This article describes remediation options for wind-remobilised old tailings at an 81-year Pb-Zn-Ag mine in NW-Argentina. Long-term exposure of the dry surface of the older impoundments to wind led to spread of tailings over 2.5 km2. Scoping-level geochemical characterisation included grain-size analysis, ICP-MS whole-rock geochemistry, XRD mineralogy, ABA and SPLP tests, and sequential extraction. Results suggested that high Pb-Zn contents are restricted to remobilised waste material and no leaching to the underlying soil occurred. Thus, the thickness was the driving factor to define remediation options. For sectors with up to 0.3 m (22%), excavation and mobilisation was suggested. For thicknesses between 0.3 and 0.6 m (78%), re-vegetation without impermeabilization was considered the best option. For in-situ old tailings (0.1 km2), surface impermeabilization and re-vegetation was strongly suggested.
