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Guest Post: Water Contamination – Fracking is not the problem

The views expressed are those of the author and are not necessarily those of Scientific American.


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With the current negative attention and controversy surrounding shale gas drilling, the words ‘hydraulic fracturing’ or ‘fracking’ have become synonymous with something else: water contamination. But according to recent research out of MIT, the contamination of drinking water near natural gas wells is caused by something totally different. In fact, fracking has nothing to do with it.

Shale gas was long considered inaccessible and unprofitable because of the low permeability of shale formations, but recent developments in horizontal drilling and multi-stage hydraulic fracturing have made shale gas production economically viable. As a result, shale gas drilling has increased dramatically and sparked debates on the safety and environmental impacts of hydraulic fracturing.

You may have seen the commercials supporting fracking that say, ‘clean burning natural gas is the gateway to our low carbon future.’ You may have also seen the Academy Award Nominated documentary Gasland, which highlights some of the environmental risks and discusses contaminated aquifers. Some have even called for a ban on fracking. Unfortunately, in this debate, some of the facts have been clouded by misinformation, anecdotal evidence, and back and forth attempts to discredit those on both side of the argument.

So what is the truth?

Can drilling for natural gas contaminate drinking water? Yes.

Is hydraulic fracturing to blame? No.

Bottom line: water contamination does happen, but not because of hydraulic fracturing. The MIT Future of Natural Gas Study, released in June 2011, examines the causes of 43 reported environmental incidents and finds that, “no incidents of direct invasion of shallow water zones by fracture fluids during the fracturing process have been recorded.”

So what causes the contamination? According to the study, “almost 50% [of the incidents were] the result of drilling operations… most frequently related to inadequate cementing of casing into wellbores.” The table below is from the Future of Natural Gas Study and highlights the frequency and causes of incidents.

While the most common incident is groundwater contamination resulting from drilling operations, the study also states that, “Properly implemented cementing procedures should prevent this from occurring.”

But, to be absolutely clear, hydraulic fracturing is not part of the drilling process. It is part of well completions, and is typically done several weeks after drilling has stopped. This is where much of the confusion sets in. You may have heard something like this before: ‘There has never been a documented case of the fractures in a shale gas production zone migrating upward to the water bearing zones. There are thousands of feet of impermeable rock separating the two, and the rock mechanics make it a physical impossibility.’

That is true. However, that does not mean fracking fluid cannot get into the aquifer. So how does this happen? If fractures never reach the aquifers, then how does the fracking fluid get there?

It goes like this:

Sometimes, drillers have to drill through an aquifer to access a natural gas zone that is farther below. (by the way, an aquifer is an underground layer of water-bearing permeable rock. It is not an underground lake or cavern that is filled with water, like many people imagine.) If the act of drilling through the aquifer and cementing the walls of the hole is not done carefully, there is a higher chance that the cement casing can crack, leaking hydrocarbons and other fluids into the aquifer. If there is a casing leak near the water table, whatever is traveling up or down the well can leak into the aquifer. Since the fracking fluids have to travel through this pipe twice (once on the way down, once on the way back up), it can contaminate the water through the casing leak. In fact, whatever travels through that pipe can leak into the aquifer. Sometimes it is fracking fluid, but more commonly, it is methane, drilling mud or produced formation water.

Aquifer contamination can happen whether you frac a well or not, and bad cementing and casing leaks are possible in any well – vertical, horizontal, fracked or unfracked.

Now, there are significant environmental concerns related to gas drilling, but let’s put them into context. 20,000 shale gas wells have been fracked in the last ten years, and the Future of Natural Gas Study pulled 43 of the most widely reported environmental incidents, and not a single one was caused by fracking. Now, there were likely more than just 43 environmental incidents, indeed, the study mentions, “The data set does not purport to be comprehensive, but is intended to give a sense of the relative frequency of various types of incidents.”

Regardless of the frequency of incidents, any spill or leak is unacceptable, and the pressure should be on the drillers and operators to minimize the environmental impacts of natural gas production. But, the data show the vast majority of natural gas development projects are safe, and the existing environmental concerns are largely preventable.

Photo Credit:

1. Photo of anti-fracking posters by ProgressOhio and used under this Creative Commons License.

About the author:

Scott McNally has a B.S. in Chemical Engineering from the University of Texas. He has worked as an Environmental Engineer for Valero Energy Corporation, a Project Engineer for Shell Oil Company, and an energy and climate research intern for the White House Council on Environmental Quality. This is Scott’s second guest blog post at Plugged In – he was invited to be a guest blogger by Plugged In’s Melissa C. Lott. You can reach Scott via e-mail at scottmcnally at gmail dot com.

 

About the Author: Plugged In Guest Author - An energy research engineer who has worked in oil and gas, environmental engineering, renewable energy, and energy and environmental policy for the Obama Administration.

The views expressed are those of the author and are not necessarily those of Scientific American.





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Comments 37 Comments

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  1. 1. hercules411 10:23 am 01/25/2012

    Let’s accept the premise that poor drilling practices cause contamination of aquifers. But isn’t it also true that contamination from a bad vertical well would be less widespread than possibly from a “fracking” well, which also travel horizontally (sometimes in several directions) and thus cover a wider area underground?

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  2. 2. jtdwyer 12:52 pm 01/25/2012

    Isn’t fracking used to recover additional gas from otherwise depleted wells? Is the re-drilling of depleted wells common practice prior to fracking? Are both instances of cost critical, last-ditch extraction methods?

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  3. 3. scottmcnally 3:22 pm 01/25/2012

    Thank you both for your comments.
    Hercules – Yes, poor drilling execution can lead to leaks, which can sometimes get into an aquifer. The contamination rate is approximately one case per 1,000 wells. It is very rare, but it does happen.
    Contamination from vertical or horizontal wells would be equally as likely or widespread. Horizontal wells are actually shaped like a big “L”. You drill straight down 10,000 feet, then across for 10,000 feet. But, the aquifer contamination happens on the vertical part of the well, not the horizontal. The point is, it doesn’t matter what type of well you are drilling, it’s all about the drilling itself.
    Jtdwyer – When people say that fracking has been around for 60 years, they mean it in the sense to which you are referring. Fracking has historically been done to recover additional oil or gas from depleted wells. You are right. But, shale oil (like in the Bakken of North Dakota) and shale gas (Marcellus, Pennsylvania) is different. Shale wells are fracked at the very beginning of the well’s life, and can be fracked again down the road, depending on the geology and performance of the well. As for re-drilling depleted wells, this is uncommon. To frack or refrack, you would just pump fracking fluid down the existing hole, you would not need to drill another hole.

