Keep away from water table till waste is sorted

The East Delhi Municipal Corporation has finally been allotted land to set up a garbage processing facility as an alternative to the Ghazipur dumpsite that stands almost as tall as the Qutab Minar and should have stopped receiving Delhi’s trash 17 years ago. But the choice of land has triggered protests.

Ghonda Gujran, where the processing plant is coming up, is in the “O Zone” or the Yamuna riverfront. Environmentalists are concerned about leachate that can contaminate precious aquifers, posing ecological and health hazards.

Clearing the land for the project last year, the Central Pollution Control Board, however, said that it was “1,950 metres away from a water body” and “not a floodplain”. But the local villagers do not want the project in their backyard.

Multiple studies have shown that leachate — a toxic liquid that drains from a landfill — generated from waste dumpsite contaminates the groundwater. In a 2017 report, scientists from Jamia Millia Islamia said markets around the Ghazipur landfill should be relocated and homes be provided piped water supply. Groundwater should be used for potable purposes only after appropriate treatment.

The EDMC insists that its integrated waste management facility is not a landfill but a bunch of “scientifically managed” units. The waste-to-energy (WTE) plant will process combustible waste to generate energy and the ash left behind will be used to make bricks. The bio-methanation unit will process wet waste to make methane and manure. The construction debris will be processed separately, and the aerobic composter will make compost. All these will ensure no stench and “almost zero” residue, said an official, who is associated with the project.

Delhi’s existing waste processing plants, however, leave behind large quantities of pre-processing rejects and post-processing residue. They just pile up at the site. Take the Ghazipur WTE, for example. An EDMC official said that the plant, which has a treatment capacity of 1,500-1,300 tonnes treats an average of 700 tonnes of garbage every day and rejects 800 tonnes of trash, mostly biodegradables, inerts and ash from combustion.

To dispose of the rejects and residue at the proposed waste management facility, the official said, the corporation may require a landfill, possibly at another site. “Its location, size, and how scientifically it’ll be engineered to prevent leachate is crucial,” said an expert, requesting anonymity. Any landfill at Ghonda Gurjan would have to take into account the high groundwater table, the expert warned.

Segregation is the key to waste management. Almost half of Delhi’s solid waste consists of compostable matter but proper sorting of the wet waste is a must for generating quality compost. If waste sorting is efficient, landfills can become redundant.

The Management of Solid Waste (MSW) Rules, which Delhi notified in January last year, ask generators to segregate wet waste, dry waste and domestic hazardous waste at source before handing over to the waste-pickers. The local bodies have to register and pay waste-pickers and waste-dealers for the thankless job they do, and set aside space for material recovery and storage facilities locally.

In an ideal situation, when these rules are enforced and the work-chain is maintained, the cleaned up wet waste would go to local composting and bio-methanation plants, the recyclables to recycling units, and only material such as multi-layered packaging, low-quality plastic bags or any polymer that cannot be recycled infinitely, to the WTE plant.

But one year since the adoption of the MSW rules, the city’s segregation efforts have been restricted to pilot projects, which are running in fits-and-starts. The fines for people who do not segregate have not been imposed and decentralised sorting stations, which were to come up in existing dhalaos (community dump yards), have not started functioning in most locations. “Collect and transport it to a central processing plant is still the preferred model,” said Swati Sambyal from the Centre for Science and Environment.

At a more fundamental level, both the city administration and the citizenry must consider the primary question: Wouldn’t we have less cleaning to do if there was less garbage? The idea of reduce, reuse and recycle is no longer an environmental fad. This is a real solution, perhaps the only solution that can prevent our city from sinking under its own garbage.

First Published: Apr 01, 2019 03:06 IST