Fracking- what's your overall assessment?

FarmerDave wrote:
franklin wrote:
Chaz wrote:
Concrete has a half life of about 100 years, so we know the full impact to what's happened in the ground until the concrete starts to deteriorate.
Click to expand...

Where did you get that?
Click to expand...

Yea, that caught my eye too. It seems to me the "half life" depends on the concrete's location and use, and even at half strength, is it not still effective for it's intended use in this case? I'd imagine a Concrete block sitting out in the weather will deteriorate much more quickly than one buried under ground because it doesn't dry out. It's basically a rock when under ground. More durable than some, less durable than others. What is the half life of a rock?

Compare a concrete driveway to the blob at the base of a fence post and see which one deteriorates more quickly. Which one better describes the context we are talking about.

I'm no expert, but...

In this case, the concrete is not used for building a dam or a large building, or even a driveway. It is used to fill the void around the casing, is it not? I'm guessing it's basically used as calking or a sealant to keep gas and fluids from migrating through previously impervious layers of rock that separate the oil and gas from upper layers and not as much structural. It is still held in place by that same impervious rock layer, is it not? It's also under great pressure from all sides. What properties are required for this task and how are they effected over time? Concrete doesn't have much sheer strength, but it does have great compression strength (crush strength). The question is, does it become less effective in keeping the gas and fluids from migrating over time? I tend to doubt to any significance.

What is the average life expectancy of one of these wells? I do know that production tapers off rather quickly on these wells. Huge volumes over the first year or two and then tapering off to something to a small fraction in 10 years. That could be extended with more fracking I suppose, but 100 years is a long time.

When the well is played out, are they not required to plug?

Most of the problems in the past were old wells that were abandoned, allowing the casing to rot out allowing previously separated layers to mingle. It's quite nasty and I'm sure you have seen this, Caz. This is no-longer allowed.

It's one thing to say, we shouldn't do it, but what's the alternative?

Coal?

Solar (apparently you haven't spent much time in NE Ohio). Wind? Those things are fine and dandy, but will never do more than dent our energy needs.

Hydro-electric?

Nuclear?

Drill in someone else's back yard and buy it from them?

I'd be happy as hell of nat gas completely replaced coal use. It also can be used to make liquid fuels including diesel fuel and is way cleaner than using oil.

When something better comes along, then replace nat gas with it.

And of course I am not saying it shouldn't be doe as safely as possible.
Click to expand...

There are steel liners and yes, plugging is done when the well plays out. There isn't significant pressures so no real extreme conditions on the materials.
 
franklin wrote:

There are steel liners and yes, plugging is done when the well plays out. There isn't significant pressures so no real extreme conditions on the materials.
Click to expand...

Yea, I went to far with the "great pressure" thing. I meant significant pressure from the surrounding material that it isn't going anywhere and isn't going to crumble either. The point was, the concrete "half life" is a non-issue.

We are off topic now anyway.
 
Generally good. Though it should be pointed out that "fracking" is not at all what's new here. We were fracking in PA back in the 60's.

What's new with Marcellus is horizontal drilling. Compared to the shallow gas fields that have been drilled for decades, with Marcellus the impact per well is much higher. Vastly higher quantities of fluid and associated disposal issues, higher pressures, a lot more and larger equipment, much larger well pads, longer time periods for each phase of the process, etc.

Half life of the concrete is meaningless. It only really has to hold through the fracking operation itself. During the production phase the pressures are far lower.

Impacts can be split into 2 levels:

Chronic: This is the building of new roads, equipment and traffic on local streets, clearing of forest for well pads, disposal of waste, noise, etc. It's development plain and simple. And in our most rural areas. It's never pretty. And yes, this impact happens, is always going to with any industrial development, and it has been felt.

Screw ups: Whether accidental, or intentional but improper, this is the stuff that's not supposed to happen, but occasionally does. There has been a case or two of failed casings (Dimock), blown pressure caps (Clearfield), a few retaining pond leaks, etc. Not to mention some reports of some dirty operators improperly disposing of cuttings and fluids. These have generally been rare, but when they happen, the impacts can range from severe and largely permanent to minor and temporary.

In the end, my assessment is that it's better than coal. Even modern coal. And since it's displacing coal, I'm for it. That doesn't mean I'm in favor of ignoring the issues.

I'd still prefer nuclear.
 
franklin wrote:
Chaz wrote:
Concrete has a half life of about 100 years, so we know the full impact to what's happened in the ground until the concrete starts to deteriorate.
Click to expand...

Where did you get that?
Click to expand...

