A bench headed by Green Court chairperson Justice Swatanter Kumar modified its February 2 order in which it had asked the CPCB and the Delhi Pollution Control Committee to collect the samples every month.
The CPCB contended that keeping in view the expenses involved and the fact that the board did not have any in-house mechanism to analyse toxic chemicals Dioxin and Furans, the sample collection and analysis could be done once in four months.
The bench said, "We allow this prayer. The CPCB is permitted to collect and analyse the samples of ambient air quality once in four months. It shall also conduct at least two surprise inspections and analysis in a year."
The Green Court had earlier allowed the Okhla waste-to-energy plant to function and said it need not be shut down or shifted as it was non-polluting now but directed it to pay an environmental compensation of Rs 25 lakh for its deficient operation in the past.
The Green Court's verdict had come on a petition filed by residents of Sukhdev Vihar alleging that the plant was releasing "toxic" emissions which had affected their health.
The residents had submitted that the plant had obtained an environmental clearance, authorisation and Consent to Operate (CTO) on the condition that it would use Refuse-Derived Fuel (RDF) and bio-gas technology to convert waste to energy. But contrary to its promise, it has allegedly been incinerating mixed waste which has lowered the efficiency of the plant and is causing air pollution.
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