Due to their nature and the way they are constructed and expanded, surface/open pit mines generally contain one or more bodies of water. Mostly this takes the form of water that accumulates at or near the bottom of the mine. Additionally, as surface mines are built or expanded, they may encounter existing, natural bodies of water.

An important part of ensuring that surface mines operate as safely and as productively as possible is continuous and ongoing monitoring of the water bodies within and adjacent to the mine, especially in terms of their water level and pressure. The main instrument used by mine engineers for this purpose is the piezometer, often the vibrating-wire type.

Piezometers determine the status of bodies of water by measuring the height to which a column of water rises against gravity. These instruments collect vital data about the status of accumulated water in the mine, and especially any potential changes that may increase operating risks.

Data collected by an array of piezometers deployed throughout a mine property can guide engineers and help them spot potential risks developing, and then deal with them efficiently while they are still easily manageable.

However, to fully utilize the data generated by piezometers, engineers must have easy access to the information. It is in this context that electronic monitoring systems prove invaluable. Piezometers can be connected to wireless nodes, which are then integrated into a comprehensive piezometer monitoring system — for example, a mine-wide wireless mesh sensor network that is driven by a top-class monitoring system like the Loadsensing LS-G6 wireless monitoring and data acquisition system. This allows engineers to access data that is easy to understand and use, directly from their office PC or laptop.

A piezometer monitoring system built in this way consists of four main elements:

1.Vibrating-wire piezometers (or other hydrological measuring instruments)

2.Wireless nodes

3.One or more Ethernet gateways

4.A central monitoring and data-processing system

Benefits of such a system include:

• Wireless functionality (nodes are powered by batteries that will last from 3-10 years, depending on usage)
• Plug-and-play installation
• Simplicity and user-friendliness
• No interruption of production to take readings

Connecting multiple piezometers to a wireless mesh network that links via the monitoring system to engineers’ computers removes the need for time-consuming and inefficient manual collection of data and piezometer monitoring.

This allows the engineers to spend most of their time using the data to make the mine safer and more efficient, rather than having to walk around reading data from dozens (or possibly hundreds) of hydrology piezometers spread throughout the mine.

The Loadsensing LS-G6 long-range wireless data acquisition and monitoring system (built by Worldsensing) is a logical choice when it comes to a wireless piezometer monitoring solution suitable for all surface/open-pit mines.

This system offers a number of benefits; for example:

• It can read all commonly used types of piezometer (as well as other types of hydrological and geotechnical sensors).
• Safety thresholds can be determined and programmed into the system by engineers. The system will then monitor these thresholds and check them at user-defined intervals, from once every 24 hours down to every 30 seconds, and provide a warning alarm if a safety threshold is breached.
• Total wireless functionality. Data is moved quickly and efficiently from sensors via a Loadsensing gateway into a cloud-based solution, from where it can be easily accessed by engineers via a PC or other device, anywhere in the mine, or even offsite.