Mine Waste and Tailings Conference 2023 | Brisbane, Australia | 13–14 July 2023 342 Monitoring tailings storage facilities with muon tomography M A McLean 1 , F Scutti 2 , R Seikel 3 , S Krishnan 4 , C Webster 5 , S Collins 6 , C Goss 7 , S Palanisamy 8 , P H Panchal 9 , J Donovan 10 and A R Duffy 11 1. Fellow in Applied Geophysics, School of Geography, Earth and Atmospheric Sciences, The University of Melbourne, Parkville Vic 3010. Email: m.mclean@unimelb.edu.au 2. Postdoctoral Research Fellow, Swinburne University of Technology, Hawthorn Vic 3122. Email: fscutti@swin.edu.au 3. Senior Software Engineer, Swinburne University of Technology, Hawthorn Vic 3122. Email: rseikel@swin.edu.au 4. Senior Lecturer, Swinburne University of Technology, Hawthorn Vic 3122; mDetect Pty Ltd, South Yarra Vic 3141. Email: skrishnan@swin.edu.au 5. Senior Technical Officer, Swinburne University of Technology, Hawthorn Vic 3122; mDetect Pty Ltd, South Yarra Vic 3141. Email: cwebster@swin.edu.au 6. Research Associate, Swinburne University of Technology, Hawthorn Vic 3122. Email: scottcollins@swin.edu.au 7. Tailings Metallurgist, Prominent Hill, BHP, Adelaide Airport SA 5950. Email: craig.goss@bhp.com 8. Director, Manufacturing Futures Research Platform, Swinburne University of Technology, Hawthorn Vic 3122. Email: spalanisamy@swin.edu.au 9. Research Associate, Swinburne University of Technology, Hawthorn Vic 3122. Email: ppanchal@swin.edu.au 10. Entrepreneurship and Innovation Associate Professor, Swinburne University of Technology, Hawthorn Vic 3122; mDetect Pty Ltd, South Yarra Vic 3141. Email: jdonovan@swin.edu.au 11. AAusIMM, Pro Vice-Chancellor Flagship Initiatives, Swinburne University of Technology, Hawthorn Vic 3122; mDetect Pty Ltd, South Yarra Vic 3141. Email: aduffy@swin.edu.au ABSTRACT Tailings storage facilities present a global and growing challenge for mining companies. Tailings, the by-products of the processing plant, need to be carefully managed, as the tailings storage facility could present a potential risk to lives and livelihoods in the event of a collapse. Such collapses can lead to environmental impacts of significant and permanent damage to regions downstream. Consequently, real-time monitoring of the structural stability of such facilities is a significant opportunity for the safety and sustainability of active mine sites and legacy mines. To our knowledge, this paper explores the world’s first application of muon tomography to analyse tailings dam structures by mDetect Pty Ltd and Prominent Hill at the Prominent Hill Mine site in South Australia. We present a novel method and technology to investigate the inner structure of tailings storage facilities performed using muons, a natural source of radiation that can be used to take X-ray-like scans of large structures. Muon technology, therefore, offers a unique opportunity to provide deep structural insights into tailings storage facilities and potentially a platform from which future research can investigate the development of early warning systems for change detection. INTRODUCTION Large structures, such as Tailings Storage Facilities (TSF), represent a unique challenge to existing technology utilised within the mining sector due to their extensive physical scale and slow evolution over time. Therefore it is desirable for a TSF to be the subject of long-term monitoring with surface and intrusive testing for stability and liquefaction assessments, ideally over significant volumes of the site. Remote monitoring capability for tailings structures is currently available with detection systems such as extensometers, LIDAR, total station, taseometers, and seismic sensors, to name but a few, but their range and coverage of detection area are limited. Furthermore, contemporary techniques might also come with compounding issues such as background noise that inhibits detection ability, radiation licences that create barriers to deployment, and significant energy consumption of the systems which increase cost and restrict the longevity and flexibility of deployment.