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couchmaster
climber
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From PSP also PP's link, quote: "Was your California orange irrigated with wastewater from oil wells? Quite possibly yes. Under a 20-year-old water recycling program, wastewater that is generated as a byproduct from oil extraction is treated and sold to some 90 Southern California landowners—including one with certified organic operations—which use it to grow crops such as citrus, almonds, apples, peaches, grapes, and blueberries sold in major grocery chains around the country." XX!@!!!!
Anyway, back to fracking. Mad Dog has it correct about Coal upthread. Coal burned to make electricity produces 71 percent of all of the CO2 the US adds to the world right now. Fracking and natural gas usage has been significantly better for the worlds environment than coal. If you could cut fracking to zero, you'd be screwing up the envronment real bad as coal would be the replacement fuel. Until now. MIT appears to have some good news on coal right here: https://stream.org/mit-finds-way-make-coal-twice-green/
I don't know what "twice as green" means. Is that like a laundry detergent promising to make your shirts "Whiter than white". What is that? When you follow the link you get a more sensible statement: ..."researchers at MIT have come up with a plan that could contribute to that effort by making it possible to generate electricity from coal with much greater efficiency — possibly reaching as much as twice the fuel-to-electricity efficiency of today’s conventional coal plants. This would mean, all things being equal, a 50 percent reduction in carbon dioxide emissions for a given amount of power produced."
Great news. We should be able to sell the technology to China and other heavy polluters if it's a viable thing. Certainly will get our nasty coal emissions down as well.
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Lorenzo
Trad climber
Portland Oregon
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Can anybody point to a good outcome with groundwater aguifers after and area has been fracked?
Ever?
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BASE104
Social climber
An Oil Field
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High pressure toxic fluid injection plus imperfect knowledge of cracks and weaknesses in the rock layers between the injection site and the water table, and the imperfect ability to engineer systems according to design over a large number of iterations, leaves a lot of room for "oops" moments. It seems quite a bit of hubris to assume we can control all the variables well enough, to not just mitigate, but to "prevent" accidents.
Man. You guys just have no concept of the depth of these wells and what happens during a fracking operation. I'll try to summarize it.
First, if you drive up to a well head, you will have no idea if it was fracked or not, or if it is a vertical or horizontal well. The vast majority of these wells are well over 8000 feet deep. The notion that you are somehow exploding the ground beneath your feet is just hogwash.
First, there is no real difference between a vertical fracked well and a horizontal fracked well, other than volume injected. In most areas, all wells need to be fracked, and have been for 75 years or something like that.
You drill down vertically until you are about 500 feet above your target interval. Then you rapidly build a turn from vertical to horizontal, and if you do it right, you "land" the wellbore right in the target horizon, which is very specific. Above that inverval is thousands and thousands of feet of normal shale, sandstones, and limestones. The porous sandstones and limestones are full of saltwater or hydrocarbons. The horizontal wells target a very specific layer of rock. For this discussion I will confine the discussion to shales.
Shales are the most common type of sedimentary rock. In most sedimentary basins, 90% of the rock you drill through is shale. So why don't you frack all of that shale? Because it doesn't contain hydrocarbons first, and second because the shales are clay rich and ductile. You can pump into that stuff forever and never be able to frack it.
The target shales are generally the specific organic carbon rich shales which source all of the oil and gas in the entire basin, and their thickness varies from 50 to 400 or so feet thick. They have to not only contain hydrocarbons, but they must also be brittle. That generally means that they are quartz rich. Just like a sandstone, except the grain size is far smaller. If it isn't brittle, it won't frack. You can pump into it until the cows come home and it won't fracture.
So understand that the targets are specific zones, and only contain recoverable hydrocarbons if they are deep enough to be thermally mature. Typically over 10,000 feet deep. You still have to carefully steer the bit so that the wellbore stays within a brittle zone, which is typically a quarter or so as thick as the entire target shale (which I already said is usually a few hundred feet thick).
The fractures do not extend very far above or below the brittle target interval. You simply can't fracture those overlying shales, even if you tried. The federal government actually experimented with using nuclear weapons to frack a few wells (one of which is near Rifle, CO). The nukes didn't work.
