Long-Term Pore Pressure Monitoring at a Major Mine in Southern Africa

Context

Over the past decade, GE Monitoring Systems (GEMS) has supported a large, established mining operation in Southern Africa through the gradual development of a comprehensive pore pressure monitoring network.

The installation program began with a small number of vibrating wire piezometers and expanded steadily as operational requirements grew and new monitoring zones were identified. Today, the network includes more than 200 instruments connected to over 100 data loggers across the site.

The instruments are installed across a variety of locations — from shallow 30–50 m boreholes to deeper installations exceeding 400 m — including pit walls, pumping stations, stormwater areas, and surrounding farmland used for environmental compliance monitoring. The system plays a critical role in managing seepage, maintaining drawdown balance, and preventing perched water tables that could compromise pit wall stability or impact downstream water users.

Solution

The network is based primarily on vibrating wire piezometers, complemented by a small number of crackmeters for localised surface movement assessment. Each data logger connects to a wireless telemetry network, which aggregates data via multiple gateways into a unified cloud-based system.

Using the Cloud platform, all incoming readings are validated, filtered for duplicates, and transmitted automatically via API to the mine’s central IoT platform, where they integrate directly into the operational monitoring interface. This configuration allows site teams and management to view live groundwater and pore pressure data alongside other mine operational systems in real time.

The system has been refined over time through multiple technology generations to achieve consistent reliability in harsh semi-arid conditions. Despite high ambient temperatures, heavy rainfall events, and frequent lightning, the monitoring network has maintained excellent operational continuity. Downtime has been limited to occasional lightning strikes or battery depletion incidents, both addressed through training and equipment updates.

Benefits

The long-term implementation has provided continuous pore pressure data across key operational zones, enabling early detection of seepage trends and improved management of pumping activities. The integration of real-time data with the mine’s monitoring systems supports proactive water management and environmental compliance by ensuring that surrounding farmlands are not affected by over-abstraction or shifting water tables.

The system’s reliability and scalability have made it a benchmark for groundwater instrumentation in active mining environments, demonstrating how progressive upgrades over time can evolve into a robust, interconnected monitoring solution without requiring full system replacement.

Outcomes

The project demonstrated:

• Scalability – Expansion from a small initial network to more than 200 instruments over ten years.
• Integration – Seamless API-based data flow into the mine’s IoT system.
• Resilience – Proven performance under extreme heat, rainfall, and lightning exposure.
• Environmental assurance – Continuous monitoring of water in and around the pit and surrounding groundwater conditions.
• Operational continuity – Minimal downtime across a large, distributed monitoring network.
  

This long-term installation highlights GEMS’ capability to design, adapt, and maintain reliable monitoring systems across evolving mine conditions, supporting both operational efficiency and environmental responsibility.