A report submitted by the Tamil Nadu Pollution Control Board (TNPCB) before the southern bench of the National Green Tribunal (NGT) shows that the Greater Chennai Corporation’s (GCC) waste incinerator in Manali has been storing incinerator bottom ash with dangerously high levels of heavy metals such as cadmium, chromium, and lead. 

Laboratory tests showed that cadmium levels were found to range between 291.6 and 364.5 mg/kg, compared to the safe limit of 1.0 mg/kg, indicating an exceedance of around 364 times. Lead levels were also extremely high, ranging from 349.2 to 436.5 mg/kg, about 87 times the acceptable standard. 

The plant, which incinerates up to 10 tonnes of non-biodegradable waste every day,  was initially issued consent in 2019 by the TNPCB.

However, during an  inspection on April 2, 2025, TNPCB officials found the incinerator inactive but traces of recent activity, including hot ash, suggested ongoing operations. The facility’s air pollution control systems, specifically the venturi and wet scrubbers, were found in a dilapidated state, rendering them ineffective in filtering out harmful emissions. The TNPCB also found that incinerator ash was stored on open ground. This toxic ash was reportedly being sent to the Kodungaiyur dump yard for further processing. In light of these violations, the TNPCB ordered the GCC to cease operations on April 2, until the plant applies for renewal of consent to operate.

A follow-up inspection on April 7, 2025, confirmed the plant remained inactive. However, the TNPCB did not get a response from the GCC regarding the renewal application.