Why do you drill horizontal wells? A: Because the zone has very low permeability, and a single vertical would barely produce. With horizontals, you selectively perforate your casing every hundred feet or so along the length of the lateral, which is usually 5000 to 10,000 feet long. It is like having 60 vertical wells, with each perforation being the equivalent of a single vertical well.
I've been out on quite a few frack jobs and it works like this: You have portable tanks containing millions of gallons of water, and sand trucks containing hundreds of thousands of pounds of sand. You have already perforated the production liner before the frack boys show up. You isolate each stage along the horizontal, and each stage is like a separate frack. The goal being to not only induce fractures and improve permeability, but to displace the proppant (typically a very particular type of sand, or ceramic beads). The frack stage is successful if you are able to displace all of the proppant into the stage. Out of 60 or so stages, some of them were not steered properly and for some reason or other, you can't fracture a particular stage. The failure to inject the sand is usually because that perforated cluster is outside of the targeted brittle layer. If you don't properly steer the horizontal, it simply won't fracture. If it has too much clay, it won't fracture.
If you rupture your casing, you will immediately see a spike in the annular pressure behind that casing string, and you stop right there. When that happens, which isn't common. You just lost the well. Casing integrity is very important, and horizontals have an additional 1 or 2 strings compared to a vertical.
Anyway, from a seat in the command trailer, you get to see all of the pressure readings. Sensor gauges are attached to the annulus of each casing string. They begin pumping, and you watch the pressure climb. At a certain point you will see the pressure fall, and this means that the formation just began to fracture. You then pump the sand and water slurry into that casing liner at a high rate until you have displaced all of the sand for that stage.
Then you release and reset your packers and move back and isolate the next cluster of perforations and frack that stage. You repeat this until each stage has been fracked. The success or failure is pretty much known right away. How many stages were you successfully able to displace the proppant into...
After you are finished with the last stage, you rig down the frack pump trucks and immediately open the well and allow the water to flow back, typically under its own pressure.
I spent a year as an in house consulting geologist for one of the most prolific fracking companies, although the area I was working didn't require fracks.
To see how much volume of the target shale you have successfully fractured, an important point in frack design, you use microseismic technology now and then. I've seen a number of these datasets. What they are is similar to active seismic. You lay out an array of geophones and record the noise of the fractures propagating through the rock. It is then processed through supercomputers and you get a nice 3D picture of where each fracture went. I've never seen a fracture get more than 100 feet out of zone. Again. That is because these targeted carbon rich brittle shales will fracture, but normal clay rich shales above and below are too ductile to fracture.
The microseismic sets are pretty cool. We had a conference room where you could put on a 3D virtual headset and wave your hands around the dataset with the reservoir engineers. The objective is to fracture as much of that brittle shale as possible. Despite the huge amounts of water and sand, a lateral normally fractures only a few hundred feet laterally, so it takes a lot of horizontals to effectively drain the reservoir and recover the hydrocarbons (typically gas, but not always). Anyway, you could see the lateral and little dots around the wellbore showing each fracture.
You don't do this on every well. It is a reservoir engineering tool only.
The company I worked for drilled fresh water montitoring wells before drilling any horizontal fracked wells, just to cover their ass from all of the baloney being published. They had an entire groundwater division.
They never had a problem, but there were a few spills, almost always either water or saltwater from the reservoir. This was a handful out of tens of thousands of wells.
On groundwater: Fresh water is normally super shallow in terms of oil and gas drilling. Rarely does it exceed 500 feet in depth, and at least in the Appalachian Basin, commonly contained methane from shallow coal seams. Hell, there is a town in Pennsylvanian called Burning Springs if that gives you an idea.
In my area, the mid-continent, the usual shale target is the Woodford Shale. A very specific ealy Mississippian carbon rich shale. The Woodford sourced almost all of the oil and gas in conventional reservoirs in Oklahoma, Kansas, and the Texas Panhandle. It is high in organic carbon, and has been buried deep enough to be thermally mature enough to generate both oil and natural gas.
The Woodfod has been drilled up in the Arkoma Basin in the SE part of the state. I'm not aware of any groundwater contamination, period, out of tens of thousands of fracked wells.
The Woodford has also been fracked in the eastern Anadarko Basin, and I'm unaware of any problems. Nothing made the newspaper, anyway. I've been to some very expensive seminars on the Woodford and understand it well. Nowadays, they are recycling the flowback frack water and re-using it. It is a nice and tidy operation.
