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How Fracking (hydraulic fracturing) Works -or- how to make water that lights on fire

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If you look around on YouTube, it is fairly easy to find videos showing people who have flammable tap water. The water coming out of the faucet will light on fire and burn with an open flame. Here are several examples:

What is happening here? Natural gas (mostly methane) is getting into the aquifer. When the water is brought up out of the water well into the tap, the methane comes with it. The methane bubbles out of the water and can burn in the air.

Generally speaking, natural gas does not get into aquifers, so what is causing it to happen in these videos? According to the following article, in many different parts of the United States, a new natural gas drilling technique called fracking (aka hydraulic fracturing) is causing this problem and many other contamination problems:

A Colossal Fracking Mess

The Delaware is now the most endangered river in the country, according to the conservation group American Rivers.

That’s because large swaths of land—private and public—in the watershed have been leased to energy companies eager to drill for natural gas here using a controversial, poorly understood technique called hydraulic fracturing. “Fracking,” as it’s colloquially known, involves injecting millions of gallons of water, sand, and chemicals, many of them toxic, into the earth at high pressures to break up rock formations and release natural gas trapped inside. Sixty miles west of Damascus, the town of Dimock, population 1,400, makes all too clear the dangers posed by hydraulic fracturing. You don’t need to drive around Dimock long to notice how the rolling hills and farmland of this Appalachian town are scarred by barren, square-shaped clearings, jagged, newly constructed roads with 18-wheelers driving up and down them, and colorful freight containers labeled “residual waste.” Although there is a moratorium on drilling new wells for the time being, you can still see the occasional active drill site, manned by figures in hazmat suits and surrounded by klieg lights, trailers, and pits of toxic wastewater, the derricks towering over barns, horses, and cows in their shadows.

The real shock that Dimock has undergone, however, is in the aquifer that residents rely on for their fresh water. Dimock is now known as the place where, over the past two years, people’s water started turning brown and making them sick, one woman’s water well spontaneously combusted, and horses and pets mysteriously began to lose their hair.

In the following video, a woman in New York talks about the contamination of her drinking water from fracking chemicals:

Toxic chemical contamination in Pennsylvania:

This brings up the obvious question: What is Fracking? The following video provides an excellent explanation of the process:

As described in the video, a natural gas well is drilled like any other well (a process we now know much more about thanks to the BP oil spill in the Gulf of Mexico). A drill string drills a hole deep into the earth (see How Oil Drilling Works for details). Then, as seen in the previous video, horizontal drilling techniques can be used to drill horizontally as well.

Once drilling is complete, the drill string is extracted and the well bore is lined with steel pipe. Cement is pumped around the outside of the pipe to lock it in place. Once the cement hardens, shaped charges are pushed down the pipe to perforate it and start fracturing the rock around the steel pipe. Then gallons of “fracturing fluid” at high pressure are pumped in. This is where the name “hydraulic fracturing” comes from – water is one of the fluids commonly used. In the best case the water is mixed with sand, and the grains of sand act as a “proppant”. The grains of sand get into the fractures and will hold them open once the water pressure is released.

A sand/water mix is the best case. Apparently there are many toxic chemicals used in some fracturing fluids. So if the fractures stretch into the aquifer (as apparently they often do), those chemicals plus oily residue and chemicals from the shale formation get into the drinking water.

The following video, from the industry, explains how hydraulic fracturing is harmless to communities and to the environment:

A quote from the previous video:

There are numerous precautions that are used in fracture stimulation, where this process does not in any way harm the environment around these wells. There are multiple layers of protection that are in place, from steel casing to cement around the casing that maintains that fracture stimulation just within the formation. We have techniques and technologies that allow us listen and hear where the rock is cracking, so we know that the fracture stimulation stays within the Barnett. So fracture stimulation is absolute very environmentally friendly technique for producing natural gas.

It would seem, based on the evidence shown above, that this statement is untrue. The following video tells the other side of the story and discusses the exemptions from environmental laws that the natural gas industry enjoys:

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