Characterizing the Organic Composition of Snow and Surface Water in the Athabasca Region

• Main Authors: Gibson, J.J., Yi, Y., Cho, S., Birks, S.J., Hazewinkel, R.
• Format: Other/Unknown Material
• Language: English
• Subjects: envir; geo; Athabasca River; Snow River
• Online Access: https://doi.org/10.7939/R3MK6581Q; https://era.library.ualberta.ca/items/bed963fd-40e4-4ba1-8a80-8d639d3c8772

This pilot study was conducted by Alberta Innovates – Technology Futures (AITF) to characterize the composition of organics present in snow and surface waters in the Athabasca Oil Sands Region (AOSR) with the goal of identifying whether atmospherically-derived organics present in snow are a significant contributor to the organics detected in rivers and lakes in the region. This study is divided into two parts, each describing a different approach to characterizing the organics present in snow and surface waters. In Part 1, we interpret existing polycyclic aromatic hydrocarbon (PAH) concentration data, collected from various monitoring programs in 2011, to compare the composition of PAHs in snow and surface waters across the AOSR. In Part 2, we interpret new ultra-high resolution mass spectrometry analyses of snow and surface water samples collected in 2012 to compare the dissolved polar organics present in snow and surface waters in the Athabasca Oil Sands region (AOSR). The first approach applied in this study uses existing data from snow, river and lake monitoring programs conducted during 2011 which measured total (dissolved + particulate) PAH concentrations in snow and surface waters in the region. The 2011 dataset includes total (dissolved + particulate) concentrations for 34 parent and alkylated PAH species for 105 snow, 272 Athabasca River and tributary, and 3 lake samples. These data were compiled so that the composition of PAHs in the Athabasca River, its tributaries and a small number of lakes could be compared with that of snowmelt. The snow data show compositional differences between the PAHs present in snow sampled from areas closest to oil sands activities (i.e., near-field sites) and from more distant (i.e., far-field) snow sampling locations. Despite large concentration variations in snow along geographic gradients, the composition of PAHs are found to be similar among near-field sites, but change significantly at far-field sites. Both the near- and far-field snow samples have PAH compositions ...