A BP (British Petroleum) executive said Wednesday that in the hours after the Gulf of Mexico well explosion, critical time was wasted trying to learn what changes had been made to a device designed to prevent oil from leaking from the blown-out Macondo well. Harry Thierens, BP's vice president for drilling, told a panel of federal investigators in Houston, Texas that he was highly involved in trying to shut down the well after the April 20 explosion. As attempts were being made to shut the well with the blowout preventer, it became clear that rig-owner Transocean had made changes to the device's locking mechanism, Thierens said, adding that it took between 12 and 24 hours to obtain the correct drawings of the changes. Ultimately, the blowout preventer failed, creating the worst offshore oil spill in U.S. history. Since then, BP, Transocean, and oil-services firm Halliburton have blamed each other for alleged mistakes that led to the environmental disaster.
