Haven't got a fracking clue
August 12, 2013 3:26 AM Subscribe
The idea of pumping chemicals into the ground near the water table seems very risky to me. What are the chances of fracking contaminating ground water?
I am pretty sure that the probability is essentially 1 given a long enough time to allow for motility of said water to move to somewhere else where it would be groundwater. It might not contaminate exactly at the drilling site, but somewhere is bound to be downstream so that would be the site of contamination.
posted by koolkat at 4:09 AM on August 12, 2013 [1 favorite]
posted by koolkat at 4:09 AM on August 12, 2013 [1 favorite]
Well all things aside, they don't actually pump the water in very close to the drinking water aquifer - the layers they frack are usually much much deeper.
Where there has been contamination its usually been because the cement in the well failed. It may or may not be reasonable to say that cement fails with a probability of 1 on a long-enough time frame. I don't know.
But I'm gonna say this question is a little bit like when someone asked "Why are Unions So Good."
People have very strong opinions on both sides of the argument, while the reality is no where near as certain as what the pro or con camp would like you to believe.
posted by JPD at 4:58 AM on August 12, 2013 [5 favorites]
Where there has been contamination its usually been because the cement in the well failed. It may or may not be reasonable to say that cement fails with a probability of 1 on a long-enough time frame. I don't know.
But I'm gonna say this question is a little bit like when someone asked "Why are Unions So Good."
People have very strong opinions on both sides of the argument, while the reality is no where near as certain as what the pro or con camp would like you to believe.
posted by JPD at 4:58 AM on August 12, 2013 [5 favorites]
Where there has been contamination its usually been because the cement in the well failed. It may or may not be reasonable to say that cement fails with a probability of 1 on a long-enough time frame. I don't know.
Given a long enough time frame, everything that is not a universal constant fails with a probability of 1.
20th Century concrete fails on a time frame measured in decades. So even if drinking water in proximity to fracking activity could be rendered safe by intact concrete (which, I think, has yet to be shown), the risk is fairly high that the OP's drinking water will be contaminated.
posted by gauche at 5:51 AM on August 12, 2013 [2 favorites]
Given a long enough time frame, everything that is not a universal constant fails with a probability of 1.
20th Century concrete fails on a time frame measured in decades. So even if drinking water in proximity to fracking activity could be rendered safe by intact concrete (which, I think, has yet to be shown), the risk is fairly high that the OP's drinking water will be contaminated.
posted by gauche at 5:51 AM on August 12, 2013 [2 favorites]
I don't see how pumping millions and millions of gallons of contaminated water into the ground in a localized area can be anything but a near certainty of future contamination.
posted by COD at 5:58 AM on August 12, 2013 [6 favorites]
posted by COD at 5:58 AM on August 12, 2013 [6 favorites]
It's really hard to say what the chances of anything happening with fracking are because the companies that are doing it are suppressing the science done about it.
posted by entropone at 6:37 AM on August 12, 2013 [2 favorites]
posted by entropone at 6:37 AM on August 12, 2013 [2 favorites]
They are pumping the "contaminants" into a rock formation that has successfully contained volatile natural gas at a very high pressure for a very very very long time. This is more complex than contaminated runoff water that is obviously going to eventually work its way into the ground water supply. It looks like it is probably possible to do this safely. I don't know where you would find data on the risk probability that an individual operator would make a mistake on an individual project.
The environmental benefits of using natural gas vs coal are not insignificant.
posted by steinwald at 6:45 AM on August 12, 2013 [2 favorites]
The environmental benefits of using natural gas vs coal are not insignificant.
posted by steinwald at 6:45 AM on August 12, 2013 [2 favorites]
"They are pumping the "contaminants" into a rock formation that has successfully contained volatile natural gas at a very high pressure for a very very very long time."
Isn't the purpose of pumping in these "contaminants" to break up this long-term container and release the contents? Also, as pointed out above, much of the failure and resulting release of the contaminants is from the man-made structures delivering the "contaminants".
posted by uncaken at 7:12 AM on August 12, 2013 [4 favorites]
Isn't the purpose of pumping in these "contaminants" to break up this long-term container and release the contents? Also, as pointed out above, much of the failure and resulting release of the contaminants is from the man-made structures delivering the "contaminants".
posted by uncaken at 7:12 AM on August 12, 2013 [4 favorites]
Best answer: Don't we have to factor in the risks fracking offsets as well? Fracking has made natural gas so cheap it is driving down coal use which is also very environmentally dangerous on both the mining and consumption side. Drilling oil (often using the same fracking processes) is hardly harmless, even if we outsource much of that damage to other parts of the world.
posted by mikewebkist at 8:02 AM on August 12, 2013
posted by mikewebkist at 8:02 AM on August 12, 2013
"Wells used for drinking water near the Marcellus Shale in northeast Pennsylvania have methane concentrations six times higher than wells farther away. That is the finding of a Duke University study published on June 24th in the Proceedings of the National Academy of Sciences."
