The extraction of pillars, largely by trackless mining methods, at Randfontein Estates Gold Mining Company (Witwatersrand) Ltd.

Abstract

This dissertation covers the strategy applied in extracting Gold ore from geologically disturbed areas with dips ranging from flat through to ±60°. A further complicating factor was that the reef thickness varied from around 1 meter up to 3,5 meters wide. This project covers the aspects from system planning and investigation of mining methods, the computer simulations of pillar dimensions and the predicted stress patterns. The project then proceeds to explain the mining methods applied aiid some reasons for having chosen these particular methods. The results of these mining operations are evaluated and comments are made on relevant matters. Some of the problems encountered are explained and finally some of the lessons learned are enumerated so as to assist ether persons who are faced with similar type of problems.