Published: December 17, 2015
By: Earthworks et. al.
Dear Mr. Butler,
We recently learned that in response to the Samarco tailings dam failure, ICMM will conduct a global review of tailings storage standards and critical controls.
As you know, the Samarco spill was devastating. The company’s iron ore tailings impoundment catastrophically failed in the Brazilian state of Minas Gerais, blanketing a town with toxic mine waste. At least 13 people have reportedly died as a result, and hundreds more were evacuated. One of the co-owners of this mine, BHP Billiton, is a member of ICMM.
Tragically, the Samarco spill is just the latest in a series of mine waste disasters that have occurred over the past two years. In August 2014, the tailings dam at the Mount Polley mine failed, releasing 24 million cubic meters of tailings and supernatant water into the Fraser River watershed in British Columbia, Canada. Tailings containment failures at several mines in Mexico have killed livestock and cut off water supply to thousands of people.
These disasters are part of a worrying trend. In an analysis of all tailings dam failures from 1910-2010, Dr. David Chambers and Lindsay Newland Bowker found major failures are increasing in frequency and severity since 1960. They concluded that, compared to pre-1960 failures, a tailings dam failure today is more likely to spill more waste (at least 100,000 cubic meters, as defined by the study), and to kill people.
In short, more frequent tailings dam failures with more severe consequences are on the way -- unless industry and regulators act.
Therefore, in its review of tailings management standards, we call on the Council to:
- Select reviewers with both technical expertise and independence from industry
- Publicize and make transparent the review’s findings
- Ensure that recommendations are binding on ICMM members
- Commit ICMM members to a process for implementing the review’s recommendation
Finally, we call on ICMM’s review to integrate recommendations made by the Mount Polley Independent Expert Investigation and Review Report. This report, commissioned by the Canadian government and released in January 2015, represents robust and objective standards for tailings management.
We echo the recommendations made in the Mount Polley report, including:
- For new mines, a shift to “Best Available Technologies (BATs)” in tailings storage, including the following: “a) Eliminate surface water from the impoundment; b) Promote unsaturated conditions in the tailings with drainage provisions and c) Achieve dilatant conditions throughout the tailings deposit by compaction.”
- For existing mines, applying BATs to conduct dry closure of tailings impoundments. Mines should dewater tailings and pursue all alternatives to perpetual water covers.
- The appointment of Independent Tailings Review Boards to provide third-party advice on all phases of the tailings impoundment – design, construction, operation and closure.
One year ago, we thought that the Mount Polley disaster would serve as a wake-up call to the mining industry -- to ensure the enormous amounts of waste the industry generates does not pose threats to public health and safety. Unfortunately, as subsequent tailings impoundment failures demonstrate, it did not.
We urge ICMM to conduct a transparent review that will yield objective analysis and robust, binding recommendations for its members.