Judgement of the National Green Tribunal (Eastern Zone Bench, Kolkata) in the matter of Saiful Islam Vs State of West Bengal & Others dated 16/08/2021.

The matter related to the construction of 400/200 KV gas insulated substation in residential area in Bhangar, Block-II, Kolkata, by using hazardous SF6 gas without any Environmental Clearance and storing the same at great risk of leakage which could claim human lives and cause damage to the environment.

The Power Grid Corporation of India Limited in its counter affidavit said that the establishment of 400/200 KV substation has been sanctioned by the Ministry of Power. Further, construction of transmission projects such as overhead high voltage line substation, load centre, switchgears do not attract the provisions of the EIA Notification, July 7, 2004. Further, Environmental Clearance is not required for establishing overhead transmission lines or substations under the Ministry of Environment and Forest Notification, September 14, 2006.

The affidavit filed by the Calcutta Electric Supply Corporation Limited stated that SF6 gas is physiologically completely harmless for humans and animals neither does it deplete the Ozone layer nor does it have any adverse effect when inhaled in the air at a Threshold Limit Value (TLV). The unit in question has installed a gas leakage detector and instrument for measuring dew point.

The Eastern Bench of the NGT, referred to the order of the NGT, Principal Bench, New Delhi (February 21, 2013) - wherein the Tribunal has held that from the  scientific angle, electromagnetic fields are insignificant as the switchgear is duly enclosed in a earthed metallic chamber which eliminates impact of electric magnetic field as per material information provided by WHO document on Health Criteria 238.