Uttarkashi: Drilling to create a vertical escape route for the 41 workers trapped inside the collapsed tunnel in Silkyara here for two weeks began on Sunday, an official said, a day after an auger machine carrying out horizontal drilling broke down.
"Vertical drilling has begun and (a stretch of) up to 15 metres has been drilled already," NHIDCL MD Mahmood Ahmed told reporters in Silkyara. If it does not face any hurdle, it will take nearly 100 hours to reach the trapped workers from the top of the hill above the tunnel.
Officials had said rescuers have to drill down 86 metres from above. The vertical drilling began a day the auger machine's blades got stuck inside the rubble, hindering the multi-agency rescue effort that began on November 12 when a portion of the under-construction tunnel on Uttarakhand's Char Dham route collapsed following a landslide, trapping the 41 workers inside.
The removal of the shaft and fins of the auger machine stuck in the debris is underway with plasma and laser cutters inside the tunnel, state nodal officer for the rescue operations Neeraj Khairwal said.
The vertical drilling is carried out by a team of Sutlej Jal Vidyut Nigam (SJVN). "We have given a proposal to the administration to do vertical drilling in 5 to 6 days; our team has done the survey for drilling; and apart from this, their drilling machine has also reached the spot to do the drilling. The vertical drilling will be done from the top of the tunnel and about 85 to 90 metres will have to be drilled, which will take about 5 to 6 days," an SJVN official said.
Meanwhile, experts are considering other options as well to save the 41 workers trapped inside the collapsed portion of the tunnel after the 25-tonne heavy auger drilling machine encountered insurmountable problems. The workers are safe and they will be rescued though it may take longer time than expected, sources said.
Officials roped in a plasma cutter from Hyderabad to remove the blades of the auger machine stuck in the debris. Apart from vertical drilling, laying pipes through manual drilling is among the options to prepare an escape passage for the trapped workers.
Technical glitches could drag the rescue operation for several days, or even weeks. The trapped workers are safe and are being sent food and medicines through a six-inch wide pipe.
The National Disaster Management Authority (NDMA) said the rescue operation may take a long time with horizontal drilling facing repeated hurdles. NDMA member Lt Gen (retd) Syed Ata Hasnain said that the front part of the auger machine was broken and efforts are being made to retrieve those from the tunnel.
"We need to have patience as it is a dangerous operation ... 'is operation main lamba samay lag sakta hai' (this operation may take a long time)," he said, without mentioning any timeline for the completion of rescue operations. According to Hasnain, this rescue operation is getting technically more complex every day.
Drilling at the collapsed portion of the Silkyara tunnel to rescue the trapped men halted again on Friday night after the auger machine engaged in drilling through the rubble to prepare an escape passage faced a hurdle, apparently a metal object, and busted.
Uttarakhand Chief Minister Pushkar Singh Dhami visited on Sunday the family of Pushkar Singh Airi, a worker from Tanakpur who has been trapped in the Silkyara tunnel for the last 15 days. The efforts to rescue the 41 workers trapped in the Silkyara tunnel on the Uttarkashi-Yamnotri road are still underway.
Speaking on the ongoing rescue operations, CM Dhami said that the auger machine cutting that got stuck in the debris of the Silkyara tunnel to rescue the workers is underway and will be completed soon. He said that manual drilling would begin after the auger machine was cut and brought out. "The plasma machine that has been brought from Hyderabad has started working since this morning. The cutting is going on rapidly. 14 metres more remain (to be cut), he said. The auger machine has to be cut and brought out. It seems that it will be completed soon, within a few more hours. After that, manual drilling will begin, CM Dhami added.
The NDMA member said 47 meters of horizontal drilling have been done, and efforts are on to remove the broken part of the auger machine. Rescuers are exploring other options such as drilling the remaining stretch manually and undertaking vertical drilling. On the vertical drilling option, the NDMA member said that machines are being placed on a platform on top of the tunnel and vertical drilling operations will start in the "next 24 to 36 hours".
Meanwhile, international tunnel expert Arnold Dix said that there would not be any new auger drilling machine and other methods would be used for rescue operations. "There are multiple ways. It's not just one way. At the moment, everything is fine. You will not see the augering anymore. Auger's work is finished. The auger (machine) has broken. It's irreparable. It is disrupted. No more work from Auger. No more drilling from the Auger. There will not be a new auger," Arnold Dix said.
"The mountain has again resisted the auger machine, so we're rethinking our approach. This is a decision that's been made by all the experts, including Indian and local experts. The Himalayan experts from India are providing us with all the information we need. I am confident that 41 men are coming home." added Arnold Dix.
"I'll just say that I've always promised that they'd be home by Christmas. If you remember right from the beginning, I've never been. It is a long time, and they're safe and they're well, and if we rush, we can cause another problem in there. So we're taking our time and being very considerate, and that's what all these meetings are at the moment. Of course, there'll be an announcement shortly about what we're going to do," he added. (With agency inputs)
Read More
Day 14 | Silkyara tunnel rescue: Auger machine 'damaged', manual drilling mooted to finish task
Uttarkashi tunnel collapse: How to ensure trapped workers don’t lose hope
