Dam portfolio ORE2_Tailings support for decision makers follows-up on a prior example. We will show how to interpret the graph we present in that prior post. Dams probabilities of failure and ORE2_Tailings benchmarking at portfolio level. The portfolio of ten dams is displayed on the annualized probability of failure graph, together with the world-wide benchmarks. This graph shows dams: AA1 entirely under the benchmark range, AA3 straddling the benchmark range (uncertainty on the worse case pf estimate slightly above benchmark),…
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We are learning that structural integrity of hydro dams is also becoming an issue. Thus, similarly to tailings dams, we need a strategic operational and tactical planning for tailings hydro dams! Karl Terzaghi, American Society of Civil Engineers, “Terzaghi Lectures, 1974-1982,” American Society of Civil Engineers (1986) ISBN 0-87262-532-X. proposed that a dam rating system should provide ALL of the following: A logical framework for rating the relative safety of a dam Allow for the use of judgment and experience…
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Most tables of risk comparisons in the literature contain a mix of risks characterized by different levels of uncertainty. In addition, most risk comparisons in those tables offer only single number risk estimates, with no range or error term. For risks such as driving, where fatalities can be counted on large samples, the number is likely to be reliable, at least in some countries. However, even if the risk comparison data are carefully and accurately reported, they can be misleading.…
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Nosso Senhora do Livramento in Mato Grosso, Brazil is an example of tailings dam failure and risk confusion. The dam failure reportedly injured two. Available optical imagery showed a rather contained spill in a flat area at the toe. What we know on the Nosso Senhora do Livramento in Mato Grosso tailings dam At failure, the structure was reportedly 15 m high with a storage volume of 580,000 m³. The material released by the dambreak spread up to 2km downstream.…
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