ORE2 Tailings deployment steps: 5.1 Failure definition We designed ORE2_Tailings™ to support RIDM for tailings dams portfolios reliability enhancements. One achieves reliability by reducing failure likelihood to a certain level, and risks are tolerable. Thus it is necessary to clearly state what one considers the success of a structure within the portfolio. Indeed, unless we clearly define success, failure remains an ambiguous term. ORE2_Tailings™ considers a dam successful if it: stands as built and does not break allowing for…
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SLM and the probability of failure of a tailings dam goes back 35 years. A paper entitled “Probability and Risk of Slope Failure” (Silva et al., 2008) proposed using quantification of expert judgement. That is a subjective/semi-empirical probability evaluation as a practical alternative for determining probability of slope failure. We call this approach SLM, using the initials of the authors. SLM culminates with semi-empirical relationships between Factor of Safety -FoS- and probability of failure -pf-. That relationship allows to estimate…
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Dam monitoring effect is a case history. A client acquired a mining properties portfolio. It included inactive dams at closed mines. Some of these structures were relatively well documented, while others were not. As a result, the client was facing important decisions, one of them being the effort to enhance the knowledge on the structures. The question the client asked was: “What happens to a particular dam if the level of knowledge we have on an inactive dam goes from…
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The Oroville Dam Spillway Incident Report became public in January 2018. The story it tells is remarkably similar to the one we assumed, based on publicly available information in the aftermath of the accident. As risk advisers and managers we discuss below the various statements in the Oroville Dam Spillway Incident Report. We aim at highlighting risk biases and potential management changes to avoid similar developments. Oroville Dam Spillway Incident Report Conclusions Commented The Independent Forensic Team Report made a number…
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Utilisons les glissements de terrain comme un exemple, mais il y en a tant d’autres... De nombreux glissements lents actifs (en mouvement quasi continu allant de quelques millimètres par an à quelques décimètres par an) sont connus et repertoriés dans l’arc alpin. Ces phénomènes ont des impacts potentiels parfois très élevés tant au niveau de communautés qu’à celui de certaines industries (transports, énergie, tourisme) et font l’objet de programmes de recherché poussés. Un de ces glissement était déjà sous monitoring…
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