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
Environmental impact of the Deepwater Horizon oil spill that the damage from the spill would rapidly resolve, three years into the recovery dolphins continue to die, fish are showing strange lesions, corals in the gulf have died and oil still remains in some marsh areas. Due to both its size and the way it was handled, there is little previous research to predict long-term effects. At the 2013 "Gulf of Mexico Oil Spill and Ecosystem Science Conference", oceanographer David Hollander presented data that showed as much as one-third of the oil released during the spill may still be in the gulf. Researchers described a phenomenon called "dirty blizzard":