Sunday, June 27, 2010

Deepwater Horizon Spill: Two Months and Counting

I have already blogged a couple of times on the Deepwater Horizon oil spill, but since it has now gained the dubious honor of being the worst environmental accident in U. S. history, it's time to pay it some more attention.

Apparently most but not all of the leaking oil is now being captured and disposed of by storage or flaring, some 24,000 barrels a day. Since April 20, however, the date of the explosion and fire on the Deepwater Horizon offshore oil platform that killed eleven people and started the spill, more oil has gone into the Gulf than was spilled during the previous U. S. record-holding accident, the Exxon Valdez. That was a tanker accident, which had the advantage that once all of it spilled out of the tanker, there wasn't any more left. Obviously that is not the case in the Gulf, where an incredibly productive old-fashioned gusher on the ocean floor has been throwing out swimming pools of oil every day or so.

I mentioned in my first blog that this might be a game-changing incident for the offshore oil industry. In the short term, that proved correct when President Obama placed a six-month moratorium on all Gulf oil drilling. Just last week a judge blocked execution of that order, and we will have to wait and see if it sticks, putting thousands more oil workers out of work, probably sending most of the active rigs elsewhere so the owners can recoup their huge investments, and possibly—just possibly—preventing another accident like the Deepwater Horizon. But my guess is that this has put the fear of, if not God, the federal government, into every other drilling organization, and they are probably running the safest operations they have for many years.

Will offshore oil operations be run any differently from now on than they have been up to now? Right now it is hard to say, but one thing is certain: if the safety record improves in the future, it will be because both technical people and managerial types work together to make an already pretty good technology even better. For a technology wonk like me, just the technical details of how they're doing things right now are fascinating.

Today Adm. Thad Allen, the Coast Guard commander in overall charge of the recovery operation, described how the capping wells are being drilled. For most of the distance, the same directional drilling techniques are used that are common elsewhere in the world. It is an "open-loop" process, in that the drill goes in a particular direction determined by internal navigation systems, not by any feedback from the place where they want to get to.

But now that the hole is within a thousand or two feet of the original well, they have gone to a different method. Every so often they pull the drill string (the column of interconnected pipes attached to the drill bit) and run a sensing instrument down the hole. At the end of the hole, it "listens" for magnetic fields due to the presence of the original problem well's casing, and gives a direction and distance reading to the drillers. Armed with this knowledge, they readjust their steering, drill another couple hundred feet, and then do it all over again. Once they're just a few feet away, they know they can go straight ahead and they'll hit the casing—but this time they will be prepared with plenty of mud to stop the thing up.

Maybe I'm strange, being technically inclined, but learning this little detail about how the capping wells are being drilled makes me feel better about the whole situation. I'm not a Louisiana shrimpboat captain sitting on his hands and wondering whether to go into another line of work, and for those folks I don't think this knowledge would be much solace. But as we pointed out earlier, the same type of people—technical experts—who caused the problem are the ones best qualified to fix it. Whether that's a good thing or not is a matter for managers, regulators, legislators, and the general public to decide. But right now, we have to trust the technical types to make things better, and learning how they're going about it is reassuring to me, even though it's a tedious and expensive process that will take another several weeks to complete.

Many people want to use this accident as a reason for reconsidering our nation's energy policy as a whole. The ethanol industry, for example, is boasting about how you never see pictures of gulls and cranes drenched in spilled ethanol. In principle, I think this would be a good thing. We as a country depend too much on one type of energy source, and our dependence has gotten us in a lot of trouble in the past. But the difficulty is how to get there from here to there: how to move from the way we are now to a situation that would be fair to most people, not result in disproportionate advantages or disadvantages to certain industries or political pressure groups, and not cause huge economic or political disruptions that would make the cure look worse than the disease. Doing this with the democratic process is hard, and doing it in a top-down expert-designed way would be fraught with unintended consequences. Perhaps this disaster will indeed lead to a more unified view of our present situation and more consensus about what we should do. But first we need to get it over with, and not make any hasty, ill-considered decisions in the midst of the crisis.

Sources: Adm. Allen's June 27, 2010 press briefing transcript is posted at http://www.deepwaterhorizonresponse.com/go/doc/2931/714075/.

1 comment:

  1. I am posting for one of my commentators. He can't get blogger to let him comment. So I am essentially forwarding it. jp

    Being an engineering student (about to be an engineering alumni), I can totally comprehend the professors "ghost in the machine" explanation for the complexity of the deep water oil rig system. It is a very large system, comprised of hundreds of sub systems, and even more subsystems are implemented to monitor the system as a whole, as well as all of the subsystems. It gets very complicated very fast. Generally speaking though, the cause of a complicated failure is usually very simple. Large complicated systems contain small subsystems that get overlooked. When that simple subsystem fails, it starts a chain reaction that causes the entire system to fail. Of course, there is usually a "perfect storm" of several variables and circumstances when it comes to a catastrophic failure such as the Deepwater Horizon Rig Explosion.

    Failure analysis is a very messy field of engineering study (no pun intended). Engineers, for the most part, have to rely on empirical data to determine the cause of a failure in a complicated system. Hell, even something as simple as a screw or a bolt failing can sometimes come down to empirical guesswork.

    That was an incredibly long article just to say that he doesnt know what caused the failure because there is not enough data, and then explained to them how to get that data.

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