Combined Innovation on TSF
In a demonstration of successful group collaboration and technical proficiency, Geomech Africa and Terra Monitoring collaborated on a turnkey solution project for a major tailings storage facility (TSF) in South Africa.
Geomech Africa expertly prepared the groundwork, undertaking their comprehensive geotechnical investigation across 22 locations using rotary core and sonic drilling methods. Their scope included drilling the 19 specific boreholes required for Terra Monitoring's VWP installation, as well as conducting specialised in-situ testing such as Dames & Moore sampling and Dilatometer (DMT) testing for their broader investigation aims.
Managing challenges such as hard near-surface formations (requiring strategic borehole advancement) and weather risks inherent to TSF sites (like proactively managing rigs during thunderstorms), Geomech Africa ensured the integrity of the boreholes designated for instrumentation. They took care to prevent contamination and installed permanent 70mm slotted PVC casings, wrapping and securing geofabric to enclose the slotted section, preparing the way for the instrumentation installation. The geofabric specific micron size allows water to enter the casing, while preventing sand and other materials from entering the PVC casing.
Terra Monitoring's core objective was to install 19 Vibrating Wire Piezometers (VWPs) and four 5-channel data acquisition nodes, enabling the collection of vital ground and water pressure data at pre-designated locations for ongoing safety and stability assessment.
Mobilising to the site on August 14th, 2024, the Terra Monitoring technician then began the meticulous installation process:
Geomech Africa expertly prepared the groundwork, undertaking their comprehensive geotechnical investigation across 22 locations using rotary core and sonic drilling methods. Their scope included drilling the 19 specific boreholes required for Terra Monitoring's VWP installation, as well as conducting specialised in-situ testing such as Dames & Moore sampling and Dilatometer (DMT) testing for their broader investigation aims.
Managing challenges such as hard near-surface formations (requiring strategic borehole advancement) and weather risks inherent to TSF sites (like proactively managing rigs during thunderstorms), Geomech Africa ensured the integrity of the boreholes designated for instrumentation. They took care to prevent contamination and installed permanent 70mm slotted PVC casings, wrapping and securing geofabric to enclose the slotted section, preparing the way for the instrumentation installation. The geofabric specific micron size allows water to enter the casing, while preventing sand and other materials from entering the PVC casing.
Terra Monitoring's core objective was to install 19 Vibrating Wire Piezometers (VWPs) and four 5-channel data acquisition nodes, enabling the collection of vital ground and water pressure data at pre-designated locations for ongoing safety and stability assessment.
Mobilising to the site on August 14th, 2024, the Terra Monitoring technician then began the meticulous installation process:
- Preparation: VWPs were saturated in clean water and zero readings taken to ensure accurate baseline data.
- Verification & Adaptability: Initial depth checks using an electronic dip meter revealed siltation had affected some borehole depths. The team adeptly responded by using a water pump to clear the holes, ensuring instruments could be installed at the correct elevations. Water was injected into the PVC under pressure, effectively bailing them clean from any silt.
- Precise Installation: Following best practices, all installation depths for seals and filters were constantly monitored using an electronic dip meter. Bentonite seals were allowed adequate time to settle.
- Infrastructure & Connectivity: Cables were protected within conduit sleeves laid in trenches (specifically across haul roads), connecting the VWPs to the strategically placed nodes mounted on concreted steel poles. Regular testing during installation confirmed VWP functionality. The system was properly grounded using spikes and cables connected to all nodes, and the Geosense nodes and gateway were configured using manufacturer specifications, zero readings, and calibration certificates.
The Challenge & Collaboration:
Monitoring the geotechnical conditions of tailings facilities is crucial for operational safety and environmental protection. This project required the precise installation of instrumentation within boreholes prepared by Geomech Africa, whose team was concurrently managing a larger investigation scope. Success depended on seamless coordination between Geomech Africa's site investigation team and Terra Monitoring's instrumentation specialists, both part of the GeoGroup, and strict adherence to the project specifications for the in-situ testing and monitoring system installation.
Execution & Overcoming Obstacles:
This project exemplifies the strength of collaboration within the GeoGroup, combining Geomech Africa's comprehensive site investigation and drilling expertise with Terra Monitoring's specialised instrumentation capabilities. The successful, safe, and timely delivery of this essential monitoring system by Terra Monitoring, supported by the groundwork laid by Geomech Africa, highlights the group's ability to provide integrated geotechnical solutions that meet critical client needs on complex sites.
Monitoring the geotechnical conditions of tailings facilities is crucial for operational safety and environmental protection. This project required the precise installation of instrumentation within boreholes prepared by Geomech Africa, whose team was concurrently managing a larger investigation scope. Success depended on seamless coordination between Geomech Africa's site investigation team and Terra Monitoring's instrumentation specialists, both part of the GeoGroup, and strict adherence to the project specifications for the in-situ testing and monitoring system installation.
Execution & Overcoming Obstacles:
This project exemplifies the strength of collaboration within the GeoGroup, combining Geomech Africa's comprehensive site investigation and drilling expertise with Terra Monitoring's specialised instrumentation capabilities. The successful, safe, and timely delivery of this essential monitoring system by Terra Monitoring, supported by the groundwork laid by Geomech Africa, highlights the group's ability to provide integrated geotechnical solutions that meet critical client needs on complex sites.
Plot 28 Central Road
Sunrella, Lanseria
Gauteng
South Africa
Tel. +27 (0)861 436 632
Email. info@geogroup.co.za