What was developed or tested
Laboratory validation informed two field mixtures: 35% tailings with waste rock and canga in the base, and 35% tailings with graded aggregates in the sub-base. Field response exposed deformation sensitivity in the sub-base.
What the evidence supports
A valuable field-scale counterpoint to laboratory pavement studies. The trial demonstrated constructability while identifying sub-base deformation as a limiting behaviour requiring mix and layer redesign.
Environmental and technical uncertainty
Large-volume road use can displace quarried material, but drainage, dust, geochemistry and long-term deformation must be controlled. The field result shows why laboratory compliance alone is insufficient.
Benefit-case screening lens
Potential value: Potential co-product revenue, reduced demand for virgin aggregate or binder inputs, local supply and avoided tailings storage.
Deployment constraints: Product specification, consistency, processing and binder demand, customer qualification, market volume, haulage distance and residual liability.
Question before applying elsewhere
Does the site-specific residue meet durability, leaching, production-control and applicable material-specification requirements at the proposed scale?