An integrated system of mathematic models is developed and implemented. The system is aimed at predicting the spread of the radioactive materials in the Arctic waters from a complex source distributed in space and time, formed by an emergency release of radionuclides from a nuclear-powered facility. Such approach allows taking into account various mechanisms of radionuclide transfer in arbitrary combinations. In addition to customary considered atmospheric and marine advection-diffusion processes with sedimentation on the underlying surface, it takes into consideration other mechanisms. Among them are particle sedimentation to the sea bottom with bottom capture, reverse process of washing-out from the bottom sediments. Specially attended is the Arctic-specific mechanism of particle ice-binding in the sea ice, drift of the frozen particles with ice, and their return to marine environment in result of ice thawing. The latter process may result in the appearance of the radioactive source at the large distance from the initial source and long time after the release event. The integrated model complex will provide the most realistic picture of the radioactive trace spread. It will sure be the effective tool for minimizing the emergency negative impact on the population and environment. The article a stage of long-term work that is currently ongoing.