Shale gas environmental concerns

Technological breakthroughs in methods for drilling for natural gas have opened up the possibility of vast new supplies. However, environmental concerns may turn out to be significant.

Stuart Staniford has taken a look at a study of the effects of shale-gas extraction on drinking water recently published in the Proceedings of the National Academy of Sciences. The scatter diagram below summarizes 60 drinking water wells in Pennsylvania, with distance from a natural gas well on the horizontal axis and methane concentration in the water on the vertical axis. All of the water wells with concentrations above 28 milligrams of methane per liter of water were within one kilometer of active drilling.

Methane concentrations as a function of distance to the nearest gas well for active (closed circles, defined as within 1 km) and nonactive (open triangles, defined as grater than 1 km away) drilling areas.
Source: Osborn, et. al. (2011).

Stuart also tracked down the relevance of a 28 mg/l concentration:

A dissolved methane concentration greater than 28 mg/L indicates that
potentially explosive or flammable quantities of the gas are being liberated in the well
and/or may be liberated in confined areas of the home.

There are potential huge investments to be contemplated to try to take advantage of the new natural gas resources, for purposes such as electrical generation by utilities, gas-powered cars and trucks, and refueling stations. But uncertainties about potential future regulation and litigation must make anyone cautious. I think it’s in the interests of everyone involved to identify right away where the contamination documented above is coming from and develop regulations to minimize it.

For added color, Stuart reminds us of this video:


32 thoughts on “Shale gas environmental concerns

  1. jesse

    PA has some serious issues around well design. A better question is whether these methane levels can be contained if the wells are designed and maintained properly, as the industry claims.
    Showing that methane levels can be elevated does not necessarily mean that shale-gas and coal-bed methane operations are inherently unsafe.

  2. LAC

    Do you really think regulation is the answer? If the court system works, this is a violation of property. The costs would be enormous for these companies to deal with these problems. They wouldn’t truly need regulations to figure out how to do this safely.
    Look at the ‘regs’ put in place in the gulf which also capped liability for the provision of any disasters as we saw last year. The $75M limit surely took away a significant portion of the oil companies’ fear of loss since ‘society’ would pay for their problems.
    Who will make these decisions? EPA? Soil & water? What are the unintended consequences of their regulations? As a monopoly force of regulation – do they have any true recourse to the decisions that they make on policy decisions? Or is failure tolerated and/or rewarded? Consider the SEC or other agencies -who make egregious errors – and receive more funding/power.
    Consider this: don’t regulations generally have deadweight loss that could be sorted out much more efficiently by the market? If the regs are too severe, we lose economically. If the regs are too lenient – does that mean that they aren’t fully responsible for their actions and landowners/local citizens end up paying the price?
    It appears to me that the company along with a functioning legal system would best know how to solve this problem. If they fail to correct these problems, they have the fear of going bankrupt and being under the force of the legal system. They best understand the technology and can do the research to see what they need to do to make drilling both environmentally & economically viable, right? At that point, maybe third party independent reviewers would be demanded by landowners to deem safety requirements and standards – their reputation would be their chief source of capital (or liability if they fail to make proper assessments).
    I’m not attempting to draw specific conclusions but I’m not exactly just intending to play devil’s advocate. It’s really a philosophical discussion. I think too often we delegate responsibility to agencies of the state that operate under much different circumstances than the marketplace. I’m quite confident that history has shown that the power of their control is seemingly always giving favor to either one side or the other since there is no market mechanism (along with the enforcement of property rights) that is allowed to effectively arbitrate problems.
    I’m from a farm in upstate NY and we have this very issue surrounding our communities. I view this as a serious problem. On the surface, my response may seem to be unreasonable to some. However, if the market is allowed to function, it’s not perfect, but it would solve these problems much more efficiently.

  3. 2slugbaits

    And we shouldn’t forget that methane is a much more potent GHG than CO2. That’s not an argument for having us all shiver in the cold, but it is an argument for getting the price of carbon-based fuels in line with their actual costs. jesse is probably right in pointing out that nothing in the article says extracting natural gas is inherently unsafe (I think he meant to say “necessarily unsafe”), but it does mean that unregulated extraction carries with it a very high degree of risk and that an unregulated market will almost certainly get it wrong because the price signals are all wrong.

  4. Walter Sobchak

    “I think it’s in the interests of everyone involved to identify right away where the contamination documented above is coming from and develop regulations to minimize it.”
    It would be if our society were dominated by rationality. Unfortunately, we have reached the sad state where people have discovered how to profit from being problems, rather than solving them. Their real goal is to create hysteria and misinformation to power their fund raising and their political ambitions.

