Shale Gas - aquifer contamination a consequence?

[Ophiolite]

Between 2006 and 2010 shale gas production in the US increased by 600%. The process involves drilling into gas rich shales then fracturing these to provide sufficient permeability to bring production rates up to commercially viable levels.

 

Gas shales have relatively low porosities, typically less than 10%, and very low permeabilities. Much of the gas is adsorbed on the clay surfaces, though some is present in the pore space. Hydraulic fracturing at very high pressures generates very long fractures that penetrate deep into the formation and provide a conduit for free and adsorbed gas to reach the borehole and production tubing.

 

Claims have been made that the fracturing has led to contamination of much shallower aquifers. Although I have not studied specifics of individual applications, I have provisionally concluded - based on industry experience - that if contamination is occuring then, in most instances, it will be a consequence of poor well planning (casing setting depths, grades, cement program etc.), or poor implementation of that plan, especially a poor cement job, rather than a direct consequence of the fracturing, or fracing process.

 

This article from PNAS offers another possible source, a natural one, for aquifer acontamination.

 

Warner, N.R et al "Geochemical evidence for possible natural migration of Marcellus Formation brine to shallow aquifers in Pennsylvania." PNAS July 24, 2012 vol. 109 no. 30 11961-11966

 

Abstract

The debate surrounding the safety of shale gas development in the Appalachian Basin has generated increased awareness of drinking water quality in rural communities. Concerns include the potential for migration of stray gas, metal-rich formation brines, and hydraulic fracturing and/or flowback fluids to drinking water aquifers. A critical question common to these environmental risks is the hydraulic connectivity between the shale gas formations and the overlying shallow drinking water aquifers. We present geochemical evidence from northeastern Pennsylvania showing that pathways, unrelated to recent drilling activities, exist in some locations between deep underlying formations and shallow drinking water aquifers. Integration of chemical data (Br, Cl, Na, Ba, Sr, and Li) and isotopic ratios (87Sr/86Sr, 2H/H, 18O/16O, and 228Ra/226Ra) from this and previous studies in 426 shallow groundwater samples and 83 northern Appalachian brine samples suggest that mixing relationships between shallow ground water and a deep formation brine causes groundwater salinization in some locations. The strong geochemical fingerprint in the salinized (Cl > 20 mg/L) groundwater sampled from the Alluvium, Catskill, and Lock Haven aquifers suggests possible migration of Marcellus brine through naturally occurring pathways. The occurrences of saline water do not correlate with the location of shale-gas wells and are consistent with reported data before rapid shale-gas development in the region; however, the presence of these fluids suggests conductive pathways and specific geostructural and/or hydrodynamic regimes in northeastern Pennsylvania that are at increased risk for contamination of shallow drinking water resources, particularly by fugitive gases, because of natural hydraulic connections to deeper formations.

[iNow]

Summarized: Even though in some cases frakking is the cause of contaminated wells, in many cases it is not, and that contamination was already present in the absence of frakking activities. However, evidence suggests frakking makes previously contaminated wells quite often worse.

 

Is that a reasonably accurate summary, IYO?

[Ophiolite]

Not exactly - and I stress this is just my opinion, but it is an opinion informed by thirty years in the drilling industry. The frakking has almost nothing to do with it. I suspect insufficeintly robust casing and cementing programs, or ones that are not properly implemented are the root cause. These should isolate the aquifers from any other part of the borehole, including the production zone, which will also be isolated. If the cement job is poor then migration of fluids could occur between any zone and any other. High pressure gas would naturally tend to migrate upwards, and eventually penetrate the aquifer.

 

The solution, if my suspicion is correct, is then to raise standards on cementing processes rather than to question the frakking. For example I hear vigorous objections to the fluid used to fracture the shale. Frankly this is irrelevant. If the job is done correctly, that fluid will never come anywhere near the aquifers. If it does reach them, then no matter how benign it is the process is faulty.

[Enthalpy]

According to my superficial understanding:

 

- Usual production taps oil and gas from a reservoir, which has accumulated them as they migrated from their initial rock, because the reservoir is tight.

 

- The initial rock has no tight cap. It keeps the oil and gas because the rock has a sufficiently low permeability.

 

So when production fractures the initial rock to make hydrocarbons mobile, these aren't confined in a reservoir nor exclusively to the drilling well. They spread all around.

 

There is more. A single reservoir gives much hydrocarbons from a single well, as the reservoir is porous and extends to many kilometres. Shale oil or gas needs many holes because each hole gives access only to the extension of the fracturation. As boring a hole is traditionally a polluting operation, you get more dirt if producing the same amount of hydrocarbon from shale oil or gas.

 

Anyway, companies involved in these trials have lost heavy amounts of money, so the debate may soon be over.

[Ophiolite]

Your understanding, as you noted, is incomplete. You have correctly identified some key contrasting characteristics of shale gas and conventional oil and gas reservoirs. The latter have comparatively high porosities and, crucially, high permeabilities. The former have modest porosities and low permeabilities. The objective of the fracturing is to improve that permeability.

