A lined pit that runs out of air
Where Does Rubbish Actually Go?
A landfill is a sealed lined pit, and things rot far more slowly inside it because so little oxygen gets in.
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Step 1 of 5
It is not a hole in the ground.
A modern landfill is dug, then lined with clay and thick plastic, so that rain trickling through cannot carry anything into the water below.
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Step 2 of 5
Covering it each day starves it of air.
Sealing every layer keeps smells and birds away, but it also keeps oxygen out — and rotting needs oxygen. So the rotting nearly stops.
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Step 3 of 5
What rots down there makes methane.
The microbes that manage without oxygen give off methane instead of carbon dioxide. It is a far stronger greenhouse gas, so it is piped out and burned.
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Step 4 of 5
Newspapers come out still readable.
Digs into old landfills routinely turn up decades-old newspapers you can still read, and food scraps that have barely changed. Nothing had the air to eat them.
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Step 5 of 5
The best thing is for less to arrive.
A landfill is a store, not a solution — everything put in is still there. Recycling, repairing and composting all work by keeping things out of it.
Landfill gas is roughly half methane, and burning it generates electricity. A large site can power several thousand homes from what its own rubbish gives off.
The short version
A landfill is a lined, sealed pit where rubbish rots extremely slowly for want of oxygen, giving off methane that has to be collected.
Try it yourself
Bury an apple core in a sealed bag of soil and put another in an open pot. After a month the open one is going and the sealed one is not.
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