Humans have a few basic methods to dispose of waste, burn it, bury it, or dump it at sea (no longer an option). Each of the disposal routes has environmental implications, transporting waste to the incinerator or landfill requires fuel with the associated air pollution emissions.

Both landfill and incinerator require materials and energy for construction and their impacts on air, land and water are fairly well publicised.

Figure 2 shows the basic construction of a landfill. This example is full and has been "capped".

The materials in the site are in the process of degrading, but this may take many hundreds of years and the liquids and gases produced may leak from the site and affect the local area.

• Toxic materials can find their way into the local groundwater.
• Whilst any methane produced can also pose a hazard if it leaks into houses causing explosions. (Loscoe, 1976) methane is also a greenhouse gas. So with landfill there is a continuing problem long after the site has been useful it requires monitoring.

Incineration as a waste disposal technique has become more controversial in recent years. This is partly due to reports of the various pollutants that can be emitted, the most publicised of these are compounds known as Dioxins and Furans which are thought to cause birth defects and cancer. However these materials are considered to be produced in minuscule amounts in well-regulated plants, below levels at which they might have health implications. In addition incineration can be used to provide energy and plants that produce energy from waste for local cities can be seen as a beneficial method of dealing with waste.