The relatives of the 41 trapped workers have been asked to “be prepared” as rescuers said they are just five meters away from them.
“Keep their clothes and bags ready,” officials told the families who have been keeping a vigil outside the collapsed tunnel.
Officials said the workers will be taken to a hospital in Uttarkashi after being rescued.
Anxious families are hoping to see their loved ones soon as the rescue operation is over.
A skilled team of workers started the manual drilling of the collapsed tunnel yesterday after parts of the broken drill – an auger machine – were removed from the tunnel.
Manual drilling is being carried out by “rat miners”- labourers used to drilling narrow shafts as part of a primitive method of coal extraction.
With about five meters left to reach the trapped workers and machine drilling options exhausted, manual drilling appeared to be the only way forward, the officials said.
That rescue operations were earlier suspended for three days when a US-made auger machine deployed to drill and push in pipes through the rubble to prepare an escape passage for the workers developed a snag
Manual drilling is a slow and labour-intensive process in which the rat-hole miners go through the huge pipe, drill manually and bring out the debris by shovels.
Asked if going through the pipes would be difficult for them, an official said that the workers will be provided with a helmet, a uniform, mask and glasses.
Over the past two weeks, repeated attempts to rescue the workers have failed because of challenges including the topography and the nature of rocks in the area.
Officials said the workers are mentally stable and physically fit despite being trapped for over two weeks. “They are adequately clothed and when we speak to them, they say they will walk out on their own. That’s the kind of mental strength they have,” an official said
The under-construction tunnel is part of the ambitious Char Dham project, a national infrastructure initiative to enhance connectivity to the Hindu pilgrimage sites of Badrinath, Kedarnath, Gangotri, and Yamunotri.