Thamae, M & Nxumalo, M 2010, 'Challenges affecting structural stability in the design and construction of waste rock dumps at Nkomati Mine, South Africa', in R Jewell & AB Fourie (eds), Proceedings of the First International Seminar on the Reduction of Risk in the Management of Tailings and Mine Waste
, Australian Centre for Geomechanics, Perth, pp. 119-127.
Successful prevention of slope failures and management of the risk associated with potential failures in mine
waste rock dumps is accomplished by identifying factors affecting the dumps slope stability at different
stages of the mine development. Appropriate measures are applied at each stage as the extent of risk is
understood. As opposed to many mines in South Africa where the impact of factors which adversely affect
waste rock dump stability are usually limited, Nkomati Mine is located in an area where waste rock dumps
have had to be sited at the most unfavourable conditions. This paper describes challenges that have been
identified during the feasibility and design stages and how they are dealt with during the construction and
monitoring of the dumps. The paper highlights the use of geological models on the material zoning within the
rock dumps and the obstacles associated with insufficient data during field investigations. Further, it
discusses the seemingly divergent challenges faced by the technical staff and operational management,
where technical staff invariably tends to recommend conservative risk control measures while the
management is understandably interested in optimising returns. Furthermore, the challenges of constructing
dump walls whilst also focussing on mine production issues are also highlighted.
British Columbia Ministry of Energy and Mines (2005) Design and Operation of Large Waste Dumps – Version:
October 05 2001.
Geotail CC (2009), Design Report: Phased Development Plan for Waste Rock Dump, MMZ & PCMZ Low Grade Ore
Stockpiles and PCMZ Ore Stockpile at Nkomati Mine, December 2009.
Golder Associates Africa (2010), Final Report - Consolidated Geotechnical Services at Nkomati Mine, January 2010.
Challenges affecting structural stability in the design and construction of waste rock dumps M. Thamae and M. Nxumalo
at Nkomati Mine, South Africa
128 Mine Waste 2010, Perth, Australia