title: Acid deposition in the Athabasca Oil Sands Region: a policy perspective.
abstract: Industrial emissions of sulphur (S) and nitrogen (N) to the atmosphere associated with the oil sands industry in north-eastern Alberta are of interest as they represent the largest localized source in Canada (with potential for future growth) and the region features acid-sensitive upland terrain. Existing emission management policy for the Regional Municipality of Wood Buffalo, where the industry is located, is based on a time-to-effect approach that relies on dynamic model simulations of temporal changes in chemistry and features highly protective chemical criteria. In practice, the policy is difficult to implement and it is unlikely that a scientifically defensible estimate of acidification risk can be put forward due to the limitations primarily associated with issues of scale, chemical endpoint designation (selection of chemical limit for ecosystem protection from acidification) and data availability. A more implementable approach would use a steady-state critical load (CL) assessment approach to identify at-risk areas. The CL assessment would consider areas of elevated acid deposition associated with oil sands emissions rather than targeted political jurisdictions. Dynamic models should only be (strategically) used where acidification risk is identified via CL analysis, in order to characterize the potential for acidification-induced changes that can be detrimental to sensitive biota within the lifespan of the industry.
authors.affiliation: Global Institute for Water Security, University of Saskatchewan, 117 Science Place, Saskatoon, SK, Canada, S7N 5C8. colin.whitfield@usask.ca.|Centre for Hydrology, University of Saskatchewan, 117 Science Place, Saskatoon, SK, Canada, S7N 5C8. colin.whitfield@usask.ca.
authors.forename: Colin J
authors.initials: CJ
authors.lastname: Whitfield
authors.affiliation: Environmental and Resource Studies, Trent University, 1600 West Bank Drive, Peterborough, ON, Canada, K9J 7B8.
authors.forename: Shaun A
authors.initials: SA
authors.lastname: Watmough
mesh_terms: D000143:Acids / Q000032:analysis; D000393:Air Pollutants / Q000032:analysis*; D000416:Alberta; D017753:Ecosystem; D004784:Environmental Monitoring / Q000379:methods*; D058735:Environmental Policy / Q000639:trends; D008962:Models, Theoretical; D009589:Nitrogen Oxides / Q000032:analysis; D061329:Oil and Gas Fields; D012989:Soil Pollutants / Q000032:analysis*; D013458:Sulfur Dioxide / Q000032:analysis
chemical_list: D000143:Acids; D000393:Air Pollutants; D009589:Nitrogen Oxides; D012989:Soil Pollutants; D013458:Sulfur Dioxide
keywords: Acid; Atmospheric deposition; Base cations; Critical loads; Dynamic modelling; Policy; Soils