Fen creation in the post oil sands landscape: Phase 2

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In Northern Alberta, where oil sands are extracted, open pit mining covers an area of ~895 km2, and peat dominated wetlands fed by groundwater, mostly fens, cover about half of this area. Industry is required to return the landscape to equivalent functionality. This means that functioning wetlands must be returned to the landscape as part of their landscape reclamation effort. An experimental fen system was constructed, along with the entire watershed that is required to generate groundwater flows that sustain an appropriate level wetness in the fen peatland. This system, the Nikanotee Fen Watershed, was constructed of overburden stripped to access the oil sands, and processed materials including tailings sands and petroleum coke, with construction completed in January 2013. The goal was to construct a self-sustaining ecosystem that accumulates peat, is capable of supporting a representative assemblage of plant species, and is resilient to normal periodic stresses such as those associated with climate variability. The system was designed and constructed using the best knowledge available at the time. Our initial assessment (2013-2017) showed the system remained wet under moderately dry conditions, was carbon accumulating, and had plants that included those found in nearby natural systems. It also showed the system was undergoing rapid change as soils and vegetation developed. The focus of this proposal is to evaluate the nature and extent of those changes, and use them to predict how the system will function in the future. For this we will continue to study how this system functions, and how this compares to nearby natural sites To predict future behaviour we will develop mathematical models, which must be constrained with parameters measured in the field. We will also use models to refine designs that can function with more efficient use of material and resources, as well as recommend where and how to place these wetlands in the final closure landscape, after a mine lease is completed.