Ageing Effects of Highmolecular Weight Organic Acids Which can be Isolated from Landfill Leachates

The huge number of landfills and the resulting seepage water leads to a negative influence on the ground water quality. Organic acids were isolated over a period of three years from anaerobic and aerobic leachate water and from model aquifers which were fed by the leachates. The amount of isolated DOC increased from the anaerobic samples to the aerobic ones. The characterization of the isolated acids clearly reflects an increase of the molecular weight and of the functional group content with increasing age of the landfill, and in the process of aerobic digestion. The results are not only of interest for a detailed understanding of the fate of organic material from landfill leachates and of the transport of pollutants in the groundwater, but represent a man-made influence on the genesis of humic substances.