Activity concentration of food after a NPP loss of coolant accident with large containment leakage. Part 1: text

This report describes the effect of different accident management strategies on the source term for a 'Loss of Coolant (LBLOCA)'-type sequence with a very large containment leakage in a pressurized water reactor of the type VVER-1000 up to the time when no more fission products are released from the core-concrete-interaction because the temperature of the debris is so low that it solidifies. Using the source term code package (STCP) the following scenarios were calculated: reference case without spray and LP ECC systems; all spray and LP ECC systems including the coolers, are available after 2,5 hours; all spray and LP ECC systems including the coolers, are available after 1,5 hours; no spray and LP ECC systems, but intact containment at beginning. These radioactive releases served to determine activity concentrations of 4 selected foodstuffs using the dispersion-code PC-COSYMA and the radioecological code OECOSYS. The analysis of the results is the basis for decisions to reduce the activity concentrations of foodstuffs and the radiation exposure of the population. (author)