LANDFILLS

1. Context

2. What is a Landfill?

• A landfill site, also known as a rubbish dump, garbage dump, or dumping ground, is a site for the disposal of waste material. It is the oldest and most common form of waste disposal.
• US Environment Protection Agency (EPA) has established specific guidelines regarding the creation and management of Landfills.
• In India, landfills are managed under the new solid waste management rules (SWM), 2016.
• However, many of the guidelines have not been adhered to e.g., the Bhalswa landfill is right next to the Bhalswa lake. However, the SWM Rules 2016 mandate that the landfill site shall be 100 metres away from a river, 200 metres from a pond, 500 metres away from highways, habitations, public parks and water supply wells and 20 km away from airports/airbases.

Image Source: Blackstone Environment

3. How do landfills catch fire?

• India's municipalities have been collecting more than 95% of the waste generated in cities but the efficiency of waste processing is 30-40% at best.
• The municipal solid waste consists of about 60% biodegradable material, 25% non-biodegradable material and 15% inert materials, like slit and stone.
• Municipalities are expected to process the wet and dry waste separately and to have the recovered byproducts recycled.
• Unfortunately, the rate of processing in India's cities is far lower than the rate of waste generation, so unprocessed waste remains in open landfills for long periods of time.
• This openly disposed of waste includes flammable material like low-quality plastics, which have a relatively higher calorific value of about 2,500-3,000 kcal/kg, and rags and clothes.
• In summer, the biodegradable fraction composts much faster, increasing the temperature of the heap beyond 70-80 degrees celsius.
• A higher temperature coupled with flammable materials is the perfect situation for a landfill to catch fire. Some fires go on for months.

4. Reasons behind frequent landfill fires

• Landfills are the largest source of methane emissions which are highly flammable in nature and play a large role in the ignition of landfill fires. 
• The decomposition of waste is largely anaerobic in a landfill, which results in the production of large quantities of methane and carbon dioxide.
• The surface fires at dumpsites are also caused by equipment-related factors. This includes debris trapped under machines, heat from equipment (exhaust pipes) and welding.
• These fires are also a result of human factors. Waste pickers who scavenge the waste may inadvertently start a fire by smoking in the landfill.
• The temperature of a region also aids in fire generation. For instance, the ongoing heat wave in Delhi enhanced the probability of fire in a landfill.

5. Impacts of Landfill fires

• Fore at the Bhalswa landfill site churned out dense plumes of smoke and turned the sky hazy grey leading to air pollution. Further, there is a release of a large amount of GHG gases.
• It causes health ailments in residents living nearby the landfill like sore throat, itchy eyes and breathing problems.
• A thick layer of smoke caused by fire impairs the visibility of commuters. For instance, vehicles travelling on the Pallavaram-Thoraipakkam 200 feet radial road (near the perungudi dump yard) have been experiencing poor visibility since the onset of the fire.
• It also impacts the nearby schools in the vicinity which are forced to shut down temporarily in wake of children's health.

6. Solutions to manage landfill fires

• There are two possible permanent solutions to manage landfill fires.
• The first solution is to completely cap the material using soil, and close landfills in a scientific manner. This solution is unsuitable in the Indian context, as the land can't be used again for other purposes. Closed landfills have specific standard operating procedures, including managing methane emissions.
• The second solution is to clear the piles of waste through bioremediation excavate old waste and use automated sieving machines to segregate the flammable refuse-derived fuel (RDF) (plastics, rags, clothes, etc.) from biodegradable material.
• The recovered RDF can be sent to cement kilns as fuel, while the soil can be distributed to farmers to enrich the soil. The inert fraction will have to be landfilled. However, implementing a bioremediation project usually takes up to two or three years, necessitating a short-term solution for summertime landfill fires.

7. Government initiatives to control landfill fires