Opposing sides continue to spar over study that links oil, gas drilling to groundwater contamination
Source: Greeley Tribune (Colorado), June 5, 2011
Posted on: http://envfpn.advisen.com
Last month, researchers at Duke University unleashed a mini bombshell on the oil and gas industry with a study demonstrating a strong link between oil and gas drilling and groundwater contamination.
But no sooner did their study come out that many refuted its findings, stating researchers’ science was not solid without having baseline readings of existing levels of methane before drilling began.
Duke researcher and professor Robert Jackson, too, states the study hasn’t proven anything, but it suggests drilling on the East Coast has effects on groundwater that should be concerning for the rest of the globe.
“Organizationally, the industry has been unhappy with the methane results, and some environmental groups have been unhappy because we said we didn’t find any evidence of fracking fluids” in the groundwater, Jackson said in a phone interview. “It’s always been a good-news, bad-news story.”
While some industry officials in Colorado continue to evaluate the study’s findings, others believe the state’s regulations on groundwater protection are so strict that it would have to be a concerted effort by the industry to damage groundwater to reach such a level of concern.
“The state of Colorado is very stringent and even getting more so in the testing of wells and monitoring that side of things,” said Ed Holloway, CEO of Synergy Resource, an oil and gas exploration company out of Platteville.
The study comes at an inopportune time for the oil and gas industry, now experiencing another upswing in production, especially in Weld County.
With that comes more criticism, such as the production of “Gasland,” a documentary showing links between drilling and groundwater methane levels across the country. The FRACÂ Act, offered by Colorado Congresswoman Diana DeGette, now awaiting congressional approval, would require the oil and gas industry to reveal chemicals used in hydraulic fracturing beneath the surface.
Though the Duke study title states “fracking” was the likely cause of methane in groundwater, opponents say many simply are confusing terms, making fracking synonymous with drilling.
Fracking occurs thousands of feet below the surface, where chemicals, water and sand are pumped in at high pressures to loosen the tight shale formations to release oil, gas or both. The fluids are pumped back through the steel well bore, encased in cement, to the surface. The cement encasement is provided as a barrier for the groundwater.
Many in the industry do not believe the methane found in groundwater has any origins 7,000 feet below the surface.
“I have a friend in Montana and they have no wells around them, and they have methane in their water,” Holloway said. “With as many wells drilled as we have in Weld County, and maybe one or two incidents where there’s methane in the water, that’s pretty amazing by itself.”
Holloway said groundwater is sacred, even to those in the industry.
“If water contamination from fracking was created by chemicals from fracking, those chemicals would show up in the water system, and it would be very evident,” Holloway said.
Naturally occurring methane is called biogenic, and often found in small concentrations in groundwater. But there are other concentrations that show a definite manmade or deeper influence, called thermogenic methane.
The Duke study found that 60 of 68 wells studied showed elevated levels of methane, and that average concentrations of methane were 17 times higher in water wells within a kilometer of active drilling sites. But opponents say a study of 68 wells in an area that has well over 20,000 is not a good sample, especially when there was no monitoring of methane levels prior to drilling, where methane is known to be prevalent.
“If you’re going to study in an area where you know there’s already methane in the groundwater that’s not a good way to draw conclusions about groundwater,” said Tisha Schuller, president and CEO of the Colorado Oil and Gas Association.
Jackson, one of four authors of the Duke study, which monitored the existence of methane in 68 water wells in Pennsylvania and New York, said the criticism is valid. He said the study marks a good jumping off point for continued looks into groundwater.
Jackson said though the study could use more work, he likens the results to those of smoking.
“It’s a bit like the link between smoking and lung cancer,” Jackson said in the phone interview. “For the initial studies, they didn’t follow individuals through their lives, they didn’t study their health before, and look at the changes in people’s lungs through time. It doesn’t prove smoking causes lung cancer, but it’s a good first step to doing so, and it suggest that that’s a possibility.
“My answer is that what we’ve done doesn’t prove natural gas extraction is causing this,” Jackson said. “It looks at how near you are to a gas well and the quality of your water. The answer was that you were more likely to have problems, but it doesn’t prove a gas well is to blame. But it’s a good first step.”
In Colorado, the laws governing the well bores and casings are tight, Holloway said.
“Not only does your company have to provide it, your vendors all have to verify that they put in that much cement, and all those things,” Holloway said. “You have a double, triple check on verification across the board.”
Jackson said the contamination in groundwater in the Duke study seemed to suggest a deeper level of thermogenic methane.
“When your methane concentrations are high, the methane looks more like deep thermogenic methane when the gas concentrations are low,” Jackson said. “The isotopic data suggests the gas is coming from deep underground.”
In a 10-year study of groundwater contamination of more than 300 water wells in the San Juan Basin in southern Colorado, researchers found little to be concerned with, Schuller said.
“In 10 years, Colorado has been able to definitively prove oil and gas operations do not by their nature affect groundwater,” Schuller said, noting the study has been forwarded to the U.S. Environmental Protection Agency. “It’s a good, solid study that shows if you’re doing drilling and monitoring groundwater, that drilling” isn’t causing problems.
She said the Duke study “does not inform our understanding of groundwater.”