A friend who is a chemist, once told me that. If you look around at any concrete that is around about 100 years, it is severely deteriorated. Even stuff from 50 years ago has been replaced with new concrete or resurfaced with some other material. There are wells in ANF that have leakage through and around the casings, most of which are concrete. No one knows what is happening 12,000 feet under the ground, and can't pretend to know.
My biggest concern is the water underground and how it impacts creeks and rivers.
 
No one knows what is happening 12,000 feet under the ground, and can't pretend to know.
My biggest concern is the water underground and how it impacts creeks and rivers.
Click to expand...

There's no concrete deeper than a few hundred feet.
 
Chaz wrote:
franklin wrote:
Chaz wrote:
Concrete has a half life of about 100 years, so we know the full impact to what's happened in the ground until the concrete starts to deteriorate.
Click to expand...

Where did you get that?
Click to expand...

A friend who is a chemist, once told me that. If you look around at any concrete that is around about 100 years, it is severely deteriorated. Even stuff from 50 years ago has been replaced with new concrete or resurfaced with some other material. There are wells in ANF that have leakage through and around the casings, most of which are concrete. No one knows what is happening 12,000 feet under the ground, and can't pretend to know.
My biggest concern is the water underground and how it impacts creeks and rivers.
Click to expand...

Chaz, No offense, but concrete laying around is not the same as concrete used as a sealant a couple hundred feet underground. I do not disagree with you chemist friend, just you.;-)

The likely reason those wells in the ANF are leaking is they were simply abandoned without plugging properly and I'd speculate that many of those are old enough that they likely did not used concrete. Nobody cared back in the day. When they do remediation on those abandoned wells, they don't pull out the old concrete, do they? Think about it.
 
FarmerDave wrote:
franklin wrote:
Chaz wrote:
Concrete has a half life of about 100 years, so we know the full impact to what's happened in the ground until the concrete starts to deteriorate.
Click to expand...

Where did you get that?
Click to expand...

Yea, that caught my eye too. It seems to me the "half life" depends on the concrete's location and use, and even at half strength, is it not still effective for it's intended use in this case? I'd imagine a Concrete block sitting out in the weather will deteriorate much more quickly than one buried under ground because it doesn't dry out. It's basically a rock when under ground. More durable than some, less durable than others. What is the half life of a rock?

Compare a concrete driveway to the blob at the base of a fence post and see which one deteriorates more quickly. Which one better describes the context we are talking about.

I'm no expert, but...

In this case, the concrete is not used for building a dam or a large building, or even a driveway. It is used to fill the void around the casing, is it not? I'm guessing it's basically used as calking or a sealant to keep gas and fluids from migrating through previously impervious layers of rock that separate the oil and gas from upper layers and not as much structural. It is still held in place by that same impervious rock layer, is it not? It's also under great pressure from all sides. What properties are required for this task and how are they effected over time? Concrete doesn't have much sheer strength, but it does have great compression strength (crush strength). The question is, does it become less effective in keeping the gas and fluids from migrating over time? I tend to doubt to any significance.

What is the average life expectancy of one of these wells? I do know that production tapers off rather quickly on these wells. Huge volumes over the first year or two and then tapering off to something to a small fraction in 10 years. That could be extended with more fracking I suppose, but 100 years is a long time.

When the well is played out, are they not required to plug?

Most of the problems in the past were old wells that were abandoned, allowing the casing to rot out allowing previously separated layers to mingle. It's quite nasty and I'm sure you have seen this, Caz. This is no-longer allowed.

It's one thing to say, we shouldn't do it, but what's the alternative?

Coal?

Solar (apparently you haven't spent much time in NE Ohio). Wind? Those things are fine and dandy, but will never do more than dent our energy needs.

Hydro-electric?

Nuclear?

Drill in someone else's back yard and buy it from them?

I'd be happy as hell of nat gas completely replaced coal use. It also can be used to make liquid fuels including diesel fuel and is way cleaner than using oil.

When something better comes along, then replace nat gas with it.

And of course I am not saying it shouldn't be doe as safely as possible.
Click to expand...
I have advocated not getting the gas, I've only said we have to do it with great care, I just question whether concrete to surround the casing is the safest way to protect the water. Let's not forget that there is brine down there, salts if you will, Salts attack concrete. There's also pyritic rock down there and we've seen what happens when water comes into contact with pyritic rock.
 
Chaz wrote:
Concrete has a half life of about 100 years, so we know the full impact to what's happened in the ground until the concrete starts to deteriorate.
Click to expand...

Actually, they use cement in well completions not concrete.
 
franklin wrote:
There are steel liners and yes, plugging is done when the well plays out. There isn't significant pressures so no real extreme conditions on the materials.
Click to expand...

Well, lithostatic pressure is about 1 psi per foot and thermal gradient is around 1.7 F per 100 feet. Maybe not extreme, but it can get uncomfortable.
 
