A model for calculating the accident washout factor for a coastal nuclear power plant site

A set of deterministic and probabilistic models for estimating the accident washout factor are developed and established based on accident dispersion factor models given by current guidelines. The deterministic washout factor for different time intervals after accident release, the probabilistic was hout factor, and the dose corresponding to various pathways are estimated b ased on the measured meteorological data on the site of a coastal nuclear p ower plant to be built in the southeastern part of China. The results show that for doses obtained from 0 to 8 h after a design-basis accident release , the external exposure dose from washout deposition given by the determini stic model is similar to 55% of that from dry deposition and 22% of individ ual effective dose (except wet deposition dose); the ratios of external exp osure dose from washout to that from dry deposition and to effective dose ( except wet deposition dose) given by the probabilistic model are similar to 5.73 and 2.29, respectively.