Title: THE MATHEMATICAL MODELLING OF RADIONUCLIDE TRANSPORT IN THE SUBSURFACE ENVIRONMENT AROUND THE CHORNOBYL NUCLEAR POWER PLANT
Authors: S.L.Kivva (Institute of Mathematical Machines & Systems Problems of the Ukrainian National Academy of Sciences, 42 Glushkova Av., UA-252187 Kyiv, Ukraine)

The Shelter constructed above the destroyed Unit-4 of the Chornobyl Nuclear Power Plant contains 20 MCi of nuclear fuel. More than 1000 m$^{3}$ of intermediate-level radioactive water is disposed in its basement. The purpose of this work is to simulate migration of the radionuclides $^{90}$Sr and $^{137}$Cs from the Shelter into the subsurface environment to evaluate their migration rate and migration paths. A mathematical model accounting for the coupled transport of water and radionuclides in variably saturated media is used. The lack of suitable experimental and field studies excluded the possibility of complete validating the model. Results of the simulations will be useful for future studies of the environmental impact of the Shelter.

Comments: Figs. 11, Refs. 9, Tabs. 1.