Photo courtesy of Joshua Doubek via Wikipedia Commons.

Here’s How Fracking Works, And Why It Fuels Controversy

Hydraulic fracturing, or fracking, is a controversial method of drilling for gas that involves breaking up deposits by pumping a high-pressure mix of water and chemicals deep underground.

The gas fracking industry says it’s beneficial for the economy and progresses the U.S. towards energy independence. Activists, however, say the process generates toxic waste and pollutes the surrounding groundwater.

Fracking currently makes up about 23% of the nation’s energy production, according to the Department of Energy.

Here’s how fracking works and why it’s so controversial.

The process

Fracking has been made economically viable over the last decade due to technological advances that have allowed horizontal drilling (see the illustration below) to depths of up to a mile underground, according to the University of Duke dukenvironment Magazine.


Illustration courtesy of the U.S. Department of Energy (DoE). Text added by Curiousmatic.

This enables access to shale, the layer of fine-ground sedimentary rock that often contains deposits of oil and natural gas, according to the DoE.

The high-pressure fracking fluid mix cracks open the shale and allows the deposits to flow out.

Often a proprietary mix owned by the energy companies, however, the contents this fluid are often protected as trade secrets (although a few companies have disclosed the contents recently,) according to dukenvironment magazine.

According to a DoE-commissioned report by the non-profit Oklahoma Ground Water Protection Council (OWGWPC), the mix consists of about 98% water and sand (the latter of which helps prop open fissures), with the rest being chemicals.

A report by the industry organization American Petroleum Institute puts the percentage of chemicals at closer to 0.5%.

Although it varies widely, the typical well requires between two and four million gallons of water to be ready for extraction, according to the OGWPC.

The organization lists the following as ingredients that are commonly, but not always used:
(it’s likely that companies use chemicals not listed here as well)




Common application


Dissolves minerals

Swimming pool cleaner

Polyacrylamide & Mineral Oil

Minimizes friction between fluid and pipe

Soil conditioner

Ethylene Glycol

Prevents deposits in pipe

Antifireeze, household cleaners, de-icing

Borate Salts

Maintains fluid viscosity in high temperatures

laundry detergent, hand soap

Sodium/Potassium Carbonate

Maintains effectiveness of other compunds

Washing soda, detergent, glass, ceramics


Eliminates bacteria

Disinfenctant, sterilization of medical gear

Guar gum

Thickens water to suspend sand

Cosmetics, baked goods, ice cream, toothpaste

Citric acid

Prevents the precipitation of metal oxides

Food flavor additive


Increases viscosisty

Glass cleaner, antiperspirant

Silica, quartz sand

Allows fractures to stay open

Drinking water filtration, play sand, concrete, mortar

Why activists are against it

The process wastes millions of gallons of water, contaminates it with chemicals and radioactivity, and leaks chemicals into people’s drinking water, according to Democracy for America.

And indeed, a study by geologists at Duke University showed that there were measurable samples of methane in drinking water collected around the Marcellus Shale region in northern Pennsylvania and New York. Levels were 17 times higher in wells that were a kilometer or less from fracking sites.

Neither did the preliminary conclusion of a study by the Environment Protection Agency, according to the Huffington Post, although that study was later criticized for excluding information about contaminated wells, as reported by the Los Angeles Times.

Perhaps the most dramatic display of contaminants have been the existence of the flammable gas methane in the tap water of areas very close to fracking sites, as shown below. It’s unkown what, if any, harmful effects methane has on people, dukenvironment writes.

Another concern over fracking is the wastewater it produces, which is 10 to 20 times more saline than seawater, is naturally radioactive, and contains levels of metals far above safety standards, according to dukenvironment.

Companies have previously been fined for incorrectly disposing of this water, which poses a threat to drinking water if there is a spill.

What the industry is saying

The American Petroleum Institute, which represents the interests of energy companies, says that fracking is a proven technology that provides clean gas, creates tens of thousand of  jobs and hundreds of millions of state revenue. It also helps the U.S. shed its dependence on energy from foreign sources.

Compared to coal, the natural gas produced by fracking emits almost no no mercury, sulfur dioxide and particulates when burned, dukenvironment writes, and the horizontal wells leave a much smaller footprint on its surroundings.

The API also argues that regulations, such as the Safe Drinking Water Act, are already in place, and the industry is continually developing guidance documents and best practices when it comes to environmental concerns.

But whichever opinion you’re of, fracking is poised to continue – the Department of Energy estimates that shale gas will account for 13.6 trillion cubic feet, or half of the annual U.S. gas production, by 2035.

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Ole Skaar