Efforts to rescue eight people trapped in a collapsed section of a tunnel in Telangana’s Nagarkurnool district entered day four on Tuesday, with experts temporarily halting intensive excavation due to an increase in the amount of slush and mud at the accident site.

Teams of experts that had gone into the tunnel yesterday have said the slush wall has now increased by about a metre. More mud and slush are coming towards the tunnel inlet and the locomotive access has been reduced to about 11.5 kilometres.

Other strategies being discussed now include approaching sideways.

They believe that there could be structural stability issues if intensive excavation is undertaken, which could not only further endanger the trapped workers but also risk the lives of the rescue teams.

Chris Cooper, an Australian tunnel expert part of L&T, on Monday also said the entire area appears unsettled and that it might be too dangerous to continue with heavy-duty digging.

About 3,200 litres of water is also flooding the tunnel every minute, mixing with the vast quantities of sand, rock, and debris to make more mud and slush. It, however, is not a cause of concern as the tunnel is being de-watered.

The rescuers have so far not been able to make any contact with the eight trapped men, who got stuck after a part of the Srisailam Left Bank Canal (SLBC) tunnel collapsed on Saturday morning. Among them are two engineers, two operators and four labourers.

They have been identified as Sandeep Sahu, Jegta Xess, Santosh Sahu and Anuj Sahu, all from Jharkhand, Manoj Kumar and Sri Niwas from Uttar Pradesh, Sunny Singh from Jammu and Kashmir, and Gurpreet Singh from Punjab.

Bleak Chance Of Survival

Telangana Minister Jupally Krishna Rao on Monday said the chances of the survival of eight trapped men were “very, very remote”.

“Muck has piled up too high inside the tunnel which has made it impossible to walk. The rescuers are using rubber tubes and wooden planks to navigate. The chances of survival are very, very remote, but we are hopeful and not sparing any effort,” Mr Rao, who oversaw the rescue operations along with Irrigation Minister Uttam Kumar Reddy, said.

He also said that a team of rat miners, who had rescued the construction workers trapped in the Silkyara Bend-Barkot tunnel in Uttarakhand in 2023, has joined the rescue teams to extricate the trapped men.

Nine national agencies are already engaged in the rescue operation and Chief Minister Revanth Reddy is taking hourly updates.

Experts from the Geological Survey of India and the National Geographical Research Institute have also been roped in to assess the situation.