Advances in mine dewatering design and monitoring at Tharisa chrome mine Rustenburg South Africa (2025)

Mark Roebert, Nathi Mntungwa, Moses Msitsini², Pieter Holtzhausen², Kym L Morton²
Tharisa Minerals, Rustenburg, South Africa
2KLM Consulting Services Pty Ltd, 22 Central Road, Sunrella AH, 1748, South Africa

Abstract
Tharisa Minerals is a chrome and platinum group metals (PGM) open-pit mine near Rustenburg, South Africa. The mine dewaters three pits and a planned underground mine. Historic workings under the mine’s active East pit also require proactive water
management to ensure safe mining operations.
Tharisa’s dewatering strategy integrates stormwater control, in-pit pumping (boreholes and sumps), and pit perimeter dewatering boreholes. Automated monitoring of water levels record success in meeting drawdown targets. Water reuse enables a phased approach to zero discharge.
Tharisa is a good example of pro-active dewatering design. There are valuable insights on dewatering for surface and underground transition mines.
Keywords: Chrome, Dewatering, Pit-Perimeter, Monitoring, In-Pit Pumping, PGMs

Citation: Roebert, Mark; Mntungwa, Nathi; Msitsini, Moses; Morton, Kym Lesley (2025): Advances in mine dewatering design and monitoring at Tharisa chrome mine Rustenburg South Africa. – In: Valente, T., Mühlbauer, R., Ordóñez, A., Wolkersdorfer, Ch.: International Mine Water Association Conference – Time to Come. – p. 831 – 836; Braga (International Mine Water Association).