By Roberta Attanasio, IEAM Blog Editor
Diagram of a fracking operation, courtesy of , .
Hydraulic fracturing, or fracking – the process of extracting natural gas by injecting wells with mixtures of water, sand, and even toxic chemicals at an extremely high pressure – may contaminate drinking water and affect human health, among other unwanted consequences. By creating fissures in rocks such as shale located thousands of feet underground, fracking releases the contained gases, forcing them into the wells and back up to the surface along with wastewater, which then needs to be disposed of safely. Fracking a single well requires between two and five million gallons of local freshwater and generates enormous amounts of wastewater. Chrisitana Peppard, professor of science, theology and water ethics at Fordham University in New York, : “The standard approaches to deal with the contaminated water are to hold it in lined pools above ground or inject that water deeper into the earth, which could cause earthquakes.”
Concerns related to water do not involve only the use of large amounts of freshwater and the disposal of toxic wastewater, but also the contamination of drinking water with methane – which has been reported in several instances across the country. A showed that drinking water wells became contaminated as a result of faulty fracking-related infrastructure, as well as naturally occurring high methane levels. Thomas Darrah, one of the scientists involved in the study, said in a : “There is no question that in many instances elevated levels of natural gas are naturally occurring, but in a subset of cases, there is also clear evidence that there were human causes for the contamination. Our data suggests that where contamination occurs, it was caused by poor casing and cementing in the wells.” Robert Jackson, another scientist involved in the study added, “In some cases homeowners’ water has been harmed by drilling. In Texas, we even saw two homes go from clean to contaminated after our sampling began.”
Drinking water safety notice, New York City. Courtesy of , .
At this point, it is reasonable to ask: how many residents are directly exposed to the dangers posed by fracking? Russell Gold and Tom McGinty that, as of last year, at least 15.3 million Americans lived within one mile of a fracking well. In other words, fracking wells are becoming an unsightly presence in many U.S. backyards, posing still poorly defined and, in the current conditions, almost unavoidable risks to these households. A well requires “truck-sized containers of water and sand, mixers, stadium lighting, pumps, chemical storage, and injection vans and recreational-vehicle command centers to orchestrate the operation.” Unsurprisingly, fracking is frequently considered a disruptive force by communities around the country. However, a combination of Wall Street financing and rapid technological innovation is leading to more and more fracking despite an absence of appropriate measures to ensure safety; our understanding of the risks associated with fracking remains very limited.
For example, in a , Jackson and other collaborators speculate that the presence of methane in drinking water could represent a precursor to other toxins, including arsenic, radioactive radium and other metals. Although the researchers do not yet know whether or not this is the case, a few recent studies suggest that it is a possibility.
Results from the on the impact of fracking on residents suggest that fracking could be associated with adverse health effects in people living in proximity of the drilling operations and support the need for further research into the impact of fracking-related activities. , Katie Brown, spokesperson for the pro-oil and gas-drilling group Energy in Depth, said the study was “just a poll” that contradicts evidence from direct measurements and that the fracking sites are closely monitored for possible pollutants.
Fracking drill and wastewater pond, courtesy of , .
However, according to from the National Institute for Occupational Safety and Health, workers at fracking sites may be exposed to high levels of benzene, a substance known to cause cancer and acute toxicity to the nervous system, liver, and kidneys. Robert Harrison, director of Occupational Health Services at UC San Francisco, that little is known about the long-term effects of benzene exposure on oil and gas workers, and that with the rapid expansion of oil and gas production in the U.S., the risks posed by benzene are ones “that we would want to pay attention to.”
About two weeks ago, eight conservation biologists from various organizations and institutions that the exponential growth of the fracking industry in the U.S. has vastly outpaced our understanding of its environmental impact. In addition, they identified threats that include surface and groundwater contamination, diminished stream flow, stream siltation, habitat loss and fragmentation, localized air, noise and light pollution, climate change, and cumulative impacts. They call on scientists, industry, and policymakers to determine and minimize the effects of fracking on nature and wildlife.
We can all agree that it’s time to close the knowledge gap, establish research priorities, and clearly identify the environmental and health risks associated with fracking operations.
In the meantime, what can be done to avoid already ascertained risks, as for example those posed by defective wells that lead to methane contamination of drinking water? Jackson : “You need strong rules and regulations on well integrity. You need generous setbacks that protect homes and schools and water sources from drilling, sometimes farther than the drillers would want. You need enough inspectors on the ground to keep people honest and you need separation between the industry and the inspectors and you don’t always have that in the US.”