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  4. 4. mike johnston 3:34 pm 01/25/2012

    Thanks Scott for explaining things. I have been an advocate for alternative energy for many years, especially hydrogen energy. More recently I have been involved in promoting natural gas as a cleaner, domestic energy source. After the movie Gasland came out I wanted to see for myself what was going on in this industry and have seen firsthand how a well is drilled, fracked and finished. As a result I can say with confidence that Scott is exactly right in his assessment in this story.

    re: hercules411 No, a gas well in which horizontal drilling is used is no different from a regular vertical well for the first 8 to 12 thousand feet. It is at the bottom of the vertical bore that the hole is curved into a horizontal position and then extended that way. At that depth it is thousands of feet below any groundwater.

    re: jtdwyer: Yes, sometimes depleted wells can be stimulated to produce more gas/oil by re-fracking them. Fracking just creates openings in very dense (tight) rock so that the gas/oil in the rock can escape. It is more expensive than just drilling a hole into a porous reservoir but no prohibitively so.

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  5. 5. Hutchinson 3:39 pm 01/25/2012

    This seems a desperate attempt to distance fracking from the problems it faces. It will be interesting to see if the cement casings on which Industry puts so much faith can withstand the earthquake swarms being reported from many fracking sites. Both the British Geological Survey and its US counterpart have directly related fracking to earthquakes. Indeed the US military used injection of liquid under pressure to try to control earthquakes in the sixties – this is nothing new and the feigned surprise of Industry and Government makes me chuckle. The 4.0 magnitude recently on Ohio should be a warning that if you honeycomb the earths crust enough it will eventually rip. Bye bye cement casings.

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  6. 6. MoEnergySci 3:58 pm 01/25/2012

    Re: cement casings – generally, how thick are the walls that we are creating on these wells?

    In California, I know that they do significant amount of work/research in concrete (and other building materials) to withstand the numerous earthquakes that the state experiences (including some that make the 4.0 quake in Ohio look like a baby… for example, the 6.9 Loma Prieta earthquake back in the late 80s that stopped the World Series). Are drilling companies using the things learned in states like CA to do a better job in the drilling/protection steps prior to fracking?

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  7. 7. Hutchinson 4:09 pm 01/25/2012

    Can you give me a Reference for your 1 in 1000 well leakage contamination figure as Muehlenbachs estimates 50%.

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  8. 8. scottmcnally 6:01 pm 01/25/2012

    Mike – You’re welcome. Thanks for the support.
    Hutch – I am glad you brought up earthquakes. What you are referring to is called induced seismicity, and I’ve had long conversations with some folks at the U.S. Geological Survey about it. I struggled over whether to include it in this article, but decided to save it for a future story. Here is the summary: Fracking can and does cause small earthquakes in the 2.0 range (detectable by a machine, but not by humans), but to my knowledge has never caused a significant earthquake. The biggest one I have heard of is the 4.0 quake you mention in Ohio, read about it here: http://www.usatoday.com/news/nation/story/2011-12-31/northeast-ohio-earthquake/52307134/1
    The story says, “The seismic events are not the direct result of fracking.” And, “The quake caused no serious injuries or property damage.” This quake may have been caused by a wastewater injection well, but I don’t know if the true cause has been identified yet.
    Anyway, it is possible that fracking could one day cause a more serious earthquake, but with a million fracked wells in the U.S., and no significant earthquakes yet (to my knowledge), I guess you could say the odds are less than one in a million. Induced seismicity is a much greater concern with carbon capture and sequestration than it is with fracking.
    Additionally, natural earthquakes are a much greater concern than fracking induced earthquakes.
    The 1 in 1,000 is my own inference from the MIT study. 20,000 wells – 20 instances of contamination. That is 1 in 1,000. Who is Muehlenbachs? Post the link, would love to see it.

    MoEnergySci – Total thickness varies depending on the well, but it is usually in the range of 3-5 inches. The well is actually a series of ½” to 2” thick coaxial steel and concrete tubes. It is pretty resilient and the length of the tube is surprisingly flexible. As for earthquakes, the mechanics are different when you put something underground. I don’t know if the learnings in California are transferable. However, there is a lot of oil and gas production in California, and to my knowledge, earthquakes have never really been a problem.

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  9. 9. MoEnergySci 11:43 am 01/26/2012

    Thanks for the explanation, Scott.

    Curious -
    “In fact, whatever travels through that pipe can leak into the aquifer. Sometimes it is fracking fluid, but more commonly, it is methane, drilling mud or produced formation water.”

    Is the methane from natural gas (which is mostly methane) leaking into an aquifer?

    With respect to produced formation water – when I was a kid, I remember that, at the oil wells on our land, we used to also produce a bunch of salty, contaminated water (definitely not drinkable and made your skin itchy if it got on ya)… is this the same stuff? Does this water get re-injected into the well after it is produced/the natural gas (or oil) is recovered? Or is it just left in the system? Basically, I am trying to figure out how this water might have a chance to pass by a crack in a casing, and then get into nearby aquifers.

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  10. 10. scottmcnally 3:07 pm 01/26/2012

    Mo – Yes, the methane is from natural gas coming out of the well.
    Produced water varies in content, but usually it is just salty and oily. The water can be disposed of or recycled in a number of ways. Typically, it goes either into holding tanks and is piped or trucked off to be treated or disposed of in disposal wells or standard water treatment facilities. Other times it is held in evaporation ponds, and the salts or sediments that are left over are sent to a hazardous waste landfill. Produced water is usually non-toxic, but not always. Either way, I wouldn’t drink it. Thanks for you questions.

