Solid waste management in India: legal and technological measures

Introduction

Solid waste is the solid or semi-solid refuse of homes, shops, offices, markets, institutions and streets. Managing it means collecting, segregating, processing and finally disposing of it so that it harms neither people nor the environment. India manages it through a mix of law (who must do what) and technology (how the waste is treated).

The problem of solid waste in India

Indian towns and cities produce growing amounts of mixed garbage as incomes and consumption rise. Much of it has long been dumped outside town limits or burnt to reduce its bulk, and the approach roads of many towns are littered with plastic bags and garbage. Space for dumping is running out in many cities, and dumping and burning are no longer acceptable on either environmental or health grounds.

Legal measures: the Solid Waste Management Rules, 2016

1. Wide coverage. They apply to every urban local body, census town, notified area and industrial township, railways, airports, ports, defence establishments, special economic zones and places of pilgrimage, and to every domestic, institutional and commercial waste generator; industrial, hazardous, bio-medical and e-waste, lead-acid batteries and radioactive waste are left to their own separate rules (rule 2).
2. Waste hierarchy. The Rules set an order of priority: prevention, reduction, reuse, recycling, recovery and disposal, with prevention the most preferred and landfill disposal the least.
3. Duties of every waste generator (rule 4). Each generator must segregate and store waste in three streams, biodegradable, non-biodegradable and domestic hazardous, and hand it to authorised waste pickers or collectors; must wrap used sanitary waste securely and put it with dry waste; must not throw, burn or bury waste on streets, open spaces, drains or water bodies; and must pay the user fee fixed by the local body's bye-laws.
4. Duties of local bodies (rule 15). They must arrange door-to-door collection of segregated waste from every household, slums and informal settlements included, frame bye-laws, fix and collect user fees, recognise and integrate waste pickers, and set up material recovery facilities. Bins for biodegradable waste are to be green, for recyclables white and for other waste black.
5. Processing and disposal. Local bodies must favour decentralised processing, build processing plants and run sanitary landfills only for residual waste.

Technological measures

• Recycling. Paper, plastic, metal, glass and textiles are sorted out at material recovery facilities and passed to waste pickers and recyclers to be remade.
• Biological treatment of wet waste. In composting and vermi-composting, biodegradable waste is broken down by micro-organisms (and, in vermi-composting, by earthworms) into compost that returns nutrients to the soil and can replace chemical fertiliser in parks and gardens. In bio-methanation, organic waste is decomposed by microbes to give a methane-rich biogas that can be used as fuel.
• Sanitary landfill. Unlike an open dump, it is a lined pit where waste is spread, compacted and covered with soil each day; it needs bottom liners and a leachate collection system so that seepage does not reach groundwater, and vents for methane, which is explosive at 5 to 15 per cent in air.
• Incineration and waste to energy. Burning in a designed furnace cuts the bulk of municipal waste by about 90 per cent in volume and 75 per cent in weight, but needs strong air-pollution control because the ash can carry heavy metals. The combustible fraction can also be made into refuse derived fuel or fed to waste-based power plants and cement kilns.

For example, a Delhi resident welfare association that composts its wet waste on site and sends dry waste to a recycler sends almost nothing to the landfill.

Conclusion

The 2016 Rules make segregation at source a legal duty and give local bodies clear tasks, while composting, biogas, recycling and waste-to-energy turn most waste into a resource. Landfill should receive only what is left, as the waste hierarchy requires.