Chaz, I will try to respectfully address your latest.

Chaz wrote:

I have advocated not getting the gas,...
Click to expand...

Viable alternatives please?

I suspect you meant you were not advocating not getting the gas. If that is the case, nevermind. I'd agree with that.

I've only said we have to do it with great care,...
Click to expand...

I 100% agree with that.

I just question whether concrete to surround the casing is the safest way to protect the water.
Click to expand...

Valid alternatives please?

Let's not forget that there is brine down there, salts if you will, Salts attack concrete. There's also pyritic rock down there and we've seen what happens when water comes into contact with pyritic rock.
Click to expand...

Yea, I've seen where water comes in contact with pyritic rock. Aint pretty unless you like orange and lifeless.I haven't forgotten.

But lets look at the brine water and concrete scenerio. Cement actually, which Gone4Day pointed out.

We are talking about drilling more than mile typically. The cement itself is used as a sealant around the casing for a couple hundred feet or so to seal off the hole just punched through impervious rock, thus keeping it impervious cept for the hole in the steel pipe. Usually multiple layers of impervious rock. Below that, it's just more rock around the pipe.

1. So, the question would be, what is the likelyhood that the brine water that may be trying to come up around the pipe, as opposed to through the pipe will come in conctat with said cement.

1.1. If so, what will happen to the concrete.

If you read up on the mechanisms that cause pitting in concrete from salt, you will realize nothing will happen. What causes it on your driveway? I'll tell you. Concrete is fairly porous. A small amount of water soaks into the surface when it gets wet. We can both see this.

Now, when the temperature drops below freezing, what happens? Normally nothing, right? the water is a sold and therefore cannot soak in.

Now add a piece of rock salt, what happens? The snow salt mixture melts into a saline solution (liquid) which can soak into the concrete surface, right?

OK, here is where it gets interesting. Salt is hygroscopic meaning it it draws moisture. It will draw more and more moisture into the concrete surface.

What happens to very cold salt water as the salinity level drops from dilution. It freezes, and in this case a small flake pops out.

It would be a cold day in hell before it gets cold enough to freeze moisture contained in cement, 200 feet under ground.

That is not the entire story, but is what most people refer to as salt "eating" concrete.

Salt solutions tend to be mildly acidic. Don't ask me why. I just read it once. Concrete is on the basic side and as we said, pourous. If you ever made a volcano using vinegar and baking soda, you will know where this is going, but at a snails pace at best. I honestly don't see this as being an issue even after hundreds of years if ever because it is totally surrounded by rock.

As I said in another... This well failures resulting in the orange punch (you referenced ANF) are not a result of concrete failure. They are a result of the casing failure allowing different layers to mix,

.. or a result of the casing being removed believe it or not (shallow well).

Any questions?

Ask you chemist friend if I am right or wrong and if he ways wrong, please be specific. Ask Gulfgreyhound. I think he taught HS chemistry for years. I don't mind learning on occasion.

I don't know the formula for this cement used in well applications, but I'd imagine all this is taken into consideration.

 
Dave you are right I meant I have not advocated not getting the gas, in fact I have gas all the time. They should hook me up once a day and I could supply my vehicle with gas.
Some of the stuff that is in the ground comes up as blow back during the process of fracking. Brine could, but as for brine I'm more curious about what it does to our streams. Whatever it is, it isn't good.
 
Chaz, as long as the well is properly "cemented," I'm not worried about that part.

As far as everything else, I believe we are for the most part on the same page or at least same chapter.

Needs to be done as safe as possible.
 
I have two brothers that have had involvement with the cement used. One helped develop both cements and fracking fluids prior to returning for his graduate work. The other tested cements used as part of his graduate work. Neither has any concerns about the long term reliability of the material if installed properly.

(One of these brothers is well placed in engineering for "big oil". He's completely confident that his company is using very safe practices in their drilling efforts.)
 
Progress of man....

 
As far as I can tell, propane gel fracking is still a viable alternative.
 
barbless wrote:
As far as I can tell, propane gel fracking is still a viable alternative.
Click to expand...

It was mentioned once before here. Was that you?
I've been meaning to look into this. Sounds interesting.
 
Sounds right to me ,Dave. Pipe failure is more likely than concrete, I think.GG
 
Related news.

http://www.pennlive.com/midstate/index.ssf/2015/06/epa_draft_study_shows_no_wides.html#incart_river
 
You must log in or register to reply here.

Latest posts

Montana Angler Fly Fishing
Montana Angler Fly Fishing
Harman's North Fork Cottages


Real Time Data From
the USGS Site

Share this page

Back
Top