So close yet so far: Obstructions put off Uttarkashi tunnel rescue by some hours

The plan has been to drill through the roughly 55 metres of debris, insert pipes in the space that’s created, and pull the men out.

According to officials in Uttarkashi, they eventually managed to clear the obstruction and restarted drilling, but after 1.8 metres, another similar hurdle appeared to be blocking their path.

“The obstruction (on Wednesday) was a lattice girder that was at the mouth of the pipe that we had thrusted till 45 metres. That has been successfully removed. The entire work is now focusing on the reassembly of the pipe for a fresh push of six metres, which takes (including the assembly, welding, and pushing) roughly around four hours,” said Bhaskar Khulbe, a former adviser to the PMO and Officer on Special Duty to the Uttarakhand tourism department.

“Our calculation as of now is that we need to negotiate a (total) distance of 60 metres to safely reach our trapped workers. This means 18 metres more, roughly about 14-15 hours, unless something else happens,” said Khulbe in the afternoon. He said that it was at the mouth of the pipe that the lattice girder had caused an obstruction, and the auger had been repaired to the extent that it could be. He said rescuers have taken corrective measures to improve the movement of the auger inside.

Later in the day, Neeraj Khairwal, Secretary of the Uttarakhand Government, said that when the machine hit the metal girders, they had to withdraw it all the way back to understand the issue. The process itself took around two hours.

“We then sent our experts (into the pipes) to remove the issue. However, it was a very tough job as gas cutting in the closed area of the pipes creates a lot of heat. Two teams failed to do that. Then the Trenchless Engineering company called their experts, Praveen and Balvinder, who stayed inside for over two hours and cut the girders. After cutting through the metal, the old assembly line of the machine was established and since then we are inside by 1.8 metres more,” said Khairwal.

He said that late in the afternoon, they again faced some hurdles, but instead of pushing further, the experts decided to inspect the hurdle to clear the path for further drilling.

Mahmood Ahmad, the Managing Director of National Highways & Infrastructure Development Corporation Limited, said that in case of too much pressure build-up again, they will need to repeat the process of bringing the machine all the way back and analysing the blockage.

Chief Minister Pushkar Singh Dhami and Union Minister of State General (Retd) VK Singh also reached Silkyara on Thursday to take stock of the operation. During the visit, Dhami paid obeisance at the temple of Baba Boukhnag located at the entrance of the tunnel and wished for the speedy rescue of the workers.

In Delhi, National Disaster Management Authority member Lt General (Retd) Syed Atta Hasnain said that if no further obstacles come in the way, then horizontal drilling through the auger machine can help rescuers reach the men by middle of Friday.

“If all goes well, I gave you the rate of advance, an auger theoretically drilling through, moving through – no obstacle comes in the middle, no rockfall, no concrete, and no iron girder in the middle – four to five metres per hour. We should be able to achieve this in about five hours maximum,” Hasnain said, responding to a question.

However, National Highways Authority of India member (admin) Vishal Chauhan clarified that auger drilling is one part of the process, but the welding of two pipes takes four-five hours.

“So, auger drilling may do four-five metres in an hour but pipe pushing (takes) again four hours… Again we have to add another pipe; another four-five hours. So, it is a time taking process,” Chauhan said.

After Chauhan clarified, Hasnain said, “Keeping all this in mind, ideally, by tomorrow midday, we should definitely be able to reach the spot, as I told you without any obstacle in your way.”

“This is purely through process and then proving. It’s not that you have gone through and you say that everything is hunky-dory. You have to always prove that there is no danger, there is no vibration and things which are taking place. Then at the same time, keeping in mind the other options, they can extend as much as 45 days. Those options (include) blasting, sideways drilling through the mountain side. All of that can go as much as 45 days and that is also in ideal conditions without any obstacle being encountered,” Hasnain elaborated.