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CALPUFF is an atmospheric source-receptor model recommended by the US Environmental Protection Agency (EPA) for use on a case-by-case basis in complex terrain and wind condition. As the bulk of validation of CALPUFF has focused on long-range or short-range but long-term dispersion, we can not gauge the reliability of the model for predicting the short-term emission in near-field especially complex terrain, and sometimes this situation is important for emergency emission. To validate the CALPUFF’s application in such condition, we carried out a tracer experiment in a near-field complex terrain setting and used CALPUFF atmospheric dispersion model to simulate the tracer experiment in real condition. From the centroid trajectory comparison of predictions and measures, we can see that the model can correctly predict the centroid trajectory and shape of tracer cloud, and the results also indicate that sufficient observed weather data only can develop a good wind field for near-field. From the concentration comparison in each arc, we can see the model underestimate horizontal extent of tracer puff and can not reflect the irregular characters showed in measurements. The result of global analysis is FOEX of −25.91%, FA2 of 27.06%, FA5 of 61.41%. The simulations shows that the CALPUFF can simulate the position and direction of tracer cloud in near-field complex terrain but underestimate over measurements especially in peak concentrations.

The purpose of a consequence assessment system is to assess the consequences of specific hazards on people and the environment. In this paper, the studies on technique and method of atmospheric dispersion modeling of radioactive material in radiological risk assessment and emergency response are reviewed in brief. Some current statuses of nuclear accident consequences assessment in China were introduced. In the future, extending the dispersion modeling scales such as urban building scale, establishing high quality experiment dataset and method of model evaluation, improved methods of real-time modeling using limited inputs, and so on, should be promoted with high priority of doing much more work.

Increased concern over regional and international aspects of air pollution, acid deposition and accidental releases has created a need for air pollution dispersion model development and evaluation. Under the framework of the US-China Peaceful Uses of Nuclear Technologies (PUNT) Agreement, a program to carry out an Asian tracer experiment was proposed. In this paper, the long range tracer experiments conducted internationally and evaluation of long range dispersion models were reviewed and a preliminary planning on the former several aspects was analyzed and discussed.

This paper introduces mainly the research status and developing focuses of warning of and emergency response to nuclear and radiological terrorist incidents and discusses the system and technology of warning and emergency response to nuclear and radiological terrorist incident. The system of warning and response of nuclear and radiation incident is comprised of information acquirement and management, analysis and decision-making, and emergency response. The system is based on threat evaluation. The content and technology of the system is analyzed in the paper, in particular the importance of information flow, such as information collection, estimation, release and so on.