Designing and Operating Backfill Systems on a South African Gold Mine

For effective backfilling, a system with the 13 features covered under the section: effective backfill systems, is required. Effective backfilling cannot be done with systems that are badly designed, outdated or overextended. But in cases where the requirements for effective backfilling are overlooked, the shortcomings of such systems may wrongly come to be regarded as limitations to the capabilities of backfilling per se. Mining is currently done to depths of 3500 m, and is to go deeper since the gold-bearing reef extends down to 4000 m and 5000 m below surface. Effective backfilling systems will be required at such depths, and with suitable design this can be achieved. Mining the narrow tabular orebody of a typical South African gold mine is described at the start of this paper, then cycloned backfilling is discussed in general, and its effectiveness (most of the fill placed in South Africa is cycloned backfill or ædeslimed tailingsÆ).