Australian coal miner, Integra Coal has chosen Mine Site Technologies' (MAT) for site wide digital communications and tracking for both its open pit and underground mines.  A description of the underground part of the installation follows.

Located 8 km north of Singleton in the Hunter Valley, NSW, Brazilian mining giant Vale, operates the Integra Coal complex. These two mines produce a mixture of premium coking, semi-soft and thermal coals for the export market.

The underground mine was looking for a tracking system that would monitor and record the movements and position of equipment, particularly during longwall moves. It can take several weeks to move a longwall and during this period there are a multitude of external factors and unforeseen delays which make it exceptionally difficult to keep track of stored item locations.

The mine also wanted to improve communications by introducing a two-way mobile solution to complement the one-way paging functionality of their existing PED System. This was required to streamline communications with maintenance and repair personnel whilst they are on the move underground. If there was a major equipment malfunction this would take priority and the closest maintenance staff would need to be identified and directed to remedy this immediately.

Additionally, from a safety perspective, Integra management wanted to streamline access control procedures in ventilation zones, by limiting the number of personnel to within the limits governed by available emergency breathing apparatus. Similarly, more accurate monitoring and controlling access of vehicles into ventilation zones was seen as advantageous from an Occupational Health and Safety (OH&S) perspective.

At the heart of the solution are:

20 of MST's ImPact Wireless Network Switches (WNS), each with one or two Wi-Fi radio cards and a four-port fibre switch  17 ImPact Wireless Access Points (WAP), operating from PoE links to their nearest WNS unit. This basic network infrastructure offers Wi-Fi access, active RFID tag reading and VoIP telephony capability.  Additionally power distribution to the communication infrastructure is simplified by using composite power/fibre cable between access points. This custom designed cable contains up to four optic fibres and two power cores, allowing a single power supply to power a number of WNS units.

To allow tracking of the longwall components and development implements, each of these components has an active RFID tag attached, allowing its position to be recorded every time it passes either a WNS or a WAP. This ensures the process of location and identification for each component is greatly simplified.

To identify personnel the mine is upgrading its entire cap lamp fleet and has chosen to invest in 300 of MST's lightweight ICCL's (Integrated Communications Cap Lamps) with integrated RFID tag and PED text message receiver. The ICCL solves both the problem of locating and communicating with underground personnel in one integrated unit, whilst the reduced weight of the Lithium Ion battery offers OH&S improvements by reducing each miner's belt weight. People can be located quickly and easily with the tracking system and operational dispatch messages can be sent directly to the required person via the PED one way pager, ensuring efficient communication.This tracking and communication cycle will be enhanced further once MST's VoIP telephone handset is approved for use in coal mines, by allowing more complex two-way communication to occur when required. The Wi-Fi network has been set up to provide seamless VoIP coverage along the travel road from the surface to the longwall, as the ImPact WNS units provide continuous Wi-Fi coverage along the underground roadways.

Apart from the introduction of the VoIP telephones following their approval, the installation will be extended into hazardous zones areas within 12 months after the Intrinsically Safe version of the Impact WNS units become available.

John Chadwick is editor/proprietor of International Mining magazine -