Members of the research group have, within the Jožef Stefan Institute, which is an authorized expert organisation for radiation and nuclear safety, prepared an independent evaluation of the reports covering the modified Krško 16×16 VANTAGE+ fuel design. Some safety analysis report changes regarding fuel mechanical design changes, reanalysis of large break loss of coolant accident with revised grid parameters and lower than expected critical heat flux results obtained during departure of nucleate boiling testing are suggested.
F.04 Increase of the technological level
COBISS.SI-ID: 29466919The expert opinion refers to the revised Krško nuclear power plant (NEK) safety upgrade program (SUP, Rev.2) and accompanying analysis reports, by which NEK justifies the appropriateness and integrity of their actions for prevention and mitigation of selected severe accidents. The changes in the SUP, compared to its last revision (approved by the Slovenian Nuclear Safety Administration), and the conceptual design of proposed alternate systems for core and containment cooling, were evaluated. The present expert opinion on revised SUP and accompanying reports has been based on the Jozef Stefan Institute expertise and experience, including deterministic analyses as well as international practice.
F.04 Increase of the technological level
COBISS.SI-ID: 28742695Members of the research group have, within the Jožef Stefan Institute, which is an authorized expert organisation for radiation and nuclear safety, monitored the activities during the regular outage of the Krško nuclear power plant in 2016. The monitored outage activities consisted of testing of safety structures, systems and components, refueling activities, visual and ultrasound inspection of fuel elements and reactor physics related tests of core and startup tests of the reactor.
F.30 Professional assessment of the situation
COBISS.SI-ID: 29987623The Slovenian Agency for Radwaste Management (ARAO) is planning the construction of a repository for low and intermediate level radioactive waste in the next few years. At present, ARAO is preparing the document "Project design basis for low and intermediate level radioactive waste repository Vrbina, Krško", Rev.0. Members of the program group have, as Jožef Stefan Institute experts, prepared a review of the document. The review was focused on compliance with the Slovenian nuclear legislation. In addition, the compliance with international regulations, recommendations and examples of good practice in the field of radioactive waste disposal were also addressed.
F.30 Professional assessment of the situation
COBISS.SI-ID: 28884263The method and apparatus for assessing the state of a spent-fuel facility are based on monitoring the trend of measurable parameters that are directly related to the coolant level elevation in the spent fuel pit. They enable early detection of consequences of the initiating event, characterizes eventual damage in the spent fuel pit (SFP) envelope and predicts further development of the event. In fact, by precisely measuring the trends of either coolant leakage, cooling water level elevation or dose rate at the edge of the pool during short period of time after initiating event, it is possible to assess the eventual crack in the SFP envelope and, for given scenarios, provide predictions of the cooling water level elevation, i.e., foreseeing dose rate at the edge of the pool, eventuality of uncovering the core, drawing attention to the risk of fire and large releases of radioactive materials into the environment.
F.33 Slovenian patent
COBISS.SI-ID: 28441383