A section of the tunnel collapsed at the 13.9 km point inside the tunnel 11 days ago
Hyderabad: The spirits of rescue teams at the SLBC tunnel soared on Tuesday with the restarting of the conveyor belt system that can carry away up to 800 tonnes of debris and silt every hour from the disaster site.
The system, originally designed to carry rock debris generated when the tunnel boring machine works, has turned into a lifeline of sorts and will help remove around 10,000 cubic metres of rock and soil that crashed into the tunnel when a portion of its roof collapsed on February 22.
“The conveyor belt is now functional for a distance of 10 km,” said special chief secretary Arvind Kumar, supervising the rescue efforts at the SLBC tunnel inlet site in Domalapenta in Nagarkurnool district. “Work to restore the system in the final 3 km inside is going on and we hope that entire system will be ready to be put to use from Wednesday,” he said.
A section of the tunnel collapsed at the 13.9 km point inside the tunnel 11 days ago. The impact of the tonnes of soil, rocks and water that gushed in broke the tunnel boring machine (TBM) into two, pushing the rear of the machine some 70 metres in a matter of seconds. Eight workers have been missing after the accident while 42 others managed to scramble to safety and exit the tunnel, chased by the water and silt that was pouring down at that time.
“Once the conveyor is fully ready, we will be using an excavator to lift the silt and use the belt for faster removal of debris. This will also help in speeding up the search for the missing persons.” Kumar said.
Though seepage of water, continuing at a rate of around 5,000 litres per minutes, is proving to be a hurdle, a fully functioning pumping system has been keeping up with the inflows. However, since the accumulated silt – varying in height between 3 and 8 metres – covering the final 200 metres towards the collapsed section can be reached with an excavator for faster evacuation of the material, efforts are on to remove the cut sections of the TBNs’ rear portions, which too is expected to pick up some speed from Wednesday.
Officials said that in the meanwhile, workers including members of the rat Miners team, have been digging through the silt at the locations where a National Geophysical Research Institute team suggested the possibility of finding the workers. Four of the eight such spots have not yielded any result and digging is going in the other four spots. We hope we can find the missing persons, at least some of them, by tomorrow or the day after,” an official supervising the digging said.
