Natural gas hydraulic fracturing (hydrofracking)

Hydraulic Fracturing & Water Contamination

Hydraulic fracturing or fracking are natural gas extraction employed in deep natural gas well drilling. Once a well is drilled, millions of gallons of water, sand and proprietary chemicals are injected, under high pressure, into a well. The pressure fractures the shale and props open fissures that enable natural gas to flow more freely out of the well.

A loophole in the Safe Drinking Water Act exempts hydraulic fracturing from regulation, despite the threat to drinking water supplies. Unfortunately, Hydraulic fracturing has been linked to contaminated drinking water in communities around the country.

Slick water hydrofracking is different from conventional natural gas drilling in a couple of ways.

First, slick water hydrofracking uses significantly more water than conventional drilling, as well as a “slick water” mixture that is pumped into the shale to fracture the rock and release the gas.

Second, there is an increased potential for toxicity and its long-term impacts.

Finally, there is the environmental impacts of the drilling: surface and subterranean damage including forestland loss, multiple well sites, groundwater and surface water contamination, habitat and species disturbance, and likely an increased number of access roads to the well sites.

What is the problem?

Slick water hydrofracking involves a process that uses 6-8 million gallons of freshwater per fracking  and sand or other lightweight.

Following the injection of both the water and the propane, several chemical-based additives are used to create a more timely, efficient, and overall more economic process.

Some of the chemical additives frequently used include: diesel fuel, biocides, benzene (an additive to gasoline and industrial solvent), and hydrochloric acid.

Companies employing this method of natural gas extraction have resisted efforts to require disclosure of what chemicals and what amounts they use. In that case, only assuring us they use these  chemicals in “small amounts”.

However, “small amount” is generally unspecific, and some of these chemicals (especially benzene) are harmful at any level of exposure, even toxic at an exposure level of only parts per trillion.

Additionally, how companies are containing the slick water post-fracking varies from company to company, sometimes with a great potential for soil and groundwater contamination.

This matters because if any of these chemicals were to mingle with the water table, under which lies the shale with a layer of bedrock in between, it is possible that people’s drinking water could be affected.

However overall, EPA is working with states and other key stakeholders to help ensure that natural gas extraction does not come at the expense of public health and the environment.

                  The Primary concerns include human and environmental exposure to:

*  Radioactivity that is a physical characteristic of Marcellus shale.

*  The hazardous cocktail of hydro-fracking chemicals injected into the ground.

*  Air pollution from diesel engines.

*  Brine that is 5x saltier than seawater that can damage freshwater streams and lakes.

* Hazardous liquid and solid waste that is stored on- site, transported on public roads, and disposed of at municipal landfills.

Works Cited

http://www.peacecouncil.net/NOON/hydrofrac/HdryoFrac2.htm

http://www.citizenscampaign.org/campaigns/hydro-fracking.asp

http://www.epa.gov/hydraulicfracture/