KMDA starts processing of legacy waste

Kolkata: In a bid to curb pollution, Kolkata Metropolitan Development Authority (KMDA) has started processing of legacy waste by biomining in six municipalities of the state.

Biomining refers to an environment-friendly technique to separate soil and recyclables from legacy waste. Waste which has been kept for years at some barren land or a place dedicated for landfill is known as legacy waste.

The state government has designated KMDA as the nodal agency to execute the National Green Tribunal's directions for removal of legacy waste from 69 dumpsites.

The work has already begun in Siliguri, Kharagpur, Midnapore, Berhampore, Murshidabad and Bolpur. These civic bodies contribute 22 per cent of the total solid waste, which weighs around 8 lakh metric tonne.

"The agency has already started the survey work. It is collecting samples from the waste for checking the characteristics of the same. We hope to start segregation from January," said a senior official of KMDA. The time period for completion of segregation will vary from 1 year to 18 months depending upon the quantity of waste generated in the civic bodies. "The agencies will face penalty if they are unable to execute the work within the stipulated time period," said the official.

The state generates around 62 million tonnes of solid waste annually.

The waste will be put into a trammel machine for segregation into two major components — waste comprising leaves, reusable plastic as Refuse Derived Fuel (RDF) (that can be used in cement factories as an alternative fuel), and inert waste (that can be used as soil conditioner.)

There are 88 dumpsites across the state as reported to NGT. Some of the civic bodies like Kolkata, Bidhannagar, Asansol and Durgapur have individually taken up the task. KMDA has divided 69 dumpsites into 29 clusters.

Groundwork for more than 30 odd civic bodies that comprise municipalities like Panihati, Madhyamgram, Halisahar, Titagarh in North 24 Parganas and Purulia are also expected to begin by December.

Legacy waste forms methane gas, which when comes in contact with oxygen causes fire. The smoke emitting from this waste contains carbon dioxide, carbon monoxide, sulphur oxide and nitrogen oxide.

It is also rich in PM 2.5 and PM 10 — tiny pollutants that enter the deepest crevices of the lungs and can trigger a host of respiratory diseases.