CHENNAI: The mercury level in water bodies around Neyveli Lignite Corporation (NLC) in Cuddalore is 115 times the safe threshold, stated a report submitted by the Tamil Nadu Pollution Control Board (TNPCB) to the southern bench of the National Green Tribunal (NGT).

As per the report, as many as 17 samples were collected from surface water sources for the analysis. "The parameter mercury is present in 15 out of the 17 sources of surface water collected in the range of 0.0012 mg/L to 0.115 mg/L," it said.

As per Surface Water Standard IS 2296 CLASS E, there is no upper limit set for mercury in surface water that is classified unfit for drinking or irrigation purpose, there is a standard for its concentration in groundwater, which is 0.001 mg/L.

Meanwhile, six samples of ground water showed the presence of mercury ranging from 0.0025 mg/L to 0.0626 mg/L.

Since the NGT is hearing a suo motu case pertaining to severe pollution around the NLC mines, a directive was issued to the TNPCB to analyse and submit a report on the water samples from the area.

Poovulagin Nanbargal, an environmental organisation that studied the pollution around the mines, said Buckingham Canal had 115 times higher mercury content and the groundwater had 62 times higher concentration. "If mercury does not form naturally in water bodies, what is the source of the heavy metal here? Won’t the cattle that drink water from those water bodies and the fish in them be affected?" the organisation asked.

The organisation added that groundwater samples collected from Vanathirayapuram had 62 times higher mercury content. "The residents of the locality have been using the groundwater for drinking purposes for a long time. The government should form a special medical team to check the health condition of the residents," the organisation urged.