- via ThinkProgress
posted by coupdefoudre at 8:07 AM on August 12, 2013
- via ThinkProgress
posted by coupdefoudre at 8:07 AM on August 12, 2013
Best answer:
Part of the problem with topics that people hold strong opinions on is that people select pull quotes that match their own biases. So, for example, just going off memory, if you read the Duke University study and can translate the hand-waving, it basically said that "water wells in an petroleum producing area are likely to be higher in methane than wells not in an oil producing area." You have to carefully vet your sources and have a finely tuned bullshit detector.
If you don't know anything about well drilling, what you should understand is that it's not just a hole dug down into the ground. The well must also be lined with something so that the stuff they don't want doesn't come into the well. And even then, there's pumps and stuff in the bottom of the well, and pipes run through the well. So the pipe must be leaking and the casing must be leaking in order for oil to enter the aquifer layer, which is a couple hundred to a couple thousand feet different. In this case, what they don't want is the layers where aquifers, sand, and other things are. So as they drill, they put concrete casing in place around the edge of the borehole. And it works great, except when the O&G company screws up and over-pressures one thing and lets something else leak (unlikely, because it reduces the amount they get to take home.) Blowouts like what happened to the Deep Horizon rig in the GOM are pretty rare, especially when dealing with wells that need to be fracked to produce anything.
There's some science that indicates that casings are more likely to fracture when you are putting pressure into the well in order to perform the fracking operation. It also indicates that some movement can be created when pumping things into and out of the ground, which could actually fracture the geological layers that separate the aquifers and the oil producing layers.
Many of the types of rock that they're drilling through aren't very porous, which is why the various petroleum products haven't already mixed with the water products. However, "not very porous" isn't the same as "not porous." Again, it's possible that we don't fully understand what's going on down there.
Current science as is generally accepted hasn't said that every fracking well is going to be an environmental hazard. However, it's likely that the companies involved are cutting corners and since the technique is so new the environmental oversight is lagging severely behind.
The most likely source for contamination and pollution is problems with the equipment on the surface and lax oversight of the drilling operations. This is extremely unlikely where I am in Texas, because we have a huge long history of O&G production, but it's definitely happening in states like North Dakota and Montana where they're woefully underprepared for the task they're faced with. Texas is generally all over the O&G companies like stink on feces.
Source: Fiancée is a civil engineer with a degree in environmental engineering. We're both hippies, but understand that it'd be tough for everyone to bicycle to Burning Man. Part of her job is some of the remediation work that Texas has ordered companies to do.
posted by SpecialK at 8:42 AM on August 12, 2013 [3 favorites]
People have very strong opinions on both sides of the argument, while the reality is no where near as certain as what the pro or con camp would like you to believe.This is pretty much the case.
Part of the problem with topics that people hold strong opinions on is that people select pull quotes that match their own biases. So, for example, just going off memory, if you read the Duke University study and can translate the hand-waving, it basically said that "water wells in an petroleum producing area are likely to be higher in methane than wells not in an oil producing area." You have to carefully vet your sources and have a finely tuned bullshit detector.
If you don't know anything about well drilling, what you should understand is that it's not just a hole dug down into the ground. The well must also be lined with something so that the stuff they don't want doesn't come into the well. And even then, there's pumps and stuff in the bottom of the well, and pipes run through the well. So the pipe must be leaking and the casing must be leaking in order for oil to enter the aquifer layer, which is a couple hundred to a couple thousand feet different. In this case, what they don't want is the layers where aquifers, sand, and other things are. So as they drill, they put concrete casing in place around the edge of the borehole. And it works great, except when the O&G company screws up and over-pressures one thing and lets something else leak (unlikely, because it reduces the amount they get to take home.) Blowouts like what happened to the Deep Horizon rig in the GOM are pretty rare, especially when dealing with wells that need to be fracked to produce anything.
There's some science that indicates that casings are more likely to fracture when you are putting pressure into the well in order to perform the fracking operation. It also indicates that some movement can be created when pumping things into and out of the ground, which could actually fracture the geological layers that separate the aquifers and the oil producing layers.
Many of the types of rock that they're drilling through aren't very porous, which is why the various petroleum products haven't already mixed with the water products. However, "not very porous" isn't the same as "not porous." Again, it's possible that we don't fully understand what's going on down there.
Current science as is generally accepted hasn't said that every fracking well is going to be an environmental hazard. However, it's likely that the companies involved are cutting corners and since the technique is so new the environmental oversight is lagging severely behind.
The most likely source for contamination and pollution is problems with the equipment on the surface and lax oversight of the drilling operations. This is extremely unlikely where I am in Texas, because we have a huge long history of O&G production, but it's definitely happening in states like North Dakota and Montana where they're woefully underprepared for the task they're faced with. Texas is generally all over the O&G companies like stink on feces.
