Well water contamination study inconclusiveAugust 9, 2013
A. Lee Graham
The results are in, and they prove nothing.
New findings of a University of Texas at Arlington study of well water contaminants near natural gas drilling sites offer insights but no conclusions.
That’s probably no surprise to those on both sides of the hotly debated issue. They’ve spoken for and against natural gas drilling and-or potential water contamination for years. Still, some results surprised even the researchers behind the first-of-its-kind analysis.
“The most surprising thing was methanol and ethanol in wells,” said Brian Fontenot, a UT-Arlington graduate and lead author on the study, which was published online by the journal Environmental Science and Technology.
Traces of methanol and ethanol – and metals such as arsenic, barium and selenium – can occur naturally in groundwater, but samples from some of the 100 private water wells reviewed in the study exceeded 10 micrograms per liter, exceeding the Environmental Protection Agency’s standards for safe drinking water.
Methanol and ethanol usually break down rapidly and are short-lived in the environment, which has researchers scratching their heads at how samples were found during research.
“They’d be really fleeting and break down rapidly, so for us to find it in these samples we were doing, that’s a surprise,” Fontenot said. “We’re not sure what to think about that just yet.”
That’s why the study is the first of a planned series intended to probe specific causes of elevated contaminant levels in areas near natural gas drilling activity. The initial study focused on the presence of metals such as arsenic, barium, selenium and strontium in water samples.
Samples were taken from private water wells in and near the Barnett Shale in summer and fall 2011. Persuading landowners to have their wells evaluated was sometimes challenging.
“We can’t just go where we want because they are private owners’ wells,” Fontenot said. “So we had UT-Arlington issue a release that we were working on a study.”
Offering free water-quality testing often persuaded landowners to participate.
Joining Fontenot in conducting the study was Kevin Schug, a UT-Arlington associate professor of chemistry and biochemistry; Zacariah Hildenbrand, a longtime researcher and founder of Inform Environmental LLC; and several other researchers.
The team accepted no outside funding to ensure objectivity and lessen any potential perception of favoring certain interests. Instead, they dug into their own pocketbooks to fuel many trips to and from well sites. They also accepted donated lab equipment to test samples they collected.
“We don’t have a dog in the fight here; we just wanted the water to speak for itself,” Hildenbrand said.
But at least one energy pundit dismisses the study as speculation.
“It’s definitely inconclusive,” said Ed Ireland, executive director of the Barnett Shale Energy Education Council of Fort Worth.
Asked to comment on the study, Ireland emphasized its lack of conclusive findings, even calling it speculative in some parts. Portions of the study echo that perspective.
“To draw definite conclusions about the origin of elevated constituent levels in these water wells would require a focused study of groundwater before, during and after natural gas extraction activities,” the study said.
Drawings those conclusions would be “logically impossible,” the study said, because industrial activities have occurred for more than a decade in the area.
“Given this limitation, our discussion of the source of elevated constituents is speculative,” the study said.
Fontenot acknowledged that those on both sides of the issue could use the study’s findings to defend their respective positions.
“We recognize that people will take away from this study whatever view they came in with,” Fontenot said. “With an issue that’s this contentious politically, we definitely were not surprised by this.”
The researchers took 91 samples from areas with one or more gas wells within a 5-kilometer radius. Nine more samples were taken from locations inside the Barnett Shale and more than 14 kilometers from a natural gas drilling site, or from sites outside the Barnett.
Each sample was compared with data previously collected on water wells in the same counties from the Texas Water Development Board groundwater database for 1989-1999, before natural gas drilling gained momentum.
Ethanol and methanol weren’t the only two substances whose concentration raised eyebrows. So did arsenic. While arsenic occurs naturally, its North Texas concentration is usually no higher than 10 micrograms per liter. But some samples in the study found levels comparable to concentrations more commonly found in West Texas due to that area’s more saline groundwater and to pesticides.
“In this region, it’s rare to get arsenic over 10,” Fontenot said.
Hoping to resolve such mysteries, the research team already is conducting a second study in the Permian Basin west of Abilene. Researchers are contacting landowners in the area, particularly in the Cline Shale, to collect water samples.
The study is expected to last up to two years.
More information on the research effort is available at www.uta.edu.