Last Updated: November 28, 2023, 10:41 IST
A view close to the doorway of the Silkyara Tunnel throughout a rescue operation of 41 employees trapped in Uttarkashi district. (Credits: PTI)
The rat-hole mining methodology is a beacon of hope for the rescuers as they’re simply 5 metres away from the 41 employees trapped in the collapsed tunnel for 17 days
After all efforts to rescue 41 employees trapped contained in the collapsed Silkyara tunnel, a staff of “rat-hole miners” started drilling operations by way of the rubble.
Twelve rat-hole mining consultants will likely be concerned in handbook drilling and excavation horizontally by way of the final 10- or 12-metre stretch of particles of the collapsed portion of the under-construction tunnel on Uttarakhand’s Char Dham route.
The “rat-hole” methodology is a beacon of hope for the rescuers as they’re simply 5 metres away from the 41 employees trapped in the collapsed tunnel for 17 days.
The Rescue Operation So Far?
After over two weeks of the multi-agency rescue mission, officers have shifted their focus to two alternate options — handbook drilling by way of the remaining 10- or 12-metre stretch of the rubble or, extra probably, drilling down 86 metres from above.
The horizontal drilling that was being carried out by an enormous auger machine failed after the machine bought caught in the rubble on Friday, forcing officers to deal with an alternate choice — drilling down from above the tunnel.
The rescuers additionally started vertical drilling on Sunday afternoon after the auger machine failed to make any headways. About 40 per cent of the 86-metre vertical drilling required is now carried out.
For the horizontal through-the-rubble choice, officers determined that the ultimate stretch can be dealt with by way of a handbook strategy in which particular person employees will go into the escape passage with drills, in addition to gas-cutters to sort out obstacles like iron girders.
What is Rat-Hole Mining?
Rat gap mining is a controversial and unsafe observe of extracting small portions of coal from slim burrows or deep tunnels. It was prevalent in some states like Meghalaya.
The time period “rat hole” refers to the slim pits dug into the bottom, usually giant sufficient for one individual to match and extract coal, in accordance to The Indian Express.
Once the pits are dug, miners descend utilizing ropes or bamboo ladders to attain the top of the tiny holes. The coal is then extracted manually utilizing instruments like pickaxes, shovels, and baskets.
As per the report, there are two sorts of rat gap mining: facet chopping, the place the slim tunnels are dug on the hill slopes and employees go inside till they discover the coal seam and field chopping, the place an oblong opening is made, by way of which a vertical pit is dug and small rat-hole tunnels are dug horizontally to extract coal.
Risks in Rat gap mining
Rat gap mining is unregulated, lack security measures and trigger environmental issues. There aren’t any correct security provisions for miners like air flow, structural help and security gear.
In a outstanding tragic incident in 2019, 15 miners trapped inside a flooded “rat hole” coal mine died in Meghalaya’s East Jaintia Hills district, after remaining trapped for a number of days.
The observe has been a centre of criticism due to the damaging working circumstances, quite a few accidents and environmental harm. The methodology of mining has been banned by the National Green Tribunal (NGT) in 2014. However, in 2019, the Supreme Court put aside the NGT ban and allowed coal mining in Meghalaya by way of scientific mining strategies.
Why Rescuers Chose Rat-hole Mining Method?
Two groups of seven and 5 males who’re consultants in the strategy of rat-hole mining have been known as in by two personal corporations concerned in the rescue operation. The miners are probably to be divided into groups of two or three. Each staff will go into the metal chute laid into the escape passage for temporary durations.
Uttarakhand authorities’s nodal officer Neeraj Khairwal mentioned that the boys introduced to the positioning weren’t rat-hole miners however people who find themselves consultants in the method.
Rajput Rai, a rat-hole drilling knowledgeable, mentioned one man will do the drilling, one other gather the rubble together with his palms and the third place it on a trolley to be pulled out.
