Mitsui Oil Exploration Mitsui Oil Exploration It was one of 17 Mitsui companies that were spun off on July 19, 1969. Its core areas are Thailand, where it drills principally in the Gulf of Thailand in conjunction with Chevron, and Vietnam and Cambodia. In the United States Mitsui's subsidiary is MOEX USA Corp and is headquartered in 9 Greenway Plaza in Houston. In September 2007 it established subsidiary MOEX Offshore 2007 LLC which entered into a partnership with BP for drilling in the Gulf of Mexico. On April 20, 2010, its rig the Deepwater Horizon exploded and sank, causing a massive oil spill.
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":