Like many other things in life, when society finds an idea or technology that works well, we want to put focus on said innovation to make it even better – think, for example, of the development of the continuous mining supersection, the increased efficiency and capacity of haul trucks and shovels, even the evolvement of the longwall in coal operations.
The same has largely been true for mass mining and the growth of interest in caving methods over the last few decades, in particular. With the right conditions and mining factors, many operators have chosen these techniques to achieve greater production levels over a shorter period of time, or as an option for expansions.
As such, interest from the ground control and geological community has taken hold, as have their respective research efforts, and conferences on the topic, such as MassMin and Aus-Min, have grown in popularity.
Mass mining has been supersized, so to speak, by operators – especially those mining low-grade copper or polymetallic deposits – looking to increase returns and production, resulting in what the industry is now referring to as ‘supercaves’.
According to two top names in the segment, consultants Iain Ross and Chip deWolfe, these caves will generally range from 80,000t/d to 150,000t/d or more.
Another key figure in cave mining research, Gideon Chitombo of the University of Queensland’s Sustainable Minerals Institute, told Mining Magazine in 2015 that operators were talking about figures to the tune of 140,000 to 150,000t/d, even 200,000t/d from one cave. With those kinds of numbers, it stands to reason that there could be risks and obstacles – not just in methodology and design, but also from an environmental and capital perspective.
