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

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 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.