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  11. 11. wildtp 3:25 pm 01/26/2012

    I am a Petroleum Engineer who has been in the business of well stimulation (including acidizing, fracturing, waterflood mobility enhancment, and secondary/tertiary recovery methods)for 32 years now, first with Schlumberger, and now with BP America. This post is the first piece of sanity regarding the current furor over hydraulic fracturing that I have read. The assertion that hydraulic fracturing (the rightly noted COMPLETION practice) causes fractures to migrate upwards thousands of feet to contaminate drinking water aquifers is not only a bit silly, but physically impossible. In the case of the “flammable” drinking water coming from water wells around the Marcellus development, it is manifestly the result of shoddy well construction resulting in methane migration either up cement channels in the borehole casing annulus, or tubing/casing leaks as the author noted.

    If rigorous well construction is pursued, it is virtually impossible to contaminate drinking water aquifers, during the producing life of most wells. Water injection for pressure support, or produced/waste water disposal, at pressures exceeding the fracturing pressure of the disposal interval, is the only real “fracturing” activity that could possibly propagate a fracture up to a potable aquifer…unless the well were extremely shallow. Likewise, activating a subterranean fault during a completion frac job is virtually impossible, as the volumes are not big enough. The microseismic events that the author cites are actually used by petroleum industry service companies to help determine the geometry of the fractures, and the direction of the principal stresses that govern which direction (azimuth) the created fractures propagate in. I cannot say if a large water injection well, in communication with an active fault, could activate the fault and cause an earthquake that could be felt at the surface…I only know that it has never been documented. Good article Scott, thanks!

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  12. 12. vebiltdervan 5:24 pm 01/26/2012

    A couple of points, directed to Scott & to wildtp:

    1) First, Scott, I found your use of the table from the MIT study, which lists numbers of pollution incidents associated with drilling operations, & then referring to the “almost 50%” of these being groundwater contamination, to not be particularly helpful. What would be far more germane, of course, would be a statistical sampling of the number of aquifer-polluting hydrofrack wells as a percentage of total hydrofracked wells. Are cement bond logs run routinely on all these wells?

    2) To both Scott & wildtp: I would argue that the enormous pressures employed during hydrofracking are necessarily going to result in some percentage of casing cement failures, even if best completion practices are followed for all wells. Hydrofracking decreases the margin of error allowable for well completions by at least an order of magnitude over the well stimulation practices that preceded it. I doubt that it’s simply true that “rigorous well construction” will make leakage “impossible”, it will merely minimize the number of such leaks to a lower percentage. But even if rigorous well construction was infallible, it’s still a given that well casing cements will fail in some percentage of wells. Drill crews & Halliburton employees, like the rest of us, are human, & their work products will never be perfect.

    As far as I’m concerned, as a longtime petroleum geologist, there will necessarily be incidents of pollution, including groundwater pollution via casing cement failure; it’s an inevitable cost of using this technology.

    That doesn’t mean that we should simply ban fracking, but it does mean that we as a society, & the companies that drill the wells, must factor in all of the costs of producing the natural gas made extractable by fracking. When part of the cost of fracked wells is polluted groundwater, the companies that drill the wells must deduct the cost of correcting that problem (supplying bottled water to all affected residents for as many years as it takes, for example) from their profits. It’s not acceptable that the individuals who’ve lost their supply of drinking water should bear the cost alone; or that towns should bear the entire cost of treating toxic wastewater recovered from fracking operations.

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  13. 13. scottmcnally 9:52 pm 01/27/2012

    Vebiltdervan – Thanks for your comment.
    1. Aquifer sampling occurs much more frequently now as a way for industry to protect themselves. The water wells are sampled before drilling, and after. Here are your statistics: 20,000 wells fracked, 20 cases of contamination.
    2. As far as I know, the pressures used in fracking have never been determined to cause a casing failure. As a geologist, you know that downhole pressures are already very high, and the compressive resilience of steel reinforced concrete (which is also reinforced by the ground around the pipe) is also extremely high. Casing does fail occasionally (0.1% of the time), but not because of fracking. If the fracking fluid gets through the casing, it’s because there was already a weakness in the casing.
    3. I totally agree with you here. We should factor in all costs – including environmental costs- into the decision to drill. If the driller/operator causes contamination, they should bear all the clean up costs and should be responsible for the recovery (with oversight, which they should also pay for). I believe this is how it works now.
    However, we should also consider the costs associated with not drilling, including the environmental costs. Natural gas is a substitute for coal, and is widely replacing coal in the power generation sector. If we don’t use natural gas, we use more coal, which is way worse for the environment in all aspects – including water contamination. I write about this in my other post about natural gas.

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  14. 14. dwbd 10:11 pm 01/27/2012

    “…If we don’t use natural gas, we use more coal, which is way worse for the environment in all aspects – including water contamination…”

    That’s your conflict-of-interest opinion. Other objective research shows otherwise:

    “…GHG footprint for shale gas is at least 20% greater than and perhaps more than twice as great as that for coal…”

    http://www.sustainablefuture.cornell.edu/news/attachments/Howarth-EtAl-2011.pdf

    “…the existing U.S. gas fleet emissions exceed the existing U.S. coal fleet emissions by 9% to 27%…”

    “…Regardless of which GWP is used, coal likely has a lower greenhouse gas impact than shale gas out to 30-40 years for the existing fleet, and 40-50 years comparing the most efficient technologies for coal- and gas-fired generation…”

    http://www.postcarbon.org/reports/PCI-Hughes-NETL-Cornell-Comparison.pdf

    “…Possibly more troubling are the emissions of fine particulates from gas-fired power plants. Though particulate emissions are about ten per cent of those produced by coal power, the U.S. Environmental Protection Agency estimates that 77 per cent of particulates from natural gas plants are dangerously small. These fine particulates have the greatest impact on human health because they by-pass our bodies’ natural respiratory filters and end up deep in the lungs. In fact, many studies have found no safe limit for exposure to these substances…”

    http://www.davidsuzuki.org/issues/climate-change/science/energy/natural-gas/

    An excellent video showing the toxic emissions and hype of Shale Gas:

    http://www.youtube.com/watch?v=bYzU4bEfJ5U

    http://www.scientificamerican.com/article.cfm?id=marcellus-shale-natural-gas-drilling-radioactive-wastewater

    The fact is that NG is 15% imported, and cannot even come close to being able to replace Coal as an electricity generation source without massive LNG imports, largely from the Middle East, at prices ~5X domestic prices. Making it an absurd method of baseload Electricity production. Nuclear and highly limited Hydro are the only rational choices for baseload power generation. Coal for shoulder load and NG for peaking. Wind & Solar – a total waste of money.

