Speaker
Description
The environmental monitoring program of the Danube was established in 1987 with a single sampling location at Vienna Nussdorf. In 1989 and 1992 the program was extended to three additional locations (Ottensheim, Wallsee, Greifenstein). The radioecological study was performed by the BOKU University – partly on behalf of the Austrian Federal Ministry of Agriculture, Regions and Tourism (BMLFUW). Thanks to this study, valuable long-term data of over 25 years are available. The sampling occurred continuously, in almost uninterrupted time series. One of the biggest goals of this long-term study was to assess long-term behaviour of the large-scale radioactive environmental contamination in the alpine ecosystem of the Danube.
However, in 2017 the Austrian Agency for Health and Food Safety (AGES GmbH) has been assigned by BMLFUW to continue the monitoring of the radioactivity in the Danube. Due to changed regulations at hydropower plants, on-site sampling was now longer possible. The sampling has been performed at the location of the run-of-river power plants by VERBUND AG, whereby a continuous, automated water sampling has been taken in monthly intervals.
Furthermore, the monitoring program changed by including plutonium isotopes and strontium-90 in the analysing program. These artificial radionuclides have been in the Chernobyl fallout as well as in the global fallout caused by nuclear weapon testing.
When the monitoring at AGES GmbH started, the radiochemical separation was performed sequentially with DOWEX™1x8 and Sr®Resin. However, a radiochemical method has been established for the simultaneous separation of plutonium isotopes and Strontium-90 using Sr®Resin by Triskem International. The measurement was performed by alpha-spectroscopy and liquid scintillation counting, respectively. To reach lower detection limits, monthly samples have been combined to two-month samples or yearly samples.
Here we present analytical results of over 400 samples and a detailed description of the separation of Plutonium isotopes and Strontium-90 using Sr®Resin.
These investigations were funded by the Federal Ministry of Agriculture, Forestry, Regions and Water Management of Austria.