BP begun running a crucial test on Thursday on its ruptured Gulf of Mexico oil well that could stem the flow of crude into the Gulf of Mexico, Reuters reported.  This comes shortly after the oil giant said late on Wednesday it had isolated a leak it detected in a line connected to one of a series of three valves which could halt the oil flow and was repairing it before proceeding with the test.
The process which started on Wednesday night, could last up to 48 hours. The British oil giant began the tests after getting the green light from top US government officials who had delayed the plan by 24 hours on concerns the process could irreparably damage the well.
If tests, which will be assessed every six hours, show that closing the cap might cause further damage to the well, the capping device could instead be used as part of a complex system to capture the oil and siphon it to ships on the surface.
Kent Wells, BP’s senior vice president of exploration and production, said undersea robots working a mile (1.6 km) below the surface had started shutting a series of three valves designed to ultimately stop the oil flow completely.
Critically, BP has closed the main valve in the middle of the cap, “and we no longer have flow out the top,” Wells said.
The developments will be watched by investors on Thursday as BP’s ultimate costs may hinge on how much oil is judged to have flown freely into the Gulf. The disaster is the largest offshore oil spill in US history.
The decision to go ahead with the tests was taken after a day of intense deliberation that reached President Barack Obama and his Cabinet, reflecting the stakes involved.
Retired Coast Guard Admiral Thad Allen, who is overseeing the US response to the spill, has said if tests show the well can withstand certain pressures, odds are good it could be “shut in” indefinitely.