  5. rjs

    we have removed mountains and the homes on them to get at the seams of coal underneath them; who would think for a minute that the likelihood of contaminating someone’s water supply would ultimately give us pause?

  6. Joseph

    Fracking is not just a danger to those living near the wells. Robert Howarth from Cornell has calculated that the net effect of burning natural gas from fracking is actually worse than burning coal in its effect on global warming. The fracking process causes the leakage to the atmosphere of more natural gas than traditional gas wells. Methane is a 20 times more potent greenhouse gas than carbon dioxide. The net effect of fracking to produce natural gas and then burning it contributes 20% more to global warming than burning coal.
    Add to that the refusal of fracking companies to disclose the contents of the chemical soup they are injecting into aquifers and you begin to realize that we can’t drill our way out of this energy problem.

  7. Anonymous

    Someone tell me what the danger of methane in my drinking water would be? Is there a simple solution to the problem? How many deaths so far?

  8. Anonymous

    You can install a well vent to let the methane evaporate into a well ventilated area.

  9. Anonymous

    If the gas problem is really bad you can also install a tank and aerate the water to remove the gases to the outside air.

  10. aaron

    Active drilling is going to happen where is there are high concentrations. Here in michigan, people are often frustrated because they are not allowed to extract the natural gas which contaminates their well water.

  11. Steven Kopits

    The average household uses 400 gallons of water per day, 70% for indoor use.
    Contamination of 28 ppm would represent 0.25 ounces per day per household for household use.

  12. Steven Kopits

    Methane decomposes into CO2 over a 10-12 year period. It’s only a greenhouse gas for a finite period of time.

  13. aaron

    I doubt soil contamination is an issue, hydrocarbons should enrich this soil. Where these contaminated wells are is also some of the richest farming land in the state. We tend to look for oil in barren land because it is a sign that there is likely a caprock that has prevented oil and gas from escaping to the surface.

  14. aaron

    It’s likely the cloud/CRF effect is responsible for half the warming this century and 1/3 or recent warming. On top of that, there are likely similar effects happening in other fluids, affecting ocean circulation (in addition to the cloud cover change over oceans) and volcanic activity. Feedbacks (probably at least 1/3) were likely wrongly attributed to greenhouse gases due to these ignored effects. Our rate of ghg emissions increase is declining, and the additional greenhouse effect decreases as concentrations increase; meaning, we’ve already seen most of the warming we will see this century (ie, the next 70yrs or so).

  15. Steven Kopits

    From CNN Money:
    Jackson thinks the sand and high pressure used in the fracking process may be weakening the well’s casing, allowing the gas to seep out. He noted that his team did not find any evidence of the fracking fluids themselves in any of the drinking water wells.
    So one of the authors of the study blames poor casing and cementing, which is a routine task in oil and gas production going back many, many years. He blames hydrofracking, that is, over-pressure in the pipes–he appears the be arguing that fracking is not only fracturing the formation 5000 ft down, but the casing and cement near the surface as well.
    This should be possible to test. The absence of fracking fluid in the formations near the well would suggest the hypothesis is wrong, but in any event, the industry has technologies to test this sort of thing.
    I would note, however, that the natural gas industry has brought this wbole issue on itself. If you let academics gather and present data, then their angle and bias will dominate the headlines. If there’s a problem with either leakage or some other techincal area, the industry needs to address it. If not, trade associations like ANGA needs to gather and present the data that bury studies like this.

  16. Mike Giberson

    Three things in the data reported all point to “regulation by contract” rather than regulation by governmental agency. (1) Distant and (2) inactive wells seem not to cause a problem, instead only nearby active wells are sometimes a problem. (3) Only some nearby active wells are a problem, others are not.
    Assuming the mineral owner is also the surface owner and has groundwater rights, then the harm caused by methane released into nearby soil primarily affects a party to the gas development contract. Property owners should negotiate for the necessary protections as part of their contracts with developers and take steps to monitor their water or soil in order to enforce the provisions. If the property owner monitors and enforces such provisions, then neighbors will also likely be protected.
    If the different between the nearby active wells that appear to be a problem and the nearby active wells that appear not to be a problem is just a quality cementing job, then developers already have the ability to cheaply avoid causing the harm. The solution is a contractual provision and monitoring sufficient to provide the incentive to perform a quality job.

  17. aaron

    Steve, I think you are probably right, but I think your assumption that fracking fluid would be present if there is superfluous fracking is incorrect. I would bet geological instability could cause a fracking without direct fluid contact.

  18. aaron

    I vaguely remember some fracking was stopped in Tenn or KY near a fault-line as it seemed to be causing tremmors.

