This undated image provided by Deepwater Horizon Response Unified Command shows the Deepwater Horizon Blowout Preventer. The manufacturer of a fail-safe device on the oil well that is spewing crude into the Gulf of Mexico has $500 million in liability insurance for legal claims. Cameron International Corp. said Monday, May 3, 2010 in a statement that authorities are still investigating and it has already been named in several lawsuits. (AP Photo/Deepwater Horizon Response Unified Command)
The California Democrat said in a hearing Wednesday that the investigation also discovered that the well had failed a negative pressure test just hours before the April 20 explosion.
He cited BP documents received by the Energy and Commerce Committee that showed there was a breach in the well integrity that allowed methane gas and possibly other hydrocarbons to enter the well.