Tunnel rescuers look at 2 alternative plans

With the auger machine drilling through the debris of the collapsed Silkyara-Barkot tunnel suffering irreparable damage, authorities on Saturday were looking at alternative plans to evacuate the 41 workers trapped behind the what was nearly 60-metre-thick wall of rubble, in a setback that was poised to delay the rescue operation further.

- Amit Bathla

Officials are now shifting focus to two alternatives manual drilling through the remaining 10 or 12 metre stretch of the rubble or drilling down 85-90 metres from the top of the mountain.

Briefing mediapersons in Delhi, National Disaster Management Authority (NDMA) member Lt Gen (retd) Syed Ata Hasnain said, "This operation could take a long time."

At the site of the disaster, international tunneling advisor Arnold Dix said the workers will be out "by Christmas", attributing the delays to a "cautious approach" being followed in the operation.

Manual drilling would involve individual workers entering the already bored 47-metre stretch of the rescue passage, drilling for a brief period in the confined space and then coming out to let some else take over.

"Only one person who would have to go inside the narrow pipes can be at the forefront. One can't work for longer in such narrow passage. Shortage of oxygen and heat generated due to the use of machine is another problem," an RVNL official said on Saturday.

This, officials said, was likely to begin on Sunday, after the rescuers take out the blades of the auger machine that have been stuck inside the evacuation pipes that were being pushed through the debris to create a passage for the men trapped since November 12 to crawl out of.

HT on Friday reported that the drilling could not resume after being halted on Thursday afternoon when the platform on which the 25-tonne machine was mounted got destabilised after the drill bit damaged the steel pipes used in the construction of the tunnel. While the machine was disassembled and repaired, officials on Friday said that the evacuation pipe being pushed through the 800mm wide hole being drilled got warped, and the machine was stuck just 10 metres from breaking through.