Gulf Tragedy Update

Here is a the best scenario we have to date about exactly what happened.

The deadly blowout of an oil rig in the Gulf of Mexico was triggered by a bubble of methane gas that escaped from the well and shot up the drill column, expanding quickly as it burst through several seals and barriers before exploding, according to interviews with rig workers conducted during BP’s internal investigation.

While the cause of the explosion is still under investigation, the sequence of events described in the interviews provides the most detailed account of the April 20 blast that killed 11 workers and touched off the underwater gusher that has poured more than 3 million gallons of crude into the Gulf.

Portions of the interviews, two written and one taped, were described in detail to an Associated Press reporter by Robert Bea, a University of California Berkeley engineering professor who serves on a National Academy of Engineering panel on oil pipeline safety and worked for BP PLC as a risk assessment consultant during the 1990s. He received them from industry friends seeking his expert opinion.

A group of BP executives were on board the Deepwater Horizon rig celebrating the project’s safety record, according to the transcripts. Meanwhile, far below, the rig was being converted from an exploration well to a production well.

Based on the interviews, Bea believes that the workers set and then tested a cement seal at the bottom of the well. Then they reduced the pressure in the drill column and attempted to set a second seal below the sea floor. A chemical reaction caused by the setting cement created heat and a gas bubble which destroyed the seal.

Deep beneath the seafloor, methane is in a slushy, crystalline form. Deep sea oil drillers often encounter pockets of methane crystals as they dig into the earth.

As the bubble rose up the drill column from the high-pressure environs of the deep to the less pressurized shallows, it intensified and grew, breaking through various safety barriers, Bea said.

"A small bubble becomes a really big bubble," Bea said. "So the expanding bubble becomes like a cannon shooting the gas into your face."

Up on the rig, the first thing workers noticed was the sea water in the drill column suddenly shooting back at them, rocketing 240 feet in the air, he said. Then, gas surfaced. Then oil.

"What we had learned when I worked as a drill rig laborer was swoosh, boom, run," Bea said. "The swoosh is the gas, boom is the explosion and run is what you better be doing."

The gas flooded into an adjoining room with exposed ignition sources, he said.

"That’s where the first explosion happened," said Bea, who worked for Shell Oil in the 1960s during the last big northern Gulf of Mexico oil well blowout. "The mud room was next to the quarters where the party was. Then there was a series of explosions that subsequently ignited the oil that was coming from below."

According to one interview transcript, a gas cloud covered the rig, causing giant engines on the drill floor to run too fast and explode. The engines blew off the rig and set "everything on fire," the account said. Another explosion below blew more equipment overboard.

BP spokesman John Curry would not comment Friday night on whether methane gas or the series of events described in the internal documents caused the accident.

"Clearly, what happened on the Deepwater Horizon was a tragic accident," said Curry, who is based at an oil spill command center in Robert, La. "We anticipate all the facts will come out in a full investigation."

The BP executives were injured but survived, according to one account. Nine rig crew on the rig floor and two engineers died… [emphasis added]

Inserted from <Raw Story>

The irony of the BP executives’ presence and their survival when workers died is inescapable.  This may also explain the GOP leaders’ insistence that we continue to expand offshore drilling.  They are so used to spewing methane themselves that they don’t see how dangerous it is.

Speaking of methane, it’s still causing problems.  In yesterday’s open thread, I reported that BP had placed the dome over the biggest leak.  They had to move it.  I thank my friend Diane for the tip to this article.

London-based BP Plc’s plan to lower a giant containment dome to trap oil from a blown-out Gulf of Mexico oil well on the sea floor hit a technical obstacle on Saturday in the form of methane hydrates, or flammable ice, a BP executive said on Saturday.

BP officials are scrambling for a solution after methane hydrates stopped up the 98-ton containment dome as they were maneuvering it into place, Doug Suttles, BP’s chief operating officer, told reporters at a briefing in Robert.

"As we were placing the dome over the leak source a large volume of hydrates formed inside the top of the dome, requiring us to move the dome to the side of the leak point," Suttles said. "I wouldn’t say it’s failed yet."

The four-story structure, BP’s only short-term hope of controlling the leak, is supposed to redirect the unchecked flow of crude from nearly one mile below the water and, once connected, pump it to a surface tanker.

If the dome plan fails, BP faces the prospect of drilling a relief well to cut off the leaky oil well, which could take two to three months. A giant oil slick from the gush of oil threatens to create an environmental disaster for four Gulf Coast states.

Methane hydrates — a slush of frozen hydrocarbons and water that form in the deep, cold conditions at the leak site — began clogging up the opening in the dome, forcing them to set the structure aside, Suttles said.

The dome is now resting on the ocean floor about 200 meters (660 ft) from the leak source, and it could take 48 hours or more to find a workaround, Suttles said.

Those could include using hot water to heat up the hydrates at the ocean floor, or using hydrocarbons like methanol to thin them out, Suttles said.

Suttles said BP is mulling two other short-term fixes, including installing a new blow-out preventer on the leak site and trying to clog up the existing failed blow-out preventer with an injection of rubber and other solids, known as a "junk shot."

Hydrates are highly flammable and present a danger to BP workers on ships above the leak. If they dethaw in an uncontrolled manner, they could send a flood of natural gas to the top of the ocean surface and potentially ignite.

Ironically, methane hydrates are a promising future energy source in themselves, but researchers are still searching for ways to safely harness them… [emphasis added]

Inserted from <The Bay Ledger>

There’s one part of this story that has not gotten adequate coverage.  Since I’m telling this from memory, I’m including no dates, but the sequence of events is correct.  Halliburton was a relatively small company, when Dick “ChickenHawk” Cheney gave them their first big government contract, when he was at Defense during the GHW Bush administration.  When Bill Clinton defeated GHW, Cheney lost his job at Defense, and Halliburton made him CEO.  He used his Defense Dept. contacts to help Halliburton get more federal contracts.  Cheney was elected granted the Vice Presidency by the GOP extremists at SCOTUS.  With his pockets stuffed with Halliburton stock options, Cheney enabled them to receive billions in no bid contracts in the Bush/GOP War for Oil and Conquest of Iraq.

When Cheney took office, the Materials Management Service (MMS) had written and was on the verge if implementing a regulation that would require offshore oil platforms to use emergency shut off valves that are required virtually everywhere in the world except here.  Cheney gutted the MMS, firing the competent people there and replacing them with his cronies.  He held secret meetings with energy executives and allowed them to write this nation’s energy policy.  The regulation was never adopted, BP got to save $500,000 by using blow-out preventers with a proven track record of failure, and Halliburton, despite their shoddy work record, mysteriously took over the hazardous job of cementing oil wells.

BP’s top executives are Brits.  That makes Dick Cheney the single American most responsible for this tragedy.  This is how the GOP manages business, and is why they must never again be allowed back in power.