They have found so much natural gas that there will be a supply glut throughout my lifetime. It takes 8 horizontals to drain a single square mile section, and there are thousands of sections with only a single well on them, to hold the leases by production. There are 7 increased density wells per section to be drilled some day when natural gas prices recover.
These days, companies have been changing their completions and limit fugitive methane emissions through "green" completions, where they test the well down the sales line instead of venting or flaring gas during the completion.
In the Anadarko Basin, you have to drill through the Springer Sandstone series on the way down to the normally pressured Woodford. The Springer is often over pressured, and if you aren't careful, you can blow out. A couple of wells have blown out and burned the derricks to the ground from stray Springer sands that weren't expected.
There is a lot more science than I can express in this format. You guys would really need to come hang out with me and allow me to walk you through the gas fields on my computer system. After a couple of weeks, you would learn the very basics about how oil and gas accumulate and are recovered.
Ed works for Livermore. They designed most of our nukes. Even if he was allowed to discuss it here, it would be hard to teach the basics of what he does. I have the same problem, but worse. I have to deal with reams of bullshit that people have been making up for the past ten years.
A reasonably intelligent person would find it almost impossible to learn the actual truth about how fracking works just from using Google. I see big publications getting it wrong. Like the New York Times.
It is actually a pretty simple operation, but it is pretty much hopeless. I can't get through to you guys because there is so much garbage information out there. Journalists never get it right, even good ones.
So I forgive your ignorance. It is almost impossible to find out the truth about how fracking works, how safe it is, and all that. So I toss up my hands and give up.
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BASE104
Social climber
An Oil Field
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Can anybody point to a good outcome with groundwater aguifers after and area has been fracked?
That one is easy. Everywhere. Groundwater contamination is extremely rare in modern wells. Groundwater pollution normally takes place in old oil fields that were drilled pre-1960. They didn't even case off the fresh water.
You would go to prison if you did that in Oklahoma these days, or at the least pay a huge fine.
The thing that companies fear most is a landowner lawsuit. They can cost millions if you screw up an aquifer. Protecting fresh water is a very simple and cheap part of drilling any modern well.
Show me a place where there is widespread contamination from modern fracked wells. And no baloney youtube videos.
Most groundwater pollution from oil and gas activities is from saltwater getting into the fresh water. Gas contamination of an aquifer is really rare. I'm aware of 2 modern cases in Oklahoma. Saltwater is by far the most common pollutant.
I posted above that one company I consulted for drilled freshwater monitoring wells before any fracking operations just to keep the crazies away. They could drill them for less than 20 grand, which is nothing when your well cost is over 5 million per well. Naturally occurring methane in groundwater is actually reasonably common in hydrocarbon basins. I can show you oil and gas at 300 feet in two areas that I've worked. 300 feet is crazy shallow for oil and gas, which is usually found much deeper, miles beneath the fresh water, which is shallow.
Deeper zones commonly contain water, but it is naturally occurring saltwater. Hitting saltwater instead of oil is the most common type of dry hole.
JFailing wrote a pretty good post above.
I'm getting ready to recomplete an old gas well. The gas zone is 15 feet thick, 4500 feet deep, and depleted. There are 2 oil zones above it that the Operator missed. One is 8 feet thick and one is 5 feet thick. Above those two zones are about 100 porous zones, all of which contain saltwater.
You selectively perforate your cemented casing right at the producing zone. This prevents the ocean of saltwater from getting into your well and ruining it, forcing you to plug and abandon it.
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Invisiblehand
Mountain climber
Casper, Wy
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Petroleum Engineer here. (I know I'm going to get downvoted to hell)
The techniques used in hydraulic fracturing (fracking) are designed to mitigate the communication of frac water (which may or may not contain certain chemicals depending on the formation you're attempting to fracture)
Fracturing is generally only done in formations with significant depth to make the emergence of frac water into formations with potable water unlikely. It is also usually done in formations with so called 'cap rocks' above and below which are more or less impermeable to fluids due to their dense structure. We are also able to tell via math and science if any of our frac water has migrated between formations due to changes in pressure and flowrate as we monitor frac jobs.
