Minister says Wednesday rescue likely in Chile
SAN JOSE MINE, Chile – Chile's mining minister said Saturday night that the 33 miners trapped for more than two months will probably be pulled out starting Wednesday.
That's because the rescue team has decided to reinforce less than 315 feet (96 meters) of the rescue shaft in steel pipe.
The rest of the escape shaft is exposed rock, and the rescue team has decided it's strong enough to provide for a smooth ride for the miners' escape capsule.
Mining Minister Laurence Golborne set the date after the shaft was inspected with a video camera Saturday following the completion of the hole earlier in the day — a success that set off celebrations by the miners underground and by their families and rescue workers on the surface.
Golborne and other government officials have insisted the decision on whether to reinforce the whole shaft would be purely technical, based on the evidence and the expertise of a team of eight geologists and mining engineers.
The hole "is in very good condition, and doesn't need to be cased completely," Golborne said.
He said 16 pipes, each six meters (nearly 20 feet) long, would be welded together and inserted into the top of the hole, which curves like a waterfall at first before becoming nearly vertical for most of its depth. The work would begin immediately, he said.
The political consequences of the decision were inescapable. While engineers have said there is only a remote chance of something going wrong if the shaft remains unreinforced, Chile's success story would evaporate if a miner was to get fatally stuck for reasons that might have been avoided.
Encasing just the top of the shaft is a compromise that will protect the miners as their capsule passes through a curved section where the rock is particularly fractured. It's also more technically feasible.
While some miners' families wanted the entire shaft encased, some engineers involved in the rescue said the risk of the capsule getting jammed in the unreinforced hole was less than the risk of the pipes getting jammed and ruining their hard-won exit route.
Many experts doubted whether encasing the entire shaft was even possible.
"Based on my experiences it cannot be done. Nor does it need to be done," Brandon Fisher, president of a U.S. drilling equipment company, told The Associated Press on Saturday.
Fisher, whose Center Rock Inc. made the hammers on the drill that pounded the escape shaft through more than 2,000 feet (622 meters) of solid rock, was closely involved in the drilling effort at the mine.
"The rock is very confident down there," he said.
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Associated Press writers Vivian Sequera at the mine and Frank Bajak in Copiapo, Chile, contributed to this report.
http://news.yahoo.com/s/ap/20101009/ap_on_bi_ge/lt_chile_mine_collapse
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