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Comment by btilly | Hacker News Reader

Short summary, the integrity of the well seems to be compromised below the layer we can reach. Therefore attempting to cap it will just cause it to leak out the sea floor below anything we can reach. The only choice is to let the oil out and try to catch it. However this will erode the already compromised well structure.

At that point it is a race between erosion and the relief wells, which hopefully will relieve the pressure on the existing well.

If the relief wells fail to get there in time, there is a real possibility of the sea floor collapsing and letting the entire oil pocket out. The potential oil spill if that happens could be up to 2.5 billion barrels.

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If the sea floor above the pocket is so fragile, what was to stop this disaster from occurring naturally some day, without having ever drilled?

That sort of thing may very well have happened in the past. And it probably sucked being a fish for quite a while.

And like many other bad things that have occurred quite naturally in the past, we'll suffer no matter what or who's causing the disaster. When the Toba caldera blew last time, for example, we almost got wiped out.

And like many other bad things that have occurred quite naturally in the past, we'll suffer no matter what or who's causing the disaster.

So la-de-da let's go around doing things that might cause more of these things to happen, after all it's natural? Sounds a lot like the "everything natural=goodness" fuzzy thinking certain people are guilty of. Lots of bad things are "natural" yet it's still a very smart policy to prevent them. Contracting STDs is natural. Tooth decay and abscesses are natural. Breaking your neck in a fall is natural. I'm still going to practice safe sex, brush and floss my teeth, and use a safety harness while climbing.

A good many resources just don't make the cost/benefit cut. Self destructively promiscuous people are a readily available resource for getting sex, but they are also a good way to irreversibly get stuck with herpes.

From my reading, it's flow that's causing the erosion. We've punctured the dam.

Consider an earth dam holding in a lake. As long as the water's sitting behind the dam, not much is going to happen but as soon as a little crack appears or a bit of water begins pouring over the top, it starts eroding - carrying away bits of the dam. As the hole gets bigger, the flow increases which accelerates the erosion.

Now picture the oil eroding a hole in the casing and surrounding rock/silt/etc.

Here's a visual from a recent natural disaster: http://www.boston.com/bigpicture/2010/06/landslide_lake_in_p...

74,000 psi can certainly cause erosion... :(

(Not that I necessarily buy the entire article, but)

What he is saying is that the sea floor IMMEDIATELY below the BOP is soft and sandy. That may be the first 10 to 100 feet, which is basically supporting the weight of the BOP.

As another poster has pointed out, it's another 18,000 feet down from the seafloor to the top of the oil deposit.

From what this guy said, the maximum flow rate if the well fails is 150,000 barrels per day. If there are 2.5 billion barrels in the reservoir, then we'd be looking at a continuous leak at approximately three times it's present flow rate for 45 years before it stopped.

The consequences of that scenario are too horrible to imagine.

4.5 years, not 45 years.

2,500,000,000 barrels / 150,000 barrels per day / 365.25 days per year = 45.6308464522 years

This is correct. It would definitely take years. Think about that there is only one hole in this well. It is much smaller than wells in places like Texas and Middle East which are drilled via many holes for a few years.

2.5 billion barrels is about 300,000,000,000 liters, which is 300,000,000 cubic meters, which is about half a cubic km.

If any significant fraction of that volume is removed, it seems likely to me that there will be cave-ins around the bubble. If those cave-ins are big enough, they could create cracks that would cause more leaks to come out. Alternately they could produce places for oil to go that won't leak out the current hole. Or they could widen the current hole.

Of course long before that point we should have relief wells. But the challenge there is that the wells are hard to put in and the existing leak lends an element of instability. The last thing anyone wants is to have further accidents on the relief wells. But when you're hurrying under difficult circumstances, accidents cannot be ruled out.

If I'm not mistaken, that equals 10,000 times the volume spilled by the Exxon Valdez (250k barrels).

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