Contents of Engineering & Mining Journal - FEB 2012

Engineering and Mining Journal - Whether the market is copper, gold, nickel, iron ore, lead/zinc, PGM, diamonds or other commodities, E&MJ takes the lead in projecting trends, following development and reporting on the most efficient operating pr

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SAFETY Keeping Mineworkers Safe By Simon Walker, European Editor
It is a salutary thought that mining often only comes into the public eye for one of two reasons: either a major environmental incident, or an accident involving the loss of life. Most of the time, fortunately for everyone involved, mines keep running safely, with experienced operators able to manage the risks involved so that the inci- dence of injury and death is minimized.
In 2011, for instance, there were five fatalities in underground U.S. metal mines, according to data published by the Mine Safety and Health Administration (MSHA), each of which was an individual event—in other words, only one person was involved, and they were isolated inci- dents. Major mine rescues, as occurred in Chile the previous year, are truly few and
far between and, it has to be remem- bered, instances where large groups of miners in underground metal mines are affected by some incident are so rare as to be positively remarkable.
Outside and inside: MineARC's moveable hard rock refuge chambers can provide a safe haven for up to 26 people in the event of an emergency.
42 E&MJ; • FEBRUARY 2012
Indeed, when compared to the coal- mining sector, metal mining is intrinsi- cally less prone to fatal accidents, although the potential for serious injury remains. Unlike coal, the risk of explo- sion underground is remote although, as has been shown in the past, nature can throw up some unexpected surprises. The realization (many years ago) that methane was present in deep potash workings in Britain brought about a swift re-appraisal of operating practices there. While water is another major hazard, yet again major incidents have been rare. The Mufulira inflow in 1970, in which an estimated 1 million metric tons of tail- ings slimes flowed into the mine, was a one-off in terms of the circumstances and the loss of life. In South Africa, West Driefontein was saved after the water inrush there in 1968, and remains one of the country's leading gold producers. Canada's potash mines have had their own water problems in the past, although potash is one commodity that is amen- able to solution recovery, as well as con- ventional mining. However, the most dangerous situa- tion underground, without question, is fire, and although the potential causes of fires may have changed as new mining technologies have been introduced, the critical scenario remains. Probably the last time a serious timber-fueled fire occurred in the U.S. was the Homestake incident in February 2001, when fire started in a worked-out, timber-supported area of the mine. With few mines now relying on heavy timbering, today it is much more likely that fire will be caused by either electrical or diesel-powered equipment—indeed, MSHA and NIOSH statistics prove this to be the case. Whatever the cause, fire in a confined space is a terrifying experience, not only from the threat of the fire itself, but also
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and survivability underground A look at some of today'
s technology that is designed to enhanc
e safety