Underground mining has become more scientific, controlled and automated, requiring fewer people underground, improving safety and efficiency.
While society has dictated that surface mining is no longer acceptable in many countries, it has also dictated that underground mining must be done safely.
Historically, the type of mining method has been determined by what the orebody could support economically.
If an open-cast pit mine could access an orebody, this was the preferred option as mining could commence relatively quickly, safely and economically compared to the time, risks and higher costs associated with developing an underground mine.
Consequently, there are more open-pit mines in the world, but several factors are prompting the growth of underground mining.
These include depletion of the accessible surface orebodies, environmental legislations to conserve and protect the landscape – with some countries now prohibiting open-pit mining – and significant progress towards zero harm in underground mining operations.
Mechanisation and automation
The need to mine safely and economically has challenged the underground mining methods used for the past century, which were labour intensive and often unsafe, partly due to a lack of understanding of geotechnical and geological conditions.
As a result, there has been a move to mechanise and automate processes where possible, particularly for repetitive work that does not require specialised input.
For example, in shaft sinking, removing people completely from the shaft bottom while lashing operations and limiting the numbers of people on the stage and in the shaft bottom during other activities is the driving factor for almost all innovations.
Improvement in safety
Safety has improved to the extent that entire shafts can be sunk without a lost-time incident, as shown at their underground project in Botswana, where UMS has been operating for three years without lost-time incidents.
This was unheard of as recently as a generation back.
These records show underground mines can be developed safely, and accordingly,y underground mining is being viewed in a better light.
Safety is considered non-negotiable by all stakeholders, and zero harm can be achieved by adopting new technologies, coupled with finding and managing the risks upfront in the design phase to mitigate or eliminate them.
This requires an in-depth knowledge of all factors on underground mine development, such as heat and ventilation, pollutants, personnel tracking, types of drilling machinery, rock bolting, blasting types, pumping and water sealing, to name just a few.
That’s why when developing an underground mine, it’s vital to partner with an experienced company that can supply all the front-end conceptualisation, designs, costing, schedules, financial planning, risk assessments, and social and legal requirements to compile it in a feasibility study that meets the investors’ requirements.
Digital solutions
Ore deposits are unique to each region and each orebody, and this makes for different types of underground mine designs requiring specialised knowledge of various orebodies, the capital required and schedules to mine the orebody most safely and efficiently.
It becomes complex and often overwhelming if your team is not experienced in engineering the best solution.
The company has partnered with a digital solutions provider to generate real-time as well as predictive and actionable data and information that can assist in sinking a shaft through to ultimately operating a mine in the safest and most productive way.
He explains that the combined data can help identify potential equipment failures, optimise maintenance schedules and reduce unplanned downtime.
The information is live and available anywhere around the world, allowing all involved teams to know the status of operations such as hoisting of rock, pumping of water, volatile gases, last blasts and next blasts.
The technology can also be used to automate activities such as completing log sheets of the processes happening underground while analysing any delays.
