The removal of trace organic compounds through membrane bioreactors (MBR) in comparison to a conventional wastewater treatment plant (WWTP) in a long term study was investigated. Two MBR pilot plants were operated in parallel to a full-scale WWTP, fed with the same municipal raw waste water. Bulk organic parameters such as COD and TOC, high polar compounds (phenazone-type pharmaceuticals, their metabolites and carbamazepine), and less polar estrogenic steroids (estradiol, estrone and ethinylestradiol) were quantified. The removal rate of phenazone, propyphenazone and formylaminoantipyrine by the conventional WWTP was below 15 %. Significant higher removal rates (60-70 %) started to be clearly monitored with the pilot plants after about 5 months. The removal of the drug metabolite acetylaminoantipyrine during conventional treatment was below 30 % and reached 70 % in both pilot plant. Higher removal rates coincided here with higher temperatures at the summer time. Carbamazepine was not removed during conventional and membrane activated sludge treatment.The conventional WWTP removed in average more than 90 % of the natural steroids estrone and estradiol and about 80 % of the synthetic ethinylestradiol. The elimination of estradiol and estrone by the MBR processes were of about 99 % and Ethinylestradiol was removed by about 95 %.

The aim of the study was to evaluate the influence of variable redox conditions on a number of pharmaceutically active compounds, namely carbamazepine, phenazone and AMDOPH (1-acetyl-1-methyl-2-dimethyl-oxymoyl2-phenylhydrazide) below an artificial recharge pond in Berlin. The redox conditions change seasonally, mainly as a result of temperature changes of 0 to 24°C in the infiltrate. Aerobic conditions prevail in winter, while manganese reducing conditions are reached below the pond in summer. Phenazone is redox sensitive and was generally fully degraded before reaching the first groundwater well as long as oxygen was present. When conditions turned anaerobic, phenazone was not fully eliminated. AMDOPH (1-acetyl-1-methyl-2-dimethyl-oxymoyl2-phenylhydrazide) and carbamazepine are very persistant drug residues. However, results suggest that AMDOPH may be degradable under certain favourable conditions (i.e. aerobic conditions; relatively high temperatures, low recharge rates), but further studies will need to verify this statement.

The redox conditions below an artificial recharge pond in Berlin were largely dependent on seasonal temperature changes of 0-24 °C in the infiltrate. Aerobic conditions prevailed in winter, when temperatures were low, while anaerobic conditions were reached below the pond when temperatures exceeded 14 °C. In contrast to temperature changes, cyclic changes between saturated or unsaturated conditions below the pond had only a minor effect on the redox conditions. However, the intrusion of gaseous oxygen during unsaturated conditions caused a temporary reinforced increase in oxidation of particulate organic matter. The effect of variable redox conditions on the behaviour of a number of pharmaceutically active compounds, namely carbamazepine, phenazone and several phenazone-type PhACs, was investigated. Phenazone is redox sensitive and was generally fully degraded before reaching the first groundwater well, as long as oxygen was present. When conditions turned anaerobic, phenazone was not fully eliminated. 1-Acetyl-1-methyl-2-dimethyl-oxymoyl-2-phenylhydrazide (AMDOPH) and carbamazepine are very persistent drug residues. However, results suggest that AMDOPH may be slightly degradable under aerobic conditions too, but further studies will be needed to verify this statement.

The spatial distribution of confining layers within a system of two aquifers strongly affects the hydraulics and sensitivity to pollution. The test site is located close to a well field. Wells are switched with short intervals and hydraulic heads are recorded in several observation wells. Because the absolute levels of simulated hydraulic heads do not always coincide with the measurements, the model is calibrated with short term head variations. The characteristic shape of the hydraulic heads at each observation wells contains sensitive information about the structure of the aquifer. A numerical technique is developed which enables to simulate the spatial distribution of the confining layer. The method comprises the use of pilot points and regularisation technique. Cross validation is carried out in order to show the results are physically based. The method is shown to provide significant results even under non optimal conditions.

In den letzten Jahren hat die Untersuchung des Vorkommens und Verhaltens von Arzneistoffen und endokrin wirksamen Substanzen in der Umwelt zunehmend an Bedeutung gewonnen (Daughton and Ternes, 1999; Kümmerer, 2001; Heberer, 2002). Verschiedene Studien zeigten, dass abwasserbürtige Verbindungen zum Teil nicht oder nicht vollständig durch die Behandlung des Abwassers entfernt werden (Heberer, 2002; Ternes, 1998; Daughton and Ternes, 1999). Somit können unter anderem Humanpharmazeutika und deren Metabolite über Kläranlagenabläufe in die aquatische Umwelt gelangen. Da die Wirkschwelle solcher Verbindungen zum Teil schon in sehr geringer Konzentration erreicht wird (z.B. Ethinylestradiol - Purdom et al., 1994) oder die Datenlage hierzu unzureichend ist, gewinnt die Entfernung der Spurenstoffe während der Abwasserbehandlung immer mehr an Bedeutung. Membranbelebungsanlagen könnten hier einen verbesserten Rückhalt bewirken. Neben der biologischen Phosphor- und Stickstoffentfernung (Gnirss et al., 2003; Lesjean et al., 2002) war es Ziel dieses Forschungsprojektes, die Entfernung von ausgewählten organischen Spurenstoffen in zwei Membranbelebungsanlagen im Vergleich zu einem konventionellen Klärwerk zu untersuchen.