Safety against releases in severe accidents. Annual report 1996

The work scope of the RAK-2 project is divided into three sub-projects: RAK-2.1 Severe Accident Phenomenology; RAK-2.2 Computerised Accident Management; RAK-2.3 Reactors In Nordic Surroundings. The work in subproject 1 progresses roughly according to budget and time schedule. Some adjustments in the technical work scope were made during 1996.

Main tasks of RAK-2.1 in 1996: Complete recriticality studies for Nordic BWRs; Investigate phenomena related to late phase melt progression; Issue and NKS Final Technical Report on KTH experiments. Main tasks of RAK-2.2 in 1996: CAMS would be further developed with signal validation, tracking simulation, state identification and PSA and risk monitoring applications; Carry out a feasibility study for development of a PWR version of CAMS in collaboration with EdF, France; Use CAMS in the Halden Man-Machine laboratory to perform human factor studies.

Main tasks of RAK-2.3 in 1996: Collect and report data from the British reactor types AGR, MAGNOX and PWR; Make a report on accidents in nuclear ships; Put the collected data together in a common data base covering neighbour reactors treated in SIK-3 and RAK-2.3; Update the data in the former SIK-3 report if needed.

The work in project 2 progresses according to plans. The data collection of British reactors with in sub-project 3 has been delayed significantly due to difficulty of obtaining information from some of the British utilities, but the problems are expected to be solved by the end of 1997. (EG).