Maybe it only seems like forever, but the battle over whether to extract natural gas from shale using hydraulic fracturing (fracking) has polluted the airwaves, cyberspace, and print for a long time now.
The natural gas industry has asserted that fracking is a safe and effective way of tapping new sources of natural gas, the cleanest of the fossil fuels. Others have warned of grave danger from fracking that threatens our drinking water.
Nearly all Republicans have taken up the industry point of view. Nearly all Democrats have taken up the opposition. More than anything else, it’s the political lobbing of slogans and charges that has turned the issue into the pollution of our media. I’ve long wondered, what science is at the basis of the argument.
Guess what? So far, it’s been nothing but computer models. No one has yet done any research.
A new study on fracking
A recent article from the Associated Press, “Can fracking pollute water? Study tries to answer” describes a Department of Energy study now in progress that “may provide some of the first solid answers to a controversial question.” [Link no longer works as of 1/21/2022.]
A company in southwestern Pennsylvania now using the fracking process to extract natural gas has given scientists access to their site. The scientists have performed analyses that allow them to determine a base line. Follow-up testing will enable the scientists to determine which directions the drilling fluids move.
As the diagram shows, fracking involves drilling vertically until it reaches a shale formation. Then the drill turns and continues the borehole horizontally. Drillers pump water, sand, and chemicals into the shale, causing it to fracture and release natural gas, which can then be brought to the surface.
The aquifers that contain drinking water are close to the surface. Pennsylvania’s Marcellus Shale is 8,100 feet deep, separated from soil and groundwater by a thick layer of rock.
But what happens to the water and chemicals that fracture the shale? Which direction do they flow? Can they rise through the rock to the level of the aquifer?
If the fluids cannot penetrate the rock layer, then they can only flow horizontally through the shale. Or, I suppose, down into whatever lies beneath the shale, although the article mentions no such alternative.
If the fluids can penetrate it and rise upward, maybe they will. If they do, it presumably means they will continue to rise until they reach and get into the groundwater.
And if they do, how long will it take? Months? Years? Centuries? By that time, will pollutants still be in the drill water? Or will the water’s journey through more than a mile of rock and soil filter them out?
The DOE’s current study will not answer all of the questions we might have about fracking. No one study can. In fact, no study is real science until enough subsequent studies reach the same conclusions. And then it only validates the answers to the questions that study posed.
Also, if geologic conditions at other drilling sites differ significantly from the one in Pennsylvania, the study will have no bearing on the safety of fracking at these other places.
But it’s a start. Now if we could only get advertisers, talking heads, and political flame throwers to leave issues alone until at least some facts have become established!
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