Sr-90 in lake sediments

For a better understanding of the behaviour of Sr-90 in aquatic systems, this beta-emitter has been determined in the different layers of a lake sediment core which has been previously dated using the well established Pb-210 dating method. For this, a radiochemical technique has been developed for thr isolation of strontium from the sediment samples and for its beta activity measurement with a low-level gas-flow proportional counter. A conservative behaviour of Sr-90 in the water column, remaining dissolved in the water body, can be inferred from the data obtained. Consequently, a possible Sr-90 transport pathway through the outflowing waters of the lake can be deduced.