Now, there are chemical contamination that can occur, but it's usually a case of a faulty casing / cement job in the vertical (read shallow) portion of the well. This is what really needs to be avoided, but the same things happen in wells that aren't even fractured.
I'm an engineer, but I'm also a climber, and a lover of nature. I don't want to see contamination of our vital resources more than any of you, but I also know that when done correctly, the process of hydraulic fracturing is safe.
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BASE104
Social climber
An Oil Field
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To give you an idea, the Woodford Shale, the main shale gas target in the mid-continent is colored yellow on this section of a Dual Induction Laterlog.
It is less than 50 feet thick in this well, and is at a depth of 3900 feet.
Overlaying it is the Caney Shale, which is too clay rich to frack. Above that and not shown is the Pennsylvanian section, which is mainly sequences of sandstone and shale. Every layer has a name. Above the Caney is the Bartlesville Sandstone (saltwater bearing), Red Fork Sandstone (saltwater bearing), Upper and Lower Skinner (also "wet"), Prue Sandstone (wet) and then the Cleveland and shallower Virgilian zones, each of which has a name and many of which produce here and there. All of the overlying carboniferous zones require a frack on vertical wells, and have been fracked for decades.
You can drill a ten thousand foot well, passing through ductile shales, saltwater bearing sandstones, evaporate sequences, and other zones for the overlying 3800 feet.
And this is an absurdly shallow well.
I look at the squiggly lines all day long, every day. I don't even see the curves anymore. I see shale, sandstone, limestone, whether one or more has hydrocarbons, whether it is recoverable, etc.
The notion that Fracking is destroying the groundwater is a bunch of hogwash. Yes, it is an industrial process. Yes, accidents can happen. Rarely is there significant, if any, contamination.
When this all started, I expected some flack, because a frack involves a ton of trucking of sand and water to the location. I never thought that fracking itself would be controversial. We are very familiar with the process. Most of the wells I've drilled in my career were fracked. Plain old vertical oil and gas wells.
Now and then I get good enough permeability to get by without a frack, but they increase permeability in the target rock and a 5 bbl/day well might make 200 bopd if fracked. It just depends on the rock and the area.
So when people talk of injecting into the "ground," this is a bit of a misnomer. Yes, they are beneath the surface, but they are at great depth and a typical target is less than 20 feet thick. The zones are even thinner in Kansas. You might drill a well a mile deep looking for oil in a 3 foot thick Marmaton or Cherokee zone. The overlying zones are filled with saltwater. They are cased and cemented off. You perforate the casing right at your zone, so you can isolate it and just produce oil. These are a little more complicated than a hole in the ground.
People don't realize how big a producer the U.S. is. We are one of the top oil and gas producing countries in the world. The problem is that we are 5% of the world population and use 25% of the oil.
And boy do we waste it. Bottled water costs an order of magnitude more than oil right now. As long as it is cheap, alternatives will fail. They can't compete with cheap oil.
I've always been in favor of a carbon tax. It is the only way to make alternatives economically competitive.
Look at Iran. They are fairly mature, meaning most of their oil has been found. They also sit on some of the biggest gas fields on Earth, with no market. To make money from exports, they have begun using methane as an alternative to oil, and they are now the biggest users of methane as a transportation fuel on the planet. We would do well to copy that, because we are swimming in cheap gas, and will be throughout my lifetime.
Use it as a bridge fuel until something better shows up. Natural gas vehicles are much cleaner and cheaper to operate. The problem is that you only get half as much distance on a tank compared to oil. Since little pipeline distribution is present, filling stations are rare. That is why you see fleet vehicles that don't stray far using natural gas as a fuel.
If we just converted our trucking to natural gas, it would go far towards cleaning things up. It is the cleanest burning fossil fuel by far. There is so much remaining shale gas that it would blow your mind. Again, you would have to come hang out with me and let me show you how it works. Most of the shale accumulations have been figured out by now, and their boundaries are known. The increased density wells are just sitting there waiting to be drilled, and there are thousands of them.
Right now, all natual gas drilling has pretty much halted. It isn't worth much. It forced a change in focus to liquids, and then we found too much of that. So now prices are in the toilet.
The oil business is incredibly cyclic. A geologist buddy of mine now makes most of his money playing natural gas options, and does well. It is too cheap to drill for, though.
