Remediation of water ingress to old gold workings linked to active mines

摘要

Grootvlei Proprietary Mines (Pty) Ltd is the last remaining operational gold mine in the East Rand Basin of the Witwatersrand gold fields. Mining in the East Rand Basin has been ongoing over the last 80 years, and the basin is now largely mined out. The mine is located in Gauteng, some 25 km east of Johannesburg. Grootvlei Mine currently dewaters about 75 Ml/day from its workings in order to maintain access to underground reserves, with the pump station located at a depth of 740 m below surface. The water is treated to remove primarily iron and is then discharged into the Blesbokspruit, which flows over the East Rand Basin. This discharge is in line with the conditions of the existing water use license issued by the Department of Water Affairs and Forestry (DWAF).