[fso301]

I thought these things had some sort of shutoff valve sitting on the bottom. Did some manager decide to cut corners?

[thackney]

There is a large Blowout Preventer on the sea floor.

It is multistage and certainly not cheap.

It did not fully actuate and when robot submarines tried to manual actuate it has not shut off the flow.

My personal speculation is that it nearly closed, but not completely. The flow rate from the well is only 29 gpm, or about 3 garden hoses. It seems to me that it is partial shut off.

[thackney]

ROBERT, La. - A file photo shows a view of the Deepwater Horizon Blowout Preventer, Sunday, April 25, 2010. The unified command has approved a plan that utilizes Remotely Operated Vehicles (ROV) in an effort to activate the blowout preventer on the sea floor and to stop the flow of oil that has been estimated at leaking up to 1,000 barrels/42,000 gallons a day.

- - - - - - - -

ROBERT, La. - A robotic arm of a Remotely Operated Vehicle (ROV) attempts to activate the Deepwater Horizon Blowout Preventor (BOP), Thursday, April 22, 2010. In addition to the use of ROVs, the unified command is mobilizing the Development Driller III, a drilling rig that is expected to arrive Monday to prepare for relief well-drilling operations, to stop the flow of oil that has been estimated at leaking up to 1,000 barrels/42,000 gallons a day.

Gulf of Mexico - Transocean Drilling Incident - Coast Guard
http://www.deepwaterhorizonresponse.com/go/site/2931/