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tuolumne_tradster
Trad climber
Leading Edge of North American Plate
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FYI...
Impact to Underground Sources of Drinking Water and Domestic
Wells from Production Well Stimulation and Completion Practices in
the Pavillion, Wyoming, Field
Dominic C. DiGiulio*,† and Robert B. Jackson†,‡,§
†Department of Earth System Science, ‡Woods Institute for the Environment, and §Precourt Institute for Energy, Stanford University,
Stanford, California 94305, United States
DOI: 10.1021/acs.est.5b04970
ABSTRACT: A comprehensive analysis of all publicly available
data and reports was conducted to evaluate impact to
Underground Sources of Drinking Water (USDWs) as a result
of acid stimulation and hydraulic fracturing in the Pavillion, WY,
Field. Although injection of stimulation fluids into USDWs in the
Pavillion Field was documented by EPA, potential impact to
USDWs at the depths of stimulation as a result of this activity
was not previously evaluated. Concentrations of major ions in
produced water samples outside expected levels in the Wind
River Formation, leakoff of stimulation fluids into formation
media, and likely loss of zonal isolation during stimulation at
several production wells, indicates that impact to USDWs has
occurred. Detection of organic compounds used for well
stimulation in samples from two monitoring wells installed by
EPA, plus anomalies in major ion concentrations in water from one of these monitoring wells, provide additional evidence of impact to USDWs and indicate upward solute migration to depths of current groundwater use. Detections of diesel range
organics and other organic compounds in domestic wells < 600 m from unlined
pits used prior to the mid-1990s to dispose diesel-fuel based drilling mud
and production fluids suggest impact to domestic wells as a result of legacy
pit disposal practices.
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Lorenzo
Trad climber
Portland Oregon
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That one is easy. Everywhere. Groundwater contamination is extremely rare in modern wells. Groundwater pollution normally takes place in old oil fields that were drilled pre-1960. They didn't even case off the fresh water.
I guess my question was confusing. I means a good outcome for the Aquifer and its historic users, not for the oil and gas industry. I was looking a bit beyond " we hardly kill anybody with the stuff we pump down there". If you could address what you think happened in Dimock, Pennsylvania; Pavillion, Wyoming; and Parker County, Texas, that would clarify that view.
In particular, what answers do you have for the Agricultural and civic water needs in water stressed regions like the Oglala aquifer?
What I presume is an agricultural advocacy group, Ceres.org doesn't think it's such a hot idea for them.
http://www.ceres.org/issues/water/shale-energy/shale-and-water-maps/water-competition
New York State banned Freacking completely. Why is that?
As long as we are at it. I just read a nyt piece that attributes increased seismic activity in Oklahoma to energy extraction in general. What's the oil industry tech Guy's take on that?
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BASE104
Social climber
An Oil Field
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The Pavillion Field study was later found to be inaccurate.
To boot, the Pavillion Field was just weird. Fresh or crappy fresh water was as deep as a thousand feet. In between the fresh water zones were naturally occurring oil and gas zones. Normally, oil and gas is found thousands of feet beneath fresh water, which tends to be very shallow. I knew someone would pull the Pavillion Field paper out of their ass.
I read the paper. They didn't know how to interpret cement bond logs for one thing. It is what happens when a bunch of groundwater hydrologists who don't know how oil and gas trap write a paper. I'm a geologist, but I don' work hydrology. So I don't publish or work with fresh water. In the areas I work, like most areas, the groundwater is in the top 200 feet. The well itself is usually no shallower than 3000 feet.
Not all geologists are equal. The authors of that paper didn't have a clue. Like I have said, you gotta know how oil and gas trap.
99.99% of the time, your oil or gas target is super deep compared to the base fresh water.
In Oklahoma, the base fresh water has been mapped (using logs from oil and gas wells). You have to case and cement off the fresh water.
Rarely there will be a leaky cement job, but you know it and can either fix it or you will have to plug the well.
The U.S. has had millions of wells drilled since Drake's well. The technology is highly advanced. Casing off and protecting fresh water is tightly regulated. Groundwater protection is THE most important thing for regulators.
Oil companies don't want to be burdened by the Clean Water Act. It would slow drilling permits down to a crawl. I've had to jump through the hoops of drilling on federal land, and it is just a bunch of paper work. As I said, oil and gas are almost always found far deeper than fresh water (The Pavillion Field was an exception to this rule.
