Legacy leachate at the Jawahar Nagar land fill facility is proving to be an insurmountable problem for GHMC authorities, and a continuing menace for residents of the surrounding colonies.
Even as the legacy dump with 12 million tonnes of city garbage is being capped, the issue of leachate oozing out of the dump has remained unsolved for years.
Several attempts to get the leachate treated completely have fallen through, and all that the authorities have managed to do is maintain a status quo so far.
On Tuesday, the issue came to the fore again, when the leachate mixed water reportedly from Malkaram lake seeped on to the road causing a spate of accidents.
There is a total of 750 million litres (ML) of leachate stored in several ponds exclusively dug for this purpose in Jawahar Nagar, outside the Solid Waste Management facility.
Two existing plants each with a capacity to treat 2,000 litres per day, strive to maintain the leachate at 600 ML, in the absence of which the quantity would be enhanced by rain water, and result in widespread pollution and crop damage.
Sources from Irrigation department informed that during the heavy downpour in October, all the ponds and Malkaram lake, where leachate was stored, overflowed onto the road. Water was mechanically drained downstream, spreading the pollution to connected lakes at Dammaiguda, Nagaram and Cherlapally.
Repeated attempts have failed towards treatment of the total leachate at once. Global tenders were called twice, but have not yielded result.
“The first time we called for tenders on Build-Operate-Transfer basis, the least bid was for ₹340 crore, which we thought, was excessively quoted. The tenders were cancelled, and called for again just before elections, limiting the brief to complete treatment of existing leachate at a cost of ₹240 crore. There was no response for that,” shared an official.
Efforts are on to call tenders a third time, this time on Build-Operate-Own model. Proposals have been prepared and sent to the GHMC Commissioner, who in turn, will forward the same to the state government for approval.
“As per the proposal, the bidder will have to design the plant, build it, and operate to completely treat the leachate, existing and even that which might ooze in future. He may take up work from outside too based on completion of our quantity. Government will bear the complete cost, ₹270 crore, and seek 20% share from the earnings accrued to the agency from outside work,” explained the official.
The procedure involves repeated cycles of treatment till the leachate is reduced to a sludge, which would then be sun dried into a powder form, and disposed of to the landfill.
