Climate resiliency of a tailings management facility: case study of Mont-Wright mine

Abstract

ABSTRACT This study investigates the climate resiliency of the Mont-Wright mine tailings management facility (TMF) in Quebec, Canada, with a focus on tailings erosion and flooding. Ultra-high resolution (1 km) climate simulations of the global environmental multiscale (GEM) model, spanning the current (2001–2020) and future (2041–2060) periods, form the basis of this study. Comparison of GEM model outputs against gridded observation data suggests reasonable performance of the model in simulating TMF-relevant climate variables, giving confidence in the model. The analysis indicates potential increases in tailings erosion rates of up to 6% (0.01 g/m2s) for the future period due to elevated wind-induced shear stress. Floods, represented in terms of probable maximum flood, reveal future increases in magnitudes of up to 20% in summer/fall for durations of 12–72 h. Increases of up to 17% are projected for spring for the 72-h duration, with decreases noted for other durations due to precipitation efficiency reductions. The projected small increases in erosion rates, in absolute terms, are not deemed to be of any major concern. As for projected increases in flooding, Mont-Wright mine’s climate-change adaptation strategy, which is aligned with existing Quebec guidelines, seems reasonable to mitigate flooding impacts.