Profiling oil sands mixtures from industrial developments and natural groundwaters for source identification.
The objective of this study was to identify chemical components that could distinguish chemical mixtures in oil sands process-affected water (OSPW) that had potentially migrated to groundwater in the oil sands development area of northern Alberta, Canada. In the first part of the study, OSPW samples from two different tailings ponds and a broad range of natural groundwater samples were assessed with historically employed techniques as Level-1 analyses, including geochemistry, total concentrations of naphthenic acids (NAs) and synchronous fluorescence spectroscopy (SFS). While these analyses did not allow for reliable source differentiation, they did identify samples containing significant concentrations of oil sands acid-extractable organics (AEOs). In applying Level-2 profiling analyses using electrospray ionization high resolution mass spectrometry (ESI-HRMS) and comprehensive multidimensional gas chromatography time-of-flight mass spectrometry (GC × GC-TOF/MS) to samples containing appreciable AEO concentrations, differentiation of natural from OSPW sources was apparent through measurements of O2:O4 ion class ratios (ESI-HRMS) and diagnostic ions for two families of suspected monoaromatic acids (GC × GC-TOF/MS). The resemblance between the AEO profiles from OSPW and from 6 groundwater samples adjacent to two tailings ponds implies a common source, supporting the use of these complimentary analyses for source identification. These samples included two of upward flowing groundwater collected <1 m beneath the Athabasca River, suggesting OSPW-affected groundwater is reaching the river system.
Water Science and Technology Directorate, Environment Canada, 867 Lakeshore Road, Burlington, Ontario, Canada L7R 4A6.
Richard A
RA
Frank
James W
JW
Roy
Greg
G
Bickerton
Steve J
SJ
Rowland
John V
JV
Headley
Alan G
AG
Scarlett
Charles E
CE
West
Kerry M
KM
Peru
Joanne L
JL
Parrott
F Malcolm
FM
Conly
L Mark
LM
Hewitt
D000416:Alberta; D004784:Environmental Monitoring; D008401:Gas Chromatography-Mass Spectrometry; D060587:Groundwater / Q000032:analysis*; D007220:Industrial Waste / Q000032:analysis*; D061329:Oil and Gas Fields / Q000737:chemistry*; D059392:Petroleum Pollution / Q000032:analysis*; D012822:Silicon Dioxide / Q000032:analysis; D013050:Spectrometry, Fluorescence; D021241:Spectrometry, Mass, Electrospray Ionization; D014874:Water Pollutants, Chemical / Q000032:analysis*
D007220:Industrial Waste; D014874:Water Pollutants, Chemical; D012822:Silicon Dioxide