The State Level Monitoring Committee (SLMC) on Solid Waste Management has asked the Kochi Corporation to adopt the Indore Model for treatment of legacy waste lying at the civic body’s dump site at Brahmapuram for long.
Indore Model refers to the award-winning initiative by which city administrators cleared legacy waste that had piled up at the 100-acre dump site at Devguradia in the city. Over 15 lakh metric tonnes of legacy waste had piled up at the site over decades.
Municipal administrators implemented bio-mining and bio-remediation to treat legacy waste.
Recyclable materials were sent for recycling, while recyclable polythene was sent to cement plants for use in the construction of roads. Construction and demolition waste was sent to a special facility set up for scientific collection and disposal.
Trommel machines were used to manage waste in accordance with Central Pollution Control Board (CPCB) norms. The process, which took almost three years, was carried out with the cooperation of various allied agencies.
The Indore Model of treating legacy waste using bio-mining and bio-remediation had won praise from the National Green Tribunal (NGT). It had then pointed out that the model was in line with solid waste management rules and CPCB guidelines on treatment of legacy waste.
The first step is to excavate legacy waste, loosen it and make windrows, so that leachate can be dried through solar exposure, while the entrapped methane gets removed from the heap.
All biodegradable waste, including discarded food, fruits, and garden waste, need air to decompose in an odourless way without producing leachate.
The addition of composting biocultures speeds up decomposition and rapidly creates biological heat within the waste that helps in drying it out and reducing the volume by 35% to 40%. This happens through loss of moisture and decomposition of aerated waste to carbon dioxide and water vapour, according to CPCB guidelines.
The State Pollution Control Board had proposed drone mapping of solid waste at Brahmapuram. The total station survey using drones was planned to ascertain the exact volume of waste at the site. The board had suggested a precursor study of the history of the site and compositional analysis of waste.
Site environment parameters such as baseline study of heavy metals in surface and subsurface soil and water, rainfall, soil type, surface hydrology, topography, and wind direction should be done before and after biomining, according to the board.
