Wednesday, October 13, 2010

The Chilean mine rescue continues with 4 men out.

I am sitting watching the rescue of the miners from the copper/gold mine in Chile. Four of the miners have been brought to the surface so far. These were some of the fittest of the men trapped, to make sure that if, in the early stages of the use of the travelling cage, that they could handle any mishaps. And after three rescue personnel rode the cage into the mine, it is now being lowered empty.

The event is being handled with some skill by the Chilean government, they had a camera feed from the bottom of the mine. Thus we saw the rescue cage arrive at the bottom of the mine, and the first of the rescue team get out to help with getting the men out. The trip down takes just over ten minutes, then the harness which the man in the cage wears (which carries an oxygen feed, and also can provide a support since it is hooked to the top of the cage) is removed and passed to the next man to be rescued. He is already wearing a coverall that was made to his measurements, and a jacket (given the move from the heat of the mine to the cold of the desert night at the surface). After donning the harness he is fitted into the cage, the door is closed, and the cage slowly lifted back into the shaft. (It is long enough that it does not come completely out at the bottom and at the top and bottom has spring-loaded wheels that roll on the walls as it moves up and down). It takes fifteen minutes to get to the top, and the rider has a headset so that he can talk to the surface crew while ascending.

So far there has been no glitches in the process, the President of Chile is on hand to greet the miners, and the second one out presented him with a rock from a bagful that he had brought out for the top folk present. And after greeting the dignitaries and a couple, at most, family members the rescued men lie on a gurney and are taken for medical examination. (The fourth man to ride to the surface had only been working in the mine for 5 days and was from Bolivia).

In the chat that the program hosts carry on to fill in the time that the cage is travelling, they talked about the debt that the world owes to miners. These men went on shift on August 5th, working in an old (over a hundred years old) and over-mined deposit and were trapped for 69 days. They are talking about changes that will come about as a result of this, but so often a month after the rescue, it fades into history without much change. Over a hundred years ago in Northern England virtually the entire male population of the mining village of Hartley were killed when the only shaft into the mine was blocked. Yet here this mine had only one effective exit. The second nominal exit, up a ventilation shaft, had no ladder all the way up, and so was not available, though the miners did try it to see if they could get out.

In this case the rescue was helped by the mining and drilling community from around the world. Three different machines were used to drill the holes for the rescue shaft. The speed with which it was done hides the complexity of the job that was achieved. Bear in mind that when the rescue began it was expected to take until Christmas.

There were only two T-130’s in Chile, (the machine that drilled the successful shaft) and there were only certain sized pipe sections available, and so it was a case of working out how to get it done with equipment that had never been used for this before. There were a couple of times when it seemed they might not be able to do it, there was a pause of some four days because of problems with the bit in trying to drill the hard rock, but they worked through it. And they were successful., even though they had to drill around the winding drilled hole that had been drilled first to intersect the rescue area. It required that they bring in the best crew that they could find, and that included flying one driller in from Afghanistan where he had been working drilling water wells. It is likely the most difficult job that they have faced, and this has largely gone unremarked in the media.

Given that the technology was successful there is some talk of developing a permanent set of equipment that can be moved to the site of any future mining disaster, and building on the lessons learned with this event, be better prepared to create access to anyone trapped. This sort of effort will continue to be necessary. Miners work at a considerable distance, normally, from the access shaft through which they enter and leave the mine. In most operations the area around the shaft is left un-mined so that it supports the shaft walls and holds their integrity. This was another safety precaution apparently abandoned in this instance. But it means that miners have to travel some distance to get to the working area, and when disaster strikes they may be a long way from that safe passage out.

Mining will thus remain a dangerous occupation, perhaps even more so in the future. For just as we are now seeing, as the ASPO conference last week noted, the approach of peak oil, so we are also approaching peak minerals. As with oil, the need for future supplies means that smaller and more difficult and dangerous deposits will be worked. In order to save on cost risks will be taken, and men will be trapped and die. It is, sadly, a price that the bulk of society seems quite willing to pay. Fortunately in this case that price does not have to be paid, but unfortunately in too many parts of the world it is still being paid on far too often a basis. And as the need for miners and the minerals and fuels that they produce continues to grow it is hard to see that situation changing much. The 1,500 journalists who are in the desert, without decent accommodation and amenities will soon leave, I would not be surprised, after a while, to hear that miners were back, working in much the same conditions as before. The world need and the money that it will be willing to pay will be incentive enough.

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