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  • Over 400 hours, multiple setbacks: A timeline of how the Uttarakhand tunnel rescue op transpired | India News

Over 400 hours, multiple setbacks: A timeline of how the Uttarakhand tunnel rescue op transpired | India News

After a 17-day rescue operation that tested the grit of men on both sides of the 57 metres of debris, the 41 workers trapped in Uttarakhand’s Silkyara-Barkot tunnel were evacuated on Tuesday.

Around 8 pm, the first worker was taken out and ferried to a medical centre in an ambulance. Officials said it took 3-5 minutes for each worker to be pulled out on stretchers fitted with wheels.

Here is a timeline of the 400-hour rescue operation:

📌 November 12: 41 workers get trapped as the Silkyara-Dandalgaon under-construction tunnel on the Brahmkhal-Yamunotri highway partially collapses due to a landslide. With the NDRF, SDRF, BRO, project executing agency NHIDCL and ITBP commencing rescue operations, arrangements are made to supply oxygen, electricity and food to the trapped men through air-compressed pipes.

📌 November 13: The workers are reported to be safe after rescuers succeed in establishing contact with them through a pipe being used for oxygen supply. Efforts are made to prepare a safe passage to reach the men by removing debris and installing setting plates. However, fresh rubble falling from above results in debris accumulated in an area of around 30 metres spreading to 60 metres, hampering the process

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📌 November 14: Resorting to the “trenchless” technique, auger machines used for horizontal drilling reach the site to insert steel pipes of 800- and 900-millimetre diameter through the rubble. About two metres of pipe is inserted among the debris, but the machine is not able to drill through the rubble. Two labourers sustain minor injuries as more rubble falls from the cavity created by the cave-in.

📌November 15: The rescuers bring in a state-of-the-art auger machine,  which is airlifted from Delhi using two Hercules C-130 planes and brought to the spot in three parts, and later assembled.

📌November 16: The high capacity machine is assembled and installed, as it starts drilling past midnight. It shows promise as it enters around 3 metres within half an hour. By 4.30 pm, it had drilled 9 metres.

📌 November 17: The machine continues drilling and four MS pipes are inserted. However, it faces trouble at the 22-metre mark ast it struggles to move forward and its bearings get damaged. A backup machine is airlifted from Indore, to arrive the next morning. It is confirmed that around 2.45 pm, during the positioning of the fifth pipe, a loud sound was heard by the team. It is later explained that the same symptoms were observed in previous occasions of the collapse, leading to the operation being suspended.

📌November 18: Drilling does not resume as experts feel the vibrations created by the American auger inside the tunnel might cause more debris to collapse. Meanwhile, a team of officials from the PMO and experts decide to work on five evacuation plans simultaneously, including drilling a vertical tunnel from the top of the mountain.

📌 November 19: Drilling remains suspended as Union minister Nitin Gadkari reviews the situation, confirming that drilling horizontally with the auger machine seemed to be the best solution. Five agencies – Oil and Natural Gas Corporation, Satluj Jal Vidyut Nigam, Rail Vikas Nigam Limited, National Highways and Infrastructure Development Corporation Limited, and Tehri Hydro Development Corporation Limited – are assigned responsibilities.

📌 November 20: A six-inch pipe to supply essential commodities passed through the debris and reached the workers. Meanwhile, PM Narendra Modi speaks to CM Pushkar Dhami over phone to take stock of the operations.

📌 November 21: At 3.45 am, an endoscopic camera reaches the other end of the pipe, establishing the first visual contact with the men. The workers, wearing yellow and white helmets, can be seen receiving food items sent to them through a pipeline and talking to each other. The best bet remaines drilling through the Silkyara side.

📌 November 22: Drilling restarts around 12.45 am, and by around 11 am, the machine drills through around 39 metres. By 4 pm, the machine is around the 45-metre mark with just around 10-12 metres of debris remaining. Ambulances are kept on standby.

📌 November 23: Rescue operations to evacuate 41 trapped workers enters the final stretch early morning after a late night hitch wherein the auger machine drilling the escape passage through the rubble hit a hard obstacle. All arrangements have been made to provide immediate medical care to the 41 trapped workers after they are evacuated, officials say. But boring through the rubble is halted again after cracks appear in the platform on which the drilling machine rests.

📌 November 24: The National Disaster Management Authority (NDMA) say that about 15 metres are still to be covered to reach trapped workers.  The 25-tonne machine is restarted and drilling is resumed. However, in a fresh hurdle, the drill hits a metal girder halting the operation again.

📌 November 25: Rescuers face a significant setback with the auger joint of the drilling machine breaking inside the rescue pipes and blocking the passage. This forces officials to consider switching to options that could drag on the rescue by several days, even weeks. Mobile phones and board games are sent to the 41 trapped workers to alleviate their stress.

📌 November 26: A plasma machine from Hyderabad begins work to cut and bring out the broken auger machine. After the drill blade is removed, rescuers plan to manually dig through the remaining debris to reach the trapped workers. Vertical drilling, considered to be the second best option, also starts from the top of the tunnel, completing 19.2 metres of digging.

📌 November 27: Rat-hole mining experts help the rescuers in digging horizontally around 10 metres of rubble. Meanwhile, the vertical drilling from above the tunnel continues, reaching 36 metres of depth.

📌 November 28: Rescue workers break through the last stretch of the rubble at about 7 pm as as miners dug through the last 12 metres. All 41 workers are successfully brought out and taken to a medical centre in ambulances which had been lined up at the mouth of the tunnel.

(With inputs from PTI)

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