DEGRADABILITY OF ORGANIC-CHEMICALS IN A LANDFILL ENVIRONMENT STUDIED BY IN-SITU AND LABORATORY LEACHATE REACT ORS

The degradability of 19 organic chemicals (BTEX, chlorinated aliphatic compound, nitroaromatic compounds and anilines) in a landfill environ ment was studied using different test systems designed to focus on deg radation and to avoid or account for loss of chemicals by sorption to the waste, by volatilization to the gas phase and/or by leaching. The test systems used were reactors installed in a leachate well at an act ual landfill, reactors submerged in an artificial leachate well in the laboratory and laboratory batch reactors. During the 6-month study pe riod, the different test systems revealed almost identical degradabili ty of the organic chemicals, showing that the less expensive laborator y set-ups were appropriate methods. In the landfill environment studie d, characterized by stabilized anaerobic conditions with law methane p roduction, no degradation was observed for PCE, BTX, naphthalene and a nilines, but 1,1,1-TCA, TeCM, nitrobenzene, 2-methyl-nitrobenzene, 4-m ethyl-nitrobenzene, o-dinitrobenzene and m-dinitrobenzene were transfo rmed. Partial transformation of ethylbenzene (E) was observed. Abiotic processes seemed to be important for the transformation of 1,1,1-TCA, TeCM and partly also for the transformation of the nitroaromatic comp ounds.