USE OF AQUATIC MOSSES FOR MONITORING ARTIFICIAL RADIONUCLIDES DOWNSTREAM OF THE NUCLEAR-POWER-PLANT OF BUGEY (RIVER RHONE, FRANCE)

The detection of radionuclides in water, downstream of nuclear install ations located on river banks, is often very difficult notably because of their low concentrations. Thus the use of biological indicators is an interesting process to detect radioactive contamination of an aqua tic ecosystem. From 1986 to 1990, artificial radionuclides were measur ed in freshwater mosses sampled downstream of the nuclear power statio n of Bugey. These field data on the whole, have shown a comparatively good qualitative and quantitative relationship between radioactive com position of liquid waste and radionuclides detected in mosses. In othe r respects, the results showed up a relatively clear hierarchical stru cture in the affinity of the different radionuclides for the mosses. T o specify these relations, mesh bags containing allochtonous mosses we re immersed at four stations downstream of the power plant and regular ly sampled during a 10-h waste discharge period.