Uttarkashi, Nov 25 (PTI) 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.

Before the brief period of drilling on Friday, 46.8 metres of the 800 mm wide steel pipe had been pushed into the drilled passage -– out of the collapsed stretch estimated to be about 60 metres long. The six-inch wide tube for supplying food and other essential items to the workers had travelled 57 metres.

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.

The workers are in a built-up two-kilometre stretch of the tunnel. The trapped workers are being sent food, medicines and other essentials through the six-inch wide pipe.

A communication system has been set up, using the pipe, and the workers' relatives have spoken to them. An endoscopic camera was also pushed through this pipe, allowing rescue workers to see the condition inside. PTI COR ALM SMN SMN