Radionuclide dispersion from forest fires

Following the Chernobyl nuclear plant accident a great deal of radionuclides has been deposited in the soils of eastern Europe. A large proportion of the radionuclides have been deposited in the upper layer of the soil or have been absorbed by uptake in the plants of the area. During forest fires or other environmental disasters small particles from the soil or plants become airborne. The radionuclides which are attached to the airborne particles are thus carried in the atmosphere and transported to other areas. In this manuscript we examine the dispersion of small particles from a thermal plume. The governing equations of the plume are solved numerically to yield the temperature and velocity fields in the vicinity of the plume source. A Monte Carlo method is used for the calculation of particle dispersion. Particle trajectories in the plume are computed until either the particles elevate up to 500 m from the surface or are deposited on the horizontal ground surface. Hence, the redistribution of the radionuclides in the region is determined by statistical methods.