There is no getting around it. The fracing process comes with the possibility of contaminating surface water by spillage or an accidental release of fracking fluid from the waste pit. Then, there is the possibility of contamination from fluid escaping from abandoned or leaking wells. Natural gas leaks into shallow aquifers can also cause problems for drinking water.
In many cases, pinpointing the source and extent of the contamination is difficult because there is a lack of baseline data, according to Jennifer McIntosh, professor of Hydrology and Atmospheric Sciences at the University of Arizona. “There is an opportunity for the scientific community to provide guidance on the best analytical methods for evaluating fugitive gas leakage and fracing fluid or water contamination of groundwater,” she said.
This where isotope hydrology comes in. This is a field of hydrology that uses “isotopic dating to estimate the age and origins of water and of movement within the hydrologic cycle,” as defined by Wikipedia.
A paper by McIntosh and 14 others from leading universities explained how various isotope-hydrology techniques can be used to monitor the impact of fracing on ground and surface water. It also provided recommendations on which method to use in various circumstances and environmental conditions. The initial ideas for the paper came out of an International Atomic Energy Agency (IAEA) technical meeting.
The analytical tools being developed to provide information on contamination sources involve naturally occurring isotope tracers in hydrocarbons, high-resolution data sets of natural gases and associated fluids from surface to target reservoir, and incorporating noble gas geochemistry and microbiology into more traditional hydrogeological and geochemical approaches.
Some of the approaches for detecting fracing contamination can be applied to subsurface storage of carbon dioxide and nuclear waste disposal, McIntosh said.
The IAEA promotes the use of isotope hydrology, allowing national experts to identify and assess the availability of groundwater resources. Isotope tracers provide needed data on the origins and behavior of pollutants. The IAEA’s scientific databases help member states create wateruse policies.