State of the Planet

News from the Columbia Climate School

Hydraulic Fracturing – Potential for Contamination of Drinking Water Sources

hydraulic-fracturingHydraulic fracturing is a technique used by the oil and gas industry to facilitate natural gas recovery in underground low permeability coalbed methane wells. This operation improves the extraction efficiency of methane by creating fissions or fractures in underground rock formations, generally 5,000 – 20,000 feet below the ground surface. Highly pressurized hydraulic fracturing fluids, up to 15,000 PSI, are injected into the reservoir to force open the tiny cracks in the rock to allow for the resource to flow more readily. The hydraulic fracturing fluid used is comprised of 99.5% water and proppant material, typically sand, used to keep the fissures open. Anywhere from 50,000 – 350,000 gallons of fracturing fluids and 75,000 to 320,000 pounds of proppant material is used in a single drilling. The cause for concern, however, is the 0.5% of special purpose additives used to enhance the effectiveness of the fracturing fluid. These chemicals include potentially toxic substances such as benzene, formaldehyde, ethylene glycol, glycol ethers, hydrochloric acid, and sodium hydroxide. The danger lies in the potential for contamination of underground sources of drinking water from the 20 – 40% of the fluid that will remain underground. This is a significantly large amount given the initial amounts of fluids being injected into the ground.

In 2004, the US EPA conducted a study assessing the potential for contamination of Underground Sources of Drinking Water (USDW) due to the injection of hydraulic fracturing fluids into coalbed methane reserves. The study concluded that hydraulic fracturing posed little or no threat to drinking water so long as diesel fuel, which contains carcinogenic compounds benzene, ethylbenzene, toluene, xylene, and naphthalene was not injected into the wells. And upon the release of this study, an agreement with the service companies was reached to stop using diesel fuel as a component of fracturing fluid. Furthermore, the EPA found no confirmed cases or evidence of contaminated drinking water linked to fracturing fluids injected into underground coalbed wells.

ProPublica, an independent, non-profit newsroom that produces investigative journalism in the public interest has found many gaps in the EPA conclusion that hydraulic fracturing poses no risk to drinking water. In addition, many of the regulations are loosely enforced, especially in regards to using diesel fuel as an additive. More than 1,000 cases of water contamination across seven states have been found to have originated from a fracturing process. A recent New York Times article also documents the failure of an oilfield company failing to report fracturing violations to the EPA.

The Marcellus Shale, an underground rock formation that runs from northern Kentucky and eastern Ohio through upstate New York, is one example where hydraulic fracturing is used for gas extraction. An enormous amount of 50 trillion cubic feet of available natural gas is estimated to reside in the Marcellus Shale. This is approximately a two-year supply for the US, amounting to a value of around $1 trillion. However, much of the natural gas lies within New York City’s upstate 1,900 square mile watershed. Measures have been taken by New York State environment officials that will not allow natural gas drilling inside the watershed and within a buffer of the borderline, although, concerns still lie in the transport of contaminated groundwater. What is significant is that the state government is starting the recognize the potentially damaging effects of natural gas drilling on drinking water supplies. After several accounts of water contamination due to hydraulic fracturing, the EPA has decided to further its study in assessing the extent of damage natural gas drilling has on the environment and drinking water sources. The EPA has said that it will spend nearly $2 million on the research this year, and hopefully, this will push the progress of the FRAC Act, a House bill that would establish federal environmental controls over the process of hydraulic fracturing.

Banner featuring a collage of extreme heat images.

Recent record-breaking heat waves have affected communities across the world. The Extreme Heat Workshop will bring together researchers and practitioners to advance the state of knowledge, identify community needs, and develop a framework for evaluating risks with a focus on climate justice. Register by June 15

Notify of

Inline Feedbacks
View all comments
Johanne Dion
14 years ago

For the past few years, there has been some exploratory drilling by gas companies in the Saint-Lawrence Valley in the Utica shale in Quebec. There is a drilling site near Saint-Edouard: and another is planned in Saint-Marc-sur-Richelieu if the go-ahead is given: . In Saint-Marc, not many people have private wells for their water because the water is not of very good drinking quality, but the fear is that the enormous amount of wastewater produced by hydro-fracturation is going to be just too much for local municipal water treatment plants. Plus, the worry is that these municipal plants are not equipped to deal with what will come out of these drilling installations, and since the “treated” water returns to the Richelieu River, source of drinking water for many towns and villages downriver, that is a concern too. We have heard that fracking wastewater is often too salty, or contaminated with heavy metals, and is often radioactive. Our provincial government assures us that regulatory laws on natural gas exploration and extraction are going to be drawn up soon, but have not been made public yet. We are not even sure if the Ministry of Natural Resources or the Ministry of the Environment will be in charge for overseeing this industry. Local populations are asking for a moratorium until we know more about hydraulic fracturing and the laws are drawn and enforced, but the Minister of Natural Resources seems ready and eager:

Dan Puroclean
14 years ago

Federal environment officials investigating drinking water contamination near the ranching town of Pavillion, Wyo., have found that at least three water wells contain a chemical used in the natural gas drilling process of hydraulic fracturing. Scientists also found traces of other contaminants, including oil, gas or metals, in 11 of 39 wells tested there since March 2009.

RF Filter
13 years ago

Natural gas plays a key role in our nation’s clean energy future and the process known as hydraulic fracturing is one way of accessing that vital resource. HF is used by gas producers to stimulate wells and recover natural gas from sources such as coalbeds and shale gas formations.

Healthy Andy
13 years ago

Any time I read about something like this, I get nervous. I get it that we need alternative energy sources, but our water supply is already so ridiculously contaminated that I can’t reconcile the cost. There was a recent study showing that the majority of city water supplies tested had significant levels of chromium-6, a potent carcinogen (that’s the chemical made famous by Erin Brovovich). Better to tread safely than pollute our water supply more.

Katrina Oakley
13 years ago

I think there needs to be a lot more research on the fracking process and the chemicals used. as stated by Healthy Andy, our safe drinking water is very scarce. If we keep putting up with the unknown, we will all have to filter our home tap water. This fracking is putting too many unknown contaminants in our water supply. Water filter companies, like Multi-Pure, are scrambling to find out what is going into the water, so they can develop a filter to take it out.

As our safe water diminishes, water filters will be a required appliance as important as indoor plumbing.

Water Jane
11 years ago

I think there has been plenty of research. It took me five minutes to find and watch a video on how the drinking water is protected. They use dual layers of cement around the pipe and a metal pipe in between.