The GPR survey team, which used the ground-penetrating radar (GPR) technique, has been sent back to Delhi as manual drilling commenced on the 16th day of the rescue operations in Uttarkashi. The team discovered no heavy objects up to 5 metres in the rescue tunnel. The rescue work was temporarily stopped due to a broken Auger machine. Specialists will now utilize the manual drilling and rat hole mining techniques to remove the debris inside the pipe. Meanwhile, vertical drilling from the top of the mountain is also underway.

Ground Penetrating Radar (GPR), also known as Georadar, Subsurface Interface Radar, or Geo-Probing Radar, is a non-destructive technique used to create a cross-section profile of the subsurface without causing any damage. It is utilized to evaluate the location, depth, and presence of buried objects, as well as to study natural subsurface conditions and features.

Micro tunnelling expert Chris Cooper reported that the debris from the Auger machine has been cleared and manual drilling to reach the trapped laborers will commence soon. A team of 6 specialists will perform manual drilling and use a rat hole mining technique to remove the debris inside the pipe. The specialists will go inside the 800-mm pipe of the tunnel and employ tools such as shovels and blowers for oxygen.

Alongside the manual drilling process, a simultaneous vertical drilling process from the top of the mountain is also ongoing. Over 35 metres of vertical drilling work have been completed out of the required 86 metres to reach the trapped workers.

For more information, read the full article on The Economic Times website.