 "Uttarakhand tunnel collapse")
On Monday, the 15th day of efforts to save 41 workers trapped inside the Silkyara under-construction tunnel in Uttarakhand's Uttarkashi began. The National Disaster Management Authority (NDMA) is working to retrieve broken parts of the auger machine while simultaneously conducting manual and vertical drilling to create an escape route for the trapped workers.
Meanwhile, two Border Roads Organisation (BRO) officials were injured after their SUV was rammed by a private bus near the Silkyara tunnel construction on Sunday. The accident occurred just half a kilometre away from the tunnel when three BRO officials were on the way to the site in their official vehicle.
Vertical drilling underway
On Sunday, rescuers drilled over 20 metres into the hill above the Silkyara-Barkot tunnel. Rescue workers have to drill down 86 metres to reach the tunnel.
Vertical boring would be over by Thursday if there are no hurdles, according to Mahmood Ahmed, managing director of National Highways and Infrastructure Development Corporation Limited (NHIDCL).
As the drilling continues, 700-mm wide pipes are installed to construct an escape passage. A thinner 200-mm probe is being inserted a short distance away. It has reached the 70-metre mark.
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Rescuers working on five different evacuation routes
The vertical approach was one of at least five options that had begun preliminary work a few days ago, as concern grew over the fate of the men trapped in the under-construction tunnel on Uttarakhand's Char Dham route.
The vertical boring option was chosen as the next best alternative following the latest in a series of hitches that beset the horizontal drilling effort from the tunnel's Silkyara-end, where rescue personnel faced an estimated 60-metre stretch of wreckage.
All you need to know about Uttarakhand tunnel collapse
1. On Diwali morning, a portion of the Silkyara tunnel collapsed, cutting off the exit of the 41 workers inside. The trapped workers are in a built-up two-kilometre stretch of the tunnel. Food, medications and other essentials are being delivered to them through a six-inch wide pipe. A communication system has also been set up, and families occasionally talk to them.
2. A huge auger drill, a corkscrew-like device with a rotary blade at the front end that is drilling into this stretch of debris, got stuck Friday evening, forcing officials to give up on the 25-tonne machine.
3. Individual workers have been entering this incomplete escape passage, in which a steel chute has been put to cut through and bring the stuck blades and the auger's shaft out in pieces.
4. On Sunday morning, a plasma cutter was airlifted from Hyderabad to supplement the gas cutter. A team from the Defence Research and Development Organisation (DRDO) and Army engineers from the Madras Sappers also reached Silkyara.
5. According to officials, only 8.15 metres of the 47 metres of the auger shaft that had been pushed into the debris remained to be cut and removed.
6. Once the auger is fully extricated, rescuers will adopt another fresh approach – manual drilling to clear the remaining 10 or 12-metre stretch of rubble.
7. One worker would enter the steel chute laid so far and operate the drill, while another man would send the debris out through a pulley in a time-consuming operation to be carried out in a confined space.
8. Meanwhile, work on other options is also in progress, officials said.
9. Beginning on Tuesday, rescue workers will start drilling a 180-metre alternate escape tunnel into the side of the hill. This process could take 12-14 days.
10. Officials said drilling is also being carried out from the Barkot-end of the tunnel, and the work has progressed about 10 out of 483 metres. This approach could take up to 40 days of drilling, officials said.
11. At a press briefing in Delhi, NDMA member Lt Gen (retd) Ata Syed Hasnain stated that the best option remained horizontal drilling, under which 47 metres of rubble had already been bored through.
12. Relatives of those trapped inside remained concerned after drilling with the auger machine was abandoned.
13. Union Minister of State for Road Transport and Highways V K Singh also revisited the disaster site on Sunday.
14. Uttarakhand Chief Minister Pushkar Singh Dhami met the family of trapped worker Pushkar Singh Eiri at his home in Tanakpur, assuring them everyone will be brought out safely.