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  15. 15. rcsalmon 7:52 am 01/28/2012

    @vebiltdervan – “What would be far more germane, of course, would be a statistical sampling of the number of aquifer-polluting hydrofrack wells as a percentage of total hydrofracked wells.”

    That would be nice, wouldn’t it? Unfortunately these numbers are impossible to obtain in most cases. Most hydraulically fractured wells were not prepended by baseline and baseline change studies of surrounding water wells previous to drilling. This, obviously, has got to change and indeed, has changed in many states. But there is another problem as well, and that is that in many states such as Pennsylvania, private water well owners aren’t required to take part in such studies, you can ask them if it’s OK for you to test their water, but there’s no guarantee they’ll give permission. This results in issues of self-selection bias as I discuss here:

    http://www.cst.net/geoscience/oil-business/128-frackers-anti-frackers-and-self-selection-bias-a-note-to-audrey

    In an ideal world, we would have gridded or randomized sample wells drilled locally and regionally into aquifers about to be penetrated by wells which will be hydraulically fractured, and have automated monitoring of water chemistry for several months prior to the onset of drilling to see what trends and changes are already taking place in the aquifer. But we don’t live in that world, and costs, landowner permissions, etc. make that impossible.

    “Are cement bond logs run routinely on all these wells?”

    You would certainly think so! But they aren’t REQUIRED, and as we’ve seen in incidents like Encana’s West Divide Creek incident, the Cabot case in Dimock, PA, and most famously the BP Macondo disaster, some crappy operators take shortcuts and don’t do the CBL prior to the frac job. I’ve long advocated that the CBL be required and some legislation and regulatory actions are coming into place to require this important test. In this hyped-up environment operators need tests like the CBL and pressure-testing, etc., to make sure things aren’t going to become a problem, for the good of the entire industry as well as their own financial well being.

    “or that towns should bear the entire cost of treating toxic wastewater recovered from fracking operations”

    PA has changed all this and put in new laws regarding flowback treatment; it’s no longer done at muni water treatment plants and discharged into surface waters like it once was:

    http://www.cst.net/geoscience/oil-business/125-2011-updated-pennsylvania-water-code-for-gas-drillers-

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  16. 16. rcsalmon 8:09 am 01/28/2012

    @scottmcnally – “Fracking can and does cause small earthquakes in the 2.0 range (detectable by a machine, but not by humans), but to my knowledge has never caused a significant earthquake. The biggest one I have heard of is the 4.0 quake you mention in Ohio”

    Whoa! Oops – you (and Hutchinson) just associated “fracking” with quakes which may be associated with wells that were never hydraulically fractured. The Youngstown well(s) are not production wells and were never “fracked” at all!

    These are injection disposal wells, NOT gas wells, were never hydraulically fractured, and any quakes they may have caused cannot be attributed to “fracking” in any way.

    It’s important to maintain the integrity of our nomenclature here, and not let the anti-fracking industry co-opt our terminology and attempt to expand the definition for their own propagandistic purposes. Good engineering and problem resolution requires isolating the specific fault or cause of a problem, in order to fix the right thing. The anti-fracking industry is very cleverly attempting to expand the definition of “fracking” to include everything even remotely connected to any oil & gas exploration and production activity. In this way, the problems with “fracking” can never be solved and are never ending. However, as you well know, in science and engineering that’s not how we do things. If there is a problem with hydraulic fracturing, we solve that specific problem with hydraulic fracturing. If there is a problem with a high-pressure, high-volume wastewater disposal well being drilled into a stressed fault zone, then we don’t blame “fracking” for it – as solving problems with “fracking” won’t solve a problem with an injection well! We solve the injection well problem (most likely by simply drilling a different location that doesn’t intersect stressed faults) and don’t turn to a completely different, unrelated process and look there for answers. It’s a matter of mental hygiene as well – don’t let these anti-frackers take your well-trained mind and turn it to mush (like many of theirs are) by referring to everything by the name we have for one specific process and no other.

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  17. 17. rcsalmon 8:21 am 01/28/2012

    @scottmcnally and @vebiltdervan – “As far as I know, the pressures used in fracking have never been determined to cause a casing failure.”

    Shouldn’t the specific target of the frac job be packed off so that frac pressures are transmitted through tubing to the target zone only and not generally extant throughout the annulus? Surface and, indeed all casing outside the target perfs shouldn’t ever be exposed to these pressures unless there is a packer problem, which you would soon detect because you couldn’t ramp up to frac pressure, isn’t that correct? Why would it be – that’d be kinda crazy, wouldn’t it?

    @wildtp – can you help us with this?

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  18. 18. ctsned 9:04 am 01/28/2012

    I’m not an expert in logic, but there’s something odd about this argument. Let me use my own form of logic.
    The only way you can frac is to drill.
    Only drilling causes the problem.
    Don’t frac = no drilling = no problem.

    And I’m not a rocket scientist.

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  19. 19. aboglesbee 1:33 pm 01/28/2012

    I am curious about how we can defend this as an unbiased scientific report when the MIT Energy Initiative is funded by companies who have a vested interest in profiting from natural gas: http://web.mit.edu/mitei/ On the bottom of the page you see they are funded by companies such as: BP, Shell, Chevron, Hebb, and other such businesses who profit from natural gas.

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  20. 20. rcsalmon 4:21 pm 01/28/2012

    @ctsned – “I’m not an expert in logic, but there’s something odd about this argument. Let me use my own form of logic.
    The only way you can frac is to drill.
    Only drilling causes the problem.
    Don’t frac = no drilling = no problem.”

    The primary piece you’re missing, from a simple logic standpoint, is here:

    “The only way you can frac is to drill.”

    You left out:

    “But you can drill without fracturing.”

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  21. 21. ejames429 12:21 am 01/29/2012

    Scott:

    With all due respect to your opinions I feel I have to ask you who are you currently working for? Who requested that MIT prepare a study or who provided a donation to MIT in exchange for the study?

