Argument Aboard Oil Rig, Hours Before Explosion

The site of the Deepwater Horizon oil spill in the Gulf of Mexico is busy with boats cleaning up the spill on the surface and boats and rigs working to collect the leaking oil and shut the leak down on Saturday, May 22, 2010. (AP Photo/The Times-Picayune, Rusty Costanza) MAGS OUT; NO SALES; USA TODAY OUT
AP/Rusty Costanza, Times-Picayune
Eleven hours before the rig on the Deepwater Horizon exploded, causing a massive ecological disaster in the Gulf, there had been an argument over the protective drilling mud that connected the rig to the oil well, the New Orleans Times-Picayune reports.

Details of a disagreement came out on the witness stand at the joint U.S. Coast Guard and Minerals Management Service hearings in Kenner, La. on Wednesday into the deadly explosion aboard the Deepwater Horizon oil rig on April 20 which resulted in the catastrophic oil spill in the Gulf of Mexico.

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"I recall a skirmish between the company man, the OIM (offshore installation manager), the tool-pusher and the driller," said rig worker Doug Brown. "The driller was outlining what would be taking place, whereupon the company man stood up and said, 'No, we'll be having some changes to that.' It had to do with displacing the riser for later on."

Brown went on to say that the driller and the tool pusher reluctantly agreed to the change.

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Capt. Carl Smith, a former Coast Guard captain, told the joint investigative panel that he doesn't know why a rig would displace the protective column of heavy mud with light seawater before closing off a well.

"That's something you learn at well-control school," Smith. "If you're circulating fluid, you need to monitor how much is going in and how much is coming out. If you get more fluid out than in, it's an indicator that something's going on."

It was not unusual for there to be a conflict between the company that's leasing the rig and oilfield and the drilling operators, Smith testified.

He said the "company man" represents a firm that leases the rig and often pays $500,000 a day to drill for the oil, so is concerned about speed and cost.

"That's a natural point of conflict that I've seen," Smith said. "But I have to say, most of them are safety conscious."