A methane burst at the Teesta Stage-VI hydroelectric tunnel site in Sikkim’s Namchi district has killed at least 15 workers, while rescue operations continue. The incident has renewed attention on underground construction safety in the fragile Himalayan belt and on whether environmental and technical safeguards were adequate.
What happened
The site team struck a suspected trapped pocket of methane at the tunnel site. The burst partially damaged the tunnel and caused casualties among an estimated 25 workers at the site.
Why methane matters in tunnelling
Methane is a known hazard in underground excavation. In fractured rock and weak geological formations, gas pockets can remain hidden until excavation opens them. Once released, methane can create an explosion risk and can also make rescue work more dangerous.
Background and earlier position
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