    Since you work in the oil industry it would not be in your best interest to write an article contradicting the industry that pays your salary. That doesn’t mean you are wrong it just draws into question your conclusions.

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  22. 22. scottmcnally 1:02 pm 01/29/2012

    Hello everyone,
    Thanks for all your comments/questions. I’m happy to see such a lively discussion.
    First of all, let me make something absolutely clear – I am not on the payroll of any oil company. I quit Shell to go work for the White House Council on Environmental Quality in early 2011. I am currently semi-retired. I spend most of my time volunteering, traveling, and writing about science. In fact, I am not on anybody’s payroll. I draw my conclusions based on the logical, systematic scientific process. I have no obligations to anyone, except for science and fact.

    Secondly, I believe that climate change is a very serious problem. The solution is to stop using fossil fuels altogether, but you aren’t going to convince the American populous to do that. Conservation and efficiency are the best, followed by renewables/nuclear, followed by natural gas, followed by other fossil fuels.
    It is a fact that if we do not use natural gas, we will use more coal. I am trying to explain that to everyone. Natural gas has much fewer negative environmental impacts than coal. I hope we can all agree on that.

    Now, I will try to address each of your comments individually.

    Rcsalmon – You are right, the earthquakes in Ohio were caused by a disposal well. One could argue that we wouldn’t need those wells if we didn’t frac, and that it was associated with the fracking process. I totally agree with you on the nomenclature piece. In the eye of the generally non-technically minded public, any problem associated with the entire natural gas exploration and production process is being attributed to fracking, which it shouldn’t be, which is part of the motivation for this article. I agree with you on comment 14. Comment 15, I also agree with you here. I didn’t want to get too deep into the well design because it is rather esoteric and most readers probably haven’t been exposed to the jargon. But you are absolutely right on the technical details. Although, one could also argue that the extreme pressures could cause the tubing to fail, which is exceptionally rare. Thanks for your comments.

    Ctsned – you’re right, you are not an expert in logic.
    Let me extend your logic sequence here. Don’t frac = no drilling = less gas available = more coal mining = more water contamination = bigger problem.

    Aboglesbee – I don’t think you can attack the credibility or integrity of MIT. These are some of the smartest people in the world. They could easily get very high paying jobs with the best companies in America, but instead they chose to teach. And they didn’t do it for the money. If you have specific concerns about scientific details in the report, I would be happy to discuss them.

    Ejames – I do not work for anyone. I am not paid by the oil industry. On your other comment, most oil companies have renewable energy departments that research and invest in alternatives, and they often invest in university research studies. I don’t know the specific details of who sponsored which study in the MIT Energy Initiative case, but they research all types of energy, not just natural gas. They are totally nonbiased toward types of energy, and I would reassert that MIT scientists are more interested in facts and scientific discovery than they are with money.

    Thanks again everyone.

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  23. 23. ctsned 8:24 am 01/30/2012

    The writer claims my logic is wrong because of a different argument…that if we don’t frac we need more coal. Because coal is bad, natural gas is better, because fracking gas isn’t the problem, the problem is drilling.
    That’s like saying that coal is great as long as they don’t mine it. (I have a B.S. too)
    Correct me if I’m wrong….but as long as we are drilling through water there’s no guarantee that they can reverse any damage if the chemicals and gases get into the water. In addition there’s the profit motive as natural gas prices are much higher in Europe…which means much if not all of what is mined will end up in Europe…unless there are laws on the books that will prevent that …that’s where the gas will go..where the profits are higher. There are gas ports I have read about that are now converting their systems so gas can be exported rather than imported.

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  24. 24. aboglesbee 10:08 am 01/30/2012

    I’m a little disappointed that your response is merely a weak appeal to authority (also, saying I am ‘attacking’ when I merely am pointing out an important aspect to consider). As a scientist myself – I am very aware of the reputation of MIT. Yet, research ’101′ dictates you always consider where the funds that produce research are coming from. I will be standing by waiting for a scientific report produced without biased funding to emerge. I’m skeptical about climate change data produced on an oil companies dime – there is no reason I would change my tune when looking at similarly produced and lucrative data.

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  25. 25. Gaythia 10:44 am 01/30/2012

    It seems to me that industry representatives have two, somewhat conflicting, basic storylines. In the first, fracking is something that has been going on for a long time, in many wells. (Therefore, no worries.)
    In the second version, fracking is so narrowly defined that it isn’t fracking that is the problem, it is something else. (Therefore, blaming fracking is misguided, and still, no worries).
    In my opinion, the general public simply lumps the whole drilling process under the fracking label. This is logical because their concern is with the possible impact that may occur in this entire multistep procedure. That includes surface spills, drilling and hydraulic fracturing related problems, as well as waste disposal efforts.
    Additionally, several key points seem to me to have been left out of the analysis above, including:
    1. Many wells are drilled in areas that were previously explored. A new well, particularly one that uses horizontal drilling, and especially after hydraulic fracturing, may come into contact with one of these old wells. The old wells are likely not to have been cased, or not cased to the same standards as the new one.
    2. Many areas are complex geologically, such that a deep layer in one location may have surface, or near surface, exposure at another.
    3. Some areas, such as probably in Pennsylvania, and Pavillion WY, have formations in which the water bearing, coal bearing and oil and gas bearing layers are intermingled and water supplies are already somewhat precarious. In my opinion, hydraulic fracking operations cannot absolve themselves of responsibility simply because they are not the only cause of issues.
    4. Gas production tends to taper off after the first year or so. Many of these wells will be re-fracked. Some of the fracking fluids contain strong acids and other corrosive materials. How will the casings hold up over time?

