A recent study by the University of Arizona and the University of Saskatchewan reported the total amount of water injected and produced for conventional oil and gas production is greater than ten times that associated with unconventional oil and gas production.
Jennifer McIntosh, professor of hydrogeology and atmospheric sciences with University of Arizona, and Grant Ferguson, associate professor with the College of Engineering at the University of Saskatchewan, were involved in the research. "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," stated McIntosh. They looked at how much water was injected underground by petroleum industry activities, how those activities change pressures and water movement underground, and how those practices could contaminate groundwater supplies. Data from California, Oklahoma, Ohio, the Western Canada Sedimentary Basin and the Permian basin were gathered from various state agencies.
"What was surprising was the amount of water that’s being produced and reinjected by conventional oil and gas production compared to hydraulic fracturing," McIntosh said. "In most of the locations we looked at – California was the exception – there is more water now in the subsurface than before. There’s a net gain of saline water."
While state and provincial regulations vary in the areas studied, general observations can be made. "I think the general conclusions about water use and potential for contamination are correct, but the details are fuzzy in some areas," Ferguson stated. "Alberta probably has better records than most areas, and the Alberta Energy Regulator has produced similar numbers to ours for that region. We saw similar trends for other oil and gas producing regions, but we need better reporting, record keeping and monitoring."