The respective states regulate fresh water protection, and do a good job of it. Like I have said, protecting fresh water isn't expensive. It is just an expense, like drilling cost. Protecting the shallow aquifers is easy and only a fraction of the total well cost. You don't dare not follow state requirements on your drilling permit. You can see the surface casing on the logs. Like I've said, casing it off and protecting it is a small fraction of the total well cost, and I've never seen anyone try to get around it. It is literally no big deal.
Around here, we have polluted ground water. Farmers have been fertilizing with nitrate fertilizers for decades and the nitrates have polluted the fresh water. Pregnant women can't drink that stuff without risking blue baby syndrome. Farmers are the ones who trash the aquifer, or shallow ones, anyway. They spray chemicals all over the land and it percolates into the water table.
In the same area are several hundred oil wells. Not one pollution case.
Like I said, it is easy to protect fresh water. Most oil and gas pollution cases are historic, and happened over 50 years ago. There are thousands of little 2 bopd wells that are operated by mom and pop businesses. Some of them are dishonest and dirty. The big companies spend the money to do things right.
So, if fracking trashes fresh water, why do companies routinely sample all surrounding water wells and drill monitoring wells prior to drilling?
So they can show that if the water is full of methane or other chemicals, it didn't come from them. This is now routine. As I said, you can blanket an area with pre-drilling monitoring wells for a pittance.
They do it to show that any methane in the groundwater is either natural or existed before they drilled. The Appalachian Basin is covered with little shallow gas wells drilled by mom and pop shops. Even with their lack of technology, methane in groundwater is natural in virtually every case.
In the NE U.S., over the Marcellus shale gas play, methane is commonly found in the groundwater. If you have ever seen Gasland, the guy who lit his faucet had naturally occurring methane. Even the director of the film was forced to admit it. He was unapologetic. In the real world, you deal with facts. That film was bogus. Only one pollution case was real, and that was from a surface spill. Gas doesn't come bubbling to the surface near fracked wells. You should be able to see that from the log I posted.
I can post a deep Woodford well, but they are super long and wouldn't fit.
Another thing. I'm a straight shooter. I don't bend the truth for anyone. I tell the truth, and I've been doing this for 30 years.
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BASE104
Social climber
An Oil Field
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In particular, what answers do you have for the Agricultural and civic water needs in water stressed regions like the Oglala aquifer?
It is easy to address these things separately.
I've drilled tons of wells through the Ogallala. It is a fantastic aquifer, thick, porous, and icy clean water. I used to go jump into the tailwater pits during the summer to cool off. It is perfect water. Show me a case where the Ogallala was polluted by oil and gas drilling. You might find a couple, out of thousands of wells. Just because somebody is fracking on your farm doesn't mean that your groundwater is at risk. On the contrary. It is easy to protect.
The Ogallala recharges very slowly, and farmers have been depleting it for ages. Where you originally found the water table at 50 feet, it is now often found at 250 feet. Why? So they can grow corn in an arid area. At the same time we pay eastern farmers NOT to grow corn. Hell, a lot of the Kansas and Nebraska corn isn't even for food. It is for ethanol, a process that spews CO2. Oil companies are now hooking up to ethanol plants so that they can use the CO2 for tertiary recovery. A typical well drains only 10% or the oil in place. If you waterflood it you can double that. CO2 floods are fantastic, you can recover up to 80% of the oil in place.
Farmers are the ones who are chewing through the Ogallala. I'm not aware of any major fracking play even beneath the aquifer other than the Niobrara play. Everyone thought that the Niobrara would be a big play, but it turned out that the economic areas were pretty small. Around the Wattenburg Field and a patch in the Powder River basin.
The Wattenburg Field. That field is just NE of Denver and east of Boulder. That field was heated by the Colorado mineral belt, and is pretty isolated. It is also where the guy lit his faucet in Gasland. It is basically a big old gas field, although the Niobrara Chalk is more of an oil play. There is also a small part of the Powder River Basin where the Niobrara is economic.
Do some digging. There was one case where a jury found that an old gas well had polluted the water table. These things can happen, but are rare. Using isotopic analysis, other wells in the area which produced methane were from the water wells themselves. Not from the much deeper gas zones. It was biogenic gas, formed from microbes in the wells themselves.
