DEHRADUN: It took 400 hours of hard work by 250- member strong rescue team for the successful evacuation of 41 labourers trapped in the Silkiara-Dandalgaon double tube under-construction tunnel. But it was the talent and experience of rat-hole miners that made the difference.
Colonel Deepak Patil, in-charge of the rescue team, told this paper,“ A team of rat miners was finally engaged in the operation after the Auger machine got stuck inside the tunnel on November 26”.
‘Rat Miners’ is a team of experts who specialise in high-speed excavation. The Army too assisted this special team.
“Manual drilling and excavation using rat-hole mining method began on Monday”, a person familiar with the matter said, adding that “six rat-hole mining experts have been deployed for rescue operations.”
National Disaster Management Authority (NDMA) member Lt Gen (Retd) Syed Ata Hasnain said that rat-hole miners did a phenomenal job by digging 10 metres in less than 24 hours.
“Rat-hole mining may be illegal, but rat miners’ talent and experience which is being used, it is their capability which is being used,” he said in a media briefing here.
The National Green Tribunal in 2014 imposed a ban on coal mining using the rat-hole mining technique in Meghalaya.
Rat-hole mining involves digging of narrow tunnels, usually 3-4 feet high, for workers to enter and extract coal. The horizontal tunnels are often termed “rat holes”, as each just about fits one person.
At the Silkyara tunnel in Uttarkashi, at least 12 experts have been called by Trenchless Engineering Services Pvt Ltd and Navayuga Engineers Pvt Ltd to deploy the rat-hole mining technique horizontally in the collapsed part of the main structure.
They have come from Delhi, Jhansi and other parts of the country. NHAI member Vishal Chauhan said: “This is a special situation, this is a life-saving situation ...they are technicians helping us,” he said. Twelve rat-hole mining experts were involved in the horizontal excavation.