BP Macondo Disaster, Week Two

 |  Includes: BP, CAM, HAL, RIG, STO
by: Retired User

This is a follow-up article to my Notes on the BP Macondo Disaster .

Very briefly, let's start with the oil slick. This weekend's Wall Street Journal noted that 600 areas of the Gulf of Mexico naturally seep about 500 million barrels of oil annually. But the threat that BP (NYSE:BP) and government agencies are grappling with is

concentrated spillage from the Deepwater Horizon well [that] overwhelms the natural background levels [of oil seep].

Estimate of the clean-up cost is $10-15 billion, could go higher.

Alabama is worried about its tourist beaches. Coastal marshes in Mississippi could be affected. Louisiana's $3 billion seafood industry and two large National Wildlife Refuges will take a direct hit from Macondo, now leaking an estimated 25,000+ barrels a day according to NOAA.

BP has four strategies to stop the leaking well. Their best bet is relief wells, which will take 60-90 days to drill laterally to intersect a 7-1/2" pipe and kill the well with heavy mud and cement.

If they succeed in halting oil and condensate flows to the sea, I will be amazed, because a BP diagram shows them drilling horizontally half a mile through the Macondo oil reservoir at -18,000 ft to the bottom of the blown well.

It makes perfect sense commercially to get two or three horizontal wells into the Macondo reservoir that BP can put into production, but I don't see this as a failsafe plan to kill the vertical well that sank Deepwater Horizon. Why not plug the top of the well - or aim for a much larger diameter section of casing above the gas-prone pay where Deepwater Horizon lost mud circulation and where the cementing failed?

In any case, ultradeep horizontal wells cost $150 million each. If they're plugged & abandoned by BP-Transocean-Halliburton exactly like the other well was -- uh, is that safe?

Who the hell gave them a nod nod wink wink get out of jail free commercial permit to hustle hurry up drill two or three high-pressure, high-temperature horizontal wells across the reservoir?

Lemme guess, using subsea blow-out preventers again?

The fact that the BOP was on the wellhead 5,000 ft under water, not at the top of the marine riser or right below Deepwater Horizon's drill floor, contributed to the blow-out disaster in two ways. The doomed drilling crew undoubtedly perceived that they had a well control problem at some point and fired the BOP shear rams to close off the well. It didn't work because [informed speculation] a mechanical test plug or drill string joint got jammed in the shear ram. Next they tried to trigger other sections of the BOP stack.

But the Cameron BOP couldn't do it. If a command to open or close a ram isn't fully completed (jammed), then its 'mux' communication logic wouldn't accept another command. And by that time, it didn't matter. A giant gas bubble was racing up the riser.

A second topside BOP could have saved the drilling crew and rig. But the procedures that the men were following invited disaster, and it happened so fast [informed speculation] that a topside BOP with automatic blow-out sensors was not the solution they needed, although I suppose it will be required by new safety regulations in the future. The best and most urgently needed safety solution offshore is to take control away from the operator, in this case BP, and give drillers an absolute veto over company men. That's all the safety that deepwater rig hands actually need.

I know that's like saying seat belts and airbags are a dumb idea -- and in fact that's exactly what I intended to convey, because we're not talking about passenger cars driven by millions of average Joes and Janes who need to be protected from drunks and antler waving young bucks at the wheel on a Saturday night.

Requiring additional safety equipment on offshore rigs, like redundant surface BOPs and automatic blow-out sensors, is an invitation to dumb down the drillers. You might as well buckle them in with seat belts and put airbags on the pipe, so they are incapable of doing anything dangerous. It would terminate every pressure kick with automatically sheared-off drill strings and lost tools.

The reality of drilling is knowledgeably dealing with danger, lots of it, including sudden high pressure kicks. I'll end this article with a recent forum post by a driller who succinctly addresses the question of safe well control.

Before you read his comment, I'll mention that I'm now convinced M-I Swaco did not have a tool downhole at the time of the blow-out. They were offloading mud to a service vessel. Responsibility for the disaster belongs squarely and absolutely to BP who ordered hustle hurry up displace the mud with seawater and disconnect the riser to move the rig to its next location.

My position in the oil patch has changed since I started as a roustabout in 1959. I am currently a consulting HPHT well design engineer. Working with 450 deg F and 12,000 psi reservoir pressure.

Funny thing, in 50 years of kick after kick I have not had a blowout.

Revised uninsured liability forecast:

BP: $6 billion clean-up, $1 billion litigation, $3 billion compensation, $4 billion lost revenue

RIG: $500 million legal expense, $500 million lost revenue

CAM: $100 million legal expense

HAL: $300 million legal expense

STO: $2 billlion lost revenue Norwegian offshore drilling moratorium

Disclosure: Usual disclaimer that all of the foregoing are personal opinions, not statements of fact, which may be wrong, unfounded, incomplete, inaccurate, speculative and/or conjectural. No position in any of the companies mentioned or any other company affected by the Macondo disaster.