A Canadian oil sands mine is demonstrating that water-capped tailings technology can be used to convert a former tailings basin into a lake similar in appearance and function as other regional lakes. Since 2014, Barr has been conducting monitoring and physical assessments of the fluid fine tailings in this demonstration pit lake. Our work includes using data generated from annual sonar surveys to determine the top of the tailings’ surface; estimating water and tailings volumes, water-cap depth, and rate of settlement; and annual reporting on changes over time. Tailings samples are periodically collected throughout the lake and submitted for physical laboratory testing. In addition, we are analyzing tailings characteristics to determine changes in various properties over time. In-situ geotechnical testing consisting of cone penetration tests and vane shear testing are also performed periodically to determine changes in the tailings consistency over time.
In 2015, Barr established a program to monitor shoreline erosion and has since performed annual assessments and program refinements. Elements of the program have included inspecting shoreline conditions, installing a wave gauge, using weather-station data to create annual “wind roses” with air-dispersion modeling, using a spectral wave-prediction model called SWAN to compute general wave characteristics, modeling local sediment transport and erosion, combining lake bathymetry for sonar survey and LiDAR topography, determining erosion rates over time, and preparing periodic reports and recommendations.