BP Oil Spill: Company Report Probes Cause of Gulf of Mexico Disaster

Oil giant's internal report points fingers at Transocean and Halliburton.

Sept. 8, 2010— -- In its first report on the disaster at the Deepwater Horizon rig that killed 11 crew members and unleashed the worst oil spill in the nation's history, BP took some of the blame for the disaster in the Gulf of Mexico but was quick to point the finger at its partners.

The 193-page internal report is the product of a four-month investigation led by Mark Bly, BP's head of safety and operations. The company said that it conducted the investigation independently, relying on a team of dozens of specialists who began to probe the disaster almost immediately after the explosion.

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"The team did not identify any single action or inaction that caused this accident," the authors wrote on page 11. "Rather, a complex and interlinked series of mechanical failures, human judgments, engineering design, operational implementation ... came together to allow the initiation and escalation of the accident. Multiple companies, work teams and circumstances were involved over time."

The report outlined eight key findings that led to the explosion and leak, including a flawed cement job below the ocean floor, the failure of employees to correctly interpret the results of a "negative-pressure test" and a malfunctioning blowout preventer that that did not do its job to seal off the leaking well.

BP Acknowledges Employee Errors, but Others Also Responsible

BP acknowledged its own employees' mistakes in interpreting the results of a negative-pressure test, but it also blamed the Transocean rig crew for the error. In the report's other key findings, non-BP contractors bore the brunt of the blame.

In a statement released by BP, outgoing CEO Tony Hayward said that BP was to blame, but he also pointed to the company's partners, Halliburton and Transocean.

"Based on the report, it would appear unlikely that the well design contributed to the incident," Hayward said in the statement.

Not everyone agreed with Hayward's assessment, including Transocean, which has already called the BP report self-serving and blamed "BP's fatally flawed well design" and cost-savings measures for the disaster.

Report an Indicator of BP's Legal Strategy?

Critics said that, more than anything else, the report offered a glimpse of BP's coming legal strategy, spreading blame to avoid serious financial penalties. The company's stock went up today on news of the report's release.

One outspoken critic of BP, Rep. Edward Markey, D-Mass., was quick to express his disappointment with the report's findings.

"This report is not BP's mea culpa," Markey told The Associated Press. "Of their own eight key findings, they only explicitly take responsibility for half of one. BP is happy to slice up the blame, as long as they get the smallest piece."

Several Investigations Now Examining Spill

Multiple other government agencies, organizations and companies are in the midst of investigating the spill. The Justice Department, the Bureau of Ocean Energy and Management and private companies such as Transocean have all launched their own probes.

"[BP's report] is not an end-all-be-all ... about why it happened and what needs to happen in the future," Adm. Thad Allen said today during a conference call with reporters as he described ongoing efforts to finish the bottom kill at the site of the well.

Indeed, BP's report was issued before investigators could look extensively at a key piece of physical evidence, the damaged blowout preventer. The 300-ton device was raised from the ocean floor last week to be moved to a NASA facility in Louisiana for examination.

The Associated Press and ABC News' George Sanchez contributed to this story.

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