 

Increasingly conventional oil and gas reservoirs are smaller and of lower permeability, so that multiple wells and horizontal wells through the reservoir are needed to achieve adequate production levels. The technologies developed for these wells is now being applied to access the shale gas plays.

 

Your concept of the mobility afforded the hydrocarbons by fracturing is a distorted one. The point I emphasised in my opening post applies here - just as it does to conventional oil and gas reservoirs. It is essential that through proper planning, and implmentation of that plan, that the casing and cementing program, and the completion program, properly isolate the reservoir from other portions of the well. Fracturing per se does not give an unlimited licence to the hydrocarbons to migrate indiscriminately.

 

These are not trials. Companies are assuredly not losing money. (I'm sure as in any business venture there are exceptions.) You do not achieve a 600% increase in shale gas output through conducting trials. You do not have hundreds of rigs engaged in drilling into shale plays in the Williston Basin, the North East states and the Permian Basin as part of a trial.

[iNow]

I would be curious to learn more about how they can put a decent and sturdy casing in place when drilling horizontally and using a slurry to shatter the surrounding areas of the bore hole (since that's what breaks open the gases). One would think a separate hole would need to be drilled and filled at a higher depth than the extraction hole to offer good enough protection to the surrounding area.

[Enthalpy]

Casing and cementing applies only locally to the bore. In a traditional reservoir, hydrocarbons have been held in place for millions of years by a tight capping geological layer, which is not the case in shale.

 

Without the natural cap, and if fracturing the rock, casing and cementing won't help a bit.

 

I'm fully confident that fracturing, which is conducted from kilometres distance, without sight, in an imprecisely known terrain, will sometimes extend beyond the compact rock into permeable terrain, letting hydrocarbons leak.

 

Even if oil companies were Nature-minded (History shows, err, exceptions) errors do happen, and they are logically more probable - understand, more frequent - with shale oil.

[overtone]

The notion that the "fracking itself" is not usually the major problem seems a distinction without a difference. If true - and it will be years before we know - so what?

 

The discovery that shallower aquifers do have natural connections with deeper formations in the area, is not evidence for the safety of fracking.

 

And the fact that they didn't know this years before they fracked the first well in the area is proof,

 

(if any were needed after we were informed a few months ago that for the first time they were actually going to collect baseline data on the water supply of the affected area before drilling)

 

that this whole operation was launched without due diligence, without the slightest consideration for the integrity of the aquifers or the welfare of the residents or the health of the environment in the region.

 

Shut it down until after the preliminary research, at least, is done.

[iNow]

But then we'd have to replace the lost natural gas with the much dirtier coal or additional imports of crude from enemy nations.

[overtone]

But then we'd have to replace the lost natural gas with the much dirtier coal or additional imports of crude from enemy nations.

Anything's better than sacking your aquifers.

 

Even paying extra for imported natural gas.

 

Even dealing with the horrible unAmerican inconvenience of solar.

 

Even making drilling companies do their basic research in advance, not lie to everybody about what they're up to, and pay for their damages.

 

Radical notions, true - but these are unusual times.

[iDevonian]

Not exactly - and I stress this is just my opinion, but it is an opinion informed by thirty years in the drilling industry. The frakking has almost nothing to do with it. I suspect insufficeintly robust casing and cementing programs, or ones that are not properly implemented are the root cause. These should isolate the aquifers from any other part of the borehole, including the production zone, which will also be isolated. If the cement job is poor then migration of fluids could occur between any zone and any other. High pressure gas would naturally tend to migrate upwards, and eventually penetrate the aquifer.

 

The solution, if my suspicion is correct, is then to raise standards on cementing processes rather than to question the frakking. For example I hear vigorous objections to the fluid used to fracture the shale. Frankly this is irrelevant. If the job is done correctly, that fluid will never come anywhere near the aquifers. If it does reach them, then no matter how benign it is the process is faulty.

 

Even with sufficient cement and casing works, I still would not suspect this work to be environmentally friendly. The sheer number of boring holes and the vast amount of fluid used in the entirety of these operations is going somewhere. It doesnt just dissapear, and it is challenging to treat.

 

Granted, the effects are probably very minor, but over time, with thousands of wells drilled, it is near impossible not to contaminate local aquifers. Realistically though, there are far worst things that harm people in this world that are being overlooked. I am not against hydraulic fracturing, though people do have a point when they complain about contamination of local wells.

 

And yes, in many cases, cement jobs may be poor or casing may be damaged, which would be the ultimate issue, however, if it werent for an interest in fracturing, there wouldnt be faulty cement jobs and casing to begin with. It is inevitable that human error will lead to cement and casing issues.

 

Also, by disturbing the gases within these beds, they are enhancing the proportions of gases migrating into local aquifers. Not that gases like methane will kill you, though your water may be flammable, which isnt really a good thing.

