Application of Decision Support System during the Emergency Exercises for Nuclear Emergency Management

Abstract

In India, two independent decision support system (DSS) systems are developed and implemented at NAPS (Narora Atomic Power Station) and MAPS (Madras Atomic Power Station) sites for emergency response. The simulation results of the DSS systems guides in identification of emergency zones and distances and implementation of the protective actions. This paper describes application / testing of the three decision support systems developed by IGCAR, NPCIL and SRI (AERB) for dose projections and decision on the implementation of the protective action in the public domain during the recently conducted emergency exercise at NPP site. Thus three DSS systems developed in India were applied to perform atmospheric dispersion and dose assessment in public domain around the nuclear power plants (NPPs) during the recent emergency exercise. The hypothetical accident scenario was considered for the exercise. The source term estimated based on plant parameters and pre calculated source term for large number of accident scenarios was used during the exercise. The results of the assessments by using these Decision support systems were presented to the decision makers for recommendation and implementation of protective actions such as evacuation, sheltering, KIO3 distribution, contamination control etc. The Numerical Weather Forecast model was used for the area around the NPP to produce the meteorological parameters that were further used by these DSS system. Predictive assessments of the radiological situation in the vicinity of the NPP site was performed during emergency exercise with various source terms. Taking into account the high uncertainties in the source term estimation and inputs to the simulation models, the simulated results from these three DSS show a reasonable agreement. The study demonstrated the utility of DSS systems for the assessment of the radiological consequences of hypothetical nuclear accidents during the emergency exercises at different NPP sites. The experience gained in using the DSS systems for operational application to the Indian NPPs will be further used by the exercise planners and developers to improve the system continuously and their adaptation to all NPP sites in India.