The potential to reduce the risks posed by tailings dams using satellite-based information

Abstract

The failures of tailings dams, used to store waste from mining operations, pose a significant risk to the health of people and the environment, especially in many low income countries where the extractive industry makes a significant contribution to the nation's wealth. Recently the rate of failure of tailings dams has increased. The demand for raw materials and increases in intense rainfall as a result of climate change will exacerbate this issue in the future. The monitoring of tailings dams is essential to reduce their probability of failure. Virtually all the recent tailings dams failures were preventable. However, there is generally a lack of transparency and accountability for these structures by mining companies. In the past 10 years an increase in the global coverage and accuracy of Earth Observation (EO) based information has made it technically possible to use EO-based data to remotely monitor critical aspects of tailings dams, such as their deformation and the leakage of pollutants. This paper describes the development of an EO-based service, being piloted in Peru, which would allow tailings dams to be monitored cost effectively, and also help to forecast any potentially risk inducing behaviour from tailings dams several weeks in advance. Many regulatory bodies in low income countries do not have the resources to adequately monitor mining operations. A low cost EO-based system could improve the transparency and safety of tailings dams, allowing timely preventative interventions to be made where the probability of failure is found to be high.

DAMSAT: An Eye in the Sky for Monitoring Tailings Dams

“…piezometers, drain flow meters; Lumbroso et al 2019). However, the rate of failure of tailings dams owned by large mining companies has remained constant, or in some parts of the world increased in the past 20 years, despite there being no obvious barriers for these firms to use the best available monitoring techniques (Lumbroso et al 2019).…”

“…There are also a very large number of small, unmonitored operating and non-operating tailings dams (Lumbroso et al 2019). In the past 30 years, there has been an increased number of mines operating on low profit margins by less experienced and less financially stable miners.…”

“…This often prevents effective government and third-party evaluation of the environmental risks posed by mines (De Carvalho 2019;Franks 2015). Governments also face the challenge of overseeing many mines, often in remote locations, with limited numbers of staff, who are often less experienced than those employed by the mines they are regulating (Lumbroso et al 2019).…”

“…In 2001, the International Commission on Large Dams (ICOLD) criticised the mining industry's record on tailings dam failures (ICOLD 2001); however, in the past 20 years the number of significant tailings dams accidents has remained high. A spate of catastrophic tailings dam failures in recent years have killed thousands of people, done great environmental harm, and damaged people's livelihoods (Lumbroso et al 2019). On 25 Jan. 2019, the Barragem 1 tailings dam, which stored 11.7 million m 3 of tailings at the Mina Cόrrego de Feijão in the Minas Gerais region of Brazil, failed, resulting in the deaths of about 300 people and the pollution of hundreds of kilometres of river downstream of the site (Cambridge and Shaw 2019;Vergilio et al 2020).…”

“…There are also thousands of abandoned tailings dams throughout the world. These are often the result of junior mining operations, which if they do not "strike it rich" before their debt is due, may have no choice but to file for bankruptcy and abandon their mining operations, leaving a legacy of "orphaned" tailings dams (Lumbroso et al 2019). There is also some evidence to suggest that the data on tailings dam failures is incomplete, with many smaller accidents going unreported for a variety of reasons, including because mine managers are afraid of taking legal responsibility Chambers 2016, 2017;Davies 2002;).…”