Assess the importance of atmospheric deposition of contaminants as a contributor to ecological impacts of oil sands development and identify sources.

• Use snowpack measurements sampled across a gridwork to develop maps of winter-time atmospheric contaminant loadings for the region ~100 km from the major upgrading facilities

• Assess long-term trends in winter-time atmospheric deposition

• Determine the potential impact of wintertime snowpack mercury loads on tributary river water mercury concentrations (Spring Freshet) using Geographic Information System and hydrological modelling approaches

• Compare snowpack loadings to those obtained from precipitation monitoring and compare spatial patterns to PAC air measurements obtained from passive sampling network

All data are subjects of a publication containing method details, full QA/QC, interpretations and conclusions. Citations:

A. Dastoor, A. Ryjkov, G. Kos, J. Zhang, J.L. Kirk, M. Parsons, A. Steffen. 2021. Impact of Athabasca oil sands operations on mercury levels in air and deposition. Atmospheric Chemistry and Physics 21, 12783-12807.

L. Chibwe, D.C.G. Muir, Y. Gopalapillai, D. Shang, F. Yang, J.L. Kirk, C. Manzano, B. Atkinson, X. Wang, C. Teixeira. 2021. Long-term spatial and temporal trends, and source apportionment of polycyclic aromatic compounds in the Athabasca Oil Sands Region. Environmental Pollution 268A, 115351.

J. Culp, I. Droppo, P. di Cenzo, A. Alexander-Trusiak, D. Baird, S. Beltaos, G. Bickerton, B. Bonsal, R. Brua, P. Chambers, Y. Dibike, N. Glozier, J.L. Kirk, L. Levesque, M. McMaster, D.C.G. Muir, J. Parrott, D. Peters, K. Pippy, J. Roy. 2021. Ecological effects and causal synthesis of oil sands activity impacts on river ecosystems: water synthesis review. Environmental Reviews 29. Doi: https://doi.org/10.1139/er-2020-0082.

Y. Gopalapillai, J. L. Kirk, M.S. Landis, D.C.G. Muir, C.A. Cooke, C.A., A. Gleason, A. Ho, E. Kelly, D. Schindler, X. Wang, G. Lawson. 2019. Source analysis of pollutant elements in winter air deposition in the Athabasca oil sands region: A Temporal and Spatial Study. ACS Earth and Space Chemistry 38, 1656-1668.

W. Wasiuta, J.L. Kirk, P.A. Chambers, A.C. Alexander, F.R. Wyatt, R.C. Rooney, C.A. Cooke. 2019. Accumulating mercury and methylmercury burdens in watersheds impacted by oil sands pollution. Environmental Science & Technology 53, 12856-12864.

C. Manzano, D. Muir, J. L. Kirk, C. Teixeira, M. Siu, X. Wang, J.P. Charland, D. Schindler, E. Kelly. 2016. Temporal variation in the deposition of polycyclic aromatic compounds in snow in the Athabasca Oil Sands area of Alberta. Environmental Monitoring and Assessment 188, 542.

and

J.L. Kirk, D. Muir, A. Gleason, X, Wang, R. Frank, I. Lehnherr, F. Wrona. 2014. Atmospheric deposition of mercury and methyl mercury to landscapes and waterbodies of the Athabasca oil sands region. Environmental Science & Technology 48, 73747383.