Another cave-in is possible, though unlikely. Poor sanitation may be a health hazard. And the food reaching them is likely to leave them malnourished, experts say.

The miners' fate, however, likely hinges not on physical conditions but on their mental health and their ability to keep each other hopeful, psychologists say.

"If the miners who are trapped can bond and work together to tick off the days they are separated from their families and friends, it would help them survive the ordeal," said John Cacioppo, a psychologist who specializes in social isolation in humans and animals at the University of Chicago.

(Read "Mining's Hard Rock Legacy.")

The ordeal began on August 5. The roof of the San Jose gold and copper mine