Indian army engineers dig by hand to free 41 trapped tunnel workers
SILKYARA TUNNEL, India—Indian military engineers were preparing to dig by hand Monday to reach 41 workers trapped in a collapsed road tunnel for 16 days, a rescue operation hit by repeated setbacks.
Soldiers plan to use a so-called “rathole mining” technique, digging by hand to clear the rocks and rubble over the remaining nine meters, with temperatures plummeting in the remote mountain location in the Himalayan state of Uttarakhand.
Last week, engineers working to drive a metal pipe horizontally through 57 meters of rock and concrete ran into
metal girders and construction vehicles buried in the earth, snapping a giant earth-boring augur machine.
“The broken parts of the auger (drilling) machine stuck inside the tunnel have been removed,” senior local civil servant Abhishek Ruhela told AFP on Monday, after a specialized superheated plasma cutter was brought in to clear the metal.
“Preparations are being made to start manual drilling work,” he added. “Indian Army engineering battalion personnel, along with other rescue officers, are preparing to do rat-hole mining”.
Engineers in the bitterly cold conditions will use manual drills to clear the route, a tough task in the narrow pipe, just wide enough for a man to crawl through.
In a separate effort, vertical drilling has reached more than a quarter of the 89 metres down to the men, a risky route in an area that has already suffered a collapse.
A drilling machine was brought up to the forested hill above the tunnel on a specially-constructed track.
“Vertical drilling is going on at a fast pace,” with teams having reached 19 meters by late Sunday, said Mahmood Ahmed, a top official in the national roads ministry.
Work is ongoing at “full speed but with caution,” he added.
Digging, blasting and drilling have also begun from the far side of the road tunnel, a much longer third route estimated to be around 480 meters.
The 41 construction workers have been trapped in the Silkyara road tunnel since November 12.
Efforts have been painfully slow, complicated by falling debris and repeated breakdowns of drilling machines.