High efficiency separations as new environmental forensics tools for water monitoring around oil sands and hydraulic fracturing activity

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In Alberta there is public concern that oil sands process water (OSPW) is leaking into the Athabasca River, and widespread hydraulic fracturing (fracking) activity in Western Canada has many stakeholders concerned about the security and quality of their drinking water. Unfortunately, trace analytical methods for detecting OSPW contaminants in environmental samples, or for characterizing fracking-fluid components are still in their infancy, and it is clear that water monitoring by today's analytical methods cannot provide conclusive answers about the safety of water. The challenge is that OSPW and fracking-fluids contain supercomplex mixtures of unresolved chemicals. Typical tailings ponds likely contain more than 1 million distinct chemicals, but today's best analytical methods cannot resolve these beyond 5000 broad groups. Further complicating things is that many of the same chemicals in OSPW are known to enter the Athabasca River naturally, because groundwater and rain permeate through oil-sands deposits at the banks of rivers and streams.Although long-lists of chemicals that may be in fracking-fluids are publicly available, many other chemicals in the industrial mixtures are considered proprietary, and to date no peer-reviewed reports have attempted to characterize the complex mixtures of organics in these water samples by non-targeted methods. Analytical methods are needed that can accurately characterize these chemicals while simultaneously differentiating between natural and industrial sources. Using a "demo" supercritical fluid chromatograph (SFC) from Waters Corporation, and by linking this to a ultrahigh resolution Orbitrap mass spectrometer through a long chromatographic column (1 m), highly efficient separations were demonstrated that can be used to profile water samples around oil sands development. We have also characterized thousands of novel species in fracking-fluid by Orbitrap mass spectrometry, but require an SFC system to separate the highly water soluble organic chemicals that cannot be separated by HPLC. Our demo period with the SFC ended in 2013 and we are unable to continue this work. We request a new SFC to develop important environmental forensic tools for Canadian water monitoring.