JOIN USThe final joint report by the Coast Guard and the Bureau of Ocean Energy Management, Regulation and Enforcement cited as the main cause of the April 20, 2010, disaster "BP's cost- or time-saving decisions without considering contingencies and mitigation".
According to the report, the explosion that killed 11 people and spilled almost 5 million barrels of oil into the ocean was 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" rig.
The oil industry had been anxiously awaiting the report due to its potential impact on deep-water drilling permits.
In January, a commission named by President Barack Obama to probe the disaster had divided the blame between BP and subcontractors Halliburton and Switzerland-based Transocean.
But the Coast Guard/BOEMRE report, while not absolving the contractors, assigns the biggest share of the blame to the British energy giant.
Many of BP's decisions, including neglecting to test the stability of the cement used to seal the well, were "in direct contradiction" to the federally approved, risk-minimizing operating plan.
BP should have taken responsibility for the oil rig's maintenance - even though it was operated by Transocean - as well as the cement work on the well and the inspection requirements for the oil spill-prevention system, whose failure was the final trigger for the disaster.
The report contains dozens of recommendations for improving industry safety, including suggestions for improving spill-prevention systems and ensuring that rig engines do not absorb gas.
It also says rig operators must be required to provide better reports on their drilling processes to the government, which for the first time would monitor problems at oil wells.
Lastly, it points to the possibility of renewing surprise inspections at Gulf oil rigs, a practice that had been discontinued in recent years.