The U.S. is in the midst of a natural gas boom, and a new investigation into four of the states producing the most natural gas challenges energy industry assurances that the extraction process does not pollute groundwater.
The Associated Press collected data from Pennsylvania, Ohio, West Virginia and Texas, and found hundreds of drilling-related complaints from the past several years, according to a report published online Sunday. Though the states were inconsistent in the information they released, the investigation found that some of these complaints led to confirmed cases of contamination of well water.
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The results of the AP's investigation were as follows:
In West Virginia, officials cited about 122 complaints of well-water contamination over the past four years. Drillers "agreed to take corrective action" in four of those cases.
Pennsylvania's Environmental Department confirmed 106 well-water contamination cases since 2005, and said the state may release more data in the coming months.
Ohio fielded 190 complaints from January 2010 through December 2013. The state confirmed six cases of well-water contamination, but Ohio Department of Natural Resources spokesman Mark Bruce said none of the six cases were related to natural gas extraction.
Texas provided a spreadsheet with more than 2,000 complaints, 62 of which are related to oil and gas extraction. A state official said that Texas has not confirmed a single instance of well-water contamination related to drilling in the past 10 years.
Though proponents of natural gas argue that it burns cleaner than other fossil fuels such as petroleum and coal, environmentalist opponents say the process of removing the gas from deep rock formations endangers local water supplies.
The extraction process, known as hydraulic fracturing or "fracking," involves pumping water, sand and chemicals into the ground at extremely high pressures to puncture the buried rock that harbors the gas. When some of that liquid returns to the surface in the form of waste, it has been found to contain "large quantities" of groundwater, in addition to "salt, drilling chemicals, heavy metals and naturally occurring low-level radiation," according to the AP report.
In addition, the wastewater produced by fracking is sent to sewage treatment plants "that cannot remove some of the contaminants before the water is discharged into rivers and streams that provide drinking water," according to a 2011 New York Times report.
In its description of fracking, energy industry advocacy group Western Energy Alliance states that "fracking has been performed in more than 1.2 million wells since 1949 with an exemplary safety record and no documented cases of contamination of drinking water."
The AP investigation is far from conclusive for a few reasons. First, the complaints cited are related to both fracking and traditional gas drilling, so it's difficult to separate the impact of the two. Plus, fracking in the U.S. is not limited to these four states. An interactive map produced by the environmental law organization Earthjustice suggests as many as 18 states allow fracking.
In fact, the U.S. surpassed Saudi Arabia last year to become the world's largest supplier of oil, largely because of shale oil and natural gas extracted through fracking, according to consulting firm PIRA.
From the information that the four states released to the AP, however, it's not possible to truly determine the effect of the natural gas boom on drinking water. Aside from the possible environmental ramifications, the AP report suggests that "considerable confusion" over the scope of the problem makes it difficult for the public to trust assertions from drilling companies that fracking isn't a threat to water supplies.
"If the industry has nothing to hide, then they should be willing to let the facts speaks for themselves," Scott Anderson, an expert on oil and gas drilling with the non-profit Environmental Defense Fund, told the AP. "The same goes for regulatory agencies."
The U.S. Environmental Protection Agency is in the midst of conducting a major study on fracking's effect on ground water; it expects to release its results sometime this year.
You can find the full report on the AP's investigation into well-water contamination complaints here.
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