Chile Plans to Drill a Second Tunnel to Speed Rescue of 33 Trapped Miners

Aug 29 (Bloomberg)--

Chile plans to drill a second tunnel in a bid to free 33 workers trapped in a collapsed copper mine sooner than the 120 days originally forecast.

Engineers plan to widen an existing four-inch hole, allowing rescue workers to reach the miners 700 meters (2,300 feet) below the surface in two months instead of four. Walter Herrera, whose company is installing the drilling machine to bore the tunnel, said work on the second shaft may begin within five days.

"Under ideal conditions, this could take around two months,” Hererra said in televised remarks to reporters at the mine.

Herrera said the bore would be about 28 inches wide and 600 meters down the San Jose mine in which the miners are trapped.

Workers are also installing a 40-ton drilling machine called Strata 950 that will begin work soon on another tunnel to reach the miners. The government estimates that tunnel will take at least three months to complete, making it the longest-ever mine rescue, according to the Uniontown, Pennsylvania-based U.S. Mine Rescue Association.

"This has never been done before anywhere in the world,” Enes Zepeda, director of the supervisors’ union at Codelco, Chile’s state-owned copper company, which is aiding the rescue, said in a telephone interview.

Possible Collapse

There is a possibility of further collapses in the mine because of its age, Henry Laas, managing director of Murray & Roberts Holdings Ltd., the parent company of Terra Service, said in an e-mailed statement.

"Rescuing the miners will be a challenging process,” Laas said. “We are optimistic that the rescue operation will be completed safely in the next 120 days.”

Drillers must bore through the “unstable geology” of Chile’s Atacama Desert to reach the men, said J. Davitt McAteer, who was appointed to investigate the causes of a blast at Massey Energy Co.’s Performance Coal operation in Montcoal, West Virginia, which killed 29 people in April.

The technique of lifting workers from a man-sized hole first proved successful in 1963 after David Fellin and Henry Throne were pulled out of the Sheppton coal mine in Pennsylvania after being trapped for 14 days. A similar rescue effort at a coal mine in Crandall Canyon, Utah, ended in failure after six miners and three rescuers were killed, said McAteer, who is not involved in the Chilean rescue effort.

Advice From NASA

As the drilling takes place, Chile is seeking advice from the U.S.’s National Aeronautics and Space Administration and its domestic Navy on how to maintain the health of the 33 miners. They were discovered Aug. 22 after being trapped since Aug. 5, when the only access to the mine collapsed.

The miners’ only contact with the outside world is through six-centimeter-wide drill holes that were used to discover them and through which they receive food, water, medicine and games such as dominoes and ludo. A third such hole reached miners on Thursday, and that is where the second escape shaft will be drilled.

Video footage released Aug. 26 night showed most of the gaunt and bearded miners in good humor and sending messages to their families. Five of the workers who showed signs of depression in the mine improved their spirits after rescue workers sent down more entertainment materials, Health Minister Jaime Manalich said today in televised remarks.

The mine is owned by Cia. Minera San Esteban Primera SA. A judge in northern Chile froze company funds at the request of a lawyer representing families affected by the accident, according to a statement posted on Chile’s judicial website.