IM 2019 August 19 | Page 62

SLOPE STABILITY MONITORING Last May 30 IDS GeoRadar also announced RockSpot, an innovative radar system able to locate, track and alert on rockfalls in real time A watchful eye Paul Moore reports on the latest in slope stability monitoring, the importance of which has again been highlighted by industry events et again, a pit wall collapse has highlighted the need for industry to apply the latest technologies in slope stability monitoring, after part of the pit wall at the KOV copper mine owned by Glencore collapsed in a southeast Congo killing what has been reported as at least 40 artisanal miners that were illegally working there. Not only that, the massive Vale Brumadinho iron ore tailings dam failure has really focussed mining majors on this type of technology. As an example of this, Anglo American is now using geophysical passive resistivity surveys to identify phreatic surface levels in tailings dams and identify any potential soft or unconsolidated zones. The group has run this technique across a large portion of its Major and High CCS rated dams as an additional check, to better understand the conditions of the structure. Anglo has also installed fibre optic cable technology into some of its tailings dams and will complete three pilot projects by the end of 2019, providing near real-time monitoring of strain, deformation and seepage in its dams. In some cases, satellite technology will be combined with fibre optic cable monitoring to complement the performance and behaviour of the structure. Finally, at the new Quellaveco copper mine that Anglo is developing in Peru, the company is taking further steps by introducing micro-seismic monitoring of tailings dam foundations using specialised sensors. “This technology will Y 58 International Mining | AUGUST 2019 provide high quality target monitoring of various structures in the dam body and the foundation, localising any potential movement. It is also aimed at the geological and structural features in the dams and their foundations. We believe this approach is a first for the industry in relation to tailings dams performance.” Reutech says safety & productivity can go hand in hand Speaking at the Electra Mining 2018 exhibition, Jan de Beer, Executive Manager of Reutech Mining, stated that the majority of the important players in the industry agree that it is essential for mining to become safer – but said it is also clear that productivity and profitability must increase. De Beer believes that it is achievable to increase both while creating a zero-harm environment, and that the increased implementation of modern technology can contribute to this drive. Fourteen years ago, a major mining group requested Reutech Radar Systems to address the safety risks relating to falls of ground in open pit mines. Two years later, in 2006, Reutech Mining was formed with the delivery of the first-generation Movement and Surveying Radar (MSR). The company has since then assisted global clients by providing advanced technology equipment that increases mine safety and supports an increase in productivity. “Reutech Mining delivers products that assist with the protection of the physical perimeter monitoring of mines, as well as other solutions that provide early warnings in terms of fall of ground in both surface and underground mines.” One of the biggest risks in surface mines remains the fall of ground from big open pit slopes. Reutech Mining’s latest MSR is its third generation slope stability radar and is used on six continents and in 27 countries. The company says it is the fastest scanning real aperture radar capable of detecting submillimetre movement up to 4,000 m away from the rock face. “The MSR also offers the most advanced alarm configuration options available on the market, and it operates in environmental conditions ranging from -50°C to +55°C. With data being available in near real time, the MSR is able to detect small and large areas moving on the mine slope – allowing its user timeously to evacuate equipment and personnel from potential fall of ground risk areas. There are Reutech Mining’s latest MSR (shown is a modular version) is its third generation slope stability radar and is used on six continents and in 27 countries