The Second 2020 Fukushima Research Conference (FRC)

In order to decommission the Fukushima Daiichi NPS, researchers in many specialized fields need to work together to solve problems.
In the past severe accidents (SA) at Three Mile Island Unit 2 (TMI-2), Chernobyl Unit 4 (ChNPP4), and Fukushima Daiichi Units 1, 2, and 3 (1F1, 1F2, and 1F3), insufficient data or data from degraded measurement instruments caused fatal mistakes in accident countermeasures, hindering reactor recovery. Based on such bitter lessons, the role of measurement method and instrumentation has been recognized as an important subject. New measurement methods and instrumentation are under consideration for providing accurate information on reactor conditions before, during and even after a SA. In addition, there still exist various unresolved issues partially due to significant adverse conditions especially during and after a SA.

After a SA, most measurement instruments in nuclear power plant (NPP) are inaccessible because of harsh SA environments that include extremely high radiation fields. However, data from selected instruments are required prior to and during recovery and decommissioning work, such as temperature, pressure, and chemical and radiation conditions. Installation of various kinds of new instrumentation with novel techniques considering specific designs of NPPs that may encounter a SA is also envisaged to establish optimum and effective recovery and decommissioning work environments.

SAMMI-2020 includes following areas on advanced and innovative measurement methods and instrumentation:

1. Establishing the current status: Review of critical information for severe accident management (SAM), emergency planning, long term management (up to decommissioning after an accident) with required criteria (range, accuracy, response and mission time), based on approaches developed or under development for NPPs, that would efficiently support comprehensive SAM strategies (both for core melt and spent-fuel pool (SFP) accidents). This would be done reviewing important feedback from the past SAs at Three Mile Island Unit 2 (TMI-2), Chernobyl Unit 4 (ChNPP4), and Fukushima Daiichi Units 1, 2, and 3 (1F1, 1F2, and 1F3).


2. Review of already implemented instrumentation (including those for DBAs), their expected performance in SA (level of qualification, reading validity, margin to failure) and their possible use in SAM, emergency planning and long-term management approaches for nuclear power plants (NPPs). Identify additional needed research, if any, to better assess their performance in a SA.


3. Identify available technologies and/or technologies under development and/or innovative technologies that would provide these major improvements, considering possible implementations, protections and expected environmental conditions and covering all accident phases, which are applicable to either of NPPs under operation and future NPP design.


4. Identify possibilities in data mining and numerical analysis techniques that could be implemented to support decisions in SAMG implementation.


5. Recommend enhancements and further R&D.