SLBC tunnel tragedy: Questions mount over Jaiprakash Associates’ lapses

The SLBC tunnel collapse killing eight workers, has spotlighted Jaiprakash Associates’ failure to address geological risks flagged in prior surveys. As rescue efforts end, accountability and safety lapses raise concerns about project management

Hyderabad: As rescue operations to locate six missing workers in the SLBC tunnel tragedy were halted, scrutiny over accountability, safety protocols, and project management lapses has intensified, with blame directed at the implementation agency, Jaiprakash Associates.

A senior Irrigation Department official stated that Jaiprakash Associates is responsible for the tragedy and its costs, as stipulated in the project’s terms. The agency failed to address critical geological risks identified in prior seismic surveys, including a 2020 Tunnel Seismic Prediction (TSP) report by Amberg Tech AG, and resumed work despite known hazards.

---

On February 22, 2025, a routine maintenance operation to fix a water leak triggered a collapse when a three-meter section of the SLBC tunnel’s roof caved in at 13.9 kilometers from the entrance. Occurring in a known fault zone, the collapse buried eight workers under silt, rocks, debris, and flooding water.

The official linked to rescue operations noted that the collapse resulted from disregarding geological warnings.

The 2020 TSP report by Amberg Tech AG flagged a fault zone between 13.882 km and 13.914 km. The report identified decreased rock stiffness- indicating weakened structural integrity in the rock mass, jointed or sheared rock mass, suggesting fractured and unstable geological formations. It also indicated water-bearing zones highlighting severe risks of water seepage, which could destabilize the tunnel further.

These findings, part of Amberg Tech’s TSP-303 Plus system for advanced geological forecasting, were meant to ensure safe tunneling by identifying hazards. However, no review of the report was conducted before resuming work, the official revealed.

It remains unclear whether Jaiprakash Associates shared these findings with the Telangana government. A 2020 research paper co-authored by a former GSI official and a Jaiprakash Associates geologist noted that tunneling began without adequate subsurface exploration due to restrictions in the Amrabad Tiger Reserve, relying on preliminary assessments using aerial photos and remote sensing.

The Geological Survey of India (GSI) and National Geophysical Research Institute (NGRI) had also warned of the tunnel’s geological instability. A 2022 TSP survey by Jaiprakash Associates and Amberg Tech reiterated risks of weak rock formations and water leakage in the same fault zone.

Despite these warnings, the official said, Jaiprakash Associates failed to incorporate the findings into a comprehensive action plan before resuming work in early 2025, raising serious questions about project oversight.