Das Projekt "Teilprojekt: Migrationsverhalten umweltrelevanter Spurenstoffe unter wechselnden Milieubedingungen im oberflaechennahen Grundwasserleiter des Oderbruchs" wird vom Umweltbundesamt gefördert und von Freie Universität Berlin, Institut für Geologische Wissenschaften durchgeführt. Ziel des Projektes ist die Charakterisierung der Stoffdynamik in unterschiedlichen Milieubereichen des Grundwasserleiters an der Kontaktzone zwischen einem anoxischen Aquifer und dem oxischen Grabensystem des Oderbruchs. Der Einfluss der Graeben auf die hydrochemische Ausbildung des Grundwassers ist auf Grund der extremen hohen Gradienten qualitativ und quantitativ schwer zu beurteilen. Durch Untersuchungen im Gelaende mit einer genauen hydrochemischen und hydraulischen Charakterisierung der vorhandenen Redoxzonen in Verbindung mit experimentellen Saeulenversuchen im Labor werden die in den Redoxuebergangsbereichen ablaufenden Prozesse detailliert untersucht und eine Bilanzierung der Stoffumsetzungen durchgefuehrt. Die Arbeiten sollen Aussagen ueber die Langzeitwirkung der Senke/Quelle 'Redoxfront' machen.
Das Projekt "DYTRAC: Dynamik des Transports und der Transforamtion von Colloiden und Partikeln im Lago Ceresio (Lugano-See)" wird vom Umweltbundesamt gefördert und von Universite de Geneve, Institut F.-A. Forel durchgeführt. Removal rates of many pollutants in lake water are controlled by their partition between dissolved, colloidal and particulate fractions. We are investigating this partition using natural radioactive Be isotopes as surrogates for these pollutants. A new particle separation system for big lake water samples (1000 liters) consisting of a continuous flow centrifuge and an ultra filtration device has been developed. In epilimnion of Lake Lugano we are able to measure Be-7 in all 3 fractions. The largest part is found in the dissolved fraction. This may explain the relatively long residence time of Be in lakes. The work has been accompanied by a series of methods aimed at characterising the physico-chemical conditions in the lake at the time of sampling, the nature of the recovered particles, as well as the performance of the system. Electron microscope observations show decreasing number of particles and their sizes from raw to centrifuged and to ultra filtered water. Pilot measurements to study particle dynamics in the deep water have been carried out including tritium-helium water age measurements. Leading Questions: - What is the role of colloids in removal of metals and radionuclides from lake water? - Can Be-7 be used to determine coagulation rate in lakes? - What is the importance of Fe and Mn cycling at redox interface in permanently stratified lake for phosphorous transport? Other objectives of this project are the following: - Determine the role and importance of Fe and Mn cycling at the oxic-anoxic interface for phosphorous fluxes, - assess the nature of fine particles in lower hypolimnion and their transport mechanism (coagulation, settling, resuspension, focusing)?
Das Projekt "Puxbaum-TU" wird vom Umweltbundesamt gefördert und von Universität für Bodenkultur Wien, Institut für Wasservorsorge, Gewässerökologie und Abfallwirtschaft, Abteilung für Siedlungswasserbau, Industriewasserwirtschaft und Gewässerschutz durchgeführt. Es werden Kläranlagendaten und Wasser- und Luftemissionen erfasst.
Das Projekt "Arsenic contamination of Ogosta river: Linking biogeochemical processes in floodplain soils with river system dynamics" wird vom Umweltbundesamt gefördert und von Eidgenössische Technische Hochschule Zürich, Institut für Biogeochemie und Schadstoffdynamik durchgeführt. The sustainable management of land, which has been heavily contaminated by industrial or mining activities, poses an important challenge to many industrialized countries, including Bulgaria. This project focuses on arsenic (As) contamination in NW Bulgaria, where the floodplains of the Ogosta river received large amounts of As-rich mining wastes near Chiprovtsi between 1964 and 1979. The goals of the project are (i) to investigate the magnitude and spatial distribution of As contamination in floodplain soils and sediments in relation to river system dynamics, (ii) to improve the process-oriented understanding of As release from soils to river and groundwater by microbial and physico-chemical processes during periods of low and high flow, and (iii) to explore advanced approaches for integrating process-oriented, molecular scale knowledge and river-system scale information to better understand As speciation, As fluxes, and impacts on water quality at the river-system scale. The project is expected to yield novel process-oriented knowledge on the dynamics of As in highly contaminated river floodplains. New ways of integrating molecular-scale and river-system scale information will be explored, which can then also be applied to other river systems in Bulgaria. The project will provide the scientific basis for river management and potential remediation strategies for Ogosta river. Ultimately, it will help protect the local population from adverse health effects arising from the legacy pollution with As and other heavy metals by former mining.