 

Aside from that, there are also issues of erosion. The gas pipes used to transport recovered methane need paths built for them, and often create a great deal of erosion and runoff into local streams and reserviors. This increases the amounts of metals found in water, which can kill whatever uses that water to survive. These are all things that have happened and have been documented.

 

Ultimately, fracking harms a minority in support of providing for the majority. Just like any other fossil fuel recovery operations, or even any fuel recovery in general.

 

Also, the extent at which fractures split the rock is...seemingly impossible to fully understand. Bedding above the marcellus is not as impermeable as it is. Fracking undoubtedly enhances the mobility of gases trapped within the bed and likely frees much of it beyond areas limited to the boring.

Edited November 1, 2012 by iDevonian

[Silica]

Thisis a very interesting article by Julian Bulman, andit explains several aspects of the climate change non-debate.

 

Humaningenuity and technological advances have given us the ability to interact withour environment as no other animal or plant has been able to do through thewhole of our planets 4.54 billion year evolution in such a small andinconsequential geological timescale. This includes the ability to producesignificant earthquakes and other seismic activities using these technologicaladvancements.

 

Aswe have developed our technical abilities we have also inadvertently causedearthquakes and other seismic events. The simplest example of this is ourconventional and nuclear weapons capability where various conventionalexplosions and nuclear tests have registered on the ML scale (Richter Scale).Going so far as to produce upwards of magnitude 5 quakes for some undergroundnuclear tests in the late 1950’s and also possibly leading to further quakes inotherwise quiet seismic areas.

 

Howeverweapons are not the only way humans have induced earthquakes and other seismic events.These other inducements include fluid injection into the earth technologies,large earthworks and dam projects, mining and geothermal technologies. Here areseveral examples of how these technologies interact with seismicity:

 

Reservoirs- Themass of water in a reservoir alters the pressure in the rock below and throughfissures in the rocks, lubricates the faults on which they may sit, which cantrigger earthquakes (possibly extremely large magnitude quakes).Reservoir-induced seismic events can be relatively large compared to otherforms of induced seismicity.

 

Thefirst case of reservoir induced seismicity occurred in 1932 in Algeria’s OuedFodda Dam. There have been similar incidents including the 6.3 magnitude 1967Koynanagar Earthquake attributed to the Koyna Dam reservoir. During earlyconstruction of the Vajont Dam in Italy, there were seismic shocks recordedduring its initial fill. After a landslide almost certainly triggered by thisincreased seismicity filled the reservoir in 1963, the local tsunami in thelake behind the dam caused by the landslide overtopped the dam causing massivea 250m high megatsunami and subsequent flooding with around 2,000 deaths, itwas drained and consequently seismic activity has become almost completelynon-existent. On August 1, 1975, a magnitude 6.1 earthquake at Oroville,California, was attributed to seismicity from a massive earth-fill dam andreservoir recently constructed and filled there. In Zambia, Kariba Lake mayhave provoked similar effects.

 

Morerecently, the 2008 Sichuan earthquake, which caused approximately 68,000deaths, is another possible example of a large dam project inducing seismicity.An article in Science suggested that the construction and filling of theZipingpu Dam may have triggered the earthquake. However, researchers have beendenied access to seismological and geological data to examine the cause of thequake further. Some experts worry that because of this apparent link with the2008 Sichuan event the Three Gorges Dam in China may cause an increase in thefrequency and intensity of earthquakes.

 

Mining - Mining leaves voidsthat generally alter the balance of forces in the rock. These voids may collapseproducing seismic waves and in some cases reactivate existing faults causingminor or even large earthquakes. Natural cavern collapses that form sinkholeswould produce an essentially identical local seismic event. We have also beenresponsible for several volcanic inducements by drilling into seismicallyactive areas such as the Sidoarjo mud flow in Porong, Sidoarjo in East Java,Indonesia, which was caused by the company PT Lapindo Brantas sinking a naturalgas well and then over pressurising the system by fracking (see below).

 

Geothermal energy - Enhancedgeothermal systems (EGS), a new type of geothermal power technologies that donot require natural convective hydrothermal resources, are known to beassociated with induced seismicity. EGS involves pumping fluids at pressure toenhance or create permeability through the use of hydraulic fracturingtechniques. Induced seismicity in Basel led to suspension of its HDR project. Aseismic hazard evaluation was then conducted, which resulted in the total cancellationof the project in December 2009.

 

HydraulicFracturing -This is particularly pertinent at the current time with the non-debate (scientificallyat least) over fracking technologies in the United States (no it’s not aswearword from Battlestar Galactica).

 

Hydraulicfracturing, to give fracking its correct term, is a technology used to induceor propagate fractures in rocks by injecting pressurised fluids into those fracturesand thereby releasing held oil or gas allowing those fossil fuels to migrateeither to existing reservoirs or to come directly to the surface. Forsimplicity, using fracking technologies, we are rapidly increasing anddecreasing the pressure on natural faults within the earth’s crust to releasehydrocarbons and actually lubricating and extending these natural fracturezones.

