A Comprehensive Review on Reasons for Tailings Dam Failures Based on Case History
Figure 1 --- Number and types of tailings dam failures in several countries.
Abstract
On a global scale, the demand for mineral products has increased substantially with economic development. Consequently, the mining of mineral resources results in the production and accumulation of a large number of tailings, causing many problems with respect to mining, the environment, and the economy. In the mining process, tailings must be reasonably treated to prevent them from entering the water cycle through rivers. The storage of tailings under water can effectively hinder the chemical reactions that they undergo. Therefore, it is a critical practice to store these substances in ponds or impoundments behind dams. However, tailings dams frequently fail, resulting in the discharge of significant quantities of tailings into the natural environment, thereby causing grievous casualties and serious economic losses. This paper discusses reasons including seepage, foundation failure, overtopping, and earthquake for tailings dam failures and explores failure mechanisms by referring to the available literature. This research has determined that the failure of tailings dams is closely related to the state of the country’s economy. Most of the tailings dam breakages in developed countries occurred decades ago. In recent years, the proportion of tailings dam failures in developing countries has been relatively high. Considering the serious damages caused by tailings dam breakage, it is important to understand the main reasons and mechanisms for their failure. The purpose of this review is to provide a reference for the design and construction to the building of the tailing dams and to reduce the occurrences of their failure.
2. Reasons and Mechanisms for the Current Tailings Dam Failures
On a global scale, there have been many severe accidents related to tailings dams. This paper summarizes the data on more than 300 events that have been collected and categorizes the reasons for tailings dam breakages into four root causes [21, 28–30]. Key examples of tailings dam failures are summarized in Table 1, including basic information about the tailings dam failures including dam height, dam type, and fatalities. Tailings dam can be divided into four categories according to their construction methods [64, 65]. Figure 1 counts the number and types of tailings dam failures in several countries. North America is the largest region in the world for tailings dam accidents. The failure of tailings dams is often caused by multiple factors and, in essence, is due to the influence of the external environment, for example, through increased loading of the tailings dam, earthquakes, rainfall, floods, and dam foundation subsidence [32, 57, 66, 67].
Source & rest of article -- https://www.hindawi.com/journals/ace/2019/4159306/
