The overwhelming majority of methane found in groundwater samples near natural gas and oil drilling sites in Pennsylvania is naturally occurring, and not related to fracking, according to a new study from Penn State University. The research, which was funded by the National Science Foundation and U.S. Geological Survey, found 99.92 percent of the 20,751 water samples collected near well sites across Pennsylvania showed no signs of methane contamination in groundwater from oil or natural gas wells.
Scale of Research Shows Findings Applicable to Other Shale Plays
The research team, led by hydrogeologist and geochemist Tao Wen, took samples from the southwest, northeast, and northwest regions of the state – areas with extensive drilling history, as well as current oil and natural gas development in the Marcellus and Utica shales. The fact that water samples taken from areas near 12 different drilling sites demonstrated such a rarity of possible human-induced methane migration was unsurprising to the researchers, as Wen notes:
“We expected to see few sites, less than 1%, showing evidence of new (anomalous) methane. We found 17 out of 20,751 samples, or about 0.08 %, that showed possible signs of methane contamination when those samples were collected.” (emphasis added)
The prevalence of hydrocarbons in varying geological formations is what attracts oil and natural gas producers to develop in various plays across the country. As Wen explained, the presence of methane in the groundwater is to be expected in these areas, and not some new phenomenon:
“It’s not uncommon to see methane in groundwater in the Marcellus shale and other shale plays. Also, if methane had been in the groundwater for a long time, bacteria would have reduced the iron and sulfate. The reduced forms would have precipitated as iron sulfide, or pyrite.”
The variance of carbon-bearing geological formations – combined with the variance in the topography of the state – provided the researchers with ample opportunities to collect groundwater samples that would share commonalities with active shale plays across the country. According to the research, “of the 17 samples that came back positive for new methane, 13 came from the northeast. None came from sites within 2,500 feet of known problematic gas wells.”
No samples taken from the southwestern region of the state – one of the most active shale regions in the country – showed any indicators of possible human-induced methane migration.
The researchers defined “problematic gas wells” as those that had received violations from the state’s regulatory agency.
Research Dispels Common Anti-Fracking Activist Talking Point
As Wen’s research (and a number of other studies) shows, naturally occurring methane migration in groundwater wells in shale plays across the country is not a new phenomenon as activists argue. Anecdotes and demonstrations of methane in groundwater wells have been used as one of the most prevalent, deceptive talking points by anti-fossil fuel groups for years.
This deception was most prominently featured in the long-ago debunked film Gasland, in a scene in which a man appears to be setting his water aflame as it pours from his faucet. As research showed, this was possible because the man had his water well set through a well-known carbon-bearing formation, allowing naturally occurring biogenic methane to pass through his water supply.
In the years since Gasland, others have attempted to take advantage of these visually powerful occurrences and scare the public into believing wild claims about the dangers of fracking. Yet once the facts are in – as in the case of a similar incident in Portage County, Oh – the truth lifts the curtain to find naturally occurring methane to be the culprit.
The scale of Penn State’s new study, with more than 20,000 water samples collected across the country’s No. 2 natural gas producer, demonstrates the safety of hydraulic fracturing and other completion techniques used to develop oil and natural gas wells, unconventional or otherwise. Science and sound research yet again disarm activists’ scare tactics, and eliminate common myths and misconceptions used to confuse the public.
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