 

Ifyou listened to opinion and editorial nonsense from the media you would assumethat fracking is a safe, wholesome technology that is helping America becomeless dependent on foreign oil so three cheers for the good ol’ US of A. Unfortunatelythis is not the case and factual studies have proved beyond a shadow of a doubtthat these fracking technologies can and have produced substantial earthquakesand increase seismicity wherever the technology is used.

 

Asa more pertinent warning; there are many fracking techniques currently beingundertaken close by or actually on the New Madrid Rift faulting system and, due to not understanding how that faultzone may be activated, we could conceivably activate and therefore induce amagnitude 8 earthquake in the region.

 

Thatis why it is vitally important that any person understands that opinion is notfact. To cut to the chase any media source that promotes fracking as a safetechnology are lying to the general public and are part of the scams and fraudsperpetrated by business interests that could and will likely lead to an extremeevent in more seismically active areas of the continental US.

 

 

Frackingcauses seismic activity as the pressures are released, this is a fact backed upby years of research and evidential support. Fracking also causes many other potentialenvironmental impacts including; contamination of ground water, risks to airquality, the migration of gases and hydraulic fracturing chemicals to thesurface, surface contamination from spills and flowback and the various healtheffects of these. For these reasons hydraulic fracturing has come under scrutinyinternationally, with some countries suspending or even outright banning itsuse.

 

Thatis not the case in the United States and for exactly the same reasons thatthere is a non-debate on human induced climate change. Namely this is becausecorporate America (and all large global producers affecting the environment) havefar more money to spend on disinformation campaigns than scientists have onpromoting their real and proven, and therefore, factual research.

 

Thusthese corporates spend huge amounts of cash seeding junk science,disinformation campaigns, pressure groups and opinion to the mass media andthis directly affects the vast majority of people’s views and opinions whobelieve that scientists are debating whether Human Induced Climate Change orHuman Induced Seismicity is actually a real thing. The reality is fardifferent.

 

Toput it bluntly 97% of scientists agree that the earth has been heating up overthe last 300 years due to the proliferation of carbon we humans have beenputting in to our atmosphere with a particularly strong spike in the last 50years or so. The other 3% of scientists, who are either on the fence or againstthese theories, are likely to be either financially supported by big businessor are dependent on them in some way for funding (it pains me to say that mostdissenters are geologists who rely on the energy companies for work).

 

Thisis the same for Human Induced Seismicity, seismographs are impossible to fakeso any earthquakes that are in the vicinity of these various fracking technologiesa link can be made using evidence support systems which is why there is nodebate in the scientific community about fracking causing earthquakes, the scienceis proven and the earthquakes caused cannot be faked, especially in areas withlittle to no known previous seismic activity.

 

Myadvice is to not listen to opinion but to seek out the actual scientificstudies for yourselves, if you don't understand them listen to someone thatdoes like a scientist and not a journalist, politician, religious leader orsomeone else in the pay of big business or who has something to gain by being adenier.

 

Rememberopinions are not facts. ‘Nullius in Verba' (“Take nobody's word forit”) the motto of the Royal Society.

 

 

 

This is a very interesting article by Julian Bulman, and it explains several aspects of the climate change non-debate.

 

Human ingenuity and technological advances have given us the ability to interact with our environment as no other animal or plant has been able to do through the whole of our planets 4.54 billion year evolution in such a small and inconsequential geological timescale. This includes the ability to produce significant earthquakes and other seismic activities using these technological advancements.

 

Aswe have developed our technical abilities we have also inadvertently causedearthquakes and other seismic events. The simplest example of this is ourconventional and nuclear weapons capability where various conventionalexplosions and nuclear tests have registered on the ML scale (Richter Scale).Going so far as to produce upwards of magnitude 5 quakes for some undergroundnuclear tests in the late 1950's and also possibly leading to further quakes inotherwise quiet seismic areas.

 

However weapons are not the only way humans have induced earthquakes and other seismic events.These other inducements include fluid injection into the earth technologies,large earthworks and dam projects, mining and geothermal technologies. Here are several examples of how these technologies interact with seismicity:

 

Reservoirs- The mass of water in a reservoir alters the pressure in the rock below and through fissures in the rocks, lubricates the faults on which they may sit, which can trigger earthquakes (possibly extremely large magnitude quakes).Reservoir-induced seismic events can be relatively large compared to other forms of induced seismicity.

 

The first case of reservoir induced seismicity occurred in 1932 in Algeria's Oued Fodda Dam. There have been similar incidents including the 6.3 magnitude 1967 Koynanagar Earthquake attributed to the Koyna Dam reservoir. During early construction of the Vajont Dam in Italy, there were seismic shocks recorded during its initial fill. After a landslide almost certainly triggered by this increased seismicity filled the reservoir in 1963, the local tsunami in thelake behind the dam caused by the landslide overtopped the dam causing a massive 250m high megatsunami and subsequent flooding with around 2,000 deaths, it was drained and consequently seismic activity has become almost completely non-existent. On August 1, 1975, a magnitude 6.1 earthquake at Oroville,California, was attributed to seismicity from a massive earth-fill dam andreservoir recently constructed and filled there. In Zambia, Kariba Lake may have provoked similar effects.

