Mine site construction, both above ground and far below, is a labour-intensive process requiring considerable expertise, planning, and strict adherence to safety procedures and protocols. Long before mines become fully operational, they must be designed. Above ground, there will be structures ranging from repair shops to cooling towers, buildings for administration, and more. Deep beneath the soil, shafts are planned, excavated, and reinforced, and underground infrastructure is created.
Underground mines are planned and carefully designed with the purpose of accessing, and extracting, minerals such as gold, silver, nickel, platinum, and many others. Productivity rates are calculated and include the number of shifts per day and calculations for equipment and labour required to meet specific goals. The overall mine site design and planning process encompasses various necessary criteria, such as detailed drawings, mine layout, development and production schedules, and cost estimates.
Historically, much of this planning was done by experienced engineers. As technology advanced and computers became smaller and less expensive, growth in mining engineering applications increased.
When constructing underground mine sites, many factors must be taken into consideration, including ventilation systems, ground support, drilling and blasting, equipment selection, dewatering, and stope sequencing, which is used to control the behaviour of rock mass in areas undergoing extraction.
Underground mine construction requires not only advanced computer software but highly specialized engineering expertise. Unlike open pit mining, underground mine planning and development must take ground support, the strength of the surrounding rock, ventilation, and other factors into consideration. Due to the complexity of underground mine design, engineers, designers, geologists, and planners are involved in the process. Everything from percentages of mineral bowls to be extracted and the design of the mine are considered. Pre-production planning, short and long-term planning are done to determine the size of mine and mill plants and how to maximize profitability while minimizing process time.
When designing and planning underground mines, construction both on the surface and below is required. Many mining companies will choose to contract a full-service underground mine construction and installation company. These businesses use the talents of seasoned designers, engineers, and construction specialists to provide a complete range of services from mine site conception and planning to design, commissioning, installation, and project handover.
New infrastructure development below ground at mine sites requires expert planning and must fully integrate functionality and safety considerations. Along with mechanical and electrical installations including heating, cooling, and ventilation systems, there are internal hoists, conveyance systems, chutes, waste bins, crushers, and more that are required.
Structurally, underground construction often sees the erection of below-ground shop facilities and refuge stations which are located wherever there is a possibility that workers cannot reach a mine exit in the event of a catastrophe, such as a fire. Refuge stations have been in existence since the 1930s, can be constructed in a variety of ways, are portable —able to be relocated from one area to another — or permanent, and are stocked with first aid equipment, fire extinguishers, and toilet facilities.
Many companies can handle the construction of both surface and below ground construction on mine site projects and can construct and install truck chutes, pump stations, fuel bays, underground garages and repair bays, escape-ways, latrine stations, hoists, cranes, dewatering stations, conveyors, and much more. Often, these same companies also design, construct, and install above-ground infrastructure like roads, garages, sewers, septic systems, drains, culverts, grading, and landscaping.
In late 2010, British-Australian multinational metals and mining giant Rio Tinto announced the creation of the Rio Tinto Centre for Underground Mine Construction (RTC-UMC). Reflecting a long-term commitment to engineering, science, and innovation, the company invested $10 million CDN over five years in the project. The global centre — created with world-leading researchers — was designed to focus on rapid mine construction and ground control for mining at depth and is located at the Sudbury, Ontario Centre for Excellence in Mining Innovation (CEMI). National not-for-profit CEMI is dedicated to innovation in exploration, deep mining, integrated mining engineering, and underground mine construction, and sustainability.
At the time, Rio Tinto’s General Manager of Underground Innovation Dr. Fred Delabbio said: “Our partnership with CEMI provides an opportunity to combine experts from the civil and mining industries. The centre’s research into high-speed underground mine construction will include implementation of mechanised tunnelling and shaft sinking systems, and CEMI will assist in the development of innovative support systems and in minimising the risks for such technologies.”
CEMI collaborates with both Canadian and global mining colleges, along with various levels of government, universities, colleges, and small to medium enterprises in the service and supply sector. Identifying, assessing, and managing research and business-lead programs such as the Innovation & Prosperity Office (IPO) and the Ultra-Deep Mining Network (UDMN) are among its initiatives.
With the added focus on underground mine construction, the centre has taken on research in support of Rio Tinto’s Mine of the Future™ program. Research includes exploration of rapid mine construction and effective ground control measures necessary for the development of underground mines. Among some of the RTC-UNC program initiatives are overseeing the development of innovative technologies used to improve the speed and quality of underground infrastructure construction; monitoring rock mass behaviour to reduce geo-risks; improving identification of strainburst (a spontaneous rockburst that occurs when rock can no longer contain the stresses upon it) potential; and advancing mechanized excavation programs for tunnel boring systems.
Through a combination of observational research and analysing relevant data from mines, the RTC-UMC is, “working to create next-generation technologies for mining operations that result in improved safety, greater efficiency, lower production costs, improved health and environmental performance with more attractive working conditions – all essential elements for the success of large-scale mining of the future,” according to the Centre for Excellence in Mining Innovation.
For underground mine sites to operate efficiently and safely, they must be designed by experts familiar with every aspect of site creation and construction from project planning to eventual mine closure years in the future. Multi-disciplined construction companies —installing mechanical and electrical components, ventilation, and constructing underground —provide the turnkey solutions that are essential to the entire process of underground mine development and construction. Services may even include financing in some cases. For mine companies, utilizing the expertise of one-stop construction specialists greatly reduces time and expense arising from seeking multiple firms to take on individual tasks. In many cases, these projects are also well-managed, which helps prevent scheduling conflict.
Mining engineers, geologists, and hydrologists are vital to safe and successful mine operation. So too, underground mine construction is a multidisciplinary team effort that relies on the strengths and skill sets of individuals who come together as a whole to create mines that operate as safely and effectively as possible.