Classic Article:
Timescale for Completion. (Originally published in the Surveyor Magazine in 1993)
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"Isn't it time your generation stopped leaving all your mess around, for us to clean up?"
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Composting reduces the quantity of waste sent to landfill. But just how long does waste lie around for after it goes into a landfill?.
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Yes, many would say that we are - "leaving our mess around for the generations of the future to clean-up".
Background: This is an article which we wrote over ten years ago which discusses the long time periods of centuries which will be needed before modern landfill sites will become harmless. It includes a "disturbingly simple" calculation to prove this point. Despite the age of the article, and changes in the responsible bodies and regulations - it remains relevant.
Here are some extracts from the article. The full download is available at the bottom of this page:-
"It is now widely accepted among landfill scientists that the timescales involved in the complex degradation of domestic wastes in a typical, large high-density modern landfill site are likely to be centuries rather than decades."
In view of the extensive efforts which have gone into landfill gas research during the last decade, it must be of concern how little has been learned in the fundamental area of timescales which are involved. Graphs which continue to be presented for landfill gas production rates over time remind one of Ann Elk's theory about the brontosaurus, as expounded in Monty Python's Flying Circus: 'All brontosauruses are thin at one end, much thicker in the middle, and then thin again at the far end'.
A disturbingly simple calculation (in the downloaded article) places in context the timescales that are inevitably involved for completion of a typical modern landfill site in terms of production of a contaminated leachate.
It is common knowledge that newspapers can be exhumed from landfills which are over 30 years old, yet remain perfectly legible, indicating that biological decomposition has barely begun. Such items are excavated from landfills which were operating to standards prevailing during the 1950s and 1960s. The process of landfilling then was very different from the massive, high input, high density, deep, engineered deposits of today. At a modern landfill decomposition is expected to take even longer to complete (return to normal use in a condition free from risk to the environment)."
"Realisation and acceptance that many landfills being operated to high standards today, and in complete accordance with guidelines, will not be able to achieve certificates of completion for periods measuring in centuries, may come as a shock to operators and regulators alike."
So the less that goes to landfill and be "left lying around", the better! Carry on composting!
Download the full classic article below:
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