ENSI presents its first Action Plan based on the Lessons Learned from Fukushima

Aktionsplan Fukushima 2012The Swiss Federal Nuclear Safety Inspectorate (ENSI) intends to continue improving the safety of Switzerland’s nuclear power plants. After its analysis of the events at Fukushima, ENSI therefore defined follow-up measures for the current year relating to eleven key topics. The 2012 Action Plan deals with checkpoints that were identified last autumn in connection with the Lessons Learned, as well as open points that are listed in the Swiss national report on the EU Stress Test.

The Action Plan (PDF, german, 10 MB) for the current year covers 29 points relating to a number of issues: earthquakes, flooding, extreme weather conditions, lengthy loss of power supplies, loss of the ultimate heat sink and coolant supply, containment venting and hydrogen management, emergency management at national level in Switzerland, safety culture, experience feedback, international supervision and cooperation, and the external storage facility at Reitnau. Twelve of these points are dependent on the work undertaken by the Interdepartmental Working Group to Review Emergency Protection Measures in case of Extreme Events in Switzerland (IDA NOMEX).

Rosa Sardella, Head of the Systems Supervision Area, summarises the status of work in progress as follows: “Together with the points that we had already initiated prior to the Action Plan, we are now working on 80 per cent of the identified checkpoints and open points.” Explaining the next steps, she adds: “Additional verifications, for example regarding earthquakes, floods and extreme weather events, will allow us to assess the plants in depth on the basis of the latest knowledge. Based on these verifications and others that are already available, any measures that are necessary to continue improving the safety of Switzerland’s nuclear power plants will be initiated and implemented.” Examples include setting up a diversified heat sink and improving the seismic stability of the filtered containment venting systems.

45 points from two reports

In connection with the analysis of the events at Fukushima, ENSI identified 37 checkpoints at the end of October 2011. The inspection and verification mandates cover a number of areas: plant design, emergency management, experience feedback, supervision, radiation protection and safety culture. One key point in this context is the optimisation of emergency preparedness in Switzerland. Another eight open points were added in the Swiss National Report for the EU Stress Test at the start of this year; three of these relate to seismic protection, two are concerned with emergency management, and individual points deal with protection in case of flooding, extreme weather events and loss of power supplies.

Processing of the identified checkpoints and open points is due to be completed by 2015. To achieve this goal, ENSI will present an annual Action Plan and will report on the status of work. The list of open points and checkpoints will be continuously reviewed on the basis of the latest knowledge, and will be updated as necessary.

Since March 2011, ENSI has issued several rulings which order further investigations and measures. The immediate measures include (but are not limited to) setting up a joint external emergency storage facility for the Swiss nuclear power plants, including the necessary plant-specific connections, and back-fitting feed lines to provide external supplies to the spent fuel pools. “These measures have already enabled us to complete two checkpoints”, Rosa Sardella comments. “We shall tackle the remaining six points in a later Action Plan.”