 

Morerecently, the 2008 Sichuan earthquake, which caused approximately 68,000deaths, is another possible example of a large dam project inducing seismicity.An article in Science suggested that the construction and filling of theZipingpu Dam may have triggered the earthquake. However, researchers have beendenied access to seismological and geological data to examine the cause of thequake further. Some experts worry that because of this apparent link with the2008 Sichuan event the Three Gorges Dam in China may cause an increase in thefrequency and intensity of earthquakes.

 

Mining - Mining leaves voidsthat generally alter the balance of forces in the rock. These voids may collapseproducing seismic waves and in some cases reactivate existing faults causingminor or even large earthquakes. Natural cavern collapses that form sinkholeswould produce an essentially identical local seismic event. We have also beenresponsible for several volcanic inducements by drilling into seismicallyactive areas such as the Sidoarjo mud flow in Porong, Sidoarjo in East Java,Indonesia, which was caused by the company PT Lapindo Brantas sinking a naturalgas well and then over pressurising the system by fracking (see below).

 

Geothermal energy - Enhanced geothermal systems (EGS), a new type of geothermal power technologies that do not require natural convective hydrothermal resources, are known to be associated with induced seismicity. EGS involves pumping fluids at pressure to enhance or create permeability through the use of hydraulic fracturing techniques. Induced seismicity in Basel led to suspension of its HDR project. A seismic hazard evaluation was then conducted, which resulted in the total cancellation of the project in December 2009.

 

Hydraulic Fracturing -This is particularly pertinent at the current time with the non-debate (scientifically at least) over fracking technologies in the United States (no it's not a swearword from Battlestar Galactica).

 

Hydraulic Fracturing, to give fracking its correct term, is a technology used to induce or propagate fractures in rocks by injecting pressurised fluids into those fractures and thereby releasing held oil or gas allowing those fossil fuels to migrate either to existing reservoirs or to come directly to the surface. For simplicity, using fracking technologies, we are rapidly increasing and decreasing the pressure on natural faults within the earth's crust to release hydrocarbons and actually lubricating and extending these natural fracture zones.

 

Ifyou listened to opinion and editorial nonsense from the media you would assumethat fracking is a safe, wholesome technology that is helping America becomeless dependent on foreign oil so three cheers for the good ol' US of A. Unfortunatelythis is not the case and factual studies have proved beyond a shadow of a doubtthat these fracking technologies can and have produced substantial earthquakesand increase seismicity wherever the technology is used.

 

As a more pertinent warning; there are many fracking techniques currently being undertaken close by or actually on the New Madrid Rift faulting system and, due to not understanding how that faultzone may be activated, we could conceivably activate and therefore induce a magnitude 8 earthquake in the region.

 

That is why it is vitally important that any person understands that opinion is not fact. To cut to the chase any media source that promotes fracking as a safe technology are lying to the general public and are part of the scams and frauds perpetrated by business interests that could and will likely lead to an extreme event in more seismically active areas of the continental US.

 

 

 

Fracking causes seismic activity as the pressures are released, this is a fact backed up by years of research and evidential support. Fracking also causes many other potential environmental impacts including; contamination of ground water, risks to air quality, the migration of gases and hydraulic fracturing chemicals to the surface, surface contamination from spills and flowback and the various health effects of these. For these reasons hydraulic fracturing has come under scrutiny internationally, with some countries suspending or even outright banning its use.

 

That is not the case in the United States and for exactly the same reasons that there is a non-debate on human induced climate change. Namely this is because corporate America (and all large global producers affecting the environment) have far more money to spend on disinformation campaigns than scientists have on promoting their real and proven, and therefore, factual research.

 

Thus these corporates spend huge amounts of cash seeding junk science,disinformation campaigns, pressure groups and opinion to the mass media and this directly affects the vast majority of people's views and opinions who believe that scientists are debating whether Human Induced Climate Change or Human Induced Seismicity is actually a real thing. The reality is far different.

 

To put it bluntly 97% of scientists agree that the earth has been heating up over the last 300 years due to the proliferation of carbon we humans have been putting in to our atmosphere with a particularly strong spike in the last 50 years or so. The other 3% of scientists, who are either on the fence or against these theories, are likely to be either financially supported by big business or are dependent on them in some way for funding (it pains me to say that most dissenters are geologists who rely on the energy companies for work).

 

This is the same for Human Induced Seismicity, seismographs are impossible to fake so any earthquakes that are in the vicinity of these various fracking technologies a link can be made using evidence support systems which is why there is no debate in the scientific community about fracking causing earthquakes, the science is proven and the earthquakes caused cannot be faked, especially in areas with little to no known previous seismic activity.

 

My advice is to not listen to opinion but to seek out the actual scientific studies for yourselves, if you don't understand them listen to someone that does like a scientist and not a journalist, politician, religious leader or someone else in the pay of big business or who has something to gain by being a denier.

