The vital relief well being drilled to halt BP’s giant Gulf of Mexico spill could be finished ahead of schedule, the company has said.
And the US government’s National Incident Commander Admiral Thad Allen said he expected to break into the Deepwater Horizon well pipe about 5500m below sea level within seven to 10 days.
But they will not know how long it will take to stop the oil until they get there. The leak has multiple rings, and oil could be coming up through several of them..
The plan is to pump heavy mud and then cement into the well to overcome the upward pressure of the huge oil reservoir below.
If the oil is coming through the outer ring of the well, they will have to pump in mud and cement to stop that layer first. Then they would have to drill through the hardened cement and repeat the process in each ring until they reach the centre pipe and do it again.
That would push into the middle of August, which is the timeline the company and government officials have held to for weeks, despite repeated reports that the drilling was ahead of schedule and the oil could be stopped as soon as late July.
“If you have to exhaust all means for the ways that hydrocarbons are coming up the pipe, then that puts you into middle August,” Adm. Allen said.
If the oil is only coming up the centre pipe, then it is possible to stop the leak sooner.
A BP spokesman said late July had been suggested as a completion time if everything was ideal. A single major storm is enough to cause delays. which is why the company is sticking with mid-August.