Reclamation Challenges and Environmental Stewardship

The low-hanging fruit having been mined for years, the trend of going underground to exploit lower-grade ore bodies has strengthened in recent years, bolstered by a market hungry for Québec’s minerals. Couple this more expansive and demanding way of mining with several assets nearing the end of life in Québec and operators are now dealing with issues like collapsing walls and increased extraction costs due to deeper mining.

Based on the observation shared by miners, engineers, and policymakers, tailings management has emerged as a pivotal concern in Québec's mining landscape. Indeed, tailings infrastructure represents a substantial risk due to the sheer scale in the Abitibi or Northern regions notably, and the potential consequences for both workers and local communities if they fail. Catherine Lajoie Fillion, president of engineering firm Go-Mine and the Canadian Dam Association, touched upon the state of the tailings infrastructure in the province: “Québec faces unique challenges stemming from its legacy of older infrastructure. Many facilities lack comprehensive documentation of their construction and geological contexts, complicating efforts to assess the integrity of existing dams and structures. This dearth of historical data introduces uncertainties regarding safety and environmental sustainability, necessitating careful regulatory oversight and proactive remediation measures.”

To tackle the challenges that aging infrastructure brings, Québec is therefore witnessing innovative ground improvement techniques at its legacy mining sites. Unstable soil can compromise the integrity of tailings dams and structures, and proper soil stabilization ensures that these facilities can withstand environmental stresses, reducing the risk of failures. Many facilities require substantial upgrades to meet modern safety and performance standards, driven in part by soil instability resulting from historical mining activities. The need for ground improvement solutions is increasingly urgent, and is exacerbated by environmental contamination from past mining operations. At the Kiena mine in Northern Québec, engineering group Menard employed deep soil mixing to stabilize tailings dams, ensuring stability in a seismically active area. In Meadowbank, Nunavut, the firm applied dynamic compaction to optimize the construction sequence of a diversion dam, using weights of up to 20 t dropped from heights of 20 m to achieve the desired soil compaction. Hubert Guimont, senior VP at Menard Canada, added: “Soil instability issues due to historical mining activities have led to increased demand for ground improvement solutions. Environmental contamination from legacy mining operations necessitates extensive environmental remediation efforts to ensure safety and compliance.”

In light of climate change, what is certain is that environmental restrictions will only get stricter globally. Another topic under increasing scrutiny from all stakeholders is water, and data from the government shared in February added fuel to the fire. For the first time, the Québec government lifted the veil of secrecy over its biggest industrial water users in a data dump that gathered decade-long records. Topping the list were none other than miners Rio Tinto and ArcelorMittal, with RT’s 2022 water use being enough to “fill 29,000 Olympic swimming pools”. As southern towns in Québec struggled with water shortage, and with that part of the province being increasingly opposed to mining activity, effective water management, community engagement, and adherence to environmental practices will be pivotal for mining operations to gain social license.