 

Remember opinions are not facts. 'Nullius in Verba' ("Take nobody's word for it") the motto of the Royal Society.

[Ophiolite]

I would be curious to learn more about how they can put a decent and sturdy casing in place when drilling horizontally and using a slurry to shatter the surrounding areas of the bore hole (since that's what breaks open the gases). One would think a separate hole would need to be drilled and filled at a higher depth than the extraction hole to offer good enough protection to the surrounding area.

Practically all oil and gas wells contain multiple strings of casing. Typically the first string is there to prevent collapse of poorly consolidated surface sediments. The next string may be placed to protect aquifers. subsequent strings seal of troublesome formations: mobile salt' date=' overpressures, vuggy limestones, hydrophilic shales. Only the last string, the production string, penetrates the reservoir. So, in a typical well there are mutliple strings of casing and associated cement to provide isolation and protection.

 

Casing and cementing applies only locally to the bore. In a traditional reservoir, hydrocarbons have been held in place for millions of years by a tight capping geological layer, which is not the case in shale.

This turns out not to be the case. Most productive shales lie beneath unproductive shales, or other zero/low permeability rocks, such as evaporites.

 

I'm fully confident that fracturing, which is conducted from kilometres distance, without sight, in an imprecisely known terrain, will sometimes extend beyond the compact rock into permeable terrain, letting hydrocarbons leak.

I am sure that this may occur. However, while we have instances of contamination of aquifers by hydrocarbons from completely different sources, we don't seem to have instances where it occurs as you are proposing. I stand ready to be corrected on this point by reasonable evidence.

 

Even if oil companies were Nature-minded (History shows, err, exceptions) errors do happen, and they are logically more probable - understand, more frequent - with shale oil.

To justify that opinion you would need to submit more facts than you have to date.

 

The notion that the "fracking itself" is not usually the major problem seems a distinction without a difference. If true - and it will be years before we know - so what?

If we wish to prevent problems do you not think it wise we determine the root cause? If, as I suggest, the primary issue is of insufficient attention to casing and cementing design and implmentation rather than the fraking process itself then we really need to know that: it is a central distinction.

 

that this whole operation was launched without due diligence, without the slightest consideration for the integrity of the aquifers or the welfare of the residents or the health of the environment in the region.

Operators are obliged by law and by strong desire to avoid lawsuits to consider the integrity of aquifers. Where is your evidence that the operators did not employ due diligence?

 

 

Even with sufficient cement and casing works' date=' I still would not suspect this work to be environmentally friendly. The sheer number of boring holes and the vast amount of fluid used in the entirety of these operations is going somewhere. It doesnt just dissapear, and it is challenging to treat.[/quote']

I don't see how the number of holes is any kind of issue; perhaps you can expand on that. The disposal of fracking fluid is an environmental issue. the bulk of the fluid is returned to surface as production begins. The fluid does contain several components of environmental concern. I cannot say how effectively this issue is being addressed. However, that is not the thrust of this thread.

 

And yes, in many cases, cement jobs may be poor or casing may be damaged, which would be the ultimate issue, however, if it werent for an interest in fracturing, there wouldnt be faulty cement jobs and casing to begin with. It is inevitable that human error will lead to cement and casing issues.

So let's stop driving cars, watching TV and flying to Cancun for holidays.

[iDevonian]

I don't see how the number of holes is any kind of issue; perhaps you can expand on that. The disposal of fracking fluid is an environmental issue. the bulk of the fluid is returned to surface as production begins. The fluid does contain several components of environmental concern. I cannot say how effectively this issue is being addressed. However, that is not the thrust of this thread.

 

 

So let's stop driving cars, watching TV and flying to Cancun for holidays.

 

The number of holes equates to the number of operations, the number of events in which human error can occur with regards to things like cement and casing, spills, leaks, seeps, blowouts, and typical accidents that may be present on rig locations (and yes, they all do exist, as we all know. Not a day passes by in which rig hands arent discussing safety matters and continual accidents that occur around the nation).

 

We are also talking about things like deforestation, clearing paths through forests for pipelines (and erosion from this), spills and accidents with vehicles transporting resources to and fro, on Site spills, accidents with pressurized hozes used for cement jobs...rigs even burn down from time to time (it is all too common).

 

And as for your second comment. I didnt say we should stop driving cars and watching tv. I just said, with these kinds of operations, accidents happen. These operations are far from environmentally friendly. That is all I am saying. If these operations did not exist, then we wouldnt have to worry about contaminating the ground water, and we realistically wouldnt even be having this conversation right now.

 

Even something as simple as a typical Sonoco gas station, in many cases results in ground water and environmental contamination release. If something as simple as a basic gas station is likely to have a release of contaminants to the earth, there is really no doubt in my mind (or anyone elses for that matter) that these operations do in fact harm the environment.

