Modeling Fukushima Dose Consequences with EPZDose

This paper introduces the recent developments and improvements of EPZDose and illustrates the evaluation methods of dose consequences from Fukushima Daiichi NPP accidents with available released source terms and meteorology data. EPZDose is a simulation code which can evaluate and display the dose consequences, faster than real time, in the surrounding area for radioactive materials release accidents such as possible nuclear power plant severe accidents or radioactive dirty bomb threat. With given source terms and the meteorological conditions (wind velocities, directions, Pasquill’s stability conditions, and fallout fraction), the code then evaluates and plots the distributions of whole body and thyroid doses by using Modified Gaussian Plume Model and proper dose conversion factors. We adopted this tool to evaluate the dose consequences from Fukushima Daiichi NPP. Our preliminary studies already indicated encouraging, within orders of magnitude results, compared with other publications. Further refinements of our modeling are under investigations.