The Central Pollution Control Board (CPCB) has outlined an elaborate process to carry out the remediation works at Edayattuchal and Chakkarachal paddy fields.
The remediation of contaminated soil has to be handled by excavation and off-site disposal in a common hazardous treatment, storage and disposal facility.
The cost for excavation and off-site disposal of contaminated soil at Edayattuchal and Chakkarachal with stabilisation is estimated at ₹12.9 crore. Around 6.9 cubic metres of contaminated soil has to be excavated from all the affected areas (excluding the jarosite pond).
About 20 lakh cubic metres of groundwater has to be treated as per the estimates by the board. It can be done using the pump and treated along with ex-situ treatment with pressure and sand filter or activated carbon filter.
Around 8.5 lakh tonnes of jarosite have been placed in the three ponds, which were not constructed properly to prevent migration of contaminants.
The waste has to be excavated and transferred to the existing pond. This pond has to be capped, besides initiating a long-term operation and monitoring effort.
The estimated cost for remediation of the contaminated sites in Edayar is about ₹47.8 crore.
The CPCB has informed the tribunal that the remediation work may be executed by Edayar Zinc Ltd. under the supervision of the State Pollution Control Board.
The State board could also engage any competent consultant to monitor and verify the works, it said.
