Rescue mission to save men trapped in Himalayan tunnel don't 'get much harder', Australian expert says
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The Australian expert at the forefront of an operation to save 41 workers trapped in a collapsed tunnel in India says rescue missions don't "get much harder".
"Because we are up in the Himalayas, and the Himalayas are technically a very fresh mountain range, which means they're falling apart," Arnold Dix, a professor of engineering and the president of the International Tunnelling and Underground Space Association, told the ABC's The World program.
"That means when you put a tunnel through, you've constantly got this risk that there's going to be a collapse and so as engineers you're fighting that risk."
Rescuers, including Professor Dix, have been battling to pull out the men stuck in the 4.5-kilometre tunnel in the mountainous Uttarakhand state since it caved in early on November 12.
Authorities have not said what caused the collapse, but the region is prone to landslides, earthquakes and floods.
"Thousands of tonnes of rock have fallen in part of the tunnel and essentially created a tomb," Professor Dix said.
The men have about 2km of space where they have been trapped in the tunnel, which is 13 metres wide and 15 metres high.
They are warm and have light, and have been kitted out with the essentials — oxygen, food, water and medicines — via a pipe.
Professor Dix praised the "awesome" local team of "seasoned Himalayan engineers and technicians" whose first action was to burrow a pipe 12 centimetres in diameter down to the trapped men.
"That little pipe became a lifeline," Professor Dix said.
"People could yell into it — so you could hear someone was alive on the other side — and pass dry food and medicine."
A second, larger pipe was run down through the thousands of tonnes of collapsed rock in the past few days after a few unsuccessful attempts.
"For the first time they've been able to get cooked food," Professor Dix said.
The trapped men can also communicate via walkie-talkie with their families who are waiting anxiously — some camped outside.
Professor Dix said the rescue team was trying to create "doors" to reach the men.
Drilling through the tonnes of rock to make a "front door" was risky as the area where the collapse happened is dangerously unstable and there is a large cavity above.
"So there's a risk it's going to collapse again," Professor Dix explained.
Authorities release a 30-second video showing the 41 men standing inside the collapsed highway tunnel in the Indian Himalayas as they communicate with rescue workers.
But there are other ways the rescuers are trying to enter.
Using advanced tunnelling equipment, they are attempting to make a "side door", and that was progressing well, Professor Dix said.
Teams are also attempting to drop vertically into the area where the men are.
"That's also got its challenges because you're on top of a mountain … and then you've gotta hit the target accurately," he said.
"Of course, you don't want to hurt anyone in there when you come through the roof."
Other crews are also working to come through from the other side of the tunnel.
Professor Dix said he was confident one of the "doors" would be opened and all the men would be able to be rescued.
"We know how to get them out, but we don't know when and we don't know which door will open," he said.
Rescuers had expected to break through early on Thursday as only the last third of the debris blocking the tunnel remained to be drilled through before an evacuation pipe could be pushed in and the men pulled to safety.
But rescuers encountered a lattice steel girder arch after drilling through about 45 metres of the estimated 60-metre stretch of debris, which required about six hours to cut and remove, according to an Indian official.
Local officials are hopeful of drilling through the remaining debris and reaching the men soon.
Ambulances have been parked near the entrance of the tunnel.
"Our calculation as of now is … roughly about 14 to 15 hours, unless something else happens, and we hope we will be able to do that," the official, who works on the tunnel project, told reporters.
"It is difficult to anticipate what more hurdles we might face," he said, adding that since the structure was not one of very hard rock, no major problem was expected, apart from another metal obstacle or rock.
Once the drilling is completed, officials plan to send rescuers through the evacuation pipe with stretchers on wheels to bring out the trapped men, they said.
On Tuesday, the first images emerged from within the tunnel, showing workers in white and yellow hard hats standing in the confined space and communicating with rescuers, after a medical endoscopy camera was pushed through a smaller pipeline.
Following the collapse of the tunnel, the National Highways Authority of India (NHAI) announced a safety audit of 29 tunnels it is building across India.
NHAI officials, along with others from the Delhi Metro Rail Corporation, will inspect ongoing tunnel projects and submit a report in seven days, it added.
These would include 12 tunnels in the Himalayan state of Himachal Pradesh, six in the Jammu and Kashmir region, and the rest in other states including Uttarakhand.
The construction spree has been questioned by some environmental experts who fear damage to the fragile Himalayan ecosystem and on the grounds of safety.
The collapsed tunnel is located on the Char Dham pilgrimage route, one of the most ambitious projects of Prime Minister Narendra Modi's government.
It aims to connect four important Hindu pilgrimage sites of North India through 890km of two-lane road — being built at a cost of $2.29 billion.
Environmentalists and residents have blamed rapid construction, including the Char Dham project, for land subsidence incidents in the region.
The federal government has said it employed environmentally friendly techniques in the design to make geologically unstable areas safer.
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