Calculation of the Concentration of Any Radionuclide Deposited on the Ground by Offsite Fallout from a Nuclear Detonation

Abstract

A method is described to calculate the dry deposition on the ground of any radionuclide in offsite fallout from a nuclear weapons test. The method depends upon the calculation of a source term (microcuries per square meter of fission and activation products), the use of concentration-to-exposure-rate conversion factors, and normalization to a measured external exposure rate. Fractionation is treated explicitly by elimination of a fraction of the refractory elements from the source term. Calculations are in agreement with available measurements from tower-based nuclear detonations.