Purpose: The transport behavior of human pharmaceuticals in groundwater depends on a multitude of factors such as the physico-chemical conditions in the aquifer and the organic carbon content of the sediment, and, in particular, on the redox conditions in the groundwater. This is of special interest at managed aquifer recharge sites where the occurrence of trace organics is important for drinking water production. The aim of this study was to evaluate the possibility of influencing the redox system of the aquifer in a way that optimizes the potential of managed aquifer recharge systems to reduce the amount of trace organics. Materials and methods: Column studies were performed using natural and thermally treated sediments from an infiltration basin of the Berlin area, Germany. Special emphasis was placed on thermal treatment of the sediments to influence the total organic carbon (TOC) content in the sediment. In one experiment, the sediment was thermally pretreated at 550 °C, in two experiments the sediment was pretreated at 200 °C, and in one the sediment was untreated. Furthermore, the influence of ozonation, a very common disinfectant used in drinking water production, was studied in the experiments. The retardation and degradation parameters for primidone (PMD), carbamazepine (CBZ), and sulfamethoxazole (SMX) under different redox conditions were evaluated. Results and discussion: Oxic conditions were obtained in the experiment with low TOC (0. 06 wt%) in the sediment pre-treated at 550 °C. Anoxic conditions were predominant in two column experiments with a TOC content of 0. 17 wt% in the sediment, irrespective of the mode of treatment (natural or 200 °C). All three pharmaceutical compounds show almost conservative transport behavior with retardation factors between 1. 02 and 1. 25 for PMD, between 1. 06 and 1. 37 for CBZ, and between 1. 00 and 1. 08 for SMX. Differences in the transport behavior were observed depending on the TOC content of the sediment. For CBZ, and to a minor extent for PMD, the higher retardation factors were observed in the sediment with a TOC content of 0. 17 wt% under anoxic conditions. The ozonation of the influent water affects the influent concentrations of PMD, CBZ and SMX. However, it has no influence on the oxygen concentration of the column outflow. Conclusions: CBZ and PMD are retarded in the presence of organic matter in the aquifer. Variations of the TOC content of the sediment have a direct influence on the retardation of CBZ and PMD. The three human pharmaceuticals may be ranked in order of decreasing retardation: CBZ & PMD & SMX. The microbial activity in the experiments was not studied, although it can be assumed that the thermal pretreatment influences the microbial activity in the sediments. In particular, the microbial activity was severely inhibited at 550 °C, resulting in a shift of the redox conditions.

Municipal solid waste (MSW) in landfill bioreactors is subjected to mechanical, biological, and hydrological processes. To understand these processes, four large-scale bioreactor pilots were specifically designed to simulate the behavior of waste in the core of a landfill. Here, the results of two long-term tests that were performed in two compression cells are presented. Mechanical, biochemical, and hydrological parameters were analyzed throughout the experiments. The promising results of this research improve the understanding of biodegradation and its correlation with the hydromechanical behavior of municipal solid waste. In particular, the sensitivity of the biodegradation to leachate injection and the correlation between the biogas flow and vertical settlement were confirmed for wastes with high initial moisture content. The results showed that it is important to consider the potential of different monitoring techniques and the representative volume for the experimental approach. Furthermore, the operational results led to interesting conclusions, especially regarding the addition of moisture to waste, which is a key element for bioreactor landfill operation.

A pilot plant with a full scale monolithic ceramic membrane was operated at Ruhleben wastewater treatment plant (WWTP), Berlin Germany, for more than 12 months. Filtration performance according to the applied pre-treatment (dose of ozone and coagulant) were investigated. Trial runs with and without ozone, varying the operational parameters such as flux, coagulant dosage, and filtration time were conducted in order to identify the benefits of pre-ozonation. The reduction of the total fouling rate by ~70 % when applying a specific ozone dose between 1.0 and 1.4 mg mgDOC–1 highlights the potential of ozonation as pre-treatment step. Using LC-OCD measurements, the effect of ozone on the biopolymer concentration and the DOC fraction was demonstrated.