Safety and environmental problems of INTOR/NET

Safety and environmental studies for INTOR/NET are performed jointly by several European laboratories. Three features of this work are described: The methodology which is applied in the risk analysis. A list of severe accidents is established and progressively revised after studying the consequences of each accident and the safety features which reduce the risk (probability x consequences). Design options are compared on the basis of residual risk (CEA-FAR). The effects of routine and accidental tritium releases are evaluated under different conditions, i.e. chemical form, concentration in air and deposition on soil. Even with conservative hypotheses, the dose rates due to the anticipated routine releases are much lower than the ICRP limits and compare favourably with the limits given for fission plants on the basis of cost-benefit analysis. A proper subdivision of the tritium inventory in the plant can limit the accidental releases and their effects (Studsvik). Experiments are performed to assess the chemical reactivity of the eutectic Li17Pb83 which is considered a possible breeder material. The reactivity in air is mild. Water-eutectic interactions produce small amounts of hydrogen (JRC Ispra). (author)