ProPublica has been at the forefront of examining the possible negative impacts of fracking. Yesterday, they posted a story titled, “New Study: Fluids From Marcellus Shale Likely Seeping Into PA Drinking Water.” Here’s how it starts:

New research has concluded that salty, mineral-rich fluids deep beneath Pennsylvania’s natural gas fields are likely seeping upward thousands of feet into drinking water supplies.

Though the fluids were natural and not the byproduct of drilling or hydraulic fracturing, the finding further stokes the red-hot controversy over fracking in the Marcellus Shale, suggesting that drilling waste and chemicals could migrate in ways previously thought to be impossible.

The study, conducted by scientists at Duke University and California State Polytechnic University at Pomona and released today in the Proceedings of the National Academy of Sciences, tested drinking water wells and aquifers across Northeastern Pennsylvania. Researchers found that, in some cases, the water had mixed with brine that closely matched brine thought to be from the Marcellus Shale or areas close to it.

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At FuelFix, an energy news site associated with the Houston Chronicle, a story from the Associated Press is titled, “New research shows no Marcellus Shale pollution.”

New research on Marcellus Shale gas drilling in Pennsylvania may only add fuel to the debate over whether the industry poses long-term threats to drinking water.

A paper published on Monday by Duke University researchers found that gas drilling in northeastern Pennsylvania did not contaminate nearby drinking water wells with salty water, which is a byproduct of the drilling.

“These results reinforce our earlier work showing no evidence of brine contamination from shale gas exploration,” said Robert Jackson, director of Duke’s Center on Global Change and a co-author of the paper, which appeared online in the Proceedings of the National Academy of Sciences.

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So which is it? Is fracking polluting groundwater or not?

The answer, as always: depends on how you want to frame it.

In short, the study suggests that some areas in which fracking takes place may be more susceptible to pollution from deeper pockets of saltwater. ProPublica cites the study directly:

“The coincidence of elevated salinity in shallow groundwater… suggests that these areas could be at greater risk of contamination from shale gas development because of a preexisting network of cross-formational pathways that has enhanced hydraulic connectivity to deeper geological formations.”

And FuelFix quotes a researcher:

But Vengosh said the research found that naturally-occurring pathways can bring the brine up into shallow aquifers, especially at the bottom of valleys. That could mean some areas are naturally more at risk of groundwater contamination from drilling, he said.

That’s the news. ProPublica draws the distinction very subtly in the second paragraph at top, noting that there is no detected pollution of groundwater with fracking chemicals/solutions. Their summary is slightly misleading; “fluids from Marcellus Shale” requires some additional parsing. The thrust of their argument happens later on:

The study is the second in recent months to find that the geology surrounding the Marcellus Shale could allow contaminants to move more freely than expected. A paper published by the journal Ground Water in April used modeling to predict that contaminants could reach the surface within 100 years – or fewer if the ground is fracked.

Last year, some of the same Duke researchers found that methane gas was far more likely to leak into water supplies in places adjacent to drilling.

Today’s research swiftly drew criticism from both the oil and gas industry and a scientist on the National Academy of Science’s peer review panel. They called the science flawed, in part because the researchers do not know how long it may have taken for the brine to leak. The National Academy of Sciences should not have published the article without an accompanying rebuttal, they said.

FuelFix provides the industry’s response:

“This research demonstrates that freshwater aquifers in northeastern Pennsylvania have not been impacted by natural gas development activities,” said Kathryn Klaber, president of the Marcellus Shale Coalition.

Sometimes with news like this, it’s worth drilling down a little deeper. Pun, sadly, intended.