Life Cycle Assessment of Western Canadian Tight Oil Resources

In the past decade, Western Canada has seen the rapid growth of tight oil resource development, where the associated environmental impacts are still being understood. This study presents a comparative life cycle assessment (LCA) of 13 tight oil producing formations across British Columbia (BC), Alberta (AB), and Saskatchewan (SK). The 2017 oil-production-weighted average gasoline emissions intensity produced from tight oil in BC, AB, and SK (P10 to P90 ranges in the brackets) are 85.7 (83.3–88.4), 89.2 (84.3–138), and 111 (88.5–196) gCO2e/MJ-gasoline, respectively. Operational venting activities drive emissions intensities, particularly in SK. The emissions intensities of gasoline produced from the Montney (BC) and Montney (AB) formations are found to be some of the lowest in North America with averages of 85.7 (83.3–88.4) and 87.0 (84.3–91.0) gCO2e/MJ-gasoline. In 2017, an estimated 14.8 million tonnes of CO2e (MtCO2e) was emitted from upstream tight oil production activities (including preproduction, production, and transportation) in Western Canada. A spatiotemporal correlation shows that 1.3% of tight oil wells assessed over the period 2012 to 2017 were correlated to seismic events. Water use for hydraulic fracturing also demonstrates regionally dependent relative impact, as shown by impacts to water scarce regions of Southern AB and SK. While this analysis does not prove causation, it demonstrates LCAs can aid investigations on environmental trade-offs. The results show the complexity of relationships between physical characteristics, operational characteristics, and environmental performance metrics rather than point estimates of GHG emissions alone.