On 24th July 2002, two shifts of miners - 18 men in all - entered the Black Wolf Coal Company's Quecreek No 1 Mine, a few miles north-west of the town of Somerset, Pennsylvania. Some seven hours later, nine men were trapped by rapidly rising water in a cavern more than 200 feet below ground, and the nine others, drenched and exhausted, had managed to struggle out to safety.