 

However, just because sonoco gas stations have oil spills, it is subjective to claim that because of this, we should stop using gas stations. Likewise, just because rig operations may damage the environment, it doesnt necessarily mean we should get rid of...what is it...30% of US gas based electrical production?

 

Its all subjective. I am all for using a gasoline car and burning gas powered lights. But theres no way I would let one of those rigs sit near my water table.

Edited November 6, 2012 by iDevonian

[overtone]

If we wish to prevent problems do you not think it wise we determine the root cause? If, as I suggest, the primary issue is of insufficient attention to casing and cementing design and implmentation rather than the fraking process itself then we really need to know that: it is a central distinction.

Far from being central, the distinction is almost irrelevant.

 

Or to put it another way: OK, we'll only put a moratorium on fracking wells that employ such casings and cement work.

 

that this whole operation was launched without due diligence, without the slightest consideration for the integrity of the aquifers or the welfare of the residents or the health of the environment in the region.

 

Operators are obliged by law and by strong desire to avoid lawsuits to consider the integrity of aquifers. Where is your evidence that the operators did not employ due diligence?

The evidence was as given by the gas companies: the fact that they did not acquire baseline data on the aquifers they intended to put at risk; that they themselves state that they intend to collect baseline data on wells etc in the future, for the first time.

 

That is proof that due diligence was not employed in sinking earlier wells. And they have been using such lack of information to defend themselves - claiming, for example, that no one knows whether contaminated wells now generating bad publicity were contaminated before the fracking. The fact that they have no data bearing on that question, data that would exonerate them quickly and easily, is damning.

 

So let's stop driving cars, watching TV and flying to Cancun for holidays.

Better options than fouling our aquifers.

[Ophiolite]

Far from being central, the distinction is almost irrelevant.

 

Or to put it another way: OK, we'll only put a moratorium on fracking wells that employ such casings and cement work.

All oil and gas wells employ casing and cement for the reasons previously noted.

 

I am bemused by your belief that diagnosis is not a prerequisite of treatment. It is possible to adopt a Luddite position and oppose any technology that carries with it risk (i.e. all technology). If you wish to have the benefits of technology - and your use of the internet suggests you do - then you need to ensure that the technology is applied in as safe a manner as practical. That means the mechanisms of any undesirable outcomes are identified and mitigated. Therefore the cause of any aquifer contamination must be identified.

[overtone]

I am bemused by your belief that diagnosis is not a prerequisite of treatment.

No doubt you would be even more bemused if such an extraordinary belief actually resembled anything of mine.

It is possible to adopt a Luddite position and oppose any technology that carries with it risk (i.e. all technology).

It is not possible to discover thread relevance in such a left-field comment' date=' however.

Therefore the cause of any aquifer contamination must be identified.

And of course - meanwhile, as well as afterwards - prevented.

If you wish to have the benefits of technology - and your use of the internet suggests you do - then you need to ensure that the technology is applied in as safe a manner as practical.

It is not practical to foul large aquifers in any cause other than truly emergency survival.

 

The cause of avoiding the inconveniences of advanced technology, such as solar power in various forms, is not one of those.

[Kalopin]

With new forms of alternative energy sources [regeneration, kinetic along with wind, solar, hydro, and geo-thermal] fracking is already obsolete. These people care very little for the environment and only care about profits! You may say that it can be done safely, but it is not. If you argue for drilling out any large amount from underneath your feet, then you do not understand "Earth Sciences"!

Edited November 10, 2012 by Kalopin

[overtone]

An example of handling the cement casing problem - without considering the fracture migration problem, the geological surprise communication problem, etc:

 

http://www.midwestenergynews.com/2012/10/02/safety-of-shale-gas-wells-up-to-states-and-the-cement-job/

 

- - - Ohio’s “best practice” standard calls for visual evidence that cement has reached from the bottom of the initial pipe string to the surface. “We want to see a number of barrels of good-quality dense slurry coming out before we consider the job complete,” Kell said. - - -

- - - -

“For every single well permit in Ohio, we design the well casing case by case,” Kell said. “We expect a very agile, flexible approach to compliance, and we have inspectors out there to ensure it’s done right. “Our role is to witness every one of those surface casing cement jobs,” for example, he added. “It’s more than that. We are looking at the overall job performance. We’re looking at the density of that cement. We’re looking at pumping rates. We’re looking at lift pressures and other things out on the job to see whether that cement operation is performed according with the design standards.

 

“If they have not demonstrated protection of groundwater and USDW, they must plug the well,” Kell said. “You’re done.”

 

 

 

[zapatos]

It is not practical to foul large aquifers in any cause other than truly emergency survival.

To what extent are large aquifers fouled (or potentially fouled) by fracking? Where I live we get our drinking water from the Missouri River and from a smaller river which does not have a reputation for being particularly clean. Our drinking water on the other hand is first rate.

 

Is the potential damage from fracking something that could make an aquifer unusable, or is the issue strictly economical, in that if the water is fouled it will have to be cleaned prior to use?

