Thursday, September 20, 2012

Post # 70: The Structure of the U.S. Fukushima Response

With this post I begin the promised series in which I hope to provide a structured and concise chronicle of the U.S. nuclear industry's ongoing response to the Fukushima Dai-ichi accident and the the evolving "lessons-learned" from it.

In the wake of the Fukushima Dai-ichi incident, the U.S. Nuclear Regulatory Commission (NRC) convened a "Near-Term Task Force" or "NTTF" to examine the events at Fukushima Dai-ichi and offer recommendations regarding actions the NRC should take to enhance commercial nuclear power safety in the U.S. in the light of evolving lessons learned from the event.  The NTTF report,   "Recommendations for Enhancing Reactor Safety in the 21st Century – the Near-Term Task Force Review of Insights From the Fukushima Dai-ichi Accident," (SECY-11-0093, 12 July 2011) concluded there was imminent danger from continued operation of U.S. nuclear power plants, but did present "Twelve Recommendations" for actions the NRC and its licensees should take to further enhance the safety of commercial nuclear power.  

Following issuance of the NTTF report, the NRC Commission asked (SRM-SECY-11-0093) the NRC Staff to examine the NTTF's Twelve Recommendations, and to prioritize them in a logical manner based on the urgency of required actions, and the inter-relationships and inter-dependencies of the various issues.  The NRC Staff's initial recommendations regarding the subset of actions requiring the most urgent action were presented in SECY-11-0124.  Subsequently,  SECY-11-0137 presented the NRC Staff's recommendations for a three-tired prioritization.  This three-tiered hierarchy was accepted by the NRC Commissioners, and became the organizational foundation of the U.S. response to the accident at Fukushima.

Before I continue, I should point out that, as NRC Chairman Macfarlane said a few days ago in her remarks at the IAEA in Vienna, the current structure of the NRC's and the Industry's response to Fukushima is likely to evolve away from the simple "12 Recommendations" approach presented in the Near-Term Task Force (NTTF) report.  Here are Chairman Macfarlane's words,

" As we move forward in the evolution of our nuclear safety culture, we must address the fact that the majority of post-Fukushima activities were placed in special categories. In the period immediately following Fukushima, this approach made the most sense. In the United States, for example, we established a task force to address the impacts of the accident on our domestic program, and then a special Fukushima-related directorate to implement the ensuing recommendations. The NRC is now beginning to transition these Fukushima lessons-learned programs from special, segregated actions back to the offices that handle these matters on a routine basis. Far from minimizing these activities’ importance, this approach will ensure that the lessons we have learned are fully integrated into our regulatory work in the United States. We believe that by weaving the lessons learned from Fukushima into nearly all of our regulatory activities, we are ensuring their long-term sustainability, and encourage our international colleagues to do the same.

So... now for the Twelve Recommendations as presented in SECY-11-0093....

1. The Task Force recommends establishing a logical, systematic, and coherent regulatory framework for adequate protection that appropriately balances defense-in-depth and risk considerations

2. The Task Force recommends that the NRC require licenses to reevaluate and upgrade as necessary the design-basis seismic and flooding protection of structures, systems, and components for each operating reactor

3. The Task Force recommends, as part of the longer term review, that the NRC evaluate potential enhancements to the capability to prevent for mitigate seismically induced fires and floods

4. The Task Force recommends that the NRC strengthen station blackout mitigation capability at all operating and new reactors for design-basis and beyond-design-basis external events

5. The Task Force recommends requiring reliable hardened vent designs in boiling water reactor facilities with Mark I and Mark II containments

6. The Task Force recommends, as part of the longer term review, that the NRC identify insights about hydrogen control and mitigation inside containment or in other buildings as additional information is revealed through further study of the Fukushima Dai-ichi accident

7. The Task Force recommends enhancing spent file pool makeup capability and instrumentation for the spent fuel pool.

8. The Task Force recommends strengthening and integrating onsite emergency response capabilities such as emergency operating procedures, severe accident management guidelines, and extensive damage mitigation guidelines.

9. The Task Force recommends that the NRC require that facility emergency plans address prolonged station blackout and multiunit events.

10. The Task Force recommends, as part of the longer term review, that the NRC pursue additional emergency preparedness topics related to multiunit events and prolonged station blackout.

11. The Task Force recommends, as part of the longer term review, that the NRC should pursue emergency preparedness topics related to decision making, radiation monitoring, and public education.

12. The Task Force recommends that the NRC strengthen regulatory oversight of licensee safety performance (i.e., the Reactor Oversight Process) by focusing more attention on defense-in-depth requirements consistent with the recommended defense-in-depth framework.

Things are a bit more complicated than this simple list, because each of the Twelve Recommendations (except for # 3)  were parsed into two or more sub-recommendations (e.g. 1.1, 1.2, 1.3, and 1.4).   Those seeking to monitor U.S. progress in addressing the Twelve Recommendations find their task complicated further because the three-tier prioritization of the Twelve Recommendations was done at the sub-recommendation level rather than at the top level. Thus, Recommendation 5.1 is a Tier-1 priority, while Recommendation 5.2 is a Tier-3 priority.

I will end this post here.  Future posts will discuss the sub-recommendations for each of the Twelve Recommendations, the prioritization of the sub-recommendations, actions taken to date by the U.S. NRC and the nuclear industry to address each sub-recommendation, future directions for continued progress, etc.

Again, my goal in this series of posts is not to provide an exhaustive review of all the safety-related activities in the industry.  I'm simply attempting to "status" U.S. progress in the key areas identified by the NTTF in a structured, clear, and simple manner that enables the non-expert to understand and track the post-Fukushima evolution of U.S. commercial nuclear power safety.


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