Telangana Tunnel Collapse: '8 Locations Identified With GPR To Track Trapped Workers,' Says NGRI Scientist

Hyderabad: Dr M Satyanarayana, Chief Scientist of the National Geophysical Research Institute, on Friday said that eight locations were identified with the help of Ground Penetrating Radars to track the workers trapped in the Srisailam Left Bank Canal (SLBC) tunnel collapse in the Nagar Kurnool district of Telangana.

"When signals were sent with the help of GPR to identify the tracks of workers in the Srisailam Left Bank Canal (SLBC) tunnel, strong signals were reflected from 8 places. We calculated the respective areas and depths and handed them over to the NDRF team," Satyanarayana told ETV Bharat, adding that he is hopeful that positive results will come soon.

The Chief Scientist was speaking to ETV Bharat after returning from the rescue operations. Explaining how the GPR works, he said," ‘We identify objects by sending electromagnetic rays through Ground Penetrating Radar (GPR). In aerospace, this radar is used to detect enemy aircraft. There is only one object like an aircraft in the sky. It is possible to accurately identify the object based on the signals that hit it and return. We tried to identify what is in the layers thereby sending these signals."

"We sent 200 MHz signals to detect the traces of workers in the tunnel. When the signals are transmitted, they go into the layers of the earth, and if any obstacles are formed, the rays come back. We map where the target object is based on the collision of the incoming rays. There are parts of the drilling machine in the ruins of the tunnel. The returned signals also imply that they hit them," he added.

Dr M Satyanarayana said they have also tried to locate the exact spot of the tunnel collapse from the top of the hill. "We were able to see up to a depth of 200 meters. There is a tunnel 500 meters deep from the hill. If the government asks for further study, we are ready to do it," said Satyanarayana.