Development and use of hazard ranking system for abandoned mine entries: A case study of the mine shafts in Giyani and Musina areas of South Africa

Abstract Treatment of old mine shafts can be a tedious and costly process if not carefully planned and managed. This paper presents the work conducted with the aim of evaluating the risk of abandoned mine shafts in the Giyani and Musina areas to guide the work of their treatment. The method that allowed the ranking of physical and environmental hazards of the shafts together with their corresponding socio-economic concerns was developed and applied in this work. The results showed that the risks of falling into the shafts and the problems of ground movement were the major physical hazards and environmental stresses of the shafts. Based on the results of the study, it was concluded that in addressing the problems of abandoned mine shafts, priority should be given to mitigation strategies for the major hazards followed by those that prevent release of toxic gases and discharge of contaminated mine water by the shafts. The method used in this work is recommended for preliminary evaluation of the hazards of abandoned mines in developing countries which have many abandoned mine sites and limited resources to conduct their rehabilitation.