Chilean rescue workers are drilling into the last 100 metres of rock to reach miners trapped a half-mile underground and may begin pulling them out by the end of the weekend.
Mining Minister Laurence Golborne was set to fly to the mine site in northern Chile last night as the operation, the longest on record, nears its final stages.
The 33 men, stuck for more than two months in a 50-square-metre room, haven't been told how close they are to being freed to avoid potential disappointment if the operation is delayed.
"The deeper it gets, the more complicated things become," said Eugenio Eguiguren, international vice president of Geotec Boyles Bros., which is digging the hole. "Everything is going well. I think they'll be getting out this Sunday or Monday."
One of three rescue shafts reached a depth of 520 meters yesterday, about 100 meters short of where the miners took shelter on August 5 when the mine collapsed, Mr Eguiguren said in a telephone interview from Santiago. Once the drilling rig reaches the men, which may happen as soon as tomorrow, rescuers will send down a video camera to determine if the shaft is stable enough to pull out the workers without first casing the walls, he said.
Installing a steel casing would take three or four days. If it's not needed, the miners could be brought out beginning October 10.
The miners were trapped after an access tunnel caved in at Cia. Minera San Esteban Primera SA's San Jose copper and gold mine in the Atacama region. Chile's state mining company and BHP Billiton Ltd. assisted in the effort to drill the rescue shafts.
The miners' only contact with the outside world has been through small drill holes into which people on the surface pass down food, water, medicine and games such as dominoes. Miners were told yesterday that drilling had advanced; they weren't informed of the extent of the success, Andre Sougarret, the chief engineer in charge of rescue operations, told reporters yesterday at the mine.
Once officials reach the trapped miners and give the go- ahead to begin rescue operations, a tube 24 inches wide will be lowered into the hole, which measures 26 inches at its narrowest point, La Tercera newspaper reported yesterday. At 120 meters, rescuers will have to navigate a sharp turn before the hole drops straight down to the miners, the newspaper reported.
The technique of lifting workers from a man-sized hole first proved successful in 1963 when David Fellin and Henry Throne were pulled out of the Sheppton coal mine in Pennsylvania after being trapped for 14 days. A similar rescue effort in 2007 at a coal mine in Crandall Canyon, Utah, ended in failure after six miners and three rescuers were killed.
Agencies