Drilling through the rubble to prepare an escape route for the 41 workers trapped inside the Silkyara tunnel was set to resume on Friday morning, a day after another snag hit the rescue efforts, an official said.
Former advisor to the prime minister's office Bhaskar Khulbe said the operation might successfully be completed by Friday evening if everything went well.
Citing the data scanned by a ground penetrating radar, there is no metallic obstruction up to five metres beyond the 46 metre point through the rubble.
The drilling machine's platform has been revamped and strengthened. Boring through the rubble with auger is likely to resume by 11.30 am, Khulbe told reporters at Silkyara.
"We have 12-14 metres more to go. And I hope if all goes well we might conclude the operation by Friday evening," he said.
"The situation is much better now. Last night, we had to work on two things. First, we had to revamp the platform of the machine... Parsons Company had done the ground penetration radar, through which we got to know that for the next 5 meters, there is no metallic obstruction. This means that our drilling should be smooth. When we were taking out the debris, we got two mangled pipes..." Khulbe said, adding that the trapped workers may be evacuated by Friday.
Notably, Friday marked the 13th day of the rescue operation to evacuate the trapped workers at the Silkyara tunnel.
On November 12, a portion of the under-construction tunnel from Silkyara to Barkot collapsed and debris falling in the 60-metre stretch on the Silkyara side of the tunnel trapped 41 labourers inside.
The workers are trapped in a 2 km-built portion, which is complete, including concrete work that provides safety to the workers.
On November 21, the NHIDCL resumed overnight the "horizontal boring operation from the Silkyara end" that involved an auger machine.
Images of an auger drilling machine facing obstruction to save workers surfaced on Thursday afternoon.
Some of the images from the tunnel showed the steel obstructing the free movement of the rescue pipe inside the tunnel and blocking the other side of the under-construction tunnel.
In one of the images, a shadow of a man is seen capturing the moments on his mobile phone. The debris was removed later, as per officials.
Rescuers, using an American Auger machine, resumed drilling on Tuesday and, by late night on Wednesday, drilled through 45 metres out of the 60-metre stretch of debris that blocked the Sikyara side of the under-construction tunnel stretching from Silkyara to Barkot.
With inputs from ANI
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