Amid the pause in the rescue operation at the Uttarakhand tunnel site due to issues with the auger machine, the team has initiated the planned “vertical drilling” process following the previous setback in horizontal drilling.

In a video released by news agency ANI, a section of the vertical drilling machine was observed being transported to the top of the Silkyara Tunnel as the efforts to rescue the 41 trapped workers continued.

According to National Disaster Management Authority (NDMA) member Lt Gen (retd) Syed Ata Hasnain, the current focus is on the vertical drilling, set to commence within the “next 24 to 36 hours” as machinery is being positioned on a platform above the tunnel. He emphasised the necessity for cautious operations, stating that “it will take time” to ensure the safe extraction of the trapped workers.

An estimated 86 metres of vertical drilling is required to reach the tunnel’s crust, after which it will be breached to access the trapped workers.

The rescue efforts faced a setback on Friday night when the auger drilling machine, attempting to drill through the debris, encountered an obstacle, presumably a metallic object. International tunneling expert Arnold Dix informed reporters that the auger had encountered multiple obstructions while attempting to create an exit passage. “Augering is finished… the auger is broken, destructed,” he said.

Uttarakhand chief minister Pushkar Singh Dhami mentioned on Saturday that the auger machine’s blades had become lodged in the debris, impacting the ongoing rescue attempts.

How will the rescue team carryout vertical drilling?

On Saturday morning, a big drilling machine was directed toward the hill overlooking the tunnel, targeting the two identified lowest points for vertical drilling. The Border Roads Organisation (BRO) has constructed a 1.5-km access road leading to the tunnel’s summit, preparing for the potentiality of vertical drilling, a plan in consideration for some time now.

Vertical drilling, a more intricate and time-consuming method, requires precision and caution due to the limited space atop the tunnel roof, as stated by International tunnelling expert a few days ago.

NDMA member said the ongoing operation as highly challenging. While two methods are presently in use, there is contemplation about employing a third method – the drift method – soon.

As of now, a horizontal drilling of 47 metres has been completed. The focus is on removing the damaged part of the auger machine and ensuring stability in the drilled structure. An 800-mm-wide steel pipe has been inserted into the drilled passage. The collapsed segment is estimated to be around 60 metres long.

Arnold Dix, an international tunneling expert, highlighted the breakdown of the auger machine, prompting rescuers to explore alternative options, including vertical and manual drilling, in their efforts to extricate the trapped workers.

41 workers trapped inside tunnel are stable

The workers are currently located within a constructed two-kilometre tunnel, receiving essential supplies like food, medicines, and other necessities through a six-inch pipe. Communication with their relatives and medical personnel is facilitated via walkie-talkies.

“The good news is that the 41 workers are stuck inside are stable. All the basic things are being sent. The relatives of the workers have also come, and they are talking to the workers. As far as the rescue operation is concerned, there are certain problems we are facing. There has been damage in the auger machine and some part of it has not come out,” NDMA member said.

The Chief Minister, urging the trapped workers to notify authorities of any issues, assured that their rescue is imminent. Stressing the nationwide solidarity with the workers, both the Central and State Governments prioritize a swift and secure evacuation.

Dhami emphasised sustaining the vigor of officials, experts, and everyone engaged in the operation. He also highlighted the importance of employing all available technology and resources to expedite the rescue efforts, even considering bringing in additional resources if necessary.

“Every possible support will be provided by the state government. Together we will complete the relief and rescue work very soon,” he said.