Simulating dissolved Sr concentrations within a small catchment in the Chernobyl Exclusion Zone using a parametric hydrochemical model.

Strontium-90 (Sr) is the major long-lived radionuclide derived from the Chernobyl accident, and is still being detected in the heavily contaminated catchments of the Chernobyl Exclusion Zone. This study examines the long-term decrease in the dissolved-phase Sr concentration and the concentration-discharge (Sr-Q) relationship in stream water since the accident. We show that the slow decline in Sr follows a double-exponential function, and that there is a clear relationship between Sr and Q.