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  26. 26. scottmcnally 2:27 pm 01/31/2012

    Ctsned – you are right about potential exports. If it makes financial sense to export, we will. Do you think it is bad to export domestic production?
    Aboglesbee – I am disappointed that, as a scientist, your priority is not to the data. Here is what the data (a review of all the reported cases of contamination and their causes) say – fracking has not caused water contamination. Do you think there is a problem with the data? Have a look at appendix 2E of the report. It is merely a communication of collected data. They are not making unsubstantiated claims. You can consider where the funds come, but the source of funding should not influence the scientific process. Sure, come up with other hypotheses and test them, but the process remains the same.
    Additionally, I think we can all agree that oil companies care about profits, right? They will do what is profitable. That doesn’t always mean oil. For example – Chevron is the biggest provider of geothermal energy in the world. Shell is the biggest provider of biofuels in the world. They aren’t saying oil is the only way and we should stay on oil. Some oil companies are forward thinking. Some aren’t.
    Gaythia – Industry representatives (I am not one) have two storylines, but they don’t necessarily conflict. We have been doing single stage vertical hydraulic fracturing for decades, yes. Multi-stage horizontal fracking is newer.
    The public lumps all parts of the drilling and production process under fracking. This is illogical. It would be as if every time you get sick, you go in for heart surgery. But that won’t help a broken leg. In order to fix the problem, you have to understand what the problem is.
    The four issues you bring up are all valid. They should all be taken into consideration when exploring a new field, and they can all have environmental impacts. And, these concerns will remain whether you frac a well or not. They should be considered in all cases.

    Thanks again for your comments everyone.

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  27. 27. Bops 11:28 pm 01/31/2012

    Sorry Scott,
    You work for and are paid by big oil.
    And Texas all about more Big oil.
    Are you truthful…not likely.

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  28. 28. Bops 12:13 am 02/1/2012

    After reading all the comments, I can see that Scott is a very experienced apple polisher.

    Who funds the program, makes the profits, and the data should not be questioned, ok to make small earthquakes, pollute the water, violate private property rights, lie, and export to Europe where the profit is better, and all this is just fine.

    I looked up the ballpark prices of natural gas around Europe.
    My mistake, I changed my mind to…skilled verbal con-artist.

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  29. 29. scottmcnally 10:03 am 02/1/2012

    Bops – Had to get this one right away. Absolutely everything you said is inaccurate. Except, you said I am skilled verbally, I’ll take that as a compliment. Thank you.
    You say I work for, and am paid by big oil. Tell me, who pays me? Who is it that I work for?
    I do not work for the oil industry. I am not paid by any oil company. I USED to work in the industry, hence my technical knowledge. My last job was with the White House Council on Environmental Quality. I am now retired. I am also not from Texas. I just went to school there. Texas is a great state in many ways (except for the incredible energy consumption), but I was born in Alaska, and I have dual citizenship with the U.K.
    Data should be questioned, but nobody has questioned the data. Not even you. Have you even looked at the data? Go to appendix 2E of the report. I beg you. When did I say it is okay to pollute the water? When did I say it was okay to violate property rights? Neither of those are okay.
    Natural gas drilling can contaminate water. It can. It is unacceptable. All I ask is that you blame the right thing.
    I am happy that you care enough to write. Thank you for reading my post.

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  30. 30. bucketofsquid 12:17 pm 02/1/2012

    I’m not a geologist so I can’t really address the technical aspects of the article or the fracking process. One thing I can address is the politics of those posting.

    Item 1 – The science should stand alone. This does not mean that it does. It is human nature to reach a conclusion and then find “facts” to support that conclusion. This is not the scientific method but happens in science all of the time. It is much more common in marketing and politics. Most of the arguement against the article hasn’t been of a factual nature but has been essentially political.

    There has been some actual constructive criticism which is nice to see. I’m a lot closer to understanding than I was before reading the article and discussion.

    2. – The political attacks are very simplistic and clearly motivated by a hatred of the fossil fuel industry. From the childish “no drilling = no problem” which is easily countered by a couple of possible responses such as “no drinking anything with water = no problem” or “water comes from wells so no drilling = dying of thirst” to the more challenging to refute “Scott is an experienced apple polisher”.

    I don’t really know what “apple polisher” means. When I buy an apple at the store it has been polished. It is still an apple when I eat it so I’m not sure what is so horrible about effective marketing. Green industries do this all the time.

    3. – I have no particular opinion on fracking or fossil fuels. I do know that much of the opposition to fossil fuels is based on very subjective experience and frequently second or third hand rumor. That might win elections but it makes for bad policy and should have nothing to do with science. Remember; movie makers make movies to get your money, otherwise the movies would be offered free. That is a pretty strong indicator of suspect motives right there.

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  31. 31. vebiltdervan 4:19 pm 02/2/2012

    Scott wrote, “…[AFAIK] the pressures used in fracking have never been determined to cause a casing failure…Casing does fail…(0.1% of the time), but not because of fracking…”
    Sorry but this does not address my concern at all. I apologize if I expressed my concern poorly.
    Of course no one needs to worry about fracking causing steel casing failures, but we do have to worry about massive hydrofrack jobs inducing cement bond failures behind the casing, particularly bond failures that can potentially create upward-channelling to overlying aquifer intervals. The cement immediately behind the casing experiences the maximum amount of pressure/stress produced during the hydrofracturing process. And it may also be under chemical attack, if the fluid used is at all acidic.

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  32. 32. FracMaster 5:03 pm 02/2/2012

    Frist it is well known that there are a few cases of water contamination. Most that I have seen are from old wells, 50′s era, where the surface pipe was not set deep enough or the surface pipe was not cemented to surface. Both practices were stopped many years ago by the state regulators. All state regulators require that the surface pipe be set far below any surface water. Now days the surface pipe production casing annulus is monitored and if there is ever any presssure it must be repaired or the well abandoned, the pipe pulled and many cement plugs installed.

    During fracturing the surface casing has zero pressure on it. In fact in the state of ND the surface casing must be left open to ensure there is no pressure in the surface casing.

    Finally during the productive life of the well the pressure in the wellbore is less that the pressure in the surrounding formations. Therefore if there was a leak it will go from the surrounding formations into the wellbore and be produced.

    No pollution is good pollution but lets keep things in perspective. If a well produces 1 million Bls of water it has produced alot of water. Even if all of this water were somehow get into the surface aquifer it would contaminate only as small area around the well. Aquifers contain trillions up on trillions of Bbls of water. I sure would not want to work oil company that was responsible for the contamination they would go broke.

    I would like to see some documented cases of water contamination that are recent becasue I don’t think there are any.

