In case you missed it, last week the International Atomic Energy Agency (IAEA) released the preliminary report of their Fact Finding Mission to Japan. (http://iaea.org/newscenter/focus/fukushima/missionsummary010611.pdf)
The expected observation that the tsunami threat was underestimated has gotten most of the headlines. More interesting to me, however, was the mention of remediation efforts in contaminated areas to allow people to resume their normal lives. Once the reactors are completely “turned off” (which may take the rest of this year and beyond), these issues of decontamination, radiation risk assessment and communication with the public will be a running public learning exercise for the next nuclear power disaster or dirty bomb.
There are already indications that the Japanese government has already stumbled in this arena: raising radiation limits for children without explaining the decision to the public or efforts to take simple measures to decontaminate schoolyards near the Fukushima plant.
Interesting as well is the fact that security is never mentioned explicitly, though references are made to “extreme external events.” The nuclear power industry is hesitant to engage issues of security in addition to safety, regardless of the fact that a terrorist attack might also aim to disrupt the primary and backup power systems of a nuclear power plant with the purpose of causing similar consequences. Hopefully, the earthquake/tsunami combination that led to the nuclear meltdown will drive planning for simulataneous and unexpected events, including terrorist attacks.
The report also underlines the point that the physical impact on people of the radiation release has been minimal: “To date no health effects have been reported in any person as a result of radiation exposure from the nuclear accident.” So much attention here in the U.S. has focused on the nuclear disaster that it is easy to forget we’re worried about events that haven’t led to one death while not seriously considering how we would handle events that could kill tens of thousands.
The main preliminary findings and lessons learned are:
- The Japanese Government, nuclear regulators and operators have been extremely open in sharing information and answering the many questions of the mission to assist the world in learning lessons to improve nuclear safety.
- The response on the site by dedicated, determined and expert staff, under extremely arduous conditions has been exemplary and resulted in the best approach to securing safety given the exceptional circumstances. This has been greatly assisted by highly professional back-up support, especially the arrangements at J-Village to secure the protection of workers going on sites.
- The Japanese Government’s longer term response to protect the public, including evacuation, has been impressive and extremely well organized. A suitable and timely follow-up programme on public and worker exposures and health monitoring would be beneficial.
- The planned road-map for recovery of the stricken reactors is important and acknowledged. It will need modification as new circumstances are uncovered and may be assisted by international co-operation. It should be seen as part of a wider plan that could result in remediation of the areas off site affected by radioactive releases to allow people evacuated to resume their normal lives. Thus demonstrating to the world what can be achieved in responding to such extreme nuclear events.
- The tsunami hazard for several sites was underestimated. Nuclear designers and operators should appropriately evaluate and provide protection against the risks of all natural hazards, and should periodically update these assessments and assessment methodologies in light of new information, experience and understanding.
- Defence in depth, physical separation, diversity and redundancy requirements should be applied for extreme external events, particularly those with common mode implications such as extreme floods.
- Nuclear regulatory systems should address extreme external events adequately, including their periodic review, and should ensure that regulatory independence and clarity of roles are preserved in all circumstances in line with IAEA Safety Standards.
- Severe long term combinations of external events should be adequately covered in design, operations, resourcing and emergency arrangements.
- The Japanese accident demonstrates the value of hardened on-site Emergency Response Centres with adequate provisions for communications, essential plant parameters, control and resources. They should be provided for all major nuclear facilities with severe accident potential. Additionally, simple effective robust equipment should be available to restore essential safety functions in a timely way for severe accident conditions.
- Hydrogen risks should be subject to detailed evaluation and necessary mitigation systems provided.
- Emergency arrangements, especially for the early phases, should be designed to be robust in responding to severe accidents.