In South East Asia, as is the case throughout much of the world, significant tonnages of biodegradable waste are sent to landfill.
Landfills can have devastating effects upon the environment:
Methane gas emission
One tonne of biodegradable waste produces between 200 and 400 cubic metres of landfill gas which comprises approximately 50-55% methane and 40-45% carbon dioxide (CO2).
Methane is 21 times more toxic than CO2 and other greenhouse gases and its emission has significant climate change implications.
Methane gas is flammable and explosive if exposed to heat.
According to the US Environmental Protection Agency (EPA), a significant proportion of the emissions shown to have contributed to global warming and climate change can be traced to landfills, and the disposal of food waste.
No liner can keep all liquids out of the ground for all time. Eventually the liners will either tear or crack and will allow liquids to migrate out of the unit.
US Environmental Protection Agency (EPA)
A concoction of organic and inorganic pollutants (leachate) is produced during landfill site operation and can leak from the landfill contaminating nearby soil and groundwater.
Leachate can include toluene, phenols, benzene, ammonia, dioxins, polychlorinated biphenyls, chlorinated pesticides, heavy metals, and endocrine-disrupting chemicals.
Although many landfills are fitted with pipes and liners designed to route and contain leachate, according to the EPA, no system offers full, indefinite protection.
Consequences of leaks
The extent to which toxic landfill contaminants surpress the imune system has been underestimated.
Dr David O Carpenter, Director of the Institute for Health and the ENvironment at the State University of New York and Albany.
A landfill leak allows toxins to escape directly into the environment, often leading to soil, water, and air contamination. Studies have shown that various health risks are associated with living in the proximity of a landfill, including:
Certain types of cancer, more specifically linked to the bladder and brain, as well as leukaemia.
Researchers at the London School of Hygiene and Tropical Medicine found that babies born to mothers living near landfills had a greater risk of birth defects.
Living near a landfill site has also been shown to expose residents to chemicals that reduce the efficient functioning of the immune system, leading to greater risk of infection.
There is evidence that children living near to waste sites, whether landfills or contaminated bodies of water, are hospitalized more frequently with acute respiratory infections.
The future of landfill
Although many governments have passed legislation to try to reduce reliance on landfill for waste disposal, it is still the most cost effective method, and is therefore likely to remain the most prevalent waste disposal process.
Since landfill sites will continue to generate landfill gas for many years, there is a tremendous opportunity to stabilise and regulate these sites to optimise the production of biofuels and minimise the adverse impact on the environment.
Using landfill gas involves citizens, local governments and industry in sustainable community planning. Commitments to cleaner air, reductions in greenhouse gases and renewable energy go hand-in-hand with economic development, improved public welfare and safety.