Beca is redefining tailings with smarter waste management for modern mining.
As mineral operations target higher recovery rates from increasingly lower-grade and complex orebodies, mineral processing circuits are producing finer ore feeds to enhance mineral liberation.
This shift is resulting in a growing proportion of ultra-fine tailings – particularly those under 45 micrometre (µm) – which present significant challenges in handling, consolidation, and rehabilitation.
Due to their narrow particle size distribution and lack of larger particles, these tailings exhibit poor packing densities. This limits their ability to develop sufficient material strength, reducing opportunities for reuse and leading to continued reliance on traditional tailings storage facilities, in-pit disposal or low-strength underground backfill.
While dry stacking is gaining traction, its widespread adoption is constrained by cost, climate conditions (especially in tropical and wet environments), and the technical demands of dewatering large volumes.
Key risks in tailings management
As tailing volumes grow and environmental expectations rise, mining operations face increasing pressure to manage waste more responsibly. Several critical risks must be addressed to help ensure safe, sustainable and cost-effective tailings handling, storage and repurposing:
Escalating liabilities – large tailings storage facilities pose significant long-term risks, including community safety concerns, environmental degradation, and rising life-of-mine costs.
Limited repurposing potential – reusing tailings at scale is often constrained by factors such as distance from viable markets, difficulty in achieving sufficient material strength due to fine particle sizes, and the need to stabilise leachable constituents.
Brine management challenges – tailings and brine disposal are closely linked, particularly during mine closure. Effective management requires an integrated strategy that begins early in the mine’s life and continues through closure and monitoring.
Beca’s expertise
Modern mining operations are being met with rising expectations to reduce the environmental and community impacts of tailings. Key priorities include minimising surface tailings storage, improving long-term stability, and expanding opportunities for repurposing.
Beca brings leading expertise across the full tailings lifecycle, from identifying suitable geological and geotechnical conditions for storage facilities to mine closure and post-closure monitoring. The team designs optimal slurry characteristics tailored to the intended storage method, whether traditional slurry, paste, or filter cakes. It also develops backfill formulations, manages tailings dams and leads innovative repurposing strategies.
“What sets Beca apart is our pioneering work in tailings reuse,” Beca chief metallurgist Paul Language said. “We focus on enhancing mineral recovery and enabling the beneficial reuse of tailings both on-site and off-site, contributing to more sustainable and economically viable mining operations.”
Geotechnical, geochemistry and hydrogeology
The long-term stability of any tailings storage facility depends on selecting landforms with robust geotechnical characteristics. Given the extended operational life of these facilities, confidence in early-stage data is critical.
Beca offers deep expertise through a team of more than 160 geotechnical engineers, engineering geologists, and hydrogeologists across Australia, Southeast Asia and New Zealand.
“We deliver comprehensive studies to identify and assess suitable landforms for safe, sustainable tailings storage,” Beca minerals and metals segment director Tristan Musgrave said.
Optimising slurry for efficient handling
Slurry thickening and handling are central to effective tailings management, whether for traditional storage low-strength backfill or dewatering. With over 40 years of scientific and engineering experience, Beca understands the importance of slurry rheology in transport and dewatering systems.
“Our approach includes fundamental slurry testing to inform pump system design and dewatering to ensure project success,” Language said. “We design systems that accommodate variability in tailings feed, optimise water recovery, and reduce energy consumption, all key challenges for operators today.”
Filter cake dewatering, handling and storage
As demand grows for higher tonnages and drier filter cakes, equipment suppliers are scaling up and automating dewatering technologies. While pressure filtration is often the default technology, centrifugal and vacuum filtration can offer viable more cost-effective and higher-capacity alternatives.
Beca’s equipment selection process is grounded in strong relationships with vendors and test laboratories.
“We explore options such as modified drainage characteristics, staged filtering and slurry additives,” Language said. “Ultimately, the solution developed by Beca is a seamless system integration of dewatering, storage and conveying.
“Our differentiator in producing drier filter cake is the understanding of creating a durable drystack in tropical and wet climates, adding to the stability of landforms over time.”
Smarter tailings deposition for long-term stability
Tailings deposition can often be treated as an operational afterthought, leading to poor water recovery and inefficient use of storage capacity. This can create significant challenges during closure and long-term maintenance.
And that’s why Beca takes a proactive approach.
“Our hands-on approach to leveraging technical knowledge of rheology together with practical constraints of safety and operability of deposition systems is a key strength,” Beca market director resources and sustainable fuels Matt Kebbell said.
Unlocking value from tailings
Regulatory and environmental pressures are driving the need to minimise surface tailings storage and explore repurposing opportunities. Beca is at the forefront of developing high-strength applications for tailings, including concrete, building materials, and engineered backfill.
“Our innovation includes modifying particle size distribution through agglomeration and sizing, and separating particles in slurry form for use in high-consolidation applications,” Language said.
“These processes also enable the recovery of trace minerals, adding further value.”
Closure and environmental compliance
Mine closures are becoming more complex and costly, often exceeding planned budgets and timelines. With increasing commodity volatility and climate-related risks, early integration of closure planning is essential.
“Our multidisciplinary team of engineers, scientists and metallurgists embed closure strategies from the earliest design stages.” Musgrave said. “We provide ongoing operational advice and deliver closure solutions that address a wide range of technical scenarios, enabling compliance and long-term sustainability.”
Project management and delivery
Delivering technically challenging tailings projects requires deep insight and a balanced focus on immediate needs and long-term outcomes. Beca excels in managing complex brownfield projects, earning trust from regulators, communities and operators.
“Our project leads bring passion and experience, ensuring practical solutions that meet today’s challenges while preparing for future closure and compliance,” Musgrave said.
“With over 4500 engineers, planners, environmental scientists, project managers and commercial specialists, we’re ready to form the core of your tailings team, working alongside your in-house experts and other specialists.”
Case study
This project formed part of the requirement to secure permitting for a new mine and mineral processing plant, with a key condition: surface tailings storage to be minimised and no additional surface storage permitted beyond the first five years of operation.
The project was delivered in two stages:
Stage 1: A desktop study identified large-volume re-use options to reduce surface tailings storage.
Stage 2: Selected concepts were developed to pre-feasibility level, supported by laboratory testing.
The adopted solution included a portion of the tailings to be agglomerated and sized to achieve a coarse particle fraction which would result in an ideal packing density and hence high compacted strength.
The concept was tested by producing a “synthetic aggregate” from tailings that utilised a low-carbon, high-strength cement alternative (geopolymer). This was blended with the bulk of tails resulting in backfill mixes with high comprehensive strengths (greater than 4MPa). Geopolymer binders – made from industrial by-products – were activated with a basic solution. This matrix resulted in the total “non-tailings” material addition (binder) to the backfill of less than 15 per cent, a reduction of 40 per cent over traditional backfill tailings approaches.
The net benefit for the project was threefold: 70 per cent reduction in surface tailings storage; 90 per cent lower CO2 emissions from binder use; mine life extended by almost 50 per cent.
The project is now in final design and expected to move into execution in the near future.
This feature appeared in the November issue of Australian Mining magazine.
