Seminar Abstract:
The Athabasca Oil Sands (OS) Region in Alberta Canada is home to one of the largest unconventional crude oil deposits in the world. Increased attention has lately been given to emissions of pollutants from the tailings ponds and their contribution to the total fugitive emissions from OS, including Volatile Organic Compounds (VOCs) and Total Reduced Sulfur (TRS) species. VOCs are of central importance in the atmosphere because of their close relation to air quality and climate change through the formation of ozone and secondary organic aerosols (SOA). Sources of VOCs from the tailings pond includes emissions from the residual bitumen from the tailings, evaporations from the organic diluent used in the oil extraction processes and the degradation of the oily films on the surface of the tailings. Additionally, with the accumulation of the tailings, hydrocarbons from the residual bitumen and diluent can stimulate microorganisms in the tailings pond to produce hydrogen sulfide (H2S) and other reduced sulfur compounds that are then released to the atmosphere. A comprehensive field study was conducted in the summer of 2017 on the shore of a tailings pond in an oil sand facility. Continuous high- resolution measurements of VOCs, TRS and H2S from a 32 m flux tower were combined with micro-meteorological methodologies to quantify fluxes from the pond to the atmosphere. Impacts of these emissions on Fort Mckay, a First Nations community located north of the Oil Sands facilities will be discussed.