In order to develop a Tailings risk assessment methods comparison we will start by: reviewing a number of existing alternatives to ORE2_Tailings™. This leads to justify the need for the ORE2_Tailings™ approach, discussing what we call the Blackbox objection, which actually applies to all the alternatives and finally the ORE2_Tailings™ procedure, algorithm and results. Alternatives to ORE2_Tailings™ We have grouped possible alternatives into four families discussed below. FMEA FMEA is not a quantitative risk assessment even if it uses indices…
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A colleague sent us a paper by Rana, Ghahramani, Evans, Small, Skermer, McDougall and Take. We reference it herein as Rana’s 2022 paper. The title is “Global magnitude-frequency statistics of the failures and impacts of large water-retention dams and mine tailings impoundments”. It is available online since Aug. 3rd 2022 at Earth-Science Reviews (2022), . I must confess at first I was quite intimidated. Almost a decade earlier we had written Factual and Foreseeable Reliability of Tailings Dams and Nuclear…
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Tailings dam mitigation risk informed decision making closes the discussion we presented in prior blogposts. We now focus on one dam and show how ORE2_Tailings™ supports rational and sensible risk mitigation decision-making as requested by GISTM. The dam case The dam we selected for this example is inactive and is parallel to a valley bottom. An unprotected creek runs at its toe and the bed is considered to be sufficient for the 1/500 return. Beyond that flood, there will be…
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Tactical and strategic planning for dam portfolio using ORE2_Tailings is the third of a series of blogposts explaining how to use ORE2_Tailings™ results. Indeed it follows: Dam portfolio ORE2_Tailings support for decision makers and ORE2_Tailings supports ICMM global industry standard on tailings management conformance. We use the same figures we have developed in those prior discussions. Summary of the portfolio ORE2_Tailings™ results With respect to probability of failure The portfolio of ten dams is made of two “bad apple” dams…
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Cobriza, Peru tailings dam failure occurred at Cobriza in Peru on July 10th 2019. Cobriza is a copper mine. Reportedly “the concentrator was operated at a rate quite below its capacity due to lack of mine ore and lately (2016 and 2017) due to lack of capacity in the tailings dam“. The plant is also subject to a highly controversial liquidation. Media invoke poor management as a cause of the failure. Google Earth image of the Cobriza mine tailings in Peru. The failed…
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How to bounce back from the Responsible Mining Foundation grim report with sustainable actions is a response to their statement: “Too often, workers, mining-affected communities, governments and investors are kept in the dark about the risks involved and how well companies are addressing these risks. Companies may be reticent to publicly reveal this potentially detrimental and sensitive information, yet it is workers and communities whose lives and livelihoods depend on adequate protection measures being in place”. Mining needs methodologies for…
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Last week we focused on technical aspects of the Risk analysis of dam break. This week we go further by looking at societal tolerance and approaches. These may integrate ethical and economical approaches to these studies. Probability of failure and bench-marking of the case history dam A recent study of a tailings dam (centerline, rockfill, well investigated, built and monitored) using the ORE2_Tailings app delivered an estimate of the probability of failure. The result was pf in the 10-4 to…
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Tailings dam portfolio screening level risk assessment is the title of our latest paper on this extremely interesting subject. The paper uses a case history to show how we helped management of a complex operation with a portfolio of dams to develop a risk management road-map. In addition uncertainties, incomplete information are always explicitly considered when we deploy tailings dam portfolio screening level risk assessment. Tailings dam portfolio screening level risk assessment The dam portfolio approach addresses managers who have…
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