Memo Suggests Warning Signs Were Ignored Ahead of Rig Explosion

A House panel investigating the Deepwater Horizon oil leak in the Gulf of Mexico says that during the hours that led up to the rig explosion, there were a series of missed and ignored warning signs that signaled significant problems with the well.

The signs were detailed in a memo by Rep. Henry Waxman, D-Calif., chair of the House Committee on Energy and Commerce. The memo is based on two weeks of hearings, testimony and document review by the committee, mainly of executives and records from BP, Transocean, Halliburton, and Cameron.

“Key questions exist about whether proper procedures were followed for critical activities throughout the day,” according to the memo.

The memo notes several red flags throughout the day as engineers attempted to temporarily cap the well. Those red flags included concerns about pipeline pressure readings, fluid flow rates, and the cement work around the pipe.

Five hours before the explosion, according to the memo, there was an “unexpected loss of pressure” in the riser pipe that brings oil from the well to the rig, which should have indicated a possible leak in the blowout preventer device intended to seal the well and stop an oil gusher in case of emergency.

The memo also indicates that in the two hours before the explosion, engineers may have made a “fundamental mistake” in ignoring a pressure reading that should have been an “indicator of a very large abnormality.” Engineers also decided to go ahead with a procedure to remove heavy drilling mud used to keep downward pressure on the oil and to replace it with seawater.

In the hour before the explosion, signs of trouble increased — including sharp increases in pressure and oil flow even though the well’s pumps were shut down.

“The data suggests that the crew may have attempted mechanical interventions at that point to control the pressure, but soon after, the flow out and pressure increased dramatically and the explosion took place,” the memo says.