IAEA team of experts went on a fact finding mission in the Tohoku region from May 24 - June 1, 2011.
What is interesting is that IAEA team not only visited Fukushima Dai-ichi nuclear power plant, but also other nuclear power plants (Tokai, Higashi Dori, Onagawa and Fukushima Dai-ni) hit by the massive earthquake and large tsunami waves. Although the large tsunami waves affected all these facilities to varying degrees, TEPCO`s Fukushima Dai-ichi came out as the one with the most severe consequences.
So, what happened at TEPCO's Fukushima Dai-ichi?
Although all electrical power was lost when the earthquake occurred, the automatic systems successfully inserted all the control rods into its three operational reactors 1-3. In addition, all available emergency diesel generator power systems were in operation.
However, the 14-meter high tsunami waves washed away all power sources except for one emergency diesel generator that provided emergency power to be shared between reactors 5 and 6. Without power, reactor control or instrumentation on site, the TEPCO operators also had problems with communications systems both within and external to the site.
Without the cooling systems for the reactors, Units 1-3 quickly heated up due to usual reactor decay heating. The rest is history.
Here is an excerpt of the report:
"1. 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.
2. 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.
3. 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.
4. 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.
5. 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.
6. 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.
7. 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.
8. Severe long term combinations of external events should be adequately covered in design, operations, resourcing and emergency arrangements.
9. 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.
10. Hydrogen risks should be subject to detailed evaluation and necessary mitigation systems provided.
11. Emergency arrangements, especially for the early phases, should be designed to be robust in responding to severe accidents."
The IAEA report covers both the good and bad points of Japan's nuclear crisis.
Japan earns good marks (nos. 1-4) in terms of dealing with orderly evacuation of the affected people in the devastated area and the efforts of the TEPCO operators who are dedicated and determined to tackle the nuclear crisis.
Japan earns bad marks for poor planning of the nuclear power plant sites (nos. 5 & 8), lacking adequate emergency arrangements for severe accidents (nos. 6,9,11), and the cozy relationship between the Nuclear regulatory systems with the nuclear power companies (no. 7), not following the line of IAEA Safety Standards.
In reality, the report doesn't help to contain the nuclear crisis, but to reiterate what is already well known about the deficiency, inadequacy and inefficiency of TEPCO, along with the government nuclear agency, in dealing with the pressing nuclear disaster. What IAEA needs to provide is a sensible road to control and contain the nuclear crisis, which we haven't seen yet.
Under closer scrutiny, the report doesn't address the poor crisis management that we are witnessing today at Fukushima power plant - unmanageable tons of radioactive water at the site, continuation of radiation leaks from the facilities, and the worsening of the nuclear crisis.
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