Satellite and IoT Solutions for Safer Tailings DamsBy Alejandro Ehrenberg | Tue, 06/16/2020 - 16:00
Tailings dams are one of the most conspicuous vestiges of mining operations. These repositories of waste material need constant monitoring to guarantee the safety of neighboring human and natural ecosystems. Traditionally, “tailings dams have been monitored using conventional in-situ geotechnical instruments, such as piezometers, inclinometers and prisms, and the instruments are often read manually by operators,” notes data scientist Rebecca O’Dwyer in an article for Medium. The COVID-19 outbreak and the mobility restrictions at mining sites resulting from it bring to the forefront the need for innovative monitoring techniques.
GRID-Arendal, a Norwegian NGO, has made a major contribution to tailings dams monitoring. The organization teamed up with the UN and the Swedish Government to create an online portal where “users can download data on more than 1,700 tailings dams around the world or sort and view it by location, company, dam type, height, tailings volume and risk classification, among other variables.” GRID-Arendal and its partners hope the portal helps to improve the mining industry’s waste disposal methods. Additionally, they want “governments to be able to use the data to make science-based decisions to better regulate the industry and improve public safety.”
Coeur Mining is one of the operators with assets in Mexico that has collaborated with GRID-Arendal’s database. The Chicago-based company has the Palmarejo tailings dam, located in Chihuahua, under its responsibility. Coeur Mining adheres to the highest international standards for tailings management. Its construction and surveillance methods result in comparatively safe dams. The company offers the following description of the site: “Palmarejo’s tailings dam is a downstream rockfill with the upstream face lined with HDPE and it is keyed to bedrock. Palmarejo tailings are classified as non-potentially acid generating and non-metal leaching. Prior to placement in the dam, the tailings undergo a detoxification process to reduce the cyanide concentration to below 5 parts per million. Tailings are deposited via a subaqueous slurry into a tailings impoundment. Any water discharged to the environment passes through a secondary inverse osmosis treatment plant to meet Mexico’s discharge requirements.”
Further innovative solutions for monitoring tailings dams are based on IoT and cloud computing. O’Dwyer explains that these technologies offer “real-time monitoring that provides granular data for determining the stability of a tailings dam. The ultimate outcome of using sensors and cloud computing is real-time three-dimensional deformation monitoring of tailings dams that is able to measure deformation with an accuracy of less than 1mm.” As reported by Mining Weekly, mobile satellite communications Inmarsat has launched an exciting IoT solution. “Tailings Insight allows users to view detailed information on more than 1,900 tailings dams, categorized by location, company, dam type, height, volume and risk, among other factors. It helps mining companies looking to improve data governance and transparency, removing many of the challenges related to data governance and ensuring visibility across global tailings portfolios in one place.”
As O’Dwyer concludes, collecting more data more frequently is key for the mining industry to improve its tailings dam monitoring techniques. Satellite and IoT solutions can help, especially if “sharing of data between mining companies is applied to developing modeling techniques faster.” The COVID-19 outbreak puts greater pressure on companies to implement innovative techniques and publicize their data.