Chile's operation to winch 33 trapped miners to safety will begin at midnight local time tomorrow (3am GMT Wednesday), officials said, after engineers tested a specially designed escape capsule.
Mining minister Laurence Golborne said miners would start being individually evacuated 68 days after the collapse of part of the gold and copper mine in the Atacama desert.
Earlier, rescuers completed lining a segment of a shaft through which the miners will be brought to safety. Engineers worked through the night to lay 96 metres of sheet metal at the top of the 622-metre tunnel, finishing at 3am local time, prompting cheers and shouts of "Viva Chile!". Test-runs of the rescue capsule, dubbed "the phoenix", were undertaken this morning, Golborne said.
President Sebastián Piñera is due to visit the site tomorrow, possibly accompanied by his Bolivian counterpart, Evo Morales, who has requested attendance because one of the trapped men is Bolivian.
Rescuers said they would resume drilling a separate shaft as a back-up plan in case of problems with the first one. On its journey to the surface, the capsule will have to twist up to a dozen times through curves of 28-inch (78cm) diameter.
Video inspections showed the shaft's lower walls to be firm, smooth rock, eliminating the need to line them, which would have taken days and risked blockages.
The health minister, Jaime Manalich, said that at least two rescuers, including a paramedic, would be winched down to prepare the men for a fraught, claustrophobic journey that could take between 10 and 40 minutes.
Authorities wanted the most stable miners to go up first, he said. "They have to be psychologically mature, have a great deal of mining experience and be able to handle a quick training on how to use the harness and oxygen mask in the phoenix capsule."
A few had volunteered to go up first and several expressed a desire to go last in "a completely admirable show of solidarity", said the minister. One motive to be last, however, is a guaranteed place in the Guinness World Records for the longest time a miner has ever been trapped underground. Given the complexities of the current situation, it is a record that many expect to be insurmountable.
The men will be given green waterproof suits designed to let their skin breathe as they ascend, and at the top they will receive a pair of Oakley Radar sunglasses to shield them from sunlight before beginning a 48-hour evaluation of their physical and mental health.
