Abstract
The major potential environmental impacts related to landfill leachate are pollution of
groundwater and surface waters. Landfill leachate contains pollutants that can be categorized into
four groups (dissolved organic matter, inorganic macrocomponents, heavy metals, and xenobiotic
organic compounds). Existing data show high leachate concentrations of all components in the early
acid phase due to strong decomposition and leaching. In the long methanogenic phase a more stable
leachate, with lower concentrations and a low BOD/COD-ratio, is observed. Generally, very low
concentrations of heavy metals are observed. In contrast, the concentration of ammonia does not
decrease, and often constitutes a major long-term pollutant in leachate. A broad range of xenobiotic
organic compounds is observed in landfill leachate. The long-term behavior of landfills with respect
to changes in oxidation-reduction status is discussed based on theory and model simulations. It seems
that the somewhere postulated enhanced release of accumulated heavy metals would not take place
within the time frames of thousands of years. This is supported by a few laboratory investigations.
The existing data and model evaluations indicate that the xenobiotic organic compounds in most
cases do not constitute a major long-term problem. This may suggest that ammonia will be of most
concern in the long run.
Original language | English |
---|---|
Journal | Critical Reviews in Environmental Science and Technology |
Volume | 32 |
Issue number | 4 |
Pages (from-to) | 297-336 |
ISSN | 1064-3389 |
DOIs | |
Publication status | Published - 2002 |
Keywords
- dissolved organic matter
- toxicological testing
- ammonia
- waste disposal
- heavy metals
- xenobiotic organic compound