By: Murray Macnab - Group Executive Technical Director at UMS Group

Almost everything humans consume is grown or mined. As far back as 40,000 years ago, people excavated the earth for its minerals, and today, our ever-expanding population continues to drive the demand for the raw materials required by manufacturers and fabricators to produce much of what we use in our daily lives.

Murray Macnab, Group Executive Technical Director at United Mining Services (UMS) and a shaft sinking expert with over 40 years of experience, says that historically the type of mining method was usually 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. 

“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,” says Macnab. “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. In shaft sinking for example, removing people completely from the shaft bottom while lashing operations, and limiting the numbers of people on the stage and in shaft bottom during other activities is the driving factor for almost all innovations.”

He adds that safety has improved to the extent that entire shafts can be sunk without a lost-time incident, as showed at their underground project in Botswana, where UMS has been operating for three years without lost-time incidents. The company has reached similar milestones on most of its projects.  

“This was unheard of as recently as a generation back,” comments Macnab. “These records are showing that underground mines can be developed safely, and accordingly 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 like UMS who 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.

“Globally, ore deposits are unique to each region and each orebody. 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. Underground mine access is what we specialise in and many of our senior management team have over 40 years of project and mining experience delivering large projects.

“UMS has the added advantage that we can also build the mine by supplying the shaft sinking, development and engineering contractors, project management and owners’ teams to bring the mine into production. This leaves very little opportunity for things to fall in between the cracks and gives the investors a greater surety of success and reduces the surprises and risks.”

Macnab further notes that 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. Through its UMS 1Worx offering, UMS can gather data from sensors installed on plant and equipment to prevent critical events. The data collected can also be used to improve efficiencies. 

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.

“Underground mining is becoming more scientific, more controlled and more automated every day, requiring fewer people underground, and therefore safety and efficiency are vastly improving. UMS is keeping up with this progress by continually innovating, adopting new technologies and adapting to meet stakeholders’ requirements. Mining is here to stay and underground mining is the future. That’s my considered opinion,” concludes Macnab.