SAN JOSE MINE, Chile – After more than two months trapped deep in a Chilean mine, 33 miners are enjoying Sunday tantalizingly close to rescue.
Drillers have completed an escape shaft, and Chile's mining minister says a video inspection shows the hole's walls are firm enough to allow the men to be hoisted out as early as Wednesday.
Officials said late Saturday that workers first must reinforce the top few hundred feet (almost 100 meters) of the tunnel and had begun welding steel pipes for that purpose.
The completion of the 28-inch(71-centimeter)-diameter escape shaft Saturday morning caused bedlam in the tent city known as "Camp Hope," where the miners' relatives had held vigil for an agonizing 66 days since a cave-in sealed off the gold and copper mine Aug. 5.
Miners videotaped the piston-powered hammer drill's breakthrough at 2,041 feet (622 meters) underground and could be seen cheering and embracing, the drillers said.
On the surface, the rescuers chanted, danced and sprayed champagne so excitedly that some of their hardhats tumbled off.
Later, a video inspection of the shaft gave rescuers enough confidence in the tunnel's stability that they decided they will encase only its first 315 feet (96 meters).
The plan is to insert 16 sections of half-inch(1.27 centimeter)-thick steel pipe into the top of the hole, which curves like a waterfall at first before becoming nearly vertical for most of its descent into a chamber deep in the mine. That work would begin immediately, Mining Minister Laurence Golborne said.
AP – A relative of a trapped miner gestures after the announcement that a drill reached the trapped miners
Then an escape capsule built by Chilean naval engineers, its spring-loaded wheels pressing against the hole's walls, can be lowered into it via a winch and the trapped miners brought up one by one.
"All rescues have their risks," Golborne said. "You can never say that an accident couldn't happen."
Golborne and other government officials had insisted that determining whether to encase the whole shaft, only part of it or none of it would be a technical decision, based on the evidence and the expertise of a team of eight geologists and mining engineers.
Encasing the full shaft would have added another week or so before the rescue could begin — if it could actually be done.
While the possibility of an accident can never be ruled out, the hole "is in very good condition, and doesn't need to be cased completely," Golborne said.
The political consequences were inescapable. Chile's success story would evaporate if a miner should get stuck on the way up for reasons that might have been avoided.
Some miners' families wanted the entire shaft lined with pipe, but some engineers involved 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 the U.S. company that built the drill that broke through, told The Associated Press on Saturday.
"The rock is very confident down there," he added.
Health Minister Jaime Manalich said the miners' anxiety is growing about starting their rescue, an operation that should take about a day and a half to complete as they are pulled out one by one in a specially built capsule.
Manalich also confirmed that a list has been drawn up suggesting the order in which the 33 miners should be rescued. The final order will be determined by a Navy special forces paramedic who will be lowered into the mine to prepare the men for their journey.
The completion of the escape shaft thrilled Chileans, who have come to see the rescue drama as a test of the nation's character and pride.
Coppied by http://news.yahoo.com/s/ap/20101010/ap_on_bi_ge/lt_chile_mine_collapse
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