Nov 4, 2020
Mining comes with inherent risk. As technology advances, intelligent sensors and automated data collection replace the manual monitoring of mining sites. This mitigates risk where safety is a priority and where the worksite conditions are challenging. Tailings impoundments (raised embankments and retention dams) present some of the most challenging conditions, in some of the most remote locations, on the planet. Manual monitoring of these sites is labour-intensive, weather-dependent, costly, slow, and prone to error.
“In the old days where everything had to be wired to data loggers,” Adrian Jonson, Business Development Agent with RST Instruments said. “The limitations it was bound to were restrictive.”
Measurand’s ShapeArray modernizes the mining industry’s monitoring strategy with easy-to-install, pre-calibrated sensors that gather precise ground deformation readings at a fixed cost. Modernized geotechnical instrumentation provides stakeholders with the ability to automate the collection of data and transmit that data wirelessly and remotely. Measurand’s ShapeArray paired with a DT ShapeArray wireless data logger node by RST Instruments can connect to the RSTAR Radio network to automate wireless data collection, viewing, and analysis. Automated data collection allows for the communication of accurate and timely measurements about what’s happening subsurface so your engineers can make better decisions based on better data.
“Going wireless has really changed everything,” Jonson said. “Right from being able to not have to string cables everywhere and worry about cable management, to being able to connect sensors that were so far away from anything reliable, that they can now be monitored regularly and in an autonomous fashion. Alerts become real and people can manage data more effectively.”
Automated data collection allows for the communication of accurate and timely measurements about what’s happening under and around some of the most challenging environmental conditions so your engineers can make better decisions based on better data.
Contaminated tailings dams store waste that can become unstable, moving horizontally or vertically as water pressure builds and seeps. These waste dumps can exist at high elevations and can span hundreds of square kilometres. Detecting changes in subsurface movement are imperative where a failure poses a high risk to the environment and infrastructure downstream.
The steep benched slopes of open-pit mines and the shafts of underground mines can experience surficial movement, instability, and failure if not carefully monitored for movement.
Each of these geologic conditions benefits from instrumentation that measures lateral and vertical shifts as well as tunnel subsidence and convergence. Rising to that challenge, the DT ShapeArray automates below-surface deformation monitoring to detect the location of shear planes and other sources of instability in open-pit mining. In underground mining, ShapeArray monitors subsidence effects and anchor bolt drill holes to mitigate the risk of structural failure.
What sets Measurand apart in the geotechnical monitoring industry is the ease of installation using ShapeArray’s patented cyclical installation method, and how the sensors integrate with different collection and transmission strategies from source to endpoint. However, one of the most significant benefits of ShapeArray is the ability to automate real-time data collection and viewing.
Users can collect and share data manually, with semi-automation, or full 24/7 real-time automation.
A field processing unit (FPU) or data logger allows users to plug in a laptop to collect a data set representing a specific period—a snapshot, essentially. This method has low startup costs but requires travel to the site for data collection and viewing. Cost associated with frequent readings can add up rapidly.
Automated collection/manual retrieval:
Automated data collection requires geotechnical sensors to connect to a data acquisition system (DAS), traditionally with cabled connections. The DAS contains the necessary components to collect and store data—a programed data logger, an interface, and a power source.
Depending on the design, DAS can collect data from a variety of different geotechnical sensors used to monitor dams, tunnels, bridges, mines, slopes and other applications.
This method has a higher initial cost but automates the collection and logging of data, saving time by eliminating the need to visit every single sensor. However, technicians still need to visit the location of each DAS hub to physically download and transmit the stored data.
Fully automated wireless data collection and transmission:
Fully automated wireless data collection and retrieval is possible when geotechnical sensors are used with wireless data loggers and communications equipment to transmit data.
This method relies on geotechnical sensors paired with a digital data logger called a node. These node-style data loggers transmit communicate data wirelessly to a fixed DAS hub up to 14 km away for real-time, continuous upload to the internet via cellular or radio transmission. Wireless data logger nodes are powered by long-lasting, standard-sized, lithium batteries.
Fully automated wireless data collection and transmission is ideal for monitoring applications where physical access is a challenge or hazardous to personnel. This method has a higher startup cost but creates an end-to-end system of remote communication—data gets passed from sensors in the field and up to the cloud where it can be viewed via the web, on-demand. A fully automated wireless data collection and transmission strategy ultimately reduces the need to travel to the site to collect data.
Monitoring risk remotely, specifically deformation monitoring and slope stability, is where ShapeArray excels. Frequent manual inclinometer readings are subject to human error, and, in many places, not practical, which can lead to sporadic collection and potentially out-of-date data. Manually collecting data from multiple instruments is time-intensive and cumbersome. But monitoring with ShapeArray is instantaneous and automatic. If configured with a fully-automated DAS, when sensors detect an increased rate of change, an alarm triggers alerting operators of risk. This enables the straightforward integration of real-time slope stability data into the site’s Trigger Action Response Plan (TARP), which ultimately increase safety for onsite crews and minimize downtime costs.
Since 2006, Measurand’s ShapeArray has provided slope stability monitoring in tailings dams and open-pit excavations for mine operators in Alberta, Brazil, Poland (the largest tailings facility in Europe), and subarctic Northwest Territories (Diavik ice diamonds). Mine owners and operators around the globe depend on ShapeArray to deliver monitoring that
ShapeArray real-time data contributes to the overall understanding of the effect of mining operations on the site’s slope stability with the observational method.
The DT ShapeArray by RST Instruments augments Measurand’s innovative geotechnical instrumentation with wireless connective technology, eliminating the need to manage cabled connections between the sensor and the data logger. Wireless connectivity can send information from data acquisition systems to base camps located nearby onsite or to an office workstation a world away. Access to real-time measurements enables decision-makers to protect their workforce and keep operations performing at maximum efficiency.
In applications like tailings waste management, better data leads to better engineering decisions. Geotechnical sensors in tailings dams and structures measure subtle movements deep underground with millimetre-level accuracy. When this data is communicated in real-time, it can save lives and protect the integrity of the structure and surrounding environment.
DT ShapeArray by RST Instruments is a simple-to-implement and scalable platform for low-cost wireless ShapeArray connectivity.
To find out more, contact us today.