Deepwater Horizon oil spill 17 of whom were treated for injuries. The Deepwater Horizon sank on the morning of 22 April 2010. The oil leak was discovered on the afternoon of 22 April 2010 when a large oil slick began to spread at the former rig site. The oil flowed for 87 days. BP originally estimated a flow rate of . The Flow Rate Technical Group (FRTG) estimated the initial flow rate was . The total estimated volume of leaked oil approximated with plus or minus 10% uncertainty, including oil that was collected, making it the world's largest accidental spill. BP challenged the higher
Deepwater Horizon oil spill a 193-page report on its web site. The report places some of the blame for the accident on BP but also on Halliburton and Transocean. The report found that on 20 April 2010, managers misread pressure data and gave their approval for rig workers to replace drilling fluid in the well with seawater, which was not heavy enough to prevent gas that had been leaking into the well from firing up the pipe to the rig, causing the explosion. The conclusion was that BP was partly to blame, as was Transocean, which owned the rig. Responding to the report, Transocean