Methodology For Probable Maximum Loss Calculation And Potential Implications of Acid Mine Water For The South African General Insurance Industry

• Nature of the gold deposits in the Witwatersrand has led to formation of 'basins' • As mines stop operating water flows into adjacent mines • Eventually the last mine in a basin will cease operations • Underground workings will flood • Water level continues to rise until it reaches the surface • Water is of poor quality owing to reactions with sulphide minerals forming iron-rich sulphuric acid