7 ms·

Is there any other energy-extraction process so mind-numbingly primitive and destructive? After doing a little research on fracking recently I honestly can't th

by justsee 15y ago

Is there any other energy-extraction process so mind-numbingly primitive and destructive? After doing a little research on fracking recently I honestly can't think of any. Pumping millions of gallons of chemical-laced water under high pressure to fracture geological formations and extract gas is akin to fishing with dynamite, but the long-term environmental implications are far, far worse. Because once the underground aquifers which form part of the groundwater table are disrupted / damaged they can't be fixed. The water table becomes contaminated with fracking chemicals and the gas the process is meant to extract. What does contamination of a region's water table look like over generations? Apart from the risk to fresh water, there's also (unsurprisingly) concern over geological instability from the process. A few months ago a fracking company operating in the UK (Cuadrilla Resources) was forced to stop after two mini-earthquakes were linked to their activities: http://www.guardian.co.uk/uk/2011/jun/01/blackpool-earthquake-tremors-gas-drilling http://www.guardian.co.uk/uk/2011/jun/01/blackpool-earthquak... In France the practice is banned, and in Australia a national coalition of farmers, scientists, environmental and community groups ( http://lockthegate.org.au/ http://lockthegate.org.au/ ) has formed to oppose the spread of gas wells through prime agricultural land. The big story with fracking is the long-term economic downside. So it's disappointing that the NPR article almost solely focuses on the short-term economic upside.

josefresco 15y ago
For a nice summary of the issues in the US, watch Gasland; http://en.wikipedia.org/wiki/Gasland http://en.wikipedia.org/wiki/Gasland My wife and I enjoyed it immensely, or as much as you can enjoy a documentary about how we're destroying our own water.
- anamax 15y ago
  From http://en.wikipedia.org/wiki/Gasland http://en.wikipedia.org/wiki/Gasland "Dave Neslin, Director of the Colorado Oil & Gas Conservation Commission, offered to speak on camera with Gasland director Josh Fox during filming. Neslin requested that he be allowed to review any material that would be used in the film because "the issues are technical and complex and arouse concerns in many people." The statement concludes that "Such a discussion might have prevented the inaccuracies [in COGSS's opinion] noted above." Director Fox refused those terms, which would have given editorial control to COGCC for this segment of the documentary.[9] Letting someone know what you're going to talk with him about is not giving editorial control, it's just letting someone prepare.
jpetrosky 15y ago
First thing, I like the false comparisons. They really add to your point. It also goes to drive home that point you made in the second sentence, you know, a little research. Now, hydraulic fracturing may be primitive sounding. But compared to what? Most modern oil and gas recovery is startlingly similar. Drilling muds frequently cause some hydraulic fracture because you cannot balance all borehole pressures along the entire length of a borehole simultaneously with a single drilling mud weight. Granted these muds contain a different set of chemicals than what is used for purposefully fracturing horizontal wells. Which brings up another point which even a 'little' research should have lead you to realize. The depths where these wells are drilled are well below drinking water aquifers. In fact, all pore fluids at these depths are quite concentrated brines. You're looking at 1 km + below ground surface. There is a density barrier between these brines and the fresh, drinking water aquifers which we frequently use for tap water and farming. At the flow rates you are dealing with (cm/day to cm/year) no mixing can really take place due to the extremely low Reynold's numbers. I won't say that contamination cannot migrate, since I cannot know that, only that it is exceedingly unlikely. Furthermore, if fluids could flow freely in these formations, would we need to fracture them at all? The answer is obviously no. That would be what is known as a conventional reservoir. Hydraulic fracturing generally takes place in gas shales. These have hydraulic conductivities on the order of 10^-12 cm/s. Unless the fracture reaches a more conductive body, that fluid isn't going anywhere. Would the fluid reach a more conductive body? Its possible. It would be undesirable, since you would lose any production from that particular well. Chances are any loses would be trapped by a different aquitard (a layer with very low hydraulic conductivity). Hydraulic fractures tend to deflect when they reach such a phase interface, though. The stresses tend to not be the same on both sides of the interface. A useful analogy would be activation energy in chemistry. The gas itself is methane. Methane is produced in the subsurface naturally (which is why its called natural gas). It is concievable that greater amounts might be present in the subsurface due to hydraulic fracturing of gas shales, but this would be undesirable for everyone involved since that gas would be lost from production. Which isn't to say that leaks cannot happen, but I am aware of no such cases (and yes, I looked, this is my area of study). As for earthquakes, you have to first understand what causes earthquakes. Earthquakes are caused when the crust of the earth yields. This means that the stresses become greater than the rock's ability to withstand them. Hydraulic fracture also yields rock. There was research done in California to determine if such yielding could be used to control stresses on the San Andreas fault. It came to nothing because, presently, we are not able to drill deep enough and pump enough fluid to reduce effective stresses to sufficient levels to induce controlled yield. Furthermore, any deep mining city experiences rock bursts. These are also caused when stresses in the rock lead to yield. These feel like small earthquakes, and are picked up on seismographs just like earthquakes, but they cause no damage. I do believe we need to better understand what goes on during hydraulic fracture. It is exceedingly complex. It is not, however, akin to fishing with dynamite. Open pit mining may be a fair comparison to that, although even there your analogy falls short. I am glad you have an interest in this field, however. It is an important one with a lot of potential. Further study on your part may not change your mind, but will help you make sounder arguments. Good Luck