If you gave a damn about the Ogallala, you would be upset at how fast that thing is being depleted. I drilled five wells a couple of years ago in SW Kansas. As far as the eye could see it was nothing but center pivot irrigation. Crops don't grow that far west other than wheat, which is a dryland crop. All of the corn being grown on top of the Ogallala is depleting it, and as I said, the recharge rate is incredibly slow. It is a non-renewable resource, and the farmers are using it up. Quickly in some areas. The farmers have been using it up far faster than it could recharge.
I've read articles about the deeper Dakota Sandstone aquifer. It isn't as clean, but might be suitable for irrigation. The problem is that the lower the water table gets, the more money farmers have to spend to pump it to the surface. The utility costs of many of those outfits is huge...yet corn grows just fine to the east where there is more rainfall. You can try to dryland farm corn in western Kansas and Nebraska, but you are at the mercy of the rains. Corn is very valuable compared to wheat, so they prefer to grow corn.
I remember looking out at all of that irrigation and not seeing a single weed. An utterly artificial landscape. Every inch of the area I was working was under center pivot irrigation. Every INCH. There wasn't habitat for a sparrow.
So if you want to go off on the Ogallala, you might consider who the culprits are: the farmers. The frack plays on it are small and isolated, and drilling has all but stopped.
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tuolumne_tradster
Trad climber
Leading Edge of North American Plate
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The Pavillion Field study was later found to be inaccurate.
The 2011 DRAFT EPA Pavillion Field study was found to be flawed and EPA abandoned it before it was finalized. Dominic DiGulio, formerly with EPA, resigned from EPA and went to Stanford Univ. There he conducted a comprehensive study with Robert Jackson based on considerable data collected after 2011 and just published their study in the paper I posted ^^^ Additionally they were able to access EPA data via Freedom of Information Act (FOIA) that was included in their study.
To boot, the Pavillion Field was just weird. Fresh or crappy fresh water was as deep as a thousand feet. In between the fresh water zones were naturally occurring oil and gas zones. This statement is accurate.
I knew someone would pull the Pavillion Field paper out of their ass. Not sure whose ass you're referring to here. I posted a paper that was published in the Mar 2016 Environmental Science and Technology. Did you read this paper?
I read the paper. They didn't know how to interpret cement bond logs for one thing. Not sure what paper you are referring to. Cement bond logs are not reliable indicators of well integrity, especially legacy well integrity. Only casing pressure testing can verify well annular seals, especially in legacy wells that can act as vertical conduits for frack fluids injected in a nearby frack well.
"Cement Evaluation Methods to Prove Isolation of Barriers in Oil and Gas Wells:
Should a Cement Bond Log (CBL) Be Run or Required in Every Well?
12 July 2012 George E. King, Apache Corporation
The purpose of this work is to establish whether a specific method or tool is effective in proving cement isolation of a zone, and if the method or tool should be required on the surface casing cement or other cement strings as a part of initial well construction (or, if not required, when it may provide useful information).
**Conclusion # 1. The only cement test method that can confirm zone-to-zone isolation is a pressure test.
The best way to ensure well integrity of the stimulated well is to conduct realtime pressure and flow monitoring during the stimulation. The best way to ensure the integrity of a nearby legacy well is to pressure test the casing.
In the areas I work, like most areas, the groundwater is in the top 200 feet. The well itself is usually no shallower than 3,000 feet. Neither of these statements holds for California, where wells < 1,000 ft deep are fracked and protected groundwater can be 2 to 3,000 ft deep.
The respective states regulate fresh water protection, and do a good job of it. Federal regulations protect groundwater < 10,000 ppm TDS. Unfortunately most states have not adequately characterized the extent of groundwater resources <10,000 ppm TDS. It is very difficult to protect a resource unless you know its extent. Also, it is difficult to design a groundwater monitoring network in advance of a well stimulation to protect groundwater. IMO the best way to protect groundwater is to conduct realtime pressure and flow monitoring during the well stimulation to ensure that the injected fluids and proppant went into the target zone. Some operators are adding short-lived radioactive tracers that can be used to ensure the frack fluids were contained within the reservoir target. If the realtime pressure testing identifies an unintended that might result in frack fluids extending beyond the target zone, then this information can be used to design a groundwater monitoring plan.