  19. ivars

    If I were in the USA, I would focus on how to convert USA transport industry to natural gas instead of measuring the ppm’s of methane.
    Here in Europe that is so simple, as are the filling stations for liquid gas. Price is 1/2 of diesel of gasoline, even though liquid gas for automobiles is also heavily taxed. With a good equipment (most expensive) , at current prices, payback time for switch Gasoline – LNG is roughly 6000-8000 miles for a Subaru Outback 2,5 liter automatic. And that is probably not the worst consumer of gasoline that the USA drivers use.
    It seems gas prices has decoupled from oil due to shale gas, so why no action? Oil will get only more expensive, while nat gas seems to have enough supply, at least in the USA.

  20. Patrick

    Why most people in rural areas don’t have cisterns in unfathomable. Instead they put up with hard, smelly, nearly undrinkable water for the most part instead of rain water.

  21. CoRev

    A fascinating discussion of those without knowledge and we can already see the anti’s lined up with the traditional arguments.
    Let’s translate.
    1) Active wells = higher concentrations of gas.
    2) Inactive wells = low concentrations of gas.
    3) Lateral drilling is done at 3 to 7 thousand feet below the surface.
    4) Water wells/available aquifers are seldom deeper than a few hundred feet.
    Which leaves us with some a question or two. Why is 3,000 lateral feet between water and gas wells different from 3,000 feet depth?
    What was the gas content of the water wells before the gas drilling?
    If the gas leakage is from the well casing how best to improve them to eliminate leakage?
    If not from casing leakage where is it originating?
    How much is natural leakage (before drilling)?
    How much is a direct result of drilling?
    Which leads us to the big question, how valid/large is the actual gas leakage problem?
    With research and age I have become extremely cynical about environmental impact claims. Are we seeing the next round of Polar Bear-like environmental attacks? Dunno, just wonederin!

  22. westslope

    The sample selection problem in the study is glaringly obvious but clearly the industry requires better monitoring and regulations.

  23. Mike Laird

    Thanks for the chart. It helps quantify one of the two major concerns about frakking. The other, unmentioned, concern is the substances injected into the gas wells to free up the underground flow of natural gas. Whatever these substances are (many are not disclosed, though diesel fuel is one of them), they can migrate into underground water flows and end up contaminating lakes and urban water supplies far away from the drill hole source. Some quantification is needed here, as well.

  24. jim weaver

    Gasfrac – Canadian company uses LPG instead of water as a fracking “fluid” – once in the well it converts to gas after depositing the proppant and then 100% of the LPG is extracted with the shale gas.
    frack yields are higher and the # of trucks used per frac is reduced by 80%.
    most importantly there is NO WATER used.

  25. Andrew

    I’m not sure shale gas is an answer in North America. Well I guess it depends on price, and only if we continue to exclude the social and environmental costs.


    “In Art Berman’s AAPG presentation, he presented the chart in Exhibit 4 showing that within the Barnett Shale play, when the production from newly drilled wells during the last 12 months is excluded, gas production declined at a 44% annual rate. The importance of this static well analysis is that it highlights the need for producers to continually drill new wells in order to grow production, or maybe merely to offset production declines.”

    “Our guess is that a producer will need a gas price somewhere around $7/Mcf to achieve a modest return on investment”

    But if they can only make money at $7/Mcf then LNG from elsewhere will start to compete with shale gas.–53768.html?cb=1

  26. Geomancy

    The causality assumption implied here has no factual support.
    There are more active wells in areas saturated with natgas. This is not a surprise.
    There is also more natgas in well water in areas saturated with natgas. This is also what one would expect.
    Until someone shows a pre-existing water supply whose methane concentration increases when drilling ramps up, this should be dismissed as fishing for damages.
    This logic is exactly similar to someone near a gold mine who finds gold in their yard and assumes that it came from the mine. Obviously the mine is there because gold is common in that locale….gold is not there because of the mine.

  27. Jonathan

    Isn’t water also a commodity, one in short supply in much of the US? Isn’t that shortage related somewhat geographically to where this technique might be used?

  28. Jeremy

    Geomancy states,
    “The causality assumption implied here has no factual support.”
    The same can be said for man-made Global Warming from CO2. Causality has NOT been demonstrated.
    This kind of shoddy science is simply propaganda by anti-industry protagonists.
    Doesn’t anyone realize that methane is naturally occurring in sedimentary basins everywhere?
    Doesn’t it occur to anyone that tiny traces of methane in aquifers over laying active oil & gas basins is quite normal (along with a multitude of other traces of dissolved minerals/chemicals like CO2, salts etc.)?
    Are traces of methane in aquifers either unnatural or harmful?
    Are garden compost heaps, in-home toilets and holiday homes by the lake to be banned next?
    What can we do to control the methane emissions of farm animals?

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