Since a note in red marker came up from the depths of the Atacama desert, alerting the world that the Chilean miners buried for 17 days and feared dead were trapped but alive, the globe has kicked into gear to secure their rescue. Space agency specialists, schooled in enduring isolation, are on the ground, as are the world's best mining experts from the United States to Australia.
If ever there was a moment of optimism in tragedy, it is now. But the rescue effort that is under way, a strategy that necessitates that the miners remain a half mile underground for up to four months, will be one of the most complex challenges of its kind, with the mental health of the miners a central concern and an engineering task promising no clear outcome.
"Because of the rock, it will take a fair amount of time. They will have to put in the rescue shaft very carefully to make sure, while drilling, they do not change the nature of the conditions," says Michael Nelson, chairman of the mining and engineering department at the University of Utah. "People think we just have to drill a hole. They think of taking a drill in their garage and drilling through a piece of wood.... In any human effort where we are doing things in earth, we are dealing with something never completely known."
The rock in which they were mining has a tendency to weaken in areas, experts say. The roof of the gold and copper mine collapsed Aug. 5, trapping the miners three miles from the entrance and 2,300 feet down. The miners took refuge in a nearby shelter containing food, water, and oxygen.
On Aug. 31, rescue efforts began as a 31-ton Raise Borer Strata 950 started carving out some 20 meters (about 66 feet) of rock per day. At that rate, it could take until after Christmas to drill a two-foot-diameter hole some 2,300 feet down. Cages would then lift the miners out over a three-to-four-day period, says Chilean Mining Minister Laurence Golborne.
Because the target shaft is being designed by engineers familiar with the drills and the geology in this part of the desert, Andrew Wala of the University of Kentucky says he is confident the men can be secured safely. "They are going to drill a small diameter to get these people. I doubt there will be the possibility of the shaft to collapse," says the professor of mining and engineering.
Yet the number of backup options – 10 in all, according to Mr. Golborne – points to the many unknowns in this rescue operation. If the Strata 950 should fail, then a backup Strata 950 drill is waiting. If the backup drill also fails, then a T-130 drill could be used to widen an already existing hole that reached the miners shortly after they were found. That original hole was drilled with help from Australian drilling consultant Kelvin Brown, who flew to Chile to assist in the efforts. Some plans halve the estimated rescue time to two months.
The rescue is precarious, but not because of the depth or the type of rock, says Professor Nelson of the University of Utah. Shafts as deep as 8,000 feet have been drilled in all types of rock conditions in search of gold, diamond, or copper. "The operation itself is something that has been done a lot before, but nobody has ever done it with the added pressure to rescue a group of 33 people," he says. "The challenge is to try and proceed in a rational manner, following good engineering practice, and do so as quickly as possible for the good of the humans involved."
While the men have received hot meals, music, and other supplies to keep their spirits up, their psychological conditions are fragile. They are living in a 540-square-foot space with a temperature of about 86 degrees F., meaning each breath utilizes more oxygen, says Professor Wala of the University of Kentucky. "It is the temperature and oxygen levels they will have to watch," he says.
On Sept. 1, a team of NASA specialists, including two physicians, a psychologist, and an engineer, arrived at the mine to analyze the miners' nutritional states. Given the team's experience in training for isolation, NASA has also launched a full-scale psychological program.
"The environment may well be different [from space], but the human physiological and behavior responses to emergencies are quite similar," said James Michael Duncan, NASA's deputy chief medical officer. "We think some of the things we've learned, either in research or in operations, can be applicable to the miners that are trapped underground."
Positive thinking will be integral, officials say. The Chilean government is reportedly monitoring family letters to prevent downbeat news from dampening spirits. And the psychological team in Chile has ordered the men to help in their rescue by storing several thousand tons of debris as it tumbles down a shaft near the shelter. Having a role in their own liberation could prove beneficial.
Prisoners of war or those in solitary confinement have shown varying degrees of success in isolation, says Albert Boquet, the chair of human factors and systems at the Embry-Riddle Aeronautical University in Florida.
Camaraderie and teamwork will be key for the miners, says Professor Boquet. "They are going to wax and wane in terms of their mood somewhat," he says. "But they seem really positive; that is a No. 1 for being able to wait this out."