Mine Tailings Storage: Safety Is No Accident

Driving forces for tailings management The 2001 ICOLD report and subsequent research have illustrated that both chronic and catastrophic tailings storage-facility failures are preventable – caused not by a lack of technical knowledge but by management failures. As demonstrated by the Mount Polley and Samarco case studies, even failures relating to natural events, such as rainfall or earthquakes, or technical faults such as overtopping can reflect a flawed design or management failure. Acknowledging that technical solutions are site-specific, the driving forces identified below relate to management approaches that frequently contribute to technical failures.

Stakeholder risk and reward ratios As identified in chapter 5, the various stakeholders in a mining project are exposed to different risks and experience different degrees of benefit from and control over the operation. The interests of shareholders are generally prioritized and do not account for the potential losses that could result from a failure. This has the potential to produce poorer outcomes for other stakeholders. The McArthur River mine in the Northern Territory of Australia provides a salient example (Mudd 2016). There, successive mine expansions have led to chronic

leaching of acid, metals and salts from the tailings storage facility and waste rock dump, causing tailings storage-facility fires and contamination of the local river system. With a series of government approved mine expansions overlooking or undervaluing the cultural and environmental values identified by local indigenous communities. An international industry with local impact Many of the essential decisions that govern tailings storage- facility performance may be made by remote decision makers

The mouth of the Doce River on the Atlantic coast – the tailings plume five days after the Samarco disaster.

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