At the scene of the rescue operation on Monday, former Director General of Border Roads Organization Harpal Singh said that vertical drilling had been completed up to 31 meters above the Silkyara-Barkot tunnel.
Drilling 86 meters vertically is required to provide an escape route for the 41 workers who have been imprisoned for the last 15 days. The second alternative is to lay pipes with a diameter of 1.2 meters vertically through the roof of the tunnel.
According to him, plans are also in place to begin manually digging horizontally within the main tube. With the auger equipment broken, rescuers had to physically dig 10 to 12 meters through the debris.
Pipe frames with a diameter of 800 mm are ready. We shall advance progressively by 0.5 to 1 meter. A 10-meter length may be completed in 24 to 36 hours if everything goes according to plan and there are no problems, he added.
The 25-ton auger drill, which resembles a corkscrew and has a rotating blade at the front end, became stuck Friday night while boring through the rubble, prompting authorities to give up on the equipment.
On Sunday night, portions of the auger were allowed to be withdrawn from an area measuring 8.15 meters. To allow for hand drilling and pipe pushing, which is the last stage with around 12 meters remaining, the machine’s shaft and fins had to be fully removed from the debris. The machine has now been disassembled in its entirety.