GEOSCAN Search Results: Fastlink


TitleIsotopic evidence for oil sands petroleum coke in the Peace - Athabasca Delta
AuthorJautzy, J J; Ahad, J M E; Gobeil, C; Smirnoff, A; Barst, B D; Savard, M M
SourceEnvironmental Science & Technology (ES & T) vol. 49, 2015 p. 12062-12070,
Alt SeriesEarth Sciences Sector, Contribution Series 20140458
PublisherNational Academy of Sciences
Mediapaper; on-line; digital
File formatpdf
AreaFort Chipewyan; Lake Claire
Lat/Long WENS-111.5000 -111.0000 58.7500 58.5000
Subjectsenvironmental geology; fossil fuels; isotopic studies; carbon isotopes; heavy metals contamination; hydrocarbons; aromatic hydrocarbons; Athabasca oil sands
Illustrationslocation maps; plots; tables
ProgramCoal & Oil Resources Environmental Sustainability, Environmental Geoscience
AbstractThe continued growth of mining and upgrading activities in Canada's Athabasca oil sands (AOS) region has led to concerns about emissions of contaminants such as polycyclic aromatic hydrocarbons (PAHs). Whereas a recent increase in PAH emissions has been demonstrated within around 50 km of the main center of surface mining and upgrading operations, the exact nature of the predominant source(s) and the geographical extent of the deposition are still under debate. Here, we report a century-long source apportionment of PAHs using dual (d2H, d13C) compound-specific isotope analysis on phenanthrene deposited in a lake from the Athabasca sector of the Peace-Athabasca Delta situated ~150 km downstream (north) of the main center of mining operations. The isotopic signatures in the core were compared to those of the main potential sources in this region (i.e., unprocessed AOS bitumen, upgrader residual coke, forest fires, coal, gasoline and diesel soot). A significant concurrent increase (~55.0 perthousand) in d2H and decrease (~1.5 perthousand) in d13C of phenanthrene over the last three decades pointed to an increasingly greater component of petcoke-derived PAHs. This study is the first to quantify long-range (i.e., >100 km) transport of a previously under-considered anthropogenic PAH source in the AOS region.
Summary(Plain Language Summary, not published)
This study reveals the importance of an under-considered mining-related source of polycyclic aromatic hydrocarbons (PAHs) emissions in Canada's Athabasca oil sands region: petroleum coke (petcoke), a by-product of the upgrading of bitumen. The proportion of petcoke-derived PAHs, as identified by carbon and hydrogen isotopic signatures of phenanthrene, was shown to increase in the last two decades in a lake located around 150 km north of the center of oil sands mining operations. This implies a long-range (i.e., > 100 km) atmospheric transport of Athabasca oil sands mining-related organic contaminants to sites more distal than previously reported.