CHENNAI: After clear-felling trees in January last year, the contaminated soil was exposed to three successive monsoons - the southwest and northeast monsoons of 2020; and the southwest monsoon of 2021.
Shekar Dattatri, noted wildlife and conservation filmmaker who previously directed “Save Our Sholas”, told Express, “Clear-felling of trees in this ecologically fragile area is not only a violation of existing laws, but also absolutely irresponsible. Without the binding action of trees, vast quantity of mercury-contaminated soil will erode into Pambar Shola and be carried down to the plains. This highly toxic mix will not only affect wildlife, but also have serious health consequences for all coming in contact with the water or soil.”
Nityanand Jayaraman had said in the past that the HUL systematically avoided monitoring mercury levels in the runoff from site, though it is legally bound to. The intensity of rainfall can exceed 201 mm (24 hours) – categorised as extremely heavy rainfall by IMD – during monsoon. “It was our contention that even with vegetation, such intense rainfall will result in a volume of contaminated run-off that will overwhelm silt traps and soil conservation measures,” he said.
Also, high velocity winds can be significant in the area considering the location atop a ridge with sheer drip to Periyakulam plains. Soil protection study also refers to such winds as a threat to trees.
Dust pollution
Albert Jayakumar, a resident of St Mary’s road that shares fence with the factory, said since tree-felling was carried out, there has been a problem of dust pollution and onset of health ailments. “Once the trees were removed and excavation started, the top layer of dust blew inside our homes. We complained to all the authorities, but no action was taken,” he said. Mercury has a dangerous effect on the nervous, digestive and immune system, and on lungs, kidneys, and eyes.
TIMELINE
2001: Kodaikanal residents uncover HUL’s mercury waste at a scrapyard in town. TNPCB issues closure order to the unit on March 23
2003: Supreme Court Monitoring Committee (SCMC) constituted
2005: SCMC sets-up Scientific Experts Committee
2007: TNPCB issues in-principle clearance to HUL to carry out preparatory works for remediation of site
2015: CPCB fixes remediation target of 20mg/kg
2017: NGT permits HUL to carry out trial remediation
2018: TNPCB permits upscaling of remediation
2020: TNPCB issues Consent to Establish (CTE) and Consent to Operate (CTO)
Key points
1 Any remediation has to be done strictly as per the Upscaling Plan and the recommendations contained in Soil Conservation Study and Tree Protection Study
2 Soil Conservation Study says: Where trees are located in dense or close spacing, excavation of soil must be completely avoided
3 Tree Protection Study says, “Removal of top soil up to a depth of 30 cm... is quite dangerous for trees as well as other associated vegetation. This needs to be looked carefully for the sustenance of old trees...”