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tuolumne_tradster
Trad climber
Leading Edge of North American Plate
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Also, if oil remains below $50/bbl, this is all moot...most frack jobs require >$60/bbl to be economic.
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Lorenzo
Trad climber
Portland Oregon
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To boot, the Pavillion Field was just weird. Fresh or crappy fresh water was as deep as a thousand feet. In between the fresh water zones were naturally occurring oil and gas zones.
I'm sure you see that as an anomaly. It seems to some that disturbing those layers is pure idiocy.
Fresh water at depth is not weird. I paid for a 350 foot well once, and 600 feet in south central PA was pretty common. The ogallala aquifer is measured some places at 500ft.
To boot, those aren't the only issues. I understand North Dakota is still cleaning up a fracking waste spill with the Bakken shale and Missouri River from 2006. Some went directly into the ogallala aquifer.
Some of the stuff they pump in those wells is ( to use a technical term) icky.
Lots of Anes, enes and other gook.
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Dave
Mountain climber
the ANTI-fresno
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"Fresh water at depth is not weird. I paid for a 350 foot well once, and 600 feet in south central PA was pretty common. The ogallala aquifer is measured some places at 500ft."
I paid for a crappy Motorola phone once. And what relevance does that have to a discussion when oil is typically found 1,000's of feet deep?
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Lorenzo
Trad climber
Portland Oregon
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To boot, the Pavillion Field was just weird. Fresh or crappy fresh water was as deep as a thousand feet. In between the fresh water zones were naturally occurring oil and gas zones. Normally, oil and gas is found thousands of feet beneath fresh water, which tends to be very shallow. I knew someone would pull the Pavillion Field paper out of their ass.
Haha. Yeah let's have a discussion without talking about the disasters and what caused them.
We will talk about Pavilion because the industry got caught red handed doing the stuff they say doesn't happen with fracking.
The thing is, Pavillion isn't a one in a million chance you might want to dismiss. It's sloppy control over the hazards you don't want to talk about.
http://insideclimatenews.org/news/29032016/fracking-study-pavillion-wyoming-drinking-water-contamination-epa
The fault wasn't in the weird geology, it's that the oil industry didn't bother to check if it was there or didn't care. Pavilion was fracked because of the appeal of shallow gas. It's cheaper if you don't have to drill so far. oil company's fracked drinking water aquifers knowing they were close.
Published in Environmental Science & Technology, the Stanford study identified chemicals in Pavillion's water related to substances that companies reported using in local fracking operations and acid stimulation, an oil and gas production method. The researchers also found that energy companies frequently fracked at much shallower depths than previously thought, sometimes very close to drinking water wells. In addition, companies fracked into underground sources of drinking water, or USDWs, defined under federal law as aquifers that could supply a public water system. Fracking into USDWs is legal, but the oil and gas industry has long insisted that fracking occurs far deeper than where aquifers are located
Sounds like the company line that "we frack deep and water is shallow" is a myth.
And Pavilion didn't use proper disposal methods for the fracking fluids. Once they were out of the wells.
the other half of the Pavillion story was contamination above ground, from pits used to hold fluids or drilling mud. Prior to the recent fracking revolution, a number of these pits were used without any sort of lining to keep the contents from seeping into the ground. Petroleum-contaminated water from the gas wells went into those pits, as did diesel-fuel-laden drilling mud, so it comes as no surprise that contamination has been found around them. That’s especially true because of the way some of these gas wells were constructed. The researchers again dug through the available well documentation, noting that half of them lacked cement seals around the middle section of well pipe. This “intermediate casing” between the bottom and surface sections is now required in some states, but Wyoming is not one of them. In addition to that missing safeguard, at least a few wells have failed tests for leaks in the well pipe.
Put it all together and the researchers say it’s not hard to imagine that some fracking fluid leaked where it wasn’t supposed to.wqq
The funny part is when a geologist says dealing with the water isn't his job. Really? Why not?
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5under3
Social climber
Ohio
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I once saw a video about a guy named Jed. He was out hunting trying to keep his family fed. In the video he was shootin at some food but he missed and up from the ground came some bubblin crude. Looked like the water was getting pretty contaminated to me!
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