Rescue teams at the collapsed Srisailam Left Bank Canal tunnel in Telengana are staring at a herculean task of clearing around 10,000 cubic metres of mud sludge to reach the final 40m where eight workers are suspected to be trapped.
The sludge has accumulated to a height of 3.1m and the operation is being termed “most challenging and complicated”, reported the Deccan Herald.
Even after five days since a part of the under-construction tunnel at Domalapenta in Nagarkurnool district collapsed on Feb 22, the eight people involved in the excavation work have not been located.
With no space to make a turn inside, it’s difficult for trucks to go in and transport back the sludge.
The conveyor belt that was attached to the boring machine (TBM) that was inside the tunnel has been badly damaged. It is also obstructing the rescuers’ path to the end point.
Marine commandos of the Indian Navy were roped in on Wednesday to help.
“Initially, the plan involved sending a JCB (digger) inside the tunnel to remove the mud. But how will the machine navigate inside in a 360-degree manner?” a senior Telengana government officer told the Deccan Herald. “There is already a significant amount of water surrounding the area, making it impossible for the machine to manoeuvre.
“There is a risk of further collapse of the upper surface if the silt starts clearing, which may lead to a bigger disaster. On top of that, the heavy tunnel boring machine is filled with concrete debris and iron parts. It is unimaginable how the 10,000 cubic meters of mud can be brought out through trucks that can each carry only around five cubic metres at one time.
“Without clearing the mud, reaching the last 40m where the men are suspected to be trapped is not possible.”
The Hindu reported that a 20-member team of experts managed to reach close to the end point of the tunnel on Wednesday but had to turn back as “there was a lot of debris”.
“They are working out how to go about clearing the debris,” Nagarkurnool Superintendent of Police Vaibhav Gaikwad told news agency PTI. He added that the team could not find any missing workers.
Telangana Irrigation Minister N. Uttam Kumar Reddy said the boring machine that is stuck inside will be cut into pieces by using gas cutters and removed. After this, army, navy and rescue teams will make another effort to rescue the missing people, without compromising their own safety.
NDTV reported that about 800 people were working on the project, out of whom 300 are locals and the rest from states such as Jharkhand, Odisha and Uttar Pradesh.
The trapped persons have been identified as two engineers, two operators and four labourers.
