So, is the oil leak contained?

Travis

Misanthrope of the Mountains
Travis
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Mar 31, 2007
Messages
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Just saw a blurb that BP just announced the cap has been secured and no more oil is now leaking! :)


But some guy just called in on MSNBC and claims there's another even bigger leak from some unrelated hole a couple miles away.......wasn't there an unsubstantiated rumor about that awhile ago? :confused:
 
From what I'm hearing so far so good.

Let's hope the pressure doesn't cause another leak further down the pipe, which may or may not have been damaged in the initial explosion.

I've repaired enough 100-year old water pipes to understand the problem... fix one leak and another busts open somewhere else.
 
It's just a pressure test. They'll open it back up in a few days, or earlier if there are any problems.
 
WildCat said:
From what I'm hearing so far so good.

Let's hope the pressure doesn't cause another leak further down the pipe, which may or may not have been damaged in the initial explosion.

I've repaired enough 100-year old water pipes to understand the problem... fix one leak and another busts open somewhere else.
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I have to admit that I'm confused as to why they're risking that. Now that they have it capped, they can pipe all of it up to the surface. Wouldn't that put less strain on the system than trying to hold it all in?
 
TraneWreck said:
I have to admit that I'm confused as to why they're risking that. Now that they have it capped, they can pipe all of it up to the surface. Wouldn't that put less strain on the system than trying to hold it all in?
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I don't believe they capacity to pipe all the oil to the surface - they have been piping a quantity of oil for the last week or so, but it has not been the total volume.

Anyway, they are not trying to hold it all in with a small cap forever - just for a day or so. Then they will start letting the oil back out. I believe some will still be captured?
 
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sthomson said:
I don't believe they capacity to pipe all the oil to the surface - they have been piping a quantity of oil for the last week or so, but it has not been the total volume.

Anyway, they are not trying to hold it all in with a small cap forever - just for a day or so. Then they will start letting the oil back out. I believe some will still be captured?
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But they haven't been piping all of it because they can't capture all of it. If they can contain all of it, they can pipe all of it---or whatever flow the pipes can handle, but the excess would be capped.

I don't even understand why the test is a good idea. I'm not saying there's no explanation, just that risking rupture in a different area seems like a terrible idea, and I'm not sure what capping it vs. piping to the top gains.
 
TraneWreck said:
I have to admit that I'm confused as to why they're risking that. Now that they have it capped, they can pipe all of it up to the surface. Wouldn't that put less strain on the system than trying to hold it all in?
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sthomson said:
I don't believe they capacity to pipe all the oil to the surface - they have been piping a quantity of oil for the last week or so, but it has not been the total volume.

Anyway, they are not trying to hold it all in with a small cap forever - just for a day or so. Then they will start letting the oil back out. I believe some will still be captured?
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That seems like a pretty good answer by sthomson to what was my question also, but why do the full pressure test at all? Why not keep the pressure as low as possible by piping as much oil as possible to the surface?

I guess the answer is that they want to know that in an emergency they can completely shut the pipe off, but aren't we in an emergency? Why not at least wait until the relief well is in a position to fix the problem before a full pressure test is attempted? Maybe there is risk with the relief well and they don't want to continue it if it isn't needed?

Maybe closing the well off entirely is a prelude to pumping mud and cement down the pipe and permanently sealing the leak that way?
 
TraneWreck said:
But they haven't been piping all of it because they can't capture all of it. If they can contain all of it, they can pipe all of it---or whatever flow the pipes can handle, but the excess would be capped.
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Think of it this way: A ship can only hold X gallons. There's two ships, and they have to rotate in an out in, say, 1 day. Their capacity, then, is X gallons per day. The flow rate - X gallons per day is how much is being released into the open water.

Remember that generally, pressure and volume are inversely related - when the oil is spilling directly into the water, it is at a very fast flow rate because there is no "exit pressure" on the flow. They are capturing what they can and letting the rest remain at 0 exit pressure.

If they were to cap the pipe and only allow a flow rate of X out of the well (lower volume), they are inducing a higher exit pressure or "back pressure". This back pressure will almost certainly do further damage to the compromised well, possibly even destroying the relief wells - I don't quite know. Anyway, it is a Bad Thing.

I presume they are doing a test-cap to evaluate the structural integrity of the entire well system. If it were to start failing, they will vent the cap. If it looks strong, they will start proceedings to do exactly what you want them to do - but that will take time.
 
sthomson said:
Think of it this way: A ship can only hold X gallons. There's two ships, and they have to rotate in an out in, say, 1 day. Their capacity, then, is X gallons per day. The flow rate - X gallons per day is how much is being released into the open water.

[...]

I presume they are doing a test-cap to evaluate the structural integrity of the entire well system. If it were to start failing, they will vent the cap. If it looks strong, they will start proceedings to do exactly what you want them to do - but that will take time.
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That makes sense. I assumed they had the ship capacity to capture whatever came through the pipes, and the oil still spilling into the water was happening because of inadequate capping.
 
BP Press release...
Emphasis mine:

Well Integrity Test Commences on MC252 well

Release date: 15 July 2010

Following installation of the capping stack and in line with the procedure approved by the National Incident Commander and Unified Area Command, the well integrity test on the MC252 well commenced today.

The well integrity test will last at least 6 hours and could last up to 48 hours. During the test, the three ram capping stack is closed, effectively shutting in the well and all sub-sea containment systems (namely, the Q4000 and Helix Producer systems) have been temporarily stopped. Although it cannot be assured, it is expected that no oil will be released to the ocean during the test.

Even if no oil is released during the test, this will not be an indication that oil and gas flow from the wellbore has been permanently stopped.

Information gathered during the test will be reviewed with the relevant government agencies, including the federal science team, to determine next steps.

The sealing cap system never before has been deployed at these depths or under these conditions, and its efficiency and ability to contain the oil and gas cannot be assured.
During the well integrity test, operations on the first relief well have been temporarily stopped while the well was at 17,840 ft as a precaution.

Operations on the second relief well have been temporarily suspended at 15,874 feet to ensure that there is no interference with the first relief well. The relief wells remain the sole means to permanently seal and isolate the well.

BP Press Office London: +44 (0)20 7496 4076
BP Press office, US: +1 281 366 0265
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Even if they were piping some of the oil to the surface, there's still the issue of what they do when/if a major storm comes through and the surface vessels have to leave. I would think they'd rather know if the cap can be closed during that time, or if they need to vent into the ocean. I also wonder if changes in pressure (as they pipe to the surface, then shut it off for a storm, then begin piping again) might be more risky than maintaining a constant pressure. But I'm no expert.
 
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