BP Investigation Says Engineers Misread Deepwater Horizon Data

BP's (BP) investigation into the Deepwater Horizon rig oil disaster accepts that the company is at least partly responsible for the disaster, with employees misinterpreting data that suggested a blowout was imminent, Bloomberg News said.

BP managers on the rig misinterpreted a test of Macondo well's stability, Bloomberg News said. Workers then began replacing drilling fluid in the well with seawater, which led to natural gas shooting up the pipe to the rig, where it exploded.

The disaster killed 11 people and the ruptured Macondo well spewed out more than 4 million barrels of crude oil into the Gulf of Mexico.

A federal investigation has asked why BP engineer John Guide ignored warnings of a potential blowout from contractor Halliburton Co. (HAL), and why managers didn't test for flaws in cement that was meant to prevent natural gas seeping up to the rig.