Source: Fiancée is a civil engineer with a degree in environmental engineering. We're both hippies, but understand that it'd be tough for everyone to bicycle to Burning Man. Part of her job is some of the remediation work that Texas has ordered companies to do.
posted by SpecialK at 8:42 AM on August 12, 2013 [3 favorites]
The greatest potential contamination hazard is not actually from the chemicals used to frac the well which are mostly of moderate toxicity but from heavy metals and organic compounds that come out of the well. There's actually a fracturing contractor that ran tests using only food-grade chemicals to frac gas wells but there's really no point doing that when the return water is loaded with arsenic, mercury, and benzene.
posted by atrazine at 9:01 AM on August 12, 2013 [1 favorite]
posted by atrazine at 9:01 AM on August 12, 2013 [1 favorite]
I'm surprised no one has mentioned the documentary Gasland. OP, I might give it a look, since you're interested in this topic. It was nominated for an Oscar a few years back.
posted by sevensnowflakes at 9:39 AM on August 12, 2013 [1 favorite]
posted by sevensnowflakes at 9:39 AM on August 12, 2013 [1 favorite]
Isn't the purpose of pumping in these "contaminants" to break up this long-term container and release the contents?
Not exactly. They want to be able to extract highly pressurized natural gas that is not mixed with water through a pipe. In order to do that, they have to leave the rock layers that have been keeping the natural gas in place for millions of years intact while they fracture other much deeper rock layers.
Breaking the whole thing up would just be a non-productive mess and should be illegal of course.
posted by steinwald at 9:50 AM on August 12, 2013
Not exactly. They want to be able to extract highly pressurized natural gas that is not mixed with water through a pipe. In order to do that, they have to leave the rock layers that have been keeping the natural gas in place for millions of years intact while they fracture other much deeper rock layers.
Breaking the whole thing up would just be a non-productive mess and should be illegal of course.
posted by steinwald at 9:50 AM on August 12, 2013
Best answer: The Guardian did a roundup of good resources on fracking here. The first few links are very UK-specific but if you scroll down to "Best of the Web" there are some good resources, animations of how it works, etc.
posted by Wretch729 at 10:24 AM on August 12, 2013 [1 favorite]
posted by Wretch729 at 10:24 AM on August 12, 2013 [1 favorite]
As JPD implied and SpecialK pretty much said, the failure is due to ordinary drilling issues and not specifically fracking. Water wells are usually well under 5,000 feet, usually 500 to 1,000 feet. These days, oil and gas wells are being drilled at 10,000 - 15,000 feet.
Fracking isn't the problem; it's the fact that the vertical bore runs through every layer from 0 to x depth. That's where you'll get contamination, and natural pressures from deep wells can be over 4,000 psi. Gas and NGLs (natural gas liquids) are happy to contaminate any strata they can get to, if the well bore isn't sealed.
However, this doesn't solve the problem of well contamination. It's just that "fracking" is tossed around as some sort of scary boogaloo, when fracking isn't really the problem.
Also, note that there are all kinds of other operations connected with oil and gas extraction, such as salt water injection disposal. These should be closely monitored and approved by state regulatory agencies. My experience however, as SpecialK's is, is with Texas, where this kind of stuff doesn't seem to happen often.
posted by Xoebe at 5:55 PM on August 13, 2013
Fracking isn't the problem; it's the fact that the vertical bore runs through every layer from 0 to x depth. That's where you'll get contamination, and natural pressures from deep wells can be over 4,000 psi. Gas and NGLs (natural gas liquids) are happy to contaminate any strata they can get to, if the well bore isn't sealed.
However, this doesn't solve the problem of well contamination. It's just that "fracking" is tossed around as some sort of scary boogaloo, when fracking isn't really the problem.
Also, note that there are all kinds of other operations connected with oil and gas extraction, such as salt water injection disposal. These should be closely monitored and approved by state regulatory agencies. My experience however, as SpecialK's is, is with Texas, where this kind of stuff doesn't seem to happen often.
posted by Xoebe at 5:55 PM on August 13, 2013
Also it's important to note that Oil and Gas Exploration and Production Wastes have numerous loopholes and exemptions from basic federal environmental laws included the Safe Drinking Water Act, the Clean Water Act, RCRA and CERCLA. Hooray for lobbying.
posted by Big_B at 1:02 PM on August 15, 2013 [1 favorite]
posted by Big_B at 1:02 PM on August 15, 2013 [1 favorite]
This thread is closed to new comments.
This is also interesting, "The presentation, based on data collected over 4 1/2 years at 11 wells around Dimock, concluded that 'methane and other gases released during drilling (including air from the drilling) apparently cause significant damage to the water quality."
posted by HuronBob at 3:44 AM on August 12, 2013 [4 favorites]