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  33. 33. nmihaylov 10:58 pm 02/2/2012

    Scott, I find the phrasing of your text highly misleading.
    Consider this statement of yours: “Of the 20,000 fracked wells covered by the Future of Natural Gas Study, only 43 environmental incidents were reported, and not a single one was caused by fracking.”
    Well, I read the parts of the MIT study related to the fracking risks, and here is what I found:
    Chapter 2, p. 39 (http://web.mit.edu/mitei/research/studies/documents/natural-gas-2011/NaturalGas_Chapter2_Supply.pdf)
    “With over 20,000 shale wells drilled in the last
    10 years, the environmental record of shale gas
    development has for the most part been a good one.”
    So, 20000 is not a sample you studied. It is the population of all shale wells in US in the last 10 years.
    Furthermore (p. 39):
    “Before examining these risks in more detail, it is instructive to look at data that attempt to summarize available information on recorded incidents relating to gas well drilling in the U.S. L48 onshore. It is beyond the scope of this study to examine multiple state archives to review individual well incident reports. Instead, to provide a high-level view we have extracted and combined the results from a number of reports that have reviewed drilling-related incidents in the U.S. over the past few years.
    Table 2.3 indicates the results of this analysis, while Appendix 2E provides a fuller description
    of the data set. The data set does not purport to be comprehensive, but is intended to give a sense of the relative frequency of various types of incidents.”
    So, your source for the number of incidents was not anything close to a comprehensive review, but a review of reports (THREE in total, as we will see in the Appendix 2E). The report admits that its purpose is to assess the RELATIVE frequency of the various types of incident (e.g. groundwater contamination vs. surface spills, etc.). Not the ABSOLUTE frequency of incidents (like a percentage of wells with incidents). “A high-level view” here obviously does not mean a comprehensive one.
    Appendix 2E (http://web.mit.edu/mitei/research/studies/documents/natural-gas-2011/NaturalGas_Appendix2E.pdf) states the same (p.1)
    “In order to provide some perspective on the relative frequency and type of incidents over the past several years that appear to have some connection with gas well drilling, we have summarized the results of three reports from differing sources that examine this issue, and categorized the reported incidents according
    to type.
    It is beyond the scope of this report to undertake a
    detailed analysis of all state-reported incidents —
    and we do not claim this to be a definitive analysis
    of all known incidents. Rather, it is intended to
    give a general picture of the types of incidents that
    occur and their relative frequency.”
    The text then goes on to describe THREE reports from which you “sampled” the incidents (not clear how). The language on page 2 does not allow us to know how many were the incidents described in the reports in total:
    “Of the 43 incidents reviewed, almost 50% were related to the contamination of groundwater with natural gas, as the result of drilling operations.” Were there more than the 43 incidents reviewed?
    In summary, I think there is a long stretch, if not a FRACTURE, between what you state here, “Of the 20,000 fracked wells covered by the Future of Natural Gas Study, only 43 environmental incidents were reported, and not a single one was caused by fracking”, and what is really in the MIT report.

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  34. 34. nmihaylov 11:28 pm 02/2/2012

    Just to add to the previous one.
    “Of the 20,000 fracked wells covered by the Future of Natural Gas Study…” (here) is not the same as “With over 20,000 shale wells drilled in the last
    10 years, the environmental record of shale gas
    development has for the most part been a good
    one” (p. 39, Chapter 2 of the MIT report).
    I was struck by the 20,000 figure. Who in their right mind would take samples from 20,000 wells, when sampling 1000 or 2000 would be more than enough? How much time, effort and money would take to measure 20,000 units of something? But you didn’t measure anything, as we see in the report. You took the total number of wells in USA, then took 43 incidents from 3 reports, and then put the two figures in the same sentence, as if this is a prevalence. Not so.

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  35. 35. rcsalmon 12:03 pm 02/7/2012

    “It seems to me that industry representatives have two, somewhat conflicting, basic storylines. In the first, fracking is something that has been going on for a long time, in many wells. (Therefore, no worries.)
    In the second version, fracking is so narrowly defined that it isn’t fracking that is the problem, it is something else. (Therefore, blaming fracking is misguided, and still, no worries).”

    No, the narrowly defined and specific definition of “frac’ing,” short for “hydraulic fracturing,” as referring to the application of sufficient hydraulic pressure to a formation to fracture the rock, is the ONLY valid definition for that technical term and has never been used to refer to anything else in the decades since the term was invented. And this IS the process that has been going on for a long time – in MOST wells, in fact. So these two “storylines” as you call them are talking about the same thing and do not conflict.

    The anti-fracking industry has attempted to grab our industry technical terminology, change the spelling to “fracking” because it looks bad and can be made to substitute for that other rude F-word, and expand the definition to mean everything even remotely connected to oil & gas exploration and production. This is a purposeful strategy to control the debate by controlling the terms used in the debate. They will make it so “fracking” is something that can never be fixed, it’s problems never solved, if we allow anti-frackers to change it’s meaning to be both everything and nothing at all.

    I don’t really have time right now to delve *too* deeply into this etymological battle, let me try to be short:

