In work supported by the National Science Foundation, researchers have identified new tracers that can identify fracking fluids in the environment, and even differentiate fracking flow-back water contamination from pollution caused by other types of oil and gas wells.
It turns out poor fracking operators leave their 'fingerprints' at the scene of their crimes. The 'fingerprint' in this case takes the form of specific profiles of boron and lithium enrichment as the fracking water comes into contact with boron- and lithium-rich clays 1 to 2 miles below the surface.
"This new technology can be combined with other methods to identify specific instances of accidental releases to surface waters in areas of unconventional drilling. It could benefit industry as well as federal and state agencies charged with monitoring water quality and protecting the environment."
The method is superior to the current use of organic molecules as tracers, because the boron and lithium do not degrade over time, leaving a lasting record of the source of contamination related to fracking. Also, the boron and lithium tracers do not depend on operators to add them to the injected fluids in the first place, making the method more reliable for enforcement purposes.
The scientists took their hypothesis into the field, testing 39 samples from Pennsylvania and Arkansas, and a West Virginia spill. One of the samples came from effluent of a wastewater treatment plant that had already treated and cleaned up the fracking wastewater -- proving that the method works even on highly diluted samples. The researchers claim that the "boron isotope geochemistry can be used to quantify small fractions (∼0.1%) of HFFF in contaminated fresh water" (HFFF is hydraulic fracturing flowback fluids).
A recent study suggests that fracking contamination can be avoided, if wells of high quality are properly maintained. Having a forensic method of catching the bad actors with their hands in the cookie jar will further help to enforce best management practices on well operators.
The paper, New Tracers Identify Hydraulic Fracturing Fluids and Accidental Releases from Oil and Gas Operations, is published in Environmental Science & Technology.