Did the wrong people accept the risk?

After reading Robert X. Cringely’s post on the oil spill, I felt obliged to comment. I feel the biggest problem with the whole oil leak catastrophe is that the wrong people were accepting the risk. Here is my comment that I posted to Robert’s blog.

Every project that has some likelihood of endangering life or property needs to be prepared for the worst case, or even the worse worse case. I think that it might well be that what is happening in the Gulf at the moment isn’t the worse. I can imagine say an earthquake-induced fissure could unleash oil at maybe 10 times the current flow rate. But is anyone expecting that – probably not. I imagine since we started drilling for oil or gas, millions of wells have gone in. Maybe only dozens have had a problem within an order or two of magnitude of the problem. But clearly the probability of such an incident as we have was never going to be zero. Somewhere, someone (probably many times) would have considered the scenario we have, and probably outlined the consequences. And while some measures seem to be used in oil-drilling (such as the infamous BOP), clearly it doesn’t mitigate all possible scenarios. So what happened? Simply put, the risk was accepted. We accept risk all the time. Every time I drive to work, I accept the risk that if one of my front wheel falls off through mechanical fatigue, I will likely die. I can imagine that car builders could have mitigated this by making the wheel twice as strong, or maybe adding redundant front wheels. Wheels have detached on cars so this isn’t an unknown scenario. However the manufacturers, and to a greater extent the drivers accept this risk, as the cost of mitigation is too high to be affordable, and the probability of it eventuating is small even though the impact is large. The same goes for flying in commercial aircraft. I am sure they could build planes with an exit door on every row, and we all wear parachutes. We all could be trained to use these, obtaining an air passenger licence before we fly. I imagine this might have been considered in the past, but it will never be implemented. Partly this is due to the fact it only mitigates against some failures, that parachuting is risky in itself, and the cost and complexity of implementing it would be mean flying as we do today would just not happen. So we accept the risk.

The big difference however with the oil leak is that people doing the risk accepting are not those primarily impacted by it. BP nor the government regulators are really now impacted by the results of this catastrophe. Fundamentally all they risk is their job, reputation and some money. It would seem to me that this is the case for nearly all resource exploitation. Unless you can force those doing or regulating the resource extraction to directly live with the consequences, you are going to have what has happened. I’m not sure how you change this behaviour, without significantly impacting on our so called prosperity. Clearly every similar resource project needs to be examined and thought about in a different way. For instance for deep-sea drilling, you might need to demonstrate and deploy technical options that mean you can always close the well when the worse worse happens (if this is even possible). Of course this mechanism in itself might also go wrong, so you need to thing about this as well. Ultimately the viability of such projects is challenged, but I think that this must be so. Hopefully this will become a wakeup call for all of us – and particular for those in project development and regulation need to ask themselves “Am I morally able to accept this risk?”

Fixing a leaking oil well the DIY way

I just saw the news that the “top kill” method to stop Gulf of Mexico oil well leak has failed. I tweeted yesterday that I thought it had the same chance of success of using Blu-Tack (or chewing gum) to fix a radiator leak. While it might stem the flow for a little while, inevitable the fluid under pressure is going to find fissures and capillaries to follow and eventually hydraulicly lift the intended seal away from the surface. However, I feel all is not lost.

I regularly need to get anchorage on difficult surfaces. I am talking about mounting shelves on plasterboard (drywall) or bolting brackets to brick or concrete. To do this you can use various proprietary wall anchors. Almost all of these use some sort expanding material (plastic or metal) such that when a screw or bolt is turned, the device expands outwards into the wall. This is using basic mechanical principles of an inclined plane and/or lever. The screw of course is a inclined plane wrapped around a cylinder, and often there is two others working as wedges that expand, or some use levers in an umbrella like fashion to expand. The anchor is held fast through shear friction against the wall you are attaching to.

You can also create an expanding surface using fluid pressure. This is done in a clinical stent that is used to temporarily or permanently hold arteries or other ducts open. Some use a balloon that expands up air pressure, or some are mechanical similar to a wall anchor.

Another example is the sanding band I have for my rotary tool. It uses a screw to expand a rubber grip, which holds on to the band.

Either way, I don’t see why such a device, suitably encompassed by say a rubber sheath, could not be inserted in the well, expanded to hold fast on the wall, and the sheath would stem much of the leak. Even if it isn’t a total seal, I imagine you could gaurantee the porosity could be well less than 10mm or so. You could then pump “mud” or what have you through this anchor, into the well to stem the flow further. This stent/wall anchor would push against the sides and rely on pressure to hold it in. It could be driven either via hydraulic motors or rams to create the necessary leverage, akin to me turning the screw on my wall anchor. (A balloon stent mechanism might also work but there maybe issues of expanding a balloon 1500m below the sea).

I imagine the well bore is lined with a metal casing. There is of course a risk that the whole casing might be pulled out as the gas/oil pressure pushes against the wall anchor or seal. But I guess there is nothing stopping you inserting another anchor, if it is blown out, which can be driven against the natural earth wall left once the casing is removed. (You could even have a mechanism to drive horizontal spikes out of the anchor to get a more positive grip).

Yes there are obvious issues of working robotically at such pressures. Also the stent/wall anchor needs to be designed and built and tested to work under the needed forces. I’m not sure the state of the top of the well now, but clearly any valves or the like need to be removed, to leave a clean hole to insert the anchor/seal. My sketch below shows the 4 steps needed.

I have added a more deailed diagram below showing how the stent/anchor would operate. The hydraulic motor would drive the shaft. It would be threaded with left and right-hand threads. This way a rotation of the shaft would drive the nuts towards each other in pairs. (This is the same as how turnbuckles operate). The lever and hinge arrangement connected to the nut pairs would cause expansion of the sheath sealing the shaft. The head of the device might be complete sealed. The shaft could also be hollow to allow pumping of mud to properly seal the well.