Indian authorities are exploring new ways to rescue 40 construction workers trapped underground for more than a week.
The workers became stranded when a highway tunnel they were building partially collapsed in the northern state of Uttarakhand last Sunday.
Although they are being supplied with food and water, a doctor said some of the men were getting ill, and had been vomiting and getting headaches.
State authorities have approved buying equipment and more manpower to implement options such as constructing escape tunnels from the left and right sides of the tunnel, officials said.
Drilling vertically from the upper hill - which is already being implemented - still remains a consideration.
Rescue teams had been drilling non-stop to reach the stranded workers since acquiring a high-powered drilling machine on Thursday, but given the fragile mountain terrain, there were concerns of more debris falling and further complicating the rescue efforts.
“We have decided to go with a pause-and-go approach to maintain the equilibrium,” Anshu Manish Khalkho, director of state-run highway management company National Highways and Infrastructure Development Corporation Limited (NHIDCL) said Friday.
Authorities in India previously revealed they had contacted the specialist teams in Norway and Thailand behind the successful rescue of 12 boys and their soccer coach from a flooded cave in northern Thailand in 2018.
In an emailed reply to CNN, officials from the Norwegian Geotechnical Institute (NGI) said their Indian partner, Indian Railways (RVNL) was currently on the ground and assisting with the rescue operation, but confirmed that members of the NGI were not involved at present.
Khalkho told reporters that rescuers, with the help of the high-powered drilling machine, have so far drilled about 25 meters (82 feet) inside the collapsed Uttarkashi tunnel – that’s about one-third of the way to the trapped workers.
The rescuers have 60 meters of debris between themselves and the trapped men. According to Khalkho, pipes designed for the rescue mission have been successfully inserted into approximately 25 meters (82 feet) of the debris. However, there remains an additional stretch to cover before reaching the 40 workers.
Pipes are being inserted into the freshly drilled hole and being welded together, Khalkho explained.
These interconnected pipes will provide an escape passage for the stranded men, enabling them to move beyond the section of the tunnel that has collapsed.
“It may look easy from the outside, but on-site we have to factor in the effects of the drilling vibrations on the fragile terrain,” Khalkho told reporters when questioned on the duration of the rescue mission, which entered its seventh day on Saturday.
He also confirmed that a backup drilling machine is being airlifted from Indore city in the central state of Madhya Pradesh in India, to assist in the rescue operations. Reuters reported Saturday that the initial drilling machine broke on Friday and needed to be replaced.
Separately, Uttarakhand’s Chief Minister Pushkar Singh Dhami also assured the press that the rescue work is on track with the “engineers and experts from NHIDCL working relentlessly,” and that Prime Minister Narendra Modi is “reviewing the situation.”
In an update Sunday, Dhami told Indian news agency ANI that “saving everyone’s life is our first priority…the state government is ready to give all the help required to all the agencies,” adding that expert teams are working on all the possibilities available to rescue the men.
Dhami later visited the site to “conduct on-site inspection and review of the ongoing relief and rescue work,” according to his post on X on Sunday. He was joined by India’s Minister for Road Transport and Highways Nitin Gadkari.
A special team from the Prime Minister’s office arrived at the tunnel collapse site to review the situation on Saturday.
The tunnel is part of Modi’s ambitious Himalayan Char Dham Highway project, a multimillion-dollar infrastructure plan to improve connectivity in the state of Uttarakhand and better access to important pilgrimage locations.
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