Arun Muhunthan is the Tailings Management Lead at ATC Williams and a geotechnical engineer with two decades of experience in tailings projects. He has project-managed a diverse range of tailings dam projects, including high-consequence category upstream raise projects in Australia.
Arun, how did you happen to start working in Tailings Management?
After completing a Master’s in Geotechnical Engineering in Sri Lanka, I moved to Dubai to work on high-rise building construction in a Quality Assurance role for two years. I then immigrated to Australia in 2006 to be with my wife, who was already living here after completing her studies at the University of Melbourne.
I was fortunate to secure a position with ATC Williams as a Geotechnical Engineer and immediately began working on Tailings Management projects, including the Rosebery Mine site in Tasmania. I’ve also worked across the entire life cycle on many commodity projects, including copper, gold, zinc, lead, uranium and coal.
I love geotechnical work, performing sophisticated analyses, characterisations and assessments to solve challenges. Advanced geotechnics requires me to apply all my knowledge, which is very rewarding.
What has been your career path to Tailings Management Lead?
I’ve had exceptional mentoring as a junior through to principal engineer, from Senior Principals such as Keith Seddon, Behrooz Ghahreman-Nejad and former ATCW Senior Principal Mark Dillon. I have spent many hours in Keith’s office discussing various projects and drawing on his knowledge over the years. The Rosebery site was under Keith’s guidance for many years, and much of the early innovation there is due to his input.
Alongside TSF work, I’ve become proficient in water dams, ash dams, dry stacking, unsaturated soil mechanics, closure design, and erosion modelling.
I was appointed Tailings Management Technical Community Lead in 2024, which means I am privileged to lead our large, multidisciplinary team of tailings and geotechnical engineers across Australia.
How has the Rosebery TSF project developed lately?
The most significant innovation has been our ability to extend the Tailings Storage Facility (TSF) for another 15 years by thinking differently to meet the client’s needs. The unique “step-in” embankment design was a conceptual idea we believed would hold up to testing, and the modelling confirmed this for us. Our advanced numerical modelling capacity was essential to perform the sophisticated analysis required to create a safe design that would not lose strength when built on top of the existing tailings.
I appreciate the clear and honest partnership we have with MMG as the mine owners. Our work is always reviewed by their in-house teams, but they have confidence that we will deliver solutions that meet their budget and time constraints. Dam safety is always at the forefront of our minds, and independent reviews are an essential part of our process.
What is it like being an Engineer of Record?
Being the Engineer of Record (EOR) for the Rosebery TSF is a position of immense responsibility. However, I know the site and its instrumentation inside out after working on it for almost twenty years. There have been a few times I’ve been woken in the middle of the night by false alarms, but each occurrence must be investigated properly according to procedures. Rosebery is the only site for which I am EOR, but I conduct internal reviews for many other sites. I also mentor two deputy EORs.
How do you keep progressing your professional development?
Professional development has always been important to me. I’ve been a committee member of the Australian Mine Waste Conference for the past three conferences, which host 500-600 people. We hold these conferences every two years, with the next one in Queensland in 2027.
I have published several papers, with a few more in the pipeline for submission to industry journals. Another goal on my list is to become a Chartered Engineer, and I’m supporting others on the team to do the same.
What do you do to unwind and destress?
I live in Doreen, surrounded by native trees and wildlife, which I enjoy. I am an avid gardener and am well known for my homegrown tomatoes, chillies and okra. Family time is a priority on weekends, and we do a lot of socialising at sporting events with our two young children. I love sport, especially cricket, and try to watch as many international games as I can. I also enjoy supporting the Geelong Cats in the AFL.
