IRON AND MANGANESE SURVEY IN AQUIFERS SURROUNDING LANDFILLS IN WALLONIA (BELGIUM)
The groundwater biogeochemistry around waste disposal facilities has been widely studied since twenty years (Christensen & al, 2001). It is well known that leachates produced by water percolation through waste solid often contain high concentrations of dissolved Fe and Mn (Christensen & al, 1997). Fe(III) and Mn(IV) also enter in the composition of aquifers matrix (silts, sand, rocks). It constitutes a second reserve of electrons acceptors for further anaerobic biodegradation in aquifer environment.
Fe(II) and Mn(II) are first importance markers for characterizing and surveying aquifers contaminated with landfill leachates. However, they are not included in lists of required parameters imposed by Belgian or international environmental policiesn probably because they are not hazardous. In this study, aquifers under 4 municipal solid waste (MSW) landfills have been sampled using existing monitoring wells. It covers four different types of aquifers. For each of them, sharp increases of Fe(II) and Mn(II) concentrations are observed in some of the wells downgradient from the sites. Regional mean and maximal values for corresponding aquifers can be strongly exceeded without detecting significant anomalies of other markers.
| Copyright: | © IWWG International Waste Working Group | |
| Quelle: | Workshop G (Oktober 2007) | |
| Seiten: | 10 | |
| Preis inkl. MwSt.: | € 10,00 | |
| Autor: | Vincent Lebrun  Ali Kheffi C. Collart Jean-Claude Maquinay | |
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© IWWG International Waste Working Group (10/2007)
The investigation of pollutant transfer from waste or soil with leachate into groundwater is of fundamental importance for the assessment of risk potential posed by abandoned waste deposits or other contaminated sites. Following the German Federal Soil Protection and Contaminated Sites Ordinance (BBodSchV, 1999), a leachate forecast is required for the soil-groundwater pathway. The estimation of the pollutant transfer can be performed, among other methods, on the basis of source term strength of contaminated materials determination by laboratory tests.
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© IWWG International Waste Working Group (10/2007)
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© IWWG International Waste Working Group (10/2007)
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