Published: May 12, 2010 4:43 PM EDT

Washington, D.C.-Lawmakers looking into the explosion and oil spill in the Gulf of Mexico say a crucial piece of safety equipment had a leak.

Henry Waxman, who chairs the House Energy and Commerce committee, says the maker of the blowout preventer told lawmakers the device had a leak.

The California Democrat believes a series of equipment and operational failures led to the explosion.

"Transocean, one of the world's largest operator of drilling rigs, says it has no reason to believe that the rig's failsafe device, called a blow out preventer, was not fully operational, but we have learned from Cameron, the manufacturer of the blow out preventer, that the device had a leak in a crucial hydraulic system and a defectively configured ram."

"The more I learn about this accident, the more concerned I become. The catastrophe appears to have been caused by a calamitous series of equipment and operational failures If the largest oil and oil service companies in the world had been more careful, eleven lives might have been saved and our coastlines protected."

Waxman also says his committee's investigation revealed the well failed a negative pressure test just hours before the 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.