The fracturing tecnique used in the horizontal well development , needs a lot of wather and there is som fear about pollution of the ground wather.

Do anyone know anything about the timing for restart of the driling activity in the Marcellus shale?

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On the water issue.

When water withdraws are talked about generally, the millions of gallons it takes to frac multi-stage horizontal wells seems like a great deal. Yet put in perspective of other water usage, it can seem like less. For instance, the amount of water used in a frac job is only a fraction of the amount used by golf courses to water greens. The power generation industry uses more water daily than even that. Also, its important to understand that when water is withdrawn from a waterway for drilling and fracing, it should not be taken all at once -- thats what the on site tanks are for -- to hold water that will be needed during the process.

The threat of groundwater pollution by fracturing chemicals is somewhat exaggerated -- Marcellus wells are located about 4,000 to 8,000 feet below the surface. That can be deeper than the Grand Canyon at the south rim, which is about 5,000 ft deep. The Marcellus Shale formation is tightly bound rock -- thats why it needs to be fractured in the first place. Water can collect in those fractures (in some gases even blocking companies from recovering some gas) -- but its nearly impossible for it to migrate up 8,000 ft to ground water, which is relatively near to the surface. Fracing chemicals are not added at the concentrations discussed on MSDS sheets, and usually make up about 0.5 percent of the entire "frac water" mix. The overwhelming majority of it is water, the rest is sand or a similar proppant used to hold the fractures open while gas is extracted.

Rarely, natural gas from another layer/formation can escape from the ground -- that gas will find whatever avenue it can to the surface -- potentially even someone's water well (as in the Dimock case). When that does happen, it can be caused by bad casing/cement jobs; or other unanticipated equipment or procedural problems. Marcellus wells are typically cemented down to where the turn in the horizontal pipe begins to form -- about 500 ft above the target.
Thanks! Always glad to help out.
An environmental lawyer told me that the water use is 2 - 3 million gallons per day. I thought that 2 - 3 million gallons was a total amount, but I did not have a source to cite. What is the approximate amount of water used per well and does it vary depending upon the number of fracs? As a matter of fact, can multiple fracs be done in one well if the Marcellus is thick enough or if done in different directions?
Fracing on vertical wells is done in stages, in order to isolate parts of the well bore to keep pressure where it needs to be for the operation to be successful. It also allows the driller to learn about how the rock reacts to fracing as it goes along -- so operations can be modified for greater production. Each stage can take approximately 500,000 gallons of water -- so in the case your lawyer is addressing, that would be a four or six stage frac (not really2-3 million gallons per day -- more like per site with that number of stages). Thats fairly normal. But lateral lengths of wells have been growing, so 8+ stage fracs are not out of the question.

One of the benefits of horizontal drilling is the ability for drillers to place multiple wells on one drilling pad. In fact, specific purpose drills, designed for the conditions of the Marcellus and northern topography, are coming into the state (see Chief's recent announcement). These rigs can be equipped with "feet" that allow the rig to be walked from one well drilling site on the pad to the next. Drilling multiple wells on a pad disturbs less land, requires fewer access roads, and actualy provides land owners in the well "unit" the opportunity to spread their investment risk over multiple wells, instead of relying on one to come in big.

These multiple wells on one pad, offset directionally as you indicate, can be fraced in the same time frame, which is preferred by drillers, as it would pay only once to mobile equipment, etc. But if necessary, beacuse of weather, or other conditions, they could be fraced at separate times.

I realize 2-3 million gallons sounds like a lot -- keep in mind, that water is not all removed at the withdraw point at the same time and that those sites are approved by proper authoriies (DEP, SRBC, DRBC). Also, its important to remember that many other industries require a great deal more water for activities than fracing. A great example,paricularlyat this time of year, is the golf resort industry. It takes much more water than a few million gallons to keep greens green and ready for visitors. Power plants are one of the biggest users of withdraw water, using millions and millions of gallons on a recurring basis for cooling.
If you want to know the effect of fracking , check out Gas Drilling Dimock Pa. and watch the YouTube of people who have drilling pads on their land. Twenty wells have already been poisoned. To make the argument that " it uses less water than a golf course" is not logical, since golf courses cause terrible pollution due to pesticide use in addition to all the water usage.
Can we just clear this up so people don't think you have anything logical to say about anything..... You say golf courses cause pollution - So then you're opposed to golf courses too? You are such a typical extreme environmentalist with no judgement - just walking around blindly and pointing out things you dont like without coming up with a solution besides "stop that".

Carolyn, take a look at that poll on the front page. I think its pretty telling about how people actually feel about fracking, and what you hear on the news. Almost 90% of people feel fracking is handled correctly now, yet 99% of the news articles you see are saying "people are rising up and finally standing up to oil companies". Well, this recent poll tells a different story. What is happening is that idiots like you who have no clue about the industry, are the only people dumb enough to oppose natural gas drilling, therefore youre the only ones making noise. So, the 10% who think fracking should be altered are making 99% of the noise.

But yeah, you're right, (this is sarcasm coming.....) we should shut down our energy supply, we should import more foreign oil to take its place, we should shut down golf courses because they are bad, anything that uses water, anything that improves our economy, anything that saves us jobs. I seriously hope no sane person actually believes any of the radical garbage you spit out.
Roy,

I've worked in the industry too. Who cares what people feel about how fracking is beibg handled now. The question is how is being handled now and in the future when less well capitalized players and subs get into the field.
Bravo Roy. Poor Carolyn is fairly typical of the NIMBY's (Not In My Back Yard). They really have no rationale for most of the statements they spew out, they just don't want to see anything in their world change. I ran into a similarly minded individual who, after listening to a presentation about how Marcellus wells are drilled and completed stood up and said "I really prefer not to see any type of drilling take place in PA". My response was similar to yours...I said to this gentleman, so then I guess you are OK with sending all your dollars to the middle east for oil imports, increasing the trade imbalances that the U.S. already has, supporting terrorist regimes like Saudi Arabia, killing of U.S. soldiers that we have to periodically send over to the middle east to ensure that we keep the oil supplies stabilized, etc etc etc. Natural gas has the ability to replace at least half of our oil imports. By comparative standards it is much more environmentally friendly and best of all we aren't dependent on anybody like Sheik Abdullah or Hugo Chavez for it. But, god forbid we have gas bubbling up in somebody's water well one out of 10,000 times a well gets drilled. FYI...for the record...methane doesn't "poison" anything. It's not convenient, but it doesn't impart any residual long lasting effects. Once the source of the gas has been identified and resolved you can resume drinking your water. If you doubt the veracity of this, go ask the EPA.
Watch the price of natural gas per 1,000 cubic feet. It's still going on in Lycoming County but only at a few sites currently.
Hi Ralph,

Im confused by both of your comments. And what about Lycoming County?
Exactly what pollution of ground water are you referring to? The ground water is around 600 ft or so, and the drilling is at 8000 ft or so. They set surface casing well below your water table. I am educated in Enviormental Science and all of this pollution and water contamination is all rumour and heresay. This is not the first time these companies have done this. They are very experienced and capable. You telling them about the risks of pollution and water contamination would be like them informing you that there is no "h" in water.

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