Uttarkashi tunnel collapse: 5-option action plan to rescue 41 trapped workers

Beneath the weight of the earth, forty-one workers are still ensnared in the cold shadows of the ambitious Char Dham Highway project in an embrace of darkness and silence.

The first visuals of workers trapped inside the collapsed Silkyara tunnel in Uttarakhand’s Uttarkashi surfaced on Tuesday morning, a day after rescuers pushed a six-inch-wide pipeline through the rubble – a breakthrough that would help them supply larger quantities of food to the labourers trapped inside for nine days.

Part of the Rs 12,000 crore infrastructure plan to improve connectivity between Char Dham sites, the tunnel collapsed at a distance of 160 metres from the entrance at Silkyara early in the morning on Diwali (November 12).

India Today’s OSINT team extensively studied public records to lay out the complete details of the five action plans underway by different government authorities to save the lives of 41 workers trapped in the darkness of the tunnel for over 200 hours now.

A team of the National Highway Infrastructure Development Corporation Limited (NHIDCL) will recommence the drilling from the mouth of the tunnel from the Silkyara side after it hit a snag on Friday once it dug 22 metres through the debris.

This was the first rescue (horizontal) pipe, work towards which has been rife with challenges. Workers were to crawl out of this 900m wide pipe but officials could only drill 22m when work was halted as the auger machine hit rocks and got broken or damaged. Simply put, an auger is a spiral-shaped tool that is used to drill holes into the ground and other surfaces or materials.

ROUTE 2: DRILLING FROM SIDEWAYS
In order to prepare an alternate life-saving escape, the Rail Vikas Nigam Limited (RVNL) has been given the responsibility of carrying out micro-drilling at a distance of 280m to the left of the tunnel entrance. Machinery has been sent for this operation from Nashik and Delhi. This horizontal tunnel will be 1.2 metres wide and 170 metres long.

ROUTE 3: VERTICAL DRILLING FROM ABOVE
A 1.2 metre-wide hole has been planned to be dug vertically from above the tunnel, which will be done for a distance of 320 metres from the entrance to reach the workers. The responsibility for this operation was given to the Satluj Jal Vidyut Nigam(SJVN) and the first machine to begin digging has already reached the site. Two more machines are expected to reach from Gujarat and Odisha in the next two to three days. This is to be the main vertical rescue tunnel.

ROUTE 4: 2ND VERTICAL TUNNEL FROM TOP

The Oil and Natural Gas Corporation (ONGC) has been tasked with digging another vertical tunnel towards the end of the tunnel at the 480m mark from the Barkot side. This tunnel will be nearly 325 metres deep and the machines for this operation were brought from the US, Mumbai and Ghaziabad.

ROUTE 5: HORIZONTAL RESCUE TUNNEL
A 483-metre-long yet narrower tunnel will be made through the Barkot end of the tunnel by the Tehri Hydro Development Corporation using the conventional drill and blast method. This is another backup plan and the work is yet to be started.

WHY RESCUE IS CHALLENGING?
The rescue operation has encountered considerable obstacles due to the heterogeneous soil conditions prevalent in the area. The stratification of the soil presents a dichotomy, with some zones characterised by a pliable composition while others exhibit a more rigid nature. This variance in the soil’s constitution significantly complicates the mechanical aspects of the operation.

Rocks: The most significant impediment in the rescue operation has been the persistent encounter with hard, unyielding rock formations. This has led to frequent collisions with auger machines, causing damage to their drills and consequently interrupting rescue efforts.

Terrain: The high-altitude location of the tunnel poses another substantial challenge, particularly in terms of accessibility. This factor has made the replacement of parts and machinery a time-intensive process.

Availability of parts: The need for specialized machinery and expertise for an operation of this scale has been a notable constraint. However, the situation has seen an improvement with the arrival of rescuers and equipment from Thailand and the United States at the site.

The minister for road transport and highways, Nitin Gadkari, said on Sunday that the rescue operation is challenging as the soil strata in the Himalayan region is not uniform. Horizontal drilling with the American auger is currently the fastest method to reach the trapped workers. However, the machine encountered difficulties when it hit hard rocks, leading to increased pressure and vibrations. As a safety precaution, the machine was temporarily stopped.

“We are working on six options simultaneously. The PMO is also closely monitoring the operation. Our biggest priority is to save all those who are trapped and as soon as possible, whatever is needed will be done,” he said.

NHIDCL director Anshu Manish Khalkho says, “DRDO has sent 2 robots weighing 20 kg and 50 kg, respectively. The robots move on the ground and the land works like sand. We are apprehending whether or not the robots will be able to move there.”

He further mentions, “All the machinery is coming, they are mobilised and will be here within a day or two… BRO is constructing roads wherever necessary on this end and the Barkot end. Roads are ready on both sides, now we are waiting for the machinery. The machines are very heavy, they cannot be airlifted.”

Uttarkashi district information officer, Kirti Panwar said, “Help is being taken from special teams from Norway and Thailand.” This is the company behind rescuing twelve boys and their soccer coach after nearly three weeks of being trapped inside the flooded Than Luang cave in 2018.

The Char Dham Highway project, spanning almost 1,000 kilometres, has caused substantial environmental repercussions, particularly through the extensive disturbance of mountainous ecosystems. Environmentalists have expressed concerns about the project’s extensive construction activities potentially exacerbating ecological vulnerabilities in the Himalayan region.

This area is already grappling with the ramifications of climate change, affecting millions. Specialists warn that the intensive drilling involved in the project could further destabilise the already delicate terrain, potentially leading to increased incidents of landslides and flash floods.