Why will Chilean miners' rescue take so long?

The Chilean miners have been trapped 2,300 feet underground for nearly four weeks. The specific cause of the collapse isn"t yet clear. According to estimates, the 33 miners won"t be rescued until sometime near Christmas, four months from now. The drilling is now under way, but many Web searchers are wondering why the process takes so long. Here"s the layman"s explanation:

There are two main problems that make an underground rescue like this such a long and tedious endeavor. The first is that the miners are buried under solid rock. This isn"t dirt, so it"s not as simple as getting some construction equipment and digging. The rock itself can"t be moved, so it must be drilled through. Even for experts with top of the line resources, this takes a long time.

The second problem comes from the miners" end. As the rescuers drill down, rock will inevitably fall on the trapped men. An AP article on USA Today explains that miners will have to "aid their own escape" by "clearing thousands of tons of rock that will fall as the rescue hole is drilled." If the miners don"t keep the bottom clear of debris, the rescue hole could fill up. That would delay the rescue even further, an outcome nobody wants.

Experts seem to think there is little risk that the rescue attempt could put the miners in greater danger. What"s troubling is whether the miners can stay healthy, both mentally and physically, given their incredible circumstances. Already, just several weeks in, the miners are showing some health issues. According to experts who have watched videos of the miners below ground, some are showing signs of skin problems, and others are suffering from depression.

To help combat the mental fatigue, the miners have assigned themselves jobs. For example, one miner named Yonnie Barrios has been assigned head of medicine. Others workers collect safety supplies from the surface, while another group works on fortification. The men are sending up urine samples so doctors can do their best to monitor their health.

There is also considerable Web interest in "Plan B," an accelerated plan for freeing the miners that involves widening one of the three narrow existing holes being used to reach the miners. Plan B would take about two months, and has the backing of many. But, according to CNN, the country"s mining minister quickly cautioned against setting what he called "unreasonable expectations."

AFP has some specifics on the drill being used to rescue the miners. "The giant Strata 950 machine will bore a 33-centimeter (13-inch) pilot hole that must then be widened by a special drill bit." Once that hole has been made, the special drill bit will widen the hole to somewhere between 60 and 70 centimeters (or about two feet).

The hope is that that hole will be wide enough for the rescuers to lower a kind of escape pod. One by one, the miners will be lifted up to the surface.

(Agencies)