by justsee 15y ago

josefresco 15y ago

For a nice summary of the issues in the US, watch Gasland; http://en.wikipedia.org/wiki/Gasland http://en.wikipedia.org/wiki/Gasland My wife and I enjoyed it immensely, or as much as you can enjoy a documentary about how we're destroying our own water.

anamax 15y ago
From http://en.wikipedia.org/wiki/Gasland http://en.wikipedia.org/wiki/Gasland "Dave Neslin, Director of the Colorado Oil & Gas Conservation Commission, offered to speak on camera with Gasland director Josh Fox during filming. Neslin requested that he be allowed to review any material that would be used in the film because "the issues are technical and complex and arouse concerns in many people." The statement concludes that "Such a discussion might have prevented the inaccuracies [in COGSS's opinion] noted above." Director Fox refused those terms, which would have given editorial control to COGCC for this segment of the documentary.[9] Letting someone know what you're going to talk with him about is not giving editorial control, it's just letting someone prepare.

jpetrosky 15y ago

First thing, I like the false comparisons. They really add to your point. It also goes to drive home that point you made in the second sentence, you know, a little research. Now, hydraulic fracturing may be primitive sounding. But compared to what? Most modern oil and gas recovery is startlingly similar. Drilling muds frequently cause some hydraulic fracture because you cannot balance all borehole pressures along the entire length of a borehole simultaneously with a single drilling mud weight. Granted these muds contain a different set of chemicals than what is used for purposefully fracturing horizontal wells. Which brings up another point which even a 'little' research should have lead you to realize. The depths where these wells are drilled are well below drinking water aquifers. In fact, all pore fluids at these depths are quite concentrated brines. You're looking at 1 km + below ground surface. There is a density barrier between these brines and the fresh, drinking water aquifers which we frequently use for tap water and farming. At the flow rates you are dealing with (cm/day to cm/year) no mixing can really take place due to the extremely low Reynold's numbers. I won't say that contamination cannot migrate, since I cannot know that, only that it is exceedingly unlikely. Furthermore, if fluids could flow freely in these formations, would we need to fracture them at all? The answer is obviously no. That would be what is known as a conventional reservoir. Hydraulic fracturing generally takes place in gas shales. These have hydraulic conductivities on the order of 10^-12 cm/s. Unless the fracture reaches a more conductive body, that fluid isn't going anywhere. Would the fluid reach a more conductive body? Its possible. It would be undesirable, since you would lose any production from that particular well. Chances are any loses would be trapped by a different aquitard (a layer with very low hydraulic conductivity). Hydraulic fractures tend to deflect when they reach such a phase interface, though. The stresses tend to not be the same on both sides of the interface. A useful analogy would be activation energy in chemistry. The gas itself is methane. Methane is produced in the subsurface naturally (which is why its called natural gas). It is concievable that greater amounts might be present in the subsurface due to hydraulic fracturing of gas shales, but this would be undesirable for everyone involved since that gas would be lost from production. Which isn't to say that leaks cannot happen, but I am aware of no such cases (and yes, I looked, this is my area of study). As for earthquakes, you have to first understand what causes earthquakes. Earthquakes are caused when the crust of the earth yields. This means that the stresses become greater than the rock's ability to withstand them. Hydraulic fracture also yields rock. There was research done in California to determine if such yielding could be used to control stresses on the San Andreas fault. It came to nothing because, presently, we are not able to drill deep enough and pump enough fluid to reduce effective stresses to sufficient levels to induce controlled yield. Furthermore, any deep mining city experiences rock bursts. These are also caused when stresses in the rock lead to yield. These feel like small earthquakes, and are picked up on seismographs just like earthquakes, but they cause no damage. I do believe we need to better understand what goes on during hydraulic fracture. It is exceedingly complex. It is not, however, akin to fishing with dynamite. Open pit mining may be a fair comparison to that, although even there your analogy falls short. I am glad you have an interest in this field, however. It is an important one with a lot of potential. Further study on your part may not change your mind, but will help you make sounder arguments. Good Luck