Deep Lead Mining - Is it Limited to the Past?

Deep lead mining by methods other thanconventional open-cut techniques has not been effectively employed in Australia in -the second half of this century. The reasons for this are essentially economic, and are related particularly to the labour intensive nature of the methods involved as well as the high consumption of support materials. These methods have been adapted in recent times to undertake bulk sampling programmes in deep leads. Although some consideration is given to surface-oriented hydraulic and solution mining applications, the prime function of this paper is to investigate the possible application of modern underground methods to deep lead exploitation. As deep leads are not currently being worked (with the exception of some minor operations on the Eastern seaboard), these applications remain essentially untested. They have, however, been conceptually developed following several years of small scale deep lead development. Current mineral economics, particularly with respect to gold, combined with the known extent of partially - or totally - unexploited mineralised leads demonstrates the necessity to investigate all possible means of ore extraction.