane gas hit surface, being heavier than air, it settled around the drilling platform deck. The gas grew so dense on deck that it began to invade compartments as the blowout strengthened.

As the electric generator engines that run the rig began to breath in the dense gas/air mix, the engines ran away uncontrollably and exploded. The generator explosions ignited the dense cloud of well gas on deck, which in turn ignited the blowout flow from the riser pipe.

Similar explosions happened in the mud pump room, destroying inner walls, which, according to the reported accounts, were unfortunately adjacent to the living quarters. In a strange twist of fate, the off-shift crew was reportedly having a party in the living quarters, celebrating 7 years of accident free performance. It is reported there were 7 BP executives on board the the drilling platform visiting on the rig for the celebration at the time of the blowout.
Houston Chronicle:

More on this Story

Before the blowout, the rig's crew had been replacing heavy and valuable drilling mud with lighter salt sea­water in the top section of pipe known as the riser . Minutes before the Deepwater Horizon exploded in fire, workers on the deck heard a thump, then a hissing sound [as the well began to blowout.] Gas alarms sounded and the rig shook.

Seawater and [drilling] mud containing gas from the well spewed up through the crown of the derrick and rained down on the drilling floor; fumes reportedly moved into the “safe zones” where the electric generators are located. The generators raced out of control as they sucked gas into the air intakes.

When the electric power surged, light bulbs exploded, computers, control systems and other electric systems were destroyed, leaving the rig in darkness except for the light from fires and explosions that ripped apart walls, according to accounts derived from interviews with attorneys representing survivors, missing rig workers and their families, as well as experts in the field of offshore drilling operations.

Kevin Eugene, a steward on the rig, said he was in his bunk watching TV about 10 p.m. when a “big old loud boom” and an alarm went off “almost simultaneously.”

The lights went out. The platform began shaking.

“I thought the place was falling in the ocean, that the whole rig was collapsing,” said the father of four from Slidell, La.

Ceiling tiles, dust and debris rained down from overhead. Clad only in his pajama pants and undershirt, he scrambled down a hallway toward an exit to a stairwell that would lead to a lifeboat up on deck. He heard more explosions, but can't remember how many.

When he got onto the deck, he felt a blast of heat and saw flames about 200 yards away.

“I mean it was the hugest, biggest fire I've ever seen,” Eugene said. “It was just a big old ball of fire up there on the derrick. The whole derrick was on fire. The fire was shooting from out the well over there that the derrick was connected to and you could hear the gas gushing out.”

The deck was covered with oily mud.


When the alarms go off “you shut it down,” said Daniel Becnel, an attorney from Reserve, La., who has filed lawsuits on behalf of fishermen, oystermen and other Louisiana residents claiming damages from the spill. “They've got panic switches all over the place.”

Those switches are supposed to activate a blowout preventer on the ocean floor, a huge and complex tower of valves and pipe crimpers designed to shut down a well in an emergency. It didn't work.

Although it had been tested beforehand, BP now says robot submarines have discovered at least one problem with the blowout preventer, though it is unclear whether it caused the malfunction.

“We have found that there are some leaks on the hydraulic controls,” said Bob Fryar, senior vice president of BP's exploration and production operations in Angola, in southwestern Africa.
There is much more. The Houston Chronicle story also discusses the issues around the cementing of the well and how that can lead to blowouts sometimes.

The Wall Street Journal has reported that, after review of satellite imagery and calculations made by experts, the BP Mississippi Canyon Block 252 well may actually be flowing at a much higher rate that the unified command is admitting. According the the report, Ian MacDonald, professor of oceanography at Florida State University who specializes in tracking ocean oil seeps from satellite imagery, estimates the daily rate to be 25,000 barrels of oil per day. He says he has shared his data with NOAA scientists, who didn't dispute his findings.

Another scientist, John Amos, a geologist who has worked as an industry consultant tracking oil spills using satellite imagery, is the one who presented data to NOAA last week, which then raised its estimates from 1,000 barrels a day to 5,000. Amos says the 5,000 barrel estimate is at the "extremely low end" of their estimates. He says the more realistic number is 20,000 barrels per day. If these numbers are true, and it does take 90 days to get the relief well drilled, the oil spill will be 8 or 9 times larger than the Exxon Valdez.

The flowing wellhead pressure may be as high as 10,000 PSI and that, even if the BOP could be closed now, could very well be leaking in the locking mechanism below the stack. Leaks always get worse, not better, as anyone knows who's been annoyed by a dripping kitchen faucet. The only problem here is that this faucet is "dripping" at upwards of 25,000 barrels per day. One industry source, who has knowledge of the operations, said, "[the BOP] isn't closed and In my professional opinion, its not going to close..."

The well has now been flowing uncontrolled for 13 days. These units are designed to slam shut, not be flowed through, at least at these high rates and pressures. Erosion of the ram faces and the bore is now likely severe, further reducing its chances of ever actually shutting the well in and sealing.

Preparations are now being made to cut the riser above the BOP in preparation of installing a containment structure to capture the flow of oil. Essentially, it is a large box structure that is lowered over the source of the leak and connected by a riser to the surface. Oil will then flow up the riser to a ship that will process and collect the oil. It is believed that, if successful, this structure could capture up to 85% of the produced oil. This is a technique that has been used successfully in shallow water, but never this deep. It appears that the containment structure is the only chance BP has of slowing the growth of the spill, at least until they get the well killed by a relief well, or if well bore damage slows the flow by itself.

If the flow of oil can not be stopped soon, experts are worried that the Gulf Loop Current could pick up the slick and carry it toward Florida, through the keys, around the Florida panhandle. At that point the slick will be picked up by the enter the Gulf Stream and move up the eastern seaboard.

The Loop Current begins in the Caribbean and travels clockwise up to the Gulf Stream, which runs along the eastern seaboard of the US and into Canada. But if this oil gets picked up by the Loop Current and carried into the Gulf Streem, the scope of the disaster could broaden, affecting the eastern seaboard as far north as Cape Hatteras in North Carolina.

"If oil is swept up into the Loop Current--which moves at about 3.3 to 6.5 feet (one to two meters) a second--there's essentially no way to stop it," Tony Sturges, professor emeritus in oceanography at Florida State University, told National Geographic. "Once [oil] gets into the loop current, you can bet the farm it will go around to the south" of the Florida Peninsula and into the Gulf Stream." Florida should be bracing for the worst, he added. The noxious oil could get pulled into estuaries, harbors and coastal waterways, affecting nurseries for valuable fisheries.


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