Advanced sorting technology helps recover value, extend mine life and reduce environmental risk
Amid growing pressure on global critical mineral supply chains, TOMRA Mining is helping operators transform mine waste into clean, usable and revenue-generating material through its TOMRA sensor-based sorting technology.
Across the mining industry, vast volumes of waste rock are stockpiled or transported long distances for disposal — creating significant financial and environmental burdens. At the same time, many sites import construction-grade aggregate for haul roads, tailings dams and plant foundations, particularly in remote regions where material transport is costly.
TOMRA’s solution addresses both challenges simultaneously.
Removing Acid-Forming Material at Source
Using X-ray Transmission (XRT) sorting, TOMRA’s systems analyze individual rocks and detect fine-grained inclusions such as sulphide minerals. High-density, acid-forming particles are ejected from the material stream, leaving behind low-sulphide, chemically stable rock.
The result is waste rock that can be:
- Safely stored with reduced long-term monitoring
- Reused in on-site infrastructure
- Sold as commercial aggregate
Because the sorting process operates on defined size fractions, coarse material can be retained without unnecessary crushing, preserving processing capacity for mineralized ore.
Crucially, sorting creates environmental certainty. Certified low-sulphide waste reduces future risk, simplifies permitting and strengthens closure planning.
Proven Results in Australia and the U.S.
At the Renison Bell operation in Tasmania, run by Bluestone Mining Tasmania Joint Venture, XRT sorting separates non-acid-forming (NAF) from potentially acid-forming (PAF) waste, allowing stable material to be placed directly into long-term storage.
At Kensington Mine in Alaska, XRT sorting recovers sulphide-bearing gold particles while rejecting low-density, barren diorite pebbles. According to TOMRA, 4,216 ounces of gold were recovered from pebble sorting in one year — representing nearly US$20 million in value at January 2026 gold prices — while still producing a clean waste stream.
Waste Rock as a Revenue Stream
At the Mt Carbine operation in Queensland, operated by EQ Resources, sorting has redefined waste economics.
By removing sulphides early, coarse barren material is repurposed as aggregate for road base and concrete products. The site generates approximately AU$5 million per year in revenue from aggregate sales alone, with company leadership noting the sorting machines have effectively paid for themselves multiple times over.
Similarly, at Wolfram Bergbau Mittersill in Austria, between 25% and 40% of run-of-mine material is removed as coarse waste through XRT sorting and reused for tailings dam roads, shotcrete and local aggregate supply.
Each tonne rejected before flotation reduces tailings volume, directly extending mine life where storage capacity is constrained.
A Shift in Mining Economics
Historically, mining has operated on a simple equation: ore produces profit, waste generates cost. TOMRA sensor-based sorting technology challenges that model by enabling operators to:
- Recover additional metal value
- Reduce environmental liabilities
- Extend operational life
- Develop parallel aggregate revenue streams
By removing sulphides and certifying waste rock as clean and stable, TOMRA is positioning waste not as a liability, but as a managed and monetized resource.
As the global demand for critical minerals rises, technologies that enhance efficiency while reducing environmental impact are becoming central to long-term mining competitiveness.

