The accident that claimed the lives of four mine workers on November 24 at the Northparkes copper and gold mine near Parkes, in central west New South Wales, again focuses attention on the issue of safety standards in the mining industry.
The four men, Ross Bodkin 41, Michael House 33, Stuart Osmond 47 and Colin Lloyd-Jones 41, were killed instantly when millions of tonnes of ore and earth collapsed suddenly causing a catastrophic air blast through an access tunnel in which they were working 140 metres below ground.
The collapse extended hundreds of metres right up to ground level. The resulting wind blast was so powerful that it ripped apart the two-tonne Toyota Land Cruiser carrying two of the men and spread shattered metal and wreckage over a kilometre along the mine shaft. The police believe that the injuries will be so severe that they will have to rely on dental charts and other personal data to confirm the identity of the dead. The initial identification was made on the basis of the four work tags that remained on the board after other workers were brought to the surface.
One of the mine's engineers said: "Normally not much ore falls down. This time it appears a huge amount fell. There would have been a massive blast of air and even if the miners had been some distance away, there would have been nowhere for the air to escape. It was like being trapped in a piston.”
The incident could easily have resulted in a greater loss of life. Another 57 men were carrying out maintenance work on mining and crushing equipment in the control room some 300 metres below the access shaft. The blast caused the ground to shake around them. They were forced to remain underground for over three hours while rescue teams sought to determine whether it was safe for them to exit.
Malcolm Bloomfield, the managing director of North Limited, the mine's owner, stated that the deaths had been caused by an “irregularity” in the mining method currently in use at the mine. Northparkes is the only underground mine in Australia using a method of ore extraction known as block caving.
The technique consists of creating a void in the ground under a core of ore. Miners precipitate a movement in the ore body through gypsum cracks producing what is known as a "controlled collapse". The conglomerate above then falls into the void where the ore is recovered through points at the base that are serviced by protected access tunnels.
When a “controlled collapse" is in progress there is normally a crew of about six men and the process is done largely by remote control. The team is located in the protected control room.
A company spokesman confirmed that the accident took place during a maintenance shutdown and that there was no mining taking place at the time. He said that the company had no explanation for the unexpected collapse, saying, "on this occasion the body of ore decided to move itself”. He claimed that there had been no prior indications. The matter is now the subject of several investigations.
The inability of the company to explain why an unscheduled collapse occurred and why it had taken them by surprise puts a question mark over the whole procedure. It also challenges the management's claims that block caving is a safer method of mining than most because only a small number of people are underground when the mining is in progress.
The central attraction of block mining is not its safety features. Northparkes management admits that it adopted the method because it is a cheap means of extracting large quantities of the low-grade ore. When the mine first opened the management claimed that the operation had the potential for becoming the “lowest cost underground hard rock operation” in the country.
This prediction has been borne out. In the first six months of operations this year, the mine has already exceeded its projected full year's profit. While the mine only employs 200 men, its ore mining and processing capacity stands at five million tonnes per annum.
Any mining method involving “controlled” collapses contains inherent dangers and as the incident at Northparkes demonstrates it can produce unpredictable results.
Although not the same as block caving, controlled collapses in the coal mining industry have already resulted in incidents that could have ended in the loss of life. One such method, in which a mechanical miner moves forward allowing the roof to collapse behind it, is currently in use at the underground Moonee Colliery at Catherine Hill Bay, just south of Newcastle.
In early 1998, 19 miners were injured in an air blast at Moonee when the roof was allowed to collapse. In April the following year, another miner Steven Chandler suffered serious injuries when a collapsing roof caused a massive blast of air to surge through the shaft where he was working. The mine's manager Ross Campbell defended the company's decision to continue with the method because “it made the operation viable,” that is profitable.
Despite numerous official inquiries into the safety conditions in NSW mines and a mountain of recommendations, the death toll continues to mount. Last week's tragedy at Northparkes brings the total number of fatalities in NSW mines since March 1995 to 28—an average of seven deaths every year. Northparkes is the most serious accident since four miners were killed in the Gretley Colliery, near Newcastle in November 1996.
Only last year the Labor government claimed to have implemented most of the 44 recommendations handed down from the inquiry into mine safety initiated in 1996 to quell growing anger in mining communities. The recently completed judicial inquiry into the Gretley deaths produced another 43 recommendations and last month the government announced it was now planning prosecutions.
But the official inquiries will not bring about a progressive change in the grave situation facing miners because they are designed to mystify the underlying causes that have produced it. Over the past years, driven by increasingly ruthless international competition, the mining companies have demanded the removal of any impediment to increased productivity. In the resulting “hot house” atmosphere in the mines, greater production has increasingly taken precedence over safety.
Despite the evidence to the contrary, the mining unions have hailed the outcome of each inquiry as a step towards greater safety in the mines. The unions are deeply implicated as they have collaborated for over a decade in the drive for “international competitiveness”. The destruction of thousands of jobs, the reduction of manning levels, and longer working hours and shifts have all contributed to the undermining of safety standards.