Once the rescue pipe breaks through the debris at the Silkyara tunnel, National Disaster Response Force (NDRF) personnel plan to pull out the trapped workers one by one with the help of wheeled stretchers tied to ropes, a senior official said on Thursday.
Rescue operations to evacuate 41 workers trapped in the tunnel resumed on Thursday morning after an iron mesh that had come in the path of the auger machine drilling an escape path was removed.
NDRF Director General Atul Karwal, who was present at the site, said the force is fully ready for the evacuation.
The men have been trapped for 11 days after a portion of the under-construction tunnel on the Uttarakhand Char Dham route collapsed, cutting off its exit.
The NDRF men will go in through the pipe and once they reach the workers, they will use their equipment to start sending them out of the tunnel one by one, Karwal said.
The workers will lie upon low-height, wheeled stretchers and NDRF men will pull them out one after another using ropes, officials said.
But before that, the 800-mm diameter rescue pipe will be cleaned by the NDRF and SDRF personnel to ensure that no debris acts as an obstruction in the movement of the stretchers, the NDRF DG said.
Replying to a question, he said 800-mm diameter pipes are wide enough to accommodate the workers.
"These 800-mm pipes have a width of nearly 32 inches which is enough. Even if we get a width of 22-24 inches, we can pull out people through them. Our men have carried out rehearsals for the exercise," he said.
The iron mesh hurdle held up the drilling through the 57-metre stretch of the rubble of the collapsed section of the tunnel by six hours, dampening somewhat the previous evening's enthusiasm over an imminent rescue.
According to the NDRF DG, another six-metre steel pipe has been drilled through the rubble with the total length of the pipes reaching 48 metres.
"The next pipe is being welded now. We plan to drill two more pipes now so that we achieve a length of up to 60 metres through the rubble to get some extended space," Karwal said.
The NDRF DG said Uttarakhand Chief Minister Pushkar Singh Dhami talked to the trapped workers and they appeared to be in good spirits.
"People who work in tunnels are mentally tough and these people are aware of the huge endeavour being carried out to evacuate them. So they are optimistic," Karwal said.
