The Shell guy’s discussion of the “safety case” is quite instructive. Everyone involved in one of these operations needs to fell like they’re on a Saturn V that could explode at any time that the key safety measures are breached.

BP didn’t seem to “get it”. Procedures & responsibilities for responding to well emergencies seem not to have been clear.

Significantly, six executives, including a VP who has now been named a “person of interest” in the investigation, were on board the Deepwater Horizon at the time of the explosion. They were there to celebrate the rig’s impressive safety record.

Unfortunately, managers measure the easily measurable. Safety process evaluation becomes a numbers game & focuses on paperwork & lost time accident statistics. Government intervention only makes this pattern worse.

Measuring safe well design and operating practices is much more difficult, and 1000x more important. Shell seems to have a leg up on BP in that regard. I doubt you’ll find bypassed safety controls on a Shell rig.

Something about the wordpress editor seems to truncate it.

Shell color-coded “barriers” in pink.

#1, Shell’s point (and the drilling experts I respect agree) that in a well with high bottomhole pressure such as this one, you run a drilling liner instead of a full string, all at once. A short section of 7″ pipe would be run to bottom, cemented, and sealed off at its top against the next bigger size pipe, which is probably 9-5/8″. Later, that assembly is tied back to the top of the well, and that in turn is cemented in place, with cement left inside the pipe to be drilled out in the future, upon completion. I circled all that in red.

#2. BP failed to get a good seal at the top of the well on the annulus between the long string and the 16″. The engineer in charge of this process seemed very inexperienced during the investigative questioning.

Shell alludes to another potential problem: the large cross sectional area between the long string and the 16″ at the top creates a large area for the piston force of well pressure to act against if gas were to leak up the “backside”. It could be a large enough force to pull the long string in two.