BP, running weeks behind schedule and tens of millions of dollars over budget in trying to complete its troubled Macondo well in the Gulf of Mexico, took many shortcuts that contributed to the disastrous blowout and oil spill there last year, federal investigators concluded in a report released on Wednesday.
The central cause of the explosion aboard the Deepwater Horizon drilling rig was a failure of the cement at the base of the 18,000-foot-deep well that was supposed to contain oil and gas within the well bore. That led to a cascade of human and mechanical errors that allowed natural gas under tremendous pressure to shoot onto the drilling platform, causing an explosion and fire that killed 11 of the 115 crew members and caused an oil spill that took 87 days to get under control.
The two-part report, compiled by a joint task force of the Bureau of Ocean Energy Management, Regulation and Enforcement and the Coast Guard and covering more than 500 pages, is the most comprehensive to date on the April 2010 disaster. Its findings largely mirror those of other investigations, including the inquiry by a commission named by President Obama to determine the causes of the calamity. That panel issued its findings in January.
“The loss of life at the Macondo site on April 20, 2010, and the subsequent pollution of the Gulf of Mexico through the summer of 2010 were the result of poor risk management, last-minute changes to plans, failure to observe and respond to critical indicators, inadequate well control response and insufficient emergency bridge response training by companies and individuals responsible for drilling at the Macondo well and for the operation of the Deepwater Horizon,” the latest report said.
The report concluded that BP, as the well’s owner, was ultimately responsible for the accident. But it also said that BP’s chief contractors, Transocean, which owned the mobile drilling rig, and Halliburton, which was responsible for the cementing operations, shared the blame for many of the fatal mistakes.
The study goes further than previous reports, citing seven violations of federal regulations as factors. Among them were violations of laws that required BP and its contractors to operate in a safe manner, to take measures to contain oil and gas for the protection of health and the environment, to conduct reliable tests of well pressures and to notify federal regulators of changes in drilling plans.
The Justice Department is conducting a criminal investigation that could bring indictments and heavy fines.
David M. Uhlmann, a professor at the University of Michigan Law School and former chief of the Justice Department’s environmental crimes section, said the Justice Department almost certainly reviewed the findings of the study before it was released.
“Today’s report increases the likelihood that BP, Transocean and Halliburton will face criminal charges for their roles in causing the gulf oil spill,” Mr. Uhlmann said in an e-mail. “The Justice Department may have outside experts for both its criminal and civil cases, and it could develop additional information about the causes of the spill in those investigations, but it will be hard for the Department to distance itself from the findings of the Coast Guard and Boemre.”
The well blowout unleashed a spill of nearly five million barrels of oil, fouling the gulf and hundreds of miles of beaches, marshes and fish habitats and causing billions of dollars in damage.
The three companies have pointed fingers at one another and are engaged in multibillion-dollar litigation to try to spread the enormous costs of the accident. Families of crew members are suing the companies in federal court, seeking compensation and damages.
BP said in a statement that it had long acknowledged its role in the accident and had urged its drilling partners to accept their share of the blame.
“BP agrees with the report’s core conclusion — consistent with every other official investigation — that the Deepwater Horizon accident was the result of multiple causes, involving multiple parties, including Transocean and Halliburton,” the company said. It added that it had taken steps to improve its safety practices and strengthen oversight of its contractors.
Lou Colasuonno, a Transocean spokesman, said that the report identified the cement failure as the primary cause of the accident and defended the actions of Transocean crew members.
“We take strong exception to criticisms of the Deepwater Horizon drill crew, nine of whom perished fighting to save their fellow crew members and the rig, for the actions they took in the face of such an unprecedented emergency,” he said in a statement.
A Halliburton spokeswoman said that BP was to blame for poor well design and that at least some of the cement set by Halliburton did not fail. The company absolved itself of any blame. “Every contributing cause where Halliburton is named, the operational responsibility lies solely with BP,” the statement said.