 

With new forms of alternative energy sources [regeneration, kinetic along with wind, solar, hydro, and geo-thermal] fracking is already obsolete. These people care very little for the environment and only care about profits! You may say that it can be done safely, but it is not. If you argue for drilling out any large amount from underneath your feet, then you do not understand "Earth Sciences"!

Can you back that up please? I find it hard to believe that the alternative energy sources you mention could come anywhere near replacing natural gas anytime soon.

[Kalopin]

To what extent are large aquifers fouled (or potentially fouled) by fracking? Where I live we get our drinking water from the Missouri River and from a smaller river which does not have a reputation for being particularly clean. Our drinking water on the other hand is first rate.

 

Is the potential damage from fracking something that could make an aquifer unusable, or is the issue strictly economical, in that if the water is fouled it will have to be cleaned prior to use?

 

 

Can you back that up please? I find it hard to believe that the alternative energy sources you mention could come anywhere near replacing natural gas anytime soon.

 

The fossil fuel industry has done an excellent job installing blinders on much of the general public. Tesla wanted electricity to be free, but Edison, Westinghouse, G.E., etc... all wanted to find a way to make money, and they did.

 

It is not difficult for me to imagine everyone having their own personal energy. Every house and building covered in collector cells, several wind turbines, using hydro and geothermal more, but it is my belief that regeneration and kinetic energy sources will be another excellent alternative source.

 

There is NO doubt that other sources MUST be used. Commercials brag about having one hundred years supply of natural gas, or "clean coal", or "safe and efficient nuclear power". That is ridiculous. What are they saying to their great grandkids? You deal with it? Oil, coal, and nuclear have done enough. It is time to open your eyes, realize- oil, coal, and nuclear WILL NOT be the choice for a decent future.

 

 

My real point- Anthropogenic aquifer contamination should not even be a question, and even if they did find a way to safely extract, it would be selfish and ignorant to use up natural resources when alternatives are available. It should be set up and stored for a future when these sources might have to be used, ya' think?

Edited November 10, 2012 by Kalopin

[zapatos]

The fossil fuel industry has done an excellent job installing blinders on much of the general public. Tesla wanted electricity to be free, but Edison, Westinghouse, G.E., etc... all wanted to find a way to make money, and they did.

 

It is not difficult for me to imagine everyone having their own personal energy. Every house and building covered in collector cells, several wind turbines, using hydro and geothermal more, but it is my belief that regeneration and kinetic energy sources will be another excellent alternative source.

 

There is NO doubt that other sources MUST be used. Commercials brag about having one hundred years supply of natural gas, or "clean coal", or "safe and efficient nuclear power". That is ridiculous. What are they saying to their great grandkids? You deal with it? Oil, coal, and nuclear have done enough. It is time to open your eyes, realize- oil, coal, and nuclear WILL NOT be the choice for a decent future.

 

 

My real point- Anthropogenic aquifer contamination should not even be a question, and even if they did find a way to safely extract, it would be selfish and ignorant to use up natural resources when alternatives are available. It should be set up and stored for a future when these sources might have to be used, ya' think?

 

When I asked you to back up your statement that "With new forms of alternative energy sources [regeneration, kinetic along with wind, solar, hydro, and geo-thermal] fracking is already obsolete", what I was looking for was something along the lines of an estimate of current energy capacity of the alternatives you mentioned versus the current energy capacity of natural gas.

 

Do you have any evidence that suggests the alternatives you mention can replace natural gas right now or in the very near future?

[Kalopin]

When I asked you to back up your statement that "With new forms of alternative energy sources [regeneration, kinetic along with wind, solar, hydro, and geo-thermal] fracking is already obsolete", what I was looking for was something along the lines of an estimate of current energy capacity of the alternatives you mentioned versus the current energy capacity of natural gas.

 

Do you have any evidence that suggests the alternatives you mention can replace natural gas right now or in the very near future?

 

Shouldn't there be plenty of studies? I may not be the expert for you on calculations, but my point is that: We have no choice. All the science is already in: We have peaked on oil supplies, we continue to destroy air and water quality, the human race is becoming too greedy for this planet. It is all a case of "resource mis-management".

 

It is possible to run on hydro-electric alone. There is just no infrastructure and not enough concern or interest. Will it be true again- "necessity is the mother of invention". Do you want to wait until it all runs out?

[zapatos]

Shouldn't there be plenty of studies? I may not be the expert for you on calculations, but my point is that: We have no choice. All the science is already in: We have peaked on oil supplies, we continue to destroy air and water quality, the human race is becoming too greedy for this planet. It is all a case of "resource mis-management".

 

It is possible to run on hydro-electric alone. There is just no infrastructure and not enough concern or interest. Will it be true again- "necessity is the mother of invention". Do you want to wait until it all runs out?

I'll take that as a 'no'.

[iDevonian]

There is plenty of evidence that alternatives can and will replace fossil fuels in the near future.

 

By the nature of what fossil fuels are, it will not be long before we have no option but to move on.

Edited November 10, 2012 by iDevonian