Rescuers to drill from top of tunnel to save trapped workers in Uttarakhand
The fate of the workers trapped in a collapsed under-construction tunnel in Uttarkashi hung in the balance on Saturday as the rescuers trying to reach them began working on an alternative plan — after abandoning the first two — on the seventh day of the operation, while also exploring options to ensure supply of food and essential medicines to the 41 people does not halt.
The new plan involves creating an alternative route at the top of the mountain to enable drilling vertically from a pre-identified spot on the tunnel to a depth of about 103 metres where the workers are stuck, officials explained.
Early on Saturday morning, a new auger machine arrived at the site but remained unused after fears of further damage to the tunnel following a loud crack heard the previous day while drilling a hole through the 65-70 metre wall of debris.
All options to rescue the workers are being explored, Bhaskar Khulbe, former adviser to the Prime Minister’s Office, said.
“We are exploring as many options as possible to rescue workers. It is our priority to reach those who are stuck for days here. We don’t lack any resources, options and ideas, we just need some coordinated action and we are trying to make teams and reach there somehow,” Khulbe, who arrived on the scene on Saturday, said as he sought to reassure locals.
The construction workers have been trapped since Sunday when a portion of the 4.5-km tunnel they were building collapsed about 200 metres from the Silkyara entrance in the Uttarakhand district. The tunnel is part of the busy Chardham all-weather road, a flagship project connecting various pilgrimage sites.
The National Highways and Infrastructure Development Corporation Limited (NHIDCL), which is overseeing the rescue work, also reached out to ONGC, the Indian Army’s Engineering Corps, and the engineers who built the Atal Tunnel in Himachal Pradesh, for assistance.
“Four possible points where drilling can start have been identified (on top of the tunnel). We have also started making the approach road on the hill top for the machine,” a Rail Vikas Nigam Limited (RVNL) official, involved in the planning of the operation, said.
Officials held out hope that a Border Roads Organisations (BRO) road to create an alternative route to the tunnel would be ready by Sunday afternoon and the rescue mission that had been stalled since Friday could finally resume.
“This track is about 1,000-1,100 metres long. Simultaneously, we are also conducting a survey to know how much time it will take. As per our calculations, the track should be ready by tomorrow afternoon,” news agency PTI quoted BRO’s Major Naman Narula as saying.
But the new plan is not devoid of its own risks.
“Done safely and successfully, this will mean at least another five days to a week,” the RVNL official cited in the first instance said.
“We will use Odex (Overburden Drilling Excentric) method, which is a drilling technique specifically designed for drilling through overburden soil conditions, where unstable ground and loose formations make traditional drilling methods challenging,” this official said.
Officials also fear further damage to the tunnel during drilling may hinder efforts and lead to more debris falling on the trapped workers.
Expressing these concerns, NHIDCL director Anshu Manish Khalkho on Friday said, “Initially, we did not conduct this survey as we believed we could navigate through the 60 metres of debris. However, based on a previous survey, we identified that a minimum drill depth of 103 metres will be required for this plan C. Implementing a 103-metre vertical drill poses risks as it may lead to additional debris falling.”
Meanwhile, concerns over the health of the 41 people — the number of the trapped workers was revised late on Friday night, triggering concerns over negligence by the construction company – continued to rise.
As of Saturday afternoon, the workers were reportedly safe, and were being supplied food items like roasted chickpeas, puffed rice, dry fruits, multivitamins, and glucose.
Authorities were looking to insert a 100-metre long pipe, about 5 inches in diameter, for dropping food, water and medicines in the event of the horizontal pipes currently being used suffer damage due to a further cave-in or landslide.
“It has been decided to build an alternative food supply pipe for emergencies. Experts feel that vertically inserting a pipe measuring not more than 4-inches from the ceiling of the tunnel in the mountainside will not lead to a landslide. It will be a thin pipe, inserted for emergency, just to send food and water until they can be brought out,” said an official said after a meeting of officials from the PMO, state government, and experts in the morning.
“Seniors officers of different agencies such as NHIDC, NDRF, NDMA, ONGC, Army Engineering Corps, Uttarakhand state government have joined a WhatsApp group. While the NHIDC is working to build the passage, the top officials of all these agencies will ensure that any material is made available immediately with the help of Indian Air Force (IAF),” the official added.
“The joint agencies will coordinate with the Colonel Deepak Patil, who is overseeing the operation. The highest levels of government will ensure that any help needed at the site is provided,” the official said.
Separately, officials have also decided to extend the existing horizontal pipes (its mouth is currently inside the tunnel, the other end is with the trapped workers) to a point outside the tunnel so that even if there is a cave-in and the rescuers cannot enter the tunnel temporarily, they are able to send essential supplies of the workers.
The restlessness at the site of the accident grew.
Co-workers of the trapped people held a protest at the site, accusing the authorities of negligence and delays in the operation.
“They (rescue teams) have been testing our patience. They have been just experimenting…by bringing new machines, one after another,” Mrityunjay Kumar, a construction worker from Bihar, said.
“There is no work going on inside the tunnel. Neither the company nor the government is doing anything,” said a tearful Haridwar Sharma, whose younger brother Sushil is among those inside the tunnel.
“All we are getting are assurances from authorities that the trapped labourers will be rescued. It has been nearly a week,” Sharma, who is from Bihar’s Rohtas district, said.
Rescue operations stalled around 2.45pm on Friday. During the positioning of a fifth pipe, a big cracking sound was heard in the tunnel upon which rescue operation was suspended immediately, a statement from the NHIDCL tasked with the construction of the tunnel said in a statement on Friday night.
There was a brief pause in the drilling on Friday morning as well, when the augur machine, flown in from Delhi, sustained damages after drilling through nearly 24 metres. This plan involved drilling through the debris to push pipes — 800mm and 900mm in diameter — one after the other to create a passage for trapped workers to crawl out of.
Before that, as part of Plan A rescuers tried to dig through the rubble using heavy excavator machines, but loose rock and sand collapsing from the roof of the tunnel impeded progress.
Considering the delays and the sensitivity of the operation, authorities have now decided to work simultaneously on five plans.
“The experts were one in their view that rather than working on just one plan we should work at the same time on five plans to reach the trapped workers as early as possible,” Khulbe, now OSD in the Uttarakhand government, said at a press conference in Silkyara.
Read here: ‘Don’t tell mom I am stuck here’: Worker trapped in Uttarkashi tunnel tells brother
The five plans include drilling from one end to the other on both Silkyara and Barkot sides, vertical drilling from the top of the tunnel and perpendicular drilling, he said.
Meanwhile the authorities have also decided to weld the large diameter pipes and prepare an escape route for the people working at the site. With rescuers at the tunnel fearing that they themselves could be trapped if there is a further cave in, the pipe will be laid from the mouth of the tunnel to the spot where they are working to build the escape passage.