Why do landfills catch fire and what can we do about them?

GS Paper 3

Syllabus: Disaster Management

Source: TH

Context: The Kochi landfill site around Brahmapuram that caught fire was a stark reminder that Indian cities need to be prepared for more such incidents as summer approaches.

What triggers landfill fires?

• A landfill site is a site for the disposal of waste materials and is the oldest and most common form of waste disposal.
• The landfill sites in India are not scientifically planned. The efficiency of waste processing is only 30-40%, while India’s municipalities are collecting over 95% of the waste generated in cities.
• The wastes are not segregated due to which the landfill sites receive mixed wastes which include organic waste/ignitable material/plastics.
  • Higher temperature + flammable material = a chance for the landfill to catch fire.
• The anaerobic decomposition (breakdown of organic waste in the absence of oxygen) generates methane gas and heat.
• As soon as the methane gas comes in contact with oxygen, the combustible materials at the dumping site catch fire easily.

Challenges:

• The landfill fires take time to exhaust,
• The fires emit greenhouse gases,
• Multiple ignition points,
• Lack of constant water supply and
• The danger involved in climbing the tall mounds of garbage.

Is there a permanent solution?

• Closing landfills in a scientific manner (SoPs including managing the methane emissions). This solution is unsuitable in the Indian context as the land can’t be used again for other purposes.
• Clear the piles of waste through bioremediation, i.e., excavate old waste and use automated sieving machines to segregate the flammable refuse-derived fuel (RDF) from biodegradable material.
  • The recovered RDF (plastics, rags, and clothing) can be used as fuel in cement kilns, and the biosoil can be given to farmers to improve their soil.
  • There will be a need to landfill the harmless portion.

Immediate measures to manage landfill fires:

• Divide a site into blocks depending on the nature of the waste.
• Blocks with fresh waste should be separated from blocks with flammable material.
• Different blocks should be separated using a drain or soil bund and a layer of soil should cap each block → turned regularly for aeration → helps cool the waste heap.
• The most vulnerable part of the landfill should be capped with soil.
• In addition,
  • Sites should be equipped with water tankers with sprinklers
  • The municipality should have a plan of action in advance
  • Waste-processing workers should have response training, etc.

Way ahead:

• The Solid Waste Management Rules 2016 state that only non-recyclable, non-biodegradable and non-combustible waste should go to a sanitary landfill.
• The problem needs to be addressed at two levels – at the level of public policy (domain of the government), and of the public itself (reducing waste generation/disposal, segregating waste).

Insta Links:

Solid-Waste Management

Mains Links:

What are the impediments in disposing of the huge quantities of discarded solid waste which are continuously being generated? How do we safely remove the toxic wastes that have been accumulating in our habitable environment? (UPSC 2018)

Prelims Links: (UPSC 2019)