Various news outlets are reporting that BP's top kill effort to plug a leaking well in the Gulf of Mexico appears have stopped the flow of oil and gas and 'stabilized the wellhead.'
BP's CEO Tony Hayward was quoted by NBC's TODAY show that the top kill attempt, which involves shooting heavy drilling mud into the blown-out well 5,000 feet underwater, was 'proceeding pretty well according to plan.'
The US Coast Guard Admiral in charge of the operation, Thad Allen, told an New Orleans radio show, 'They've stopped the hydrocarbons from coming up. They've been able to stabilize the well head, they are pumping mud down it.'
hayward 3But BP's Hayward, who has been directing operations on the scene for some time, maintains that the procedure, which has never been attempted before so deep underwater, still had only a 60-70 percent chance of success, although some of the risks had been reduced.
'It will probably be another 48 hours before we know if we've met the success,' Hayward added.
If the procedure works, BP will inject cement into the well to seal it permanently. If the 'top kill' attempt doesn't work, BP says it has a number of backup plans. Either way, crews will continue to drill two relief wells, considered the only surefire way to stop the leak.
Admiral Allen notes the task is to now ensure the mud can hold the oil and gas back long enough for them to cap the well. 'The goal is to put enough mud down the well bore to the point where there is no pressure exerted back by the hydrocarbons and then allow a cement plug to be put in place,' he said.
A brief summary in the Sacramento Examiner of the technology behind the the top kill technique reveals that the top kill rig is only one of four service devices currently in place. Besides the top kill rig(s), there are the two relief wells and a vessel which is collecting as much of the spilled oil and gas as it can by using a Riser Insertion Tube Tool (RITT).
The top kill procedure BP is putting in play puts heavy drilling mud down into the well, overcoming the flow of the well and ultimately shutting it off. On the surface, two Kill Vessels (boats with lots of mud) are connected to the primary rig that will do the actual drilling and dropping. Two more Kill Vessels are on standby for redundancy.
Under the water, BP will be using the choke and kill lines from a Blowout Preventer Stack (BPS). This is a metal tower stack that connects the wellhead to a pipe that is connected to the oil rig. The pipe broke at the BPS causing the continued spill of oil. The BPS has safety lines called a kill and a choke line. These lines will be used in the Top Kill procedure as the piping to feed the well with mud. All of the procedures will be done using a Remote Operated Vehicle (ROV).
If the mud is able to stop the flow of oil, concrete will be poured over the wellhead to permanently cap this opening. In a technical presentation, Kent Wells, BP Sr. Vice President did say that another contingency is available if the Top Kill procedure fails. Lets hope this can close the spill.