Landfilling as a waste management option has potential to pollute all
the three main natural factors of the environment which are land/soils,
air, and waters. In scientific terms these are lithosphere, atmosphere,
and hydrosphere, respectively (Butt et al., 2011). Unlike landfill gas
and (more or less) degraded landfill waste, by virtue of its nature, land-
fill leachate specifically can pollute all of the three aforesaid principal
factors. For instance, leachate vapours or fumes can find their way into
the ambient atmosphere in sufficient amounts to present danger to
human health and the environment, whereas these vapours or fumes
can be containing chemical and/or biological hazards, volatile organics,
etc. Moreover, landfill gas also breaks through from landfill leachate.
Leachate can be an extremely powerful pollutant of water both above
and below ground level – hydrosphere and hydrogeosphere. In addition,
leachate contaminants can pollute land/soils as it moves through
the ground either mixed with water or on its own (e.g. through the
unsaturated zone under a landfill). Therefore, in general, landfill
leachate can be seen as a lot more hazardous product of a given land-
fill than the other two – landfill gas and (more or less degraded)
landfill waste.