Integrated Surface Water and Groundwater Modelling for Oil Sands Reclamation
Integrated Surface/Subsurface Models in Support of Mine Closure Planning
Today's mine operator must consider a variety of complex, integrated systems when developing a mine closure plan that is sustainable from both an engineering and environmental perspective, thereby meeting their corporate expectations and those of regulators and the public. Forecasting the outcome of an engineering design with independent groundwater and surface water computer programs has acknowledged limitations, as the real systems under consideration include feedback mechanisms between the two domains that can be critical in determining overall temporal behavior of the proposed closure design. Numerical approaches which attempt to loosely couple existing surface and subsurface computer codes are often problematic due to the complex, non-linear nature of the governing equations; and (at times) the simplifications necessary to reach stable numerical solutions may compromise the understanding of the real processes involved. An alternative approach, presented at Mine Closure Solutions, 2014, is to use integrated, physically-based numerical models to solve coupled groundwater and surface water flow equations simultaneously; using real-world mine closure examples to illustrate how this approach has been used successfully to understand (and forecast) the future behavior of such systems. Example applications include the sustainability of sensitive peat fen ecosystems and wetlands in a reconstructed environment that is subject to the pressures of a chaotically changing climate; and proof-of-concept for maintaining saturation in a co-disposed waste rock and tailings impoundment at a former pyrite mine.