Mine decommissioning: Environmental completion criteria for gold and nickel mine waste dumps in arid regions of Western Australia

摘要

The Western Australia Government Agenciescontrolling environmental bond assessment and landrelinquishment after mine decommissioning advocated proactiveenvironmental management. Meeting environmental objectivesensures return of bond monies and facilitates release of theCompany from environmental obligations. Completion criteriawhich confirm establishment of a self-perpetuating and resilientvegetation cover over mine waste are being developed.Quantitative assessment of ecological processes is the basis fordevelopment of completion criteria, and includes plant cover,revegetation density, species richness, and reproductive potential.Field sites are in arid (desert: summer and more effective winterrainfall) and semi-arid (semi-desert: Mediterranean) regions ofWestern Australia on Crown Land, with all but one being onpastoral (rangeland) leases. Post-mining land use generally revertsto maintaining the natural ecosystem or rangeland. Within thisclimatic zone very distinct vegetation communities are closelylinked to soil substrate classification. Matching surface wastecharacteristics from a mine waste dump with those of surroundinganalogue communities is the first step in determining anachievable vegetation cover.