Uttarkashi tunnel collapse: Drilling halted due to technical glitch

New Delhi: As the rescue mission to extract 41 trapped workers through the debris at the Silkyara tunnel in Uttrakhand entered its 13th day, the National Disaster Management Authority (NDMA) on Friday said no further progress has been made since Thursday in the drilling process.

However, a ground penetrating radar (GPR) indicated that there are no metal hurdles up to five metres ahead of the passage bored through the debris of the tunnel's collapsed portion. The GPR reading was a tough task as it required the team to enter the pushed pipe of 46 meters.

The trouble for the agencies involved in the rescue operation began in the afternoon on Wednesday after the start of drilling exercise. The machine encountered a metallic object (lattice girder rib) in the front of the pipe, and it created problems in further pushing of the pipe. Then, the cutting of metallic objects using gas cutters was completed.

Though there is no technical problem with the auger machine, the rescue workers needed to strengthen the platform on which it is mounted. The drilling machine's platform has been revamped and strengthened by shortening through the night, officials said, indicating that the drilling is likely to resume on Friday night for remaining 15 metres to reach the stranded workers.

Giving details of the operations, NDMA (member) Lt Gen Syed Ata Hasnain said that provided there are no further obstacles, the auger machine should be able to drill about 4-5 metres in an hour.

Hasnain also advised the media not to speculate on the timeline for completion of the rescue operations as it creates a wrong perception. At the time of filing this report, the latest available information was that the tasks like placing and positioning of the next pipe was under fast progress after completion of the welding joints. "It is a difficult and challenging operation," Hasnain added.

The NDRF on Friday conducted a mock drill on how it would take its wheeled stretchers through the chute being prepared to rescue the workers. An NDRF personnel went through the passage, pushing a wheeled stretcher tied to a rope at the end of the tunnel and was pulled back up after completing the stretch. He said there was enough room inside the pipes, and he had no difficulty breathing during the exercise. "Once the team reaches inside, they will examine the well-being of workers and prioritise their rescue depending upon their mental and health condition," added Hasnain.