.Mystery over crews failure to react
By Stephanie Kirchgaessner in Washington
Published: May 27 2010 19:00 | Last updated: May 27 2010 19:00
The first bang knocked out the power. It also killed lines of communication between the Deepwater Horizon rig, 67 miles off the coast of Louisiana, and BPs headquarters on Houston. Then, as the alarm bells were ringing, there was another bang, and all hell broke loose.
Five weeks after the April 20 explosion that killed 11 men and sent hundreds of thousands of barrels of oil streaming into the Gulf of Mexico, congressional and internal corporate investigations at BP say one thing is certain: multiple failures led to the disaster, including human error.
EDITORS CHOICE
Obama unveils offshore drilling rules - May-27.Energy source: Live top kill updates - May-27.US oil regulator resigns - May-27.Gulf of Mexico faces bad storm season - May-27.In depth: BP oil spill - May-26.BP awaits top kill effort - May-27..At a briefing with reporters this week, BP investigators claim they do not understand why crew members missed or perhaps did not correctly interpret several red flags.
They say they believe it was not until 51 minutes before the explosion that the crew realised something had gone terribly wrong inside the well. Though there are no eyewitness accounts, they believe members of the crew tried in vain to intervene in the final 18 minutes, trying twice to close the valves on the blow-out preventer near the sea floor that were supposed to prevent an explosion.
In a timeline given to congressional investigators, BP says a riser pipe was showing a loss of fluid up to five hours before the blast, an indicator of leaks inside the well.
According to BP, rig operators missed signs that more fluid was flowing out of the well than was being pumped inside, although the company says it does not know whether this anomaly was being observed by the crew.
The British energy group says it knows for certain there was a failure in the cementing of the well, a process meant to stop any gas entering the main well pipe. The cementing was handled by Halliburton, the oil services company, which says it followed BPs instructions. Halliburton did not respond to requests for comment. BP says it believes the cement may have been contaminated.
However, congressional investigators are studying why BP did not perform full tests to ensure that the cement job had been done adequately. Workers for Schlumberger, who were meant to test the integrity of the cement, left the rig on the morning of the blast.
According to BPs account, the rig crew did not realise that pressure was building up inside the well, even though a pressure reading taken hours before the explosion clearly indicated something was wrong. The pressure reading, which BP says was observed by more than one person, would have shown that pressure inside the main well and the kill line were equal if everything was working properly. Instead, the readings were uneven.
BP says it does not know why the crew did not react to the reading. But BPs initial findings are far from complete and have been challenged by eyewitnesses and other companies.
Questions about BPs version of events were heightened yesterday when a BP employee aboard the Deepwater Horizon rig at the time of the explosion was expected to decline to testify at a hearing in Louisiana, citing his fifth amendment rights against self-incrimination.
At a hearing this week in Louisiana, Douglas Brown, chief mechanic of Transocean, which owned the Deepwater Horizon rig, testified that a top BP employee had a skirmish with top Transocean officials on the day of the blast. The fight was allegedly about a decision to remove heavy drilling mud from the drill pipe and replace it with water.
BP has said that the decision to push ahead with the procedure, despite the questionable pressure reading, was probably a fundamental mistake.
Mr Brown said he overheard Jimmy Harrell, Transoceans top rig manager, say: Guess thats what we have those pinchers for as he left the meeting, having reluctantly agreed to follow BP instructions and continue pumping water into the pipe.
Mr Brown said he believed Mr Harrell was referring to the shear rams on the blow-out preventer, which were designed to cut off the flow of oil and gas in an emergency.
The Transocean mechanic said the first blast threw him against the control panel he was standing in front of. It was completely chaotic and nobody was really paying attention in my opinion. They were more concerned about just getting off the rig escaping, he said
