DISTRIBUTION OF CONTAMINANTS AND THE SELF-PURIFYING POTENTIAL FOR AROMATIC-COMPOUNDS IN A CARBONIZATION WASTE-WATER DEPOSIT

The Schwelvollert, a highly colored carbonization wastewater deposit l ocated in Saxony-Anhalt (eastern Germany) was the subject of extensive analytical studies. When sampled in autumn the pyrolysis effluent lak e was found to be stratified in three distinct layers, each exhibiting different physicochemical and microbiological characteristics. Althou gh no oxygen was detectable in the whole deposit, aerobic bacteria wer e shown to predominate among pollutant degraders: in the upper layers about 40-60% degraders of phenolic compounds in heterotrophic microbia l communities were found. Neither nitrate-reducers nor sulfate-reducin g or methanogenic consortia that degraded benzoate were detectable. Ho wever, nitrite-reducing benzoate degraders were found with MPNs rangin g from 0.03 to 20/mL. The attempt to identify aerobic isolates from th e top layer with the commercially available BIOLOG and API 20NE identi fication systems revealed their unsuitability for the determination of specific pyrolysis effluent bacteria. Although the aerobic bacteria w ith specific degradation abilities are not likely to use their abiliti es under in-situ conditions, they represent a degradation potential wh ich might be useful for aerobic remediation strategies. (C) 1997 Elsev ier Science Ltd.