BP agreed in 2004 to the installation of a test valve and replacement of another key part on the Deepwater Horizon’s blowout preventer, although it acknowledged that doing so would reduce redundancies and increase risks on the drilling rig.
The agreement was the subject of a letter, obtained by The Washington Post, written by rig owner Transocean and signed by a BP representative.
But BP told members of Congress this month that it did not know about a reconfiguration of the blowout preventer.
Meanwhile, the oil washing into the marshes along the Gulf Coast could also prove impossible to clean up — leaving behind a toxic stew lethal to fish and wildlife, officials said.
Among the drastic and risky tactics under consideration is setting the wetlands on fire or flooding areas in hopes of floating out the oil.