Musings: New Fracking Study Suggests Possible Water Contamination
The investigative reporting website, ProPublica, which often works in conjunction with The New York Times, is reporting on a new study published in Ground Water, the journal of the National Ground Water Association, a non-profit organization of scientists, engineers and businesses involved in ground water. The study was conducted by Dr. Tom Myers, an independent hydrogeologist, and paid for by Catskill Mountainkeeper and the Park Foundation, two upstate New York organizations opposed to natural gas drilling and hydraulic fracturing (fracking) in the Marcellus formation underlying New York, Pennsylvania, West Virginia and eastern Ohio.
Mr. Myers' study was conducted using computer modeling rather than direct observations. It concluded that the natural faults and fractures in the Marcellus formation, exacerbated by the effects of hydraulic fracturing, could allow chemicals to reach surface aquifers in as little as "just a few years." This is in contrast to the existing knowledge that it might take 1,000 years or more for fluids to migrate large distances within these shale reservoirs. The implication is that the Marcellus shale is being pulverized by all the fracturing activity designed to release the trapped natural gas, so that the formation's permeability increases sufficiently to allow contaminated water to migrate thousands of feet upwards to reach the ground water reservoirs that provide the region's drinking water.
According to the description of the study posted on the National Ground Water Association website: "Hydraulic fracturing of deep shale beds to develop natural gas has caused concern regarding the potential for various forms of water pollution. Two potential pathways—advective transport through bulk media and preferential flow through fractures—could allow the transport of contaminants from the fractured shale to aquifers. There is substantial geologic evidence that natural vertical flow drives contaminants, mostly brine, to near the surface from deep evaporite sources. Interpretative modeling shows that advective transport could require up to tens of thousands of years to move contaminants to the surface, but also that fracking the shale could reduce that transport time to tens or hundreds of years. Conductive faults or fracture zones, as found throughout the Marcellus shale region, could reduce the travel time further. Injection of up to 15,000,000 L [liters] of fluid into the shale generates high pressure at the well, which decreases with distance from the well and with time after injection as the fluid advects through the shale. The advection displaces native fluids, mostly brine, and fractures the bulk media widening existing fractures. Simulated pressure returns to pre-injection levels in about 300 days. The overall system requires from 3 to 6 years to reach a new equilibrium reflecting the significant changes caused by fracking the shale, which could allow advective transport to aquifers in less than 10 years. The rapid expansion of hydraulic fracturing requires that monitoring systems be employed to track the movement of contaminants and that gas wells have a reasonable offset from faults."
We are not sure whether this computer modeling of the movement of fluids in the shale formation is correct, but the study will draw interest and support among proponents for blocking the use of hydraulic fracturing of shale formations such as the groups who sponsored the research. One of the leading students of the Marcellus shale and a proponent of using hydraulic fracturing, Dr. Terry Englander, a professor of geology at Penn State University and acknowledged as the "father of the Marcellus shale," questioned the study's results because it goes against everything known about the geological structure and rock mechanics of the formation. But the more interesting point is that Dr. Myers has now reviewed and opined on the Environmental Protection Agency's (EPA) study of possible water contamination in wells in Pavillion, Wyoming due to shale drilling and fracturing. That study's conclusions, which have been questioned due to the sampling techniques of the EPA, have been verified according to Dr. Myers. On the blog for the Center for American Progress Action Fund, a leftist organization opposed to fracking, Dr. Myers was quoted as writing in his review of the test results that "After consideration of the evidence presented in the EPA report and in URS (2009 and 2010), it is clear that 'hydraulic fracturing' (fracking [Kramer 2011]) 'has caused pollution of the Wind River formation and aquifer…' The EPA's conclusion is sound." [Emphasis theirs]
According to the blog, Dr. Myers goes on to detail the geology of the Pavillion area and the waterways in which the polluting chemicals could have migrated into the groundwater. The blog did note that Dr. Myers wrote, "The situation at Pavillion is 'not an analogue' for other gas plays because the geology and regulatory framework may be different." [Emphasis theirs] Opponents of hydraulic fracturing will rally around these two reports because they end the recent string of EPA reversals in its claims about water pollution due to shale-related drilling and fracking.
We initially heard four or five years ago from a geologist friend active in the Marcellus of this theory concerning the migration of fracturing fluids upward via natural faults to possible ground water sources, which is what underlies Dr. Myers analysis. It was suggested by our friend that the likelihood of this transmission happening was minimal, but always a remote possibility. Our friend, who is active in the application of 3-D seismic for developing shale drilling prospects, suggested that the best defense to prevent this scenario from occurring would be for the industry to employ more seismic analysis and especially the use of microseismic for monitoring the hydraulic fracturing of wells. He also thought it would help improve the output from the fracturing operations and possibly reduce the cost of the applications, too. That recommendation is not surprising given our friend's background, but if the industry adopted them, while it would add both cost and time to the development of shale wells, it would certainly provide substantial comfort to citizens, petroleum companies and regulators that the possibility of new well development activity polluting drinking water would be kept to an absolute minimum.
Will the petroleum industry adopt such a strategy? In an era of extremely low natural gas prices, and possibly significantly uneconomic drilling efforts, we are not sure producers will voluntarily adopt such a program. On the other hand, adopting it could sharply reduce the power of the anti-fracturing movement's arguments against the technology, although it would be naive to expect them to end their criticisms entirely. At the end of the day, however, we believe the petroleum industry, and much of the American population, understands that the attacks on horizontal drilling and hydraulic fracturing of shale formations are more about an attack on fossil fuels and not about the technology. Their focus on the technology is due to its success in helping the industry tap unconventional oil and gas resources, which has contributed to the glut of natural gas and its low price that has undercut the economics of clean alternative fuel sources. In the case of natural gas, one needs to remember that at one time this fuel was embraced by clean energy proponents because it represented the cleanest of the fossil fuels, but importantly it was selling at double-digit prices that provided a cost umbrella for expensive wind and solar power. This battle between cheaper, cleaner fossil fuels and more expensive clean energy alternatives will continue to be waged. The petroleum industry needs to seize the initiative for providing greater assurances to the American public that its technology is safe and that its use will benefit society through cleaner energy and positive economic contributions.
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