Duke University Study Connects Water Contamination to Fracking Natural Gas WellsMay 10th, 2011 | By Mark | Category: Lead Articles, Regulation
Environmental advocates and the people who live and work on the land above the Marcellus Shale Formation in New York and Pennsylvania have long contended that fracking — also known as hydraulic fracturing, a controversial technique in which thousands of gallons of toxic liquids are injected deep into the earth to break up rock formations and free natural gas deposits trapped within — has hopelessly polluted the water there.
The natural gas industry has repeatedly denied that fracking destroys the environment, but a study by researchers at Duke University published today in the Proceedings of the National Academy of Sciences, demonstrates unequivocally that fracking does, in fact, contaminate the water in the area where is used.
The study examined groundwater obtained from 68 wells above the Marcellus and Utica shale formations throughout Pennsylvania and New York. The researchers found that the groundwater in the areas near active fracking wells contained, on average, methane concentrations 17 times higher than wells located where fracking was not taking place. Moreover, some of these wells had methane concentrations well above the “immedate action” hazard level as defined by the U.S. Department of the Interior.
The researchers also specified six recommendations to “improve public confidence in shale-gas extraction.” These recommendations include:
- Initiate a medical review of the health effects of methane.
- Construct a National Database of Methane, Ethane, and Propane Concentrations and other Chemical Attributes in Drinking Water.
- Evaluate the Mechanisms of Methane Contamination in Drinking Water.
- Systematically Sample Drinking Water Wells and Deep Formation Waters.
- Study Disposal of Waste Waters from Hydraulic Fracturing and Shale-Gas Extraction.
- Refine Estimates for Greenhouse‐Gas Emissions of Methane Associated with Shale‐Gas Extraction.
The last point is particularly important, given that methane is a highly destructive greenhouse gas that is 21 times more damaging to the atmosphere than CO2.
From the Duke paper:
Studies have estimated methane losses to the atmosphere from natural‐gas production to
be between 1 and 3% of total gas production per well.37 The majority of these losses are
“fugitive emissions” from the movement and transport of methane, particularly leaks at
compressor stations and in underground pipes. In a summary for the U.S. Environmental
Protection Agency, Kirchgessner and colleagues estimated methane emissions associated
with the U.S. gas industry to be 6.04 ± 2.01 x 1012 g CH4 in 1991, an amount that accounted
for 19‐21% of all U.S. methane emissions attributable to human activities.38 A new analysis
from Cornell University suggests that methane emissions associated with shale‐gas
extraction may be substantially higher. That study estimated that 3.6 to 7.9% of the
methane from shale‐gas production escapes to the atmosphere over the lifetime of a well
through leaks and venting. Regardless of the accuracy of the new estimate, the controversy
it generated highlights weaknesses in the data used for such calculations and demonstrates
that no consensus exists as to the extent of methane losses to the atmosphere from shale-gas
The Duke researchers also made a pair of policy recommendations:
- Consider Regulating Hydraulic Fracturing Under the Safe Drinking Water Act – Fracking is currently unregulated by the EPA. Indeed, fracking fluids were specifically exempted by the federal government from EPA regulation by the Bush administration via the 2005 Energy Policy Act, which states that“the underground injection of fluids or propping agents (other than diesel fuels) pursuant to hydraulic fracturing operations related to oil, gas, or geothermal production activities” from the definition of “underground injection.”
- Fully Disclose Chemicals Used In Hydraulic Fracturing – Natural gas companies are not required by most states or federal law to disclose the toxic brew of chemicals that they routinely inject into the earth during the fracking process, information they claim is a proprietary trade secret. However, the recently re-introduced FRAC Act would require a full disclosure of these chemicals.
Unsurprisingly, the natural gas industry immediately attacked the Duke study. A spokesman for Energy In Depth, a front group for the natural gas drilling industry, lashed out at the Duke researchers in the Christian Science Monitor for what he called a lack of baseline data.
In addition, Aubrey McClendon, the president of Chesapeake Energy, said that Pennsylvania’s water was contaminated with methane long before his company drilled hundreds of fracking wells in the area.
From the San Francisco Chronicle:
“You can go back 100 years and people talk about gas in their water wells,” he said. “It’s not from fracking.”
McClendon said Marcellus drilling may have contributed “inconveniences,” and said “every one of those problems has an engineering solution to it.”
Unfortunately, McClendon’s statements don’t exactly square with the experiences of the folks who live in the watershed areas where fracking is under way — particularly those people who had to be evacuated when one of Chesapeake’s wells exploded a couple of weeks ago, sending thousands of gallons of toxic fracking fluid coursing over Pennsylvania farmland and into a local creek there.
The fact is, McClendon’s statements notwithstanding, fracking has undeniable consequences for our air and water. The Duke study makes that abundantly clear — and the environmental cost of getting that methane out of the ground and into the market are a lot higher than the natural gas industry cares to acknowledge.