Iain Struthers

Revegetation of gold residues in the eastern jarrah forest in the south-west of western Australia

Revegetation of mine residues (tailings) is an important aspect of rehabilitation after mining, and represents a substantial investment. Therefore it is important to increase our understanding of all aspects of re-establishing a sustainable vegetation community on these materials. We report here on a multi- disciplinary, collaborative research program, focusing on vegetation establishment, soil development, and water-balance modeling on a large residue revegetation experiment. The study focused on gold residues produced at the Boddington Gold Mine (BGM) and Hedges Gold Mine (HGM), in the south-west of Australia. The residue storage areas will be rehabilitated once no longer required, but revegetation may be hampered by the alkaline, saline, and sodic properties of the residue. A large field experiment was established to examine soil amendments and capping strategies. The treatments were three depths of gravel-rich subsoil (0 cm, 15 cm, and 30 cm) overlying residue treated with gypsum (30 t/ha). All plots subsequently received an application of topsoil (10 cm). The plots were established in 1999 with species from the local jarrah (Eucalyptus marginata Donn. ex Smith) forest, or salt- and waterlogging-tolerant native species.