Oil Rig Explosion Followed Argument, Warnings

(CBS)  A mechanic's testimony Wednesday before a government panel and internal documents BP provided to Congress help piece together the hours leading up to the explosion that left 11 workers dead and caused the leak spilling millions of gallons of oil into the Gulf of Mexico.

Special Section: Disaster in the Gulf

On April 20, the Deepwater Horizon had finished drilling. Workers were getting ready to seal the well shut until another rig could pump the oil. Eleven hours before the explosion, chief mechanic Douglas Brown says there was tension over how to cap the well between the rig's owner, Transocean, and a BP representative, whom he calls "the company man," CBS News Correspondent Sharyl Attkisson reports.

"The driller was outlining what as going to be taking place, whereupon the company man stood up and said, 'No, we have some changes to that,'" Brown testified during a hearing.

When others disagreed, Brown said "the company man was basically saying, 'Well, this is how it's gonna be.'"

Internal documents BP provided Congress help piece together the most detail yet of events after that contentious meeting.

At 5:05 p.m. Central time - five hours before the explosion - a possible leak in the critical rubber gasket closes tightly around the drill pipe.

Mike Williams, the rig's chief electronics tech, told CBS' "60 Minutes" that chunks of rubber from the gasket had broken loose weeks before, but a supervisor brushed off concerns.

"I thought how can it be not a big deal? There's chunks of our seal is now missing," Williams said.

"60 Minutes" | Blowout: The Deepwater Horizon Disaster

About two hours before the explosion, there's a bad pressure test result, a possible "influx of the well." Pressure builds and there's an indicator that BP investigators now call "a very large abnormality." Yet the rig team moves on. BP says this may have been a "fundamental mistake."

At 51 minutes before the explosion, a bad sign: more fluid flows out of the well than is being pumped in.

At 41 minutes before, the pump is closed for a test, but the well continues to flow. Pressure unexpectedly rises.

At 18 minutes before, data show more abnormal pressures and "mud returns." The pump abruptly shuts down.

The new data from BP suggests the crew may have attempted mechanical fixes at that point to control pressure but in vain. Pressure shot up and the well exploded.

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Oil Rig Explosion Videos from "60 Minutes"

Extra: Mike Williams on Andrea's Rescue
Extra: "I'm Gonna Die Right Here"
Extra: "As I Got To The Next Door, It Exploded"
Extra: "It Was A Ranging Inferno"
Extra: "We Were In Bad Trouble"
Extra: "We're Gonna Burn Up Or We're Gonna Jump"
Extra: "I Must Be Dead"
Extra: Capturing The Disaster
Extra: Warning Signs

[AnnieDanny]

Is the Gulf of Mexico going to be destroyed on account of this? I just took a look at the underwater video and that's scary stuff, what's going on down there. How could anybody "skip" any kind of safety precautions considering what's at stake with oil drilling? I don't feel like buying BP gas these days, that's for sure. I see those BP signs and feel sick about all the damage to seas, lands, fish, fowl, animals and people. This situation is beyond words.

[formrusmcsgt]

Well, well, well...a seal gets torn up and it's "no big deal".

BP will pay tons of cash before it's over with this revelaion....

[jackpenn]

This is so typical of some higher up in management thinking he knows what's best, and it ends up a big mistake. I am faced with the same problem where I work in the chemical industry, when upper management doesn't have a clue on what really goes on in the production areas, because they're never around. When management starts listening to the on the job workers who actually run the operation on a day to day basis, problems like this oil spill would've never happened. How come BP didn't have a "fail safe" precautionary device with a backup, when something this catastophic could happen and did.