PANAJI
Amid repeated concerns raised by locals over water contamination, a study by Goa State Pollution Control Board (GSPCB) as well as National Environmental Engineering Research Institute (NEERI) has revealed a decreasing trend in groundwater contamination in Cuncolim area.
The report, which was placed before the Assurance Committee of the Goa Legislative Assembly, analysed 365 groundwater samples collected between January 2023 and December 2024 from the Cuncolim Industrial Estate and has revealed a decreasing trend in heavy metal contamination.
The findings show that manganese levels exceeded permissible limits in 38% of samples, followed by iron (11%), nickel (9%), lead (4%), cadmium (3%), copper and mercury (1% each), and chromium (0.8%). However, officials noted that the overall trend indicates no additional contamination in recent years.
According to the report, the present concentrations suggest that the metals may be in an immobilised state, having reached saturation levels with no further leaching potential. The study concludes that groundwater quality in the industrial area is not being further impacted by industrial wastewater or related activities.
“All the groundwater samples, irrespective of the industrial estate indicate the presence of Fe & Mn which clearly suggest that the background value is due to the lateritic terrain wherein Fe and Mn leach out owing to tropical climatic conditions,” the study said.
“It is observed from the reports that there is no contamination of heavy metals in ground water in Cuncolim Industrial Estate as only 9% of total samples (365 nos,) analysed indicate presence of Nickel,” it added.
CSIR-NEERI based on the latest study conducted in 2023-24 has reported insignificant concentration in the heavy metals namely -- Cadmium, Manganese, Cobalt, Copper, Nickel and Zinc. “Also, no significant increase in concentrations of any of the heavy metals has been observed in the downstream samples as compared with upstream samples,” it said.
According to NEERI, that also undertook environmental assessment of Captive Secured Landfill Facility (CSLF) of M/s Malco Energy Limited (earlier name M/s Nicomet Industry), the CSLF is safe and secured.
“The report also states that based on the characteristics of the hazardous wastes disposed of in the CSLF, non-occurrence of leachate in the leachate sump and monitoring of groundwater quality across CSLF, NEERI has concluded that CSLF is safe and secured,” it added.
