Trapped Workers Safe, Focus Now On What Led To Uttarakhand Tunnel Collapse

The 41 workers were pulled out yesterday after a 17-day rescue operation which involved several agencies, drilling machines and rat miners, a profession that is now banned in India.

While the American drilling machine 'auger' managed to horizontally drill through nearly three-quarters of the debris, the last leg had to be drilled manually after the machine collapsed. A dozen rat miners, adept at burrowing in tight spaces, were then called in to take over and complete the rescue operation.

Situated about 30 km from Uttarkashi, the Silkyara tunnel is an integral part of the central government's Char Dham all-weather road project, which will stretch for about 889 kilometers across the fragile Himalayan terrain.

The project to build the tunnel is being carried out by Hyderabad-based Navayuga Engineering Company Limited, which has reportedly handled such projects before.

On November 12, a portion of the tunnel collapsed about 200 meters from the entrance, trapping the laborers working inside.

With the workers safe, the focus will now shift on what led to the collapse. The incident also highlights the risks of large scale development in the mountainous region which is seismic and prone to landslides.

While large projects are required to undergo an Environmental Impacts Assessment, the Silkyara Tunnel was exempt as it is divided into segments smaller than 100 km each. So the Supreme Court in 2019 asked an expert panel to suggest risk mitigation options.

The committee identified numerous problems. Its members warned that the nature of the soil, consisting in part of crushed rocks and limestone would exacerbate the existing risk of landslides and flash floods in Uttarakhand.

The government has said the National Highways Authority of India will carry out an audit of the 29 tunnels currently under construction across India.

Union Minister for Road Transport and Highways Nitin Gadkari said, "This was the first time such a mishap occurred. There is a lot we have learnt from this incident. We are going to conduct a safety audit of the tunnel, and also study how we could use better technology. Himalayan strata is very fragile and it is very tough to work there, but we will have to find solution.