Safety assessment methodologies for near surface radioactive waste disposal facilities

Development of nuclear energy and applications of isotopes in medicine, industry, agriculture, hydrology, and biology have led to the generation of radioactive waste and the need for its management and disposal. This paper reviews the concepts and step wise development of safety assessment methodologies for performance evaluation of near surface radioactive disposal facilities. The safety assessment methodologies followed in a representative group of countries are explained in detail for a comparative study. The regulations and practices in the management and disposal of low level radioactive wastes arising from various stages of the nuclear fuel cycle as well as from other sources are also discussed. This includes the philosophy of radioactive waste management and disposal, multi-barrier concept, type of wastes, source terms, scenario analysis, probabilistic safety analysis, deterministic safety analysis, and finally the radiological impact assessment. (author)