Tunnel rescue: Robots deployed as final stretch proves hazardous amid structural risks

Hyderabad: Rescue operations at the Srisailam Left Bank Canal (SLBC) tunnel in Domalapenta in Nagarkurnool entered the 15th day. While efforts to locate the eight missing workers continued on Saturday, the Geological Survey of India has issued a warning about structural instability in the final 70 meters of the tunnel due to a roof collapse on Feb 22.
The GSI advised against human intervention in this section, prompting the state govt to deploy robots for the rescue operation in the unstable zone.
Irrigation minister N Uttam Kumar Reddy, who reviewed the ongoing operations, instructed rescue agencies to begin using robots equipped with advanced technology immediately. "We are utilising the best global technology to tackle the challenges in the final stretch of the 14-km tunnel," he said. The robots are equipped with high-resolution cameras, infrared sensors, and robotic arms to assess conditions and assist with the extraction of workers.
Special chief secretary, disaster management, Arvind Kumar said that initial silt removal from the tunnel boring machine was completed on Friday, and digging will continue into the second layer of the dismantled TBM on Sunday. "The two points identified by human remains detection dogs will be explored for further digging beyond 5 feet, as workers may be trapped in the second layer of TBM," Kumar told TOI.
Cadaver dogs, deployed by the Kerala-based team, detected a strong scent at a specific point, indicating the presence of three individuals. The rescuers will take the cadaver dogs inside the tunnel on Sunday again. Dewatering and desiltation are also taken up by the rescuers.
The rescue teams have managed to reach up to 13.95 km into the tunnel, with the final 50 meters remaining extremely hazardous due to oxygen depletion, water seepage, and debris from the collapsed TBM.
Uttam further explained that while the compressed air system is operational, the conveyor belt, which had collapsed during the accident, has been made largely functional except for the last 50-100 meters.
He said the state govt is providing full support to the families of the missing workers and has allocated Rs 4 crore for robotic rescue systems. Despite challenging conditions, Uttam reaffirmed the govt's commitment to completing the mission.
Uttam said the tunnel collapse incident, which he called a national disaster, remains unprecedented in the country. "We will continue the rescue efforts until every trapped worker is found and brought to safety," he assured.