New Delhi: NHPC said late on July 23 that it "deeply mourns the tragic loss of 25 precious lives in this unfortunate incident and extends its heartfelt condolences to the bereaved families," after the rescue operation at the under-construction Head Race Tunnel (HRT) of its Teesta Stage-VI Hydroelectric Project in Sikkim was concluded.
Follow Energy Watch on X
"The rescue operation at the under-construction Head Race Tunnel (HRT) of NHPC's Teesta Stage-VI Hydroelectric Project in Sikkim has been concluded with the recovery of bodies of all the 25 personnel trapped inside the tunnel," the company said.
On support to the families, NHPC said, "The Company stands firmly with the families during this difficult time and is committed to extending all possible support to them."
The conclusion of the operation takes the confirmed death toll to 25, all of the personnel NHPC had said were trapped inside the under-construction tunnel.
Repeating the account it gave earlier, NHPC said the incident occurred on July 20 "after sudden burst of suspected methane gas trapped/embedded inside the rocks which led to explosion generating dense fumes and toxic gases."
The cause has not yet been established. The district administration has said the exact cause is yet to be ascertained. And NHPC itself said that a "detailed investigation will be undertaken to ascertain the cause of the incident."
NHPC listed the agencies it said took part, saying the operation "was carried out with the coordinated support of the District Administration, National Disaster Response Force (NDRF), State Disaster Response Force (SDRF), Ministry of Power, Ministry of Home Affairs, Ministry of Defence, Government of Sikkim, Government of West Bengal, NHPC, Coal India Limited, Patel Engineering Limited, Eastern Coalfields Limited, Western Coalfields Limited, local authorities and several other agencies."
The company said its "Top Management remained present at the project site throughout the rescue operation for closely monitoring and coordinating with all the agencies involved."
NHPC also recorded its thanks to the participating agencies and to "every individual who contributed selflessly to the rescue operation under exceptionally challenging circumstances," and conveyed "special thanks" to the Ministry of Power, the Ministry of Home Affairs, the Ministry of Defence, the government of Sikkim and the government of West Bengal.
The incident took place at 1.04 pm on July 20 at the 500 MW Teesta Stage-VI project at Samardung, in the Jholungey area of South Sikkim. The project is under construction. Patel Engineering Limited, named among the agencies that supported the rescue, is a contractor associated with the works.
Follow Energy Watch on LinkedIN
The Teesta-VI project was among the NHPC assets in the Teesta basin disrupted by the October 2023 flash floods. NHPC's 510 MW Teesta-V station in the same basin returned to full commercial operation on July 16, four days before the incident, after a gap of three years.