The Transocean corporation's assertions were filed Friday in federal court in New Orleans, where a civil began last week to determine percentages of blame and how much BP, Transocean and others will pay for the April 2010 catastrophe that killed 11 workers and sent millions of gallons of oil spewing into the Gulf for 87 days.
"In short, beginning in late April and continuing throughout May 2010, BP repeatedly represented to source control decision-makers, Congress, the press and the public that 5,000 bpd was its best estimate of the flow rate," the Transocean filing said. "It withheld numerous documents, analysis and estimates that would have allowed those outside BP to realize that BP's flow rate claims were misleading and fraudulent."
Transocean, which leased the Deepwater Horizon rig to BP, says the leak could have been stopped two months earlier. The motion filed Friday seeks to limit or eliminate Transocean's liability for damages, and outlines a case for collecting damages from BP itself.
Transocean's filing says federal officials attempted a method of stopping the flow that was destined to fail because oil was spewing at a greater rate than BP was publicly acknowledging. That method, known as "top kill," involved plugging the well by injecting drilling mud and solid material.
The attempt failed. Transocean, citing various documents and evidence including BP's recent guilty plea to criminal charges, said BP was well aware of estimates that much more oil was flowing, varying from 70,000 to 100,000 barrels per day.
Ultimately, a device known as a "capping stack" stopped the flow.
Transocean said that, but for BP's actions, the oil flow could have been stopped sometime in May. BP has already pleaded guilty to manslaughter and other criminal charges and has racked up more than $24 billion in spill-related expenses, including $4 billion in criminal penalties.
In the trial that began Monday, Gulf Coast states and individuals and businesses hope to convince a federal judge that the company and its partners in the drilling project are liable for much more in civil damages under the Clean Water Act and other environmental regulations. BP could be on the hook for nearly $18 billion if a judge finds that it acted with "gross negligence."
The trial resumes Monday and is expected to last for months.