New research led by HAS Professor Jennifer McIntosh shows that fracking has less impact on groundwater than traditional oil and gas production methods which inject much more water underground than other petroleum-production methods.
High-volume hydraulic fracturing, known as fracking, injects water, sand, and chemicals under high pressure into petroleum-bearing rock formations to recover previously inacessible oil and natural gas. This method led to the current shale gas boom that started about 15 years ago.
"If we want to look at the environmental impacts of oil and gas production, we should look at the impacts of all oil and gas production activities, not just hydraulic fracturing. The amount of water injected and produced for conventional oil and gas production exceeds that associated with fracking and unconventional oil and gas production by well over a factor of 10," McIntosh said.
McIntosh and her collaborator, Grant Ferguson from the University of Saskatchewan, published their paper, Conventional Oil--The Forgotten Part of the Water-Energy Nexus, online in the June 30th issue of the journal Groundwater. Global Water Futures of Canada funded the research. GWF is led by the University of Saskatchenwan in partnership with the University of Waterloo, McMaster University, and Wilfrid Laurer University.
McIntosh and Ferguson looked at how much water was and is being injected underground by petroleum industry activities, how those activities change pressures and water movement underground, and how those practices could contaminate groundwater supplies. They found there is likely more water now in the petroleum-bearing formations than initially because of traditional production activities.
Oil and gas production activities can have environmental effects far from petroleum-producing regions with some studies showing that operating disposal wells can cause detectable seismic activitiy more than 90 kilometers away. There are thousands of active, dormant, and abandoned wells across North America; some are leaky or were improperly decommissioned providing possible pathways for contamination of freshwater aquifers. While there is little consensus as to the size of the problem, the potential environmental impacts in Canada and the U.S. are immense. A 2014 paper by other researchers suggests the state of Pennsylvania alone has at least 300,000 abandoned wells, many of them "lost" because there are no records of their existence nor is there surface evidence that an oil well was once there.
Read a more highly detailed account of their research in Mari Jensen's article, Fracking Has Less Impact on Groundwater Than Traditional Oil and Gas Production, on the UANews.org website.