With the auger machine encountering hurdles in the rubble time and again, rescuers are considering switching over to manual drilling at the Silkyara tunnel where 41 labourers have been trapped for the past 13 days, officials said on Saturday.
Drilling at the collapsed portion of the tunnel to rescue the trapped men was halted again on Friday night, in yet another setback to the multi-agency effort.
An official said the auger drilling machine faced a hurdle, apparently a metal object, a little after drilling resumed Friday, a day after officials had put the operation on hold following technical problems.
With one hurdle or the other not letting the auger machine drill further and lay steel pipes through the rubble to prepare an escape route for the trapped workers, the option of manual drilling is being considered, an official said.
However, he said, manual drilling takes longer time.
The multi-agency rescue effort began November 12 when a portion of the under-construction tunnel on Uttarakhand's Char Dham route collapsed following a landslide, trapping workers inside.