NHPC workers killed in Sikkim tunnel methane explosion

The National Green Tribunal (NGT) has initiated proceedings following the deaths of at least 25 workers during a suspected methane gas release at the Teesta VI Hydroelectric Project in Sikkim’s Namchi district. The incident occurred on July 20 inside a head-race tunnel under construction by the National Hydroelectric Power Corporation (NHPC). The explosion, caused by a sudden burst of suspected methane gas trapped in rocks, produced dense fumes and toxic gases, leading to a rockfall that trapped workers.

Internal NHPC documents indicate the company had been aware of methane risks at the site since at least January, when a leakage caused burn injuries to workers. Despite this, documents suggest the company lacked adequate infrastructure to manage methane in July. Tenders for methane monitoring, ventilation, and gas detection equipment were only floated in June and July, shortly before the fatal incident.

The NGT has directed the Namchi district administration, the Central Pollution Control Board, and the Sikkim Pollution Control Board to file responses regarding the circumstances of the deaths. The tribunal is also investigating potential environmental violations, including illegal tree felling in forest areas. The case has been transferred to the NGT’s Eastern Zonal Bench in Kolkata for a hearing on September 3.