    - eco-communalist and anti-hydrocarbon activists a few years ago were confidently, even joyfully, looking forward to “Peak Oil,” a time when energy prices were supposed to skyrocket. Many of them saw this as the inevitable dawn of a new era when sky-high energy prices would cause a great drop in industrial production and “consermerism” and people would be forced to live more simple, more local, less materially bountiful lives. High energy prices would make all forms of low-density energy production (i.e., “renewables”) economically viable and society’s focus would change to conservation and scarcity, rather than production and growth. Hopefully capitalism would collapse without cheap energy and a society of small sharing, caring communities would emerge. Kind of like Hobbits of the Shire.
    - there were various versions of this vision of a post “Peak Oil” world, with various views of how different things would be than today. But regardless of how radical the hoped-for change, “Peak Oil” would be the driving force finally bringing capitalism and industrialization to it’s knees, and make the world one giant Greatful Dead festival. (sorry.. couldn’t help it, natural smartass here)
    - developments in hydraulic fracturing technology, associated with developments in horizontal drilling, have now turned this whole “Peak Oil” thing on it’s head, and the curve of available hydrocarbons is going UP, not down, and will continue to do so for the forseeable future as this technology is applied to the great petroleum basins of the Earth. This destroys the hopes of the eco-communalists (and fellow travelers) for a new re-ordering of society and the end of capitalism brought about by a need to adapt to a low-energy future.
    - Without hydraulic fracturing, mankind will NOT be able to access these vast stores of energy, hydrocarbon production will resume it’s inevitable peak and decline, and the dreams of eco-communalists and similar activists for a low-energy, low-consumption, zero-growth, post-capitalism society may still be realized in the current generation or soon thereafter.
    - thus the true target of the anti-hydrocabon activists, eco-communalists and others MUST be hydraulic fracturing. For it is that technology that is going to allow the continued existence of capitalism and materially bountiful, energy-rich lifestyles. Just when they thought all that was about to come to an end, current horizontal hydraulic fracturing methods are going to prevent that end from happening. Hydraulic fracturing MUST be stopped, in their view, or society won’t “progress” to a post-capitalist, simpler, low-energy, local-community based culture.
    - So their real target is to destroy the ability to use horizontal hydraulic fracturing. However, when early on they attacked that directly on it’s merits, they soon realized that the industry could simply, over time, answer and solve every complaint and every problem anti-frackers came up with. If the industry solves all the problems and concerns with hydraulic fracturing, they won’t have anything left to destroy it with, and they’ll NEVER get rid of it. High energy consumption and capitalism will continue – they don’t want that!
    - THEREFORE, they took to EXPANDING the definition of “frackng” to include every possible activity even remotely associated with hydrocarbon production. That way they would NEVER run out of faults to find and ways to whip up public fear and sentiment against “FRACKING” in an effort to destroy a perfectly good technology through political means, and not because there is anything actually wrong with it that.

    Just remember that. Without hydraulic fracturing, hydrocarbon production comes to an end, including old production that has been around for decades. Hydraulic fracturing is vital in extending the lives of old fields, and old-style vertical, non-shale wells. The eco-communalists surely have realized this by now, and so NOW, if they can end ALL “fracking” by political and legislative attack, they might HASTEN the coming of “Peak Oil” and get the world back on what they see as a “progressive” schedule.

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  36. 36. scottmcnally 4:48 pm 02/9/2012

    Hello everyone,
    Thanks again for all your interest in this topic.
    Bucketofsquid – Thank you for your comments. I agree that scientific discussions should center on facts and data, rather than politics.
    However, it appears that I have made a factual error myself. My concluding paragraph alludes to something that is not true. There were not 43 total incidents in 20,000 wells. There were 43 incidents that were reviewed by the study. There may have been more, and this study was presenting a representative sample, not a comprehensive list. My final paragraph should have said:

    Now, there are significant environmental concerns related to gas drilling, but let’s put them into context. 20,000 shale gas wells have been fracked in the last ten years, and the Future of Natural Gas Study pulled 43 of the most widely reported environmental incidents, and not a single one was caused by fracking. Now, there were likely more than just 43 environmental incidents, indeed, the study mentions, “The data set does not purport to be comprehensive, but is intended to give a sense of the relative frequency of various types of incidents.”
    Regardless of the frequency of incidents, any spill or leak is unacceptable, and the pressure should be on the drillers and operators to minimize the environmental impacts of natural gas production. But, the data show the vast majority of natural gas development projects are safe, and the existing environmental concerns are largely preventable.

    This error will be corrected immediately.

    Thanks again for your comments.

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  37. 37. rcsalmon 11:16 am 02/13/2012

    I’m sure some may think that my post discussing eco-communalism and primitivism as primary root philosophies of the anti-fracking movement was mere conjecture. That I’m overreaching for a cohesive intellectual framework to explain the motives and actions of anti-frackers, when really it’s just groups of local folks worried about their local water wells and air quality. Maybe I’m wrong and there is no central “behind the scenes” philosophy driving the anti-fracking hysteria. Maybe this whole thing really is about protecting water supplies and air quality, etc., and there’s no hidden goal of ending ALL hydrocarbon production ASAP so mankind is forced into a post-capitalist, zero growth, local, simple and small culture by a lack of inexpensive, high-density energy.
    Well, arriving just in time this week to help make my case, the “Gasland” group on Facebook posted this:

    “If you read anything all week, read this. Bill McKibben on the “Carbon Bubble”
    Key quote: “If we spew 565 gigatons more carbon into the atmosphere, we’ll quite possibly go right past that reddest of red lines. But the oil companies, private and state-owned, have current reserves on the books equivalent to 2,795 gigatons — five times more than we can ever safely burn. It has to stay in the ground.
    Put another way, in ecological terms it would be extremely prudent to write off $20 trillion worth of those reserves.”

    The author of this “Carbon Bubble” piece is Bill McKibben, one of the leaders and stars of eco-communalist philosophy. Recently he’s built much of his fame from founding 350.org, the leading Global Warming activist group. Bill is an anti-technologist who hates electronic media and scientific agriculture, and preaches against economic growth. He praises the lifestyles of impoverished and backward Bangladesh as “An Alternative To Progress,” apparently believing we’d all be better off living as dirt-poor peasants. He believes that the only viable answer to Global Warming and a stable economy is: “And here’s what I think the outcome boils down to: hyperindividualism versus community. If we can build a society where a community farm, a community source of energy, a community radio station, a community bookstore make sense, then we have a fighting chance.”

    So here is Josh Fox and the “Gasland” crowd, telling “Gasland” followers that the most important thing they can read this week is an essay by Bill McKibben arguing that mankind must leave the Earth’s hydrocarbon energy reserves in the ground and do without it. As is always the case with that crowd, no explanation of what we’re supposed to do for energy is provided, or, seemingly, even considered. I suppose if you think the lifestyle of a Bangladeshi rural peasant is superior, then you don’t worry about energy very much.
    At any rate, I feel these statements by the “Gasland” bunch confirms what I said in my previous post, and what I’ve been saying for a couple of years now: solving any environmental problems related to hydraulic fracturing is NOT the goal of the anti-fracking industry. Destroying man’s ability to use hydraulic fracturing through political means by attacking it with baseless fear-mongering and propaganda is their goal, because they believe, correctly, that this will destroy our ability to produce hydrocarbons.

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