Fiction: Bags that go to landfill should degrade, and not last thousands of years.
Fact: No. In a properly engineered landfill, nothing is meant to degrade. Bags of all materials - cotton, paper, plastic and reusables - will not decompose.
- Biodegradables are not an answer either because they can degrade even without oxygen present and create greenhouse gases.
- Countries around the world are restricting the amount of biodegradable material in landfills. Germany has banned bio-waste entirely from landfill.
- The European Union Landfill Policy mandates reductions in bio-degradable waste. The Directive sets demanding targets to reduce the amount of bio-degradable materials sent to landfill in three phases.1
- These targets are:
- By 2010 to reduce biodegradable municipal waste landfilled to 75% of that produced in 1995
- By 2013 to reduce biodegradable municipal waste landfilled to 50% of that produced in 1995
- By 2020 to reduce biodegradable municipal waste landfilled to 35% of that produced in 19952
How Landfills Work
- There is considerable misinformation on how landfills work. Landfills are not bio-reactors, meaning they are not meant to break materials down to nothing so we can continue to refill. They are designed to entomb or mummify waste.
- Landfills are engineered to create low-oxygen environments so that the waste will not decay. They are lined with clay and thick plastic liners to contain fluids and gases created by anerobic decomposition. The waste is compacted and covered with soil daily, and at the end of their life, they are capped to prevent leakage, in or out.3
- Today's modern landfills are composed of four main elements: a bottom liner (which can be made from clay, plastic or a composite material), a leachate collection system, layers of sand and soil, and a cover.
- A garbage study sponsored by the University of Arizona and published in “Rubbish: The Archeology of Garbage (2001) by Dr. William Rathje confirmed the dynamics of landfills as low-oxygen environments that preserve contents. The study of a Phoenix landfill found that "almost all the organic material" from the 1950s "remained readily identifiable: Pages from colouring books were still clearly that, onion parings were onion parings, carrot tops were carrot tops."