Old mines need to be properly understood - because as their existing mineral ore bodies are mined out, dangers to mine personnel increase significantly.
“As mines get ‘mined out’, there are more hazards to look out for: gas, water, old mine workings and so on,” says Hennie Grobler, the University of Johannesburg’s (UJ) Head of Department for minerals surveying.
To better manage these and other challenges such as mineral rights ownership within the surveying discipline, the South African Government in May this year instituted the Geomatics Council. Grobler has been appointed an alternate to Prof Fred Cawood from Wits University at the Council.
“It is becoming more and more of a problem, as large mining companies mine next to each other on adjacent properties. If these companies don’t talk to each other, they may intrude into each other’s old workings and this is when accidents happen easily,” continues Grobler.
The Mine Health and Safety Act prescribes the boundary limits and accuracy requirements that mine surveyors must ensure mines comply with.
If one mine should inadvertently mine through its boundary into another mining property, there are two issues. Firstly - mining minerals that don’t belong to them. Secondly, if mining activities lead to a working area breaking into an abandoned mining area, which they won’t know about, accidents are likely.
In an incident in Australia a few years ago, 15 people died when one mine ‘holed’ into the old workings of another abandoned mine, he says.
“Usually methane gas starts accumulating in old workings, which causes devastating explosions. Approximately two months ago such an explosion happened in an abandoned mine shaft in the Welkom area.
“Water and mud also accumulates in these workings under tremendous pressure. If you have a flood underground, there is nowhere to run or to swim. People caught in such a flood have no chance at all. That is why the government requires by law that a mine surveyor must identify on the prescribed plans any such potential hazards,” says Grobler.
It is a challenge to work out exactly what is located where, in relation to the ore body, when surrounded by solid rock. Mining surveyors study the data from the geology for an area, combine that information with plans of mine workings, to work out what can be expected ahead of the ‘face’ or area to be actively mined next.
To avoid accidents, keep within the boundaries of a mining property and also reach the ore safely, the mine surveying information for an operation has to be of a high standard.
To this end, the Geomatics Act provides for the establishment of the SA Geomatics council as a Juristic person to provide categories of registration for persons working in the Geomatics field including land surveyors, mine surveyors, engineering surveyors, hydrographers and geographic information science practitioners.
The council will identify areas of work to be performed by the various categories of registered persons and will provide measures to protect the public from unethical Geomatics practices by maintaining high standards of professional conduct and integrity.
“It is important to have representation at the Geomatics council and provide perspective in relation to the duties and requirements that mine surveyors must comply with in terms of the Mine Health and Safety Act,” says Grobler.
Grobler is a registered Professional Mine Surveyor, with a Government Certificate of Competency for Mine Surveyors since 1994. He worked in the mining industry as a mine surveyor for 18 years before joining UJ in 2007. Grobler is also a member of the Royal Institute of Chartered Surveyors.