Why do landfills catch fire during summers?

Source: The post is based on the article “Why do landfills catch fire during summers?” published in The Hindu on 15^th March 2023.

Syllabus: GS 3 – Environmental pollution and degradation

Relevance: measures needed to prevent landfill fires

News: The Kochi landfill site caught fire earlier this month. This reminds the Indian cities to be prepared for such incidents in upcoming summer months.

What are the reasons behind the landfill fire?

India’s municipalities collect more than 95% of the waste generated in cities but the efficiency of waste-processing is 30-40%. Therefore, unprocessed waste remains in open landfills for long periods of time.

This openly disposed waste includes flammable material like low-quality plastics, rags and clothes.

Further, the biodegradable fraction composts much faster in summers. This in turn increases the temperature of the disposed wastes beyond 70-80°C. This high temperature along with flammable material makes fire possible in the landfill.

Read More: Dump This Practice – Kochi garbage fire is a warning to all cities

What can be done to prevent landfill fires?

First, the disposed material can be completely capped, and landfills be closed in a scientific manner. 

However, this solution is not suitable for India because the land can’t be used again for other purposes and there are also specific operating procedures for the closed landfills.

Second, bioremediation techniques can be adopted to clear the piles of waste. Automated sieving machines can be used to segregate the flammable refuse-derived fuel (RDF) (plastics, rags, clothes, etc.) from biodegradable material.

The RDF can be sent to cement kilns as fuel while the bio-soil can be distributed to farmers to enrich soil.

However, implementing a bioremediation project usually takes up to two or three years. Therefore, there is a need for short-term solutions for landfill fires.

What are the short-term solutions available for landfill fire?

The landfill site can be divided into blocks depending on the nature of the waste.

Blocks with fresh waste should be separated from blocks with flammable material at each landfill site. The blocks can be separated using a drain or soil bund and a layer of soil should cap each block.

The most vulnerable part of the landfill which contains lots of plastics and cloth should be completely capped with soil.

After the division of the landfill into blocks, the landfill operator should classify incoming waste and dispose of it in designated blocks rather than mixing it.

Non-recyclable and non-biodegradable segregated wastes should be sent to cement kilns instead of accumulating them. Dry grass material and dry trees from the site should also be cleared immediately.

These are some short-term measures that can be adopted. However, a permanent and long-term solution is needed.

What can be the long-term solution? 

The long-term solution can be adopted by ensuring cities have a systematic waste-processing system where wet and dry waste are processed separately and their byproducts treated accordingly.