1.2.5 Landfilling
Landfilling is the least favorable method for waste disposal from a sustainable perspective. However,
it is evident that waste that cannot be prevented or recycled ends up in the landfill. A properly designed
landfill can safely contain the waste with a liner system and other safeguards to prevent pollution to the
groundwater [31]. Liners may be made of compacted clay or plastic. Liners prevent the filtration of
liquids, or “leachate,” from a landfill. Leachate has the potential to pollute surface or ground water,
which is the source of most drinking water [45]. Drains may be installed at the bottom of a landfill to
collect the leachate before contamination of surrounding water and soil can occur. Leachate recovered
from drains is pumped to wastewater collection points for treatment. Landfills are closely monitored for
their environmental impact by environmental protection agencies [45].
In a landfill, the waste is spread into layers, compacted to reduce the volume, and covered daily with
clay, ash or soil to minimize odor and deter insects and vermin [32, 45].