Fukushima Daiichi

Tokyo Electric Power Fukushima Daiichi 1 (Ohkuma, 39 BWR... 

Fukushima—Daiichi Nuclear Power Plant Complex, Japan Earthquake and tsunami leading to ongoing release of radioactive materials and enormous financial loss. 

A particularly noteworthy common cause scenario occurred at the Fukushima—Daiichi nuclear power complex in Japan. On March 11, 2011, north eastern Japan was devastated by the Tohoku subsea earthquake— the most powerful ever to have hit Japan since records have been kept. The earthquake was followed about 50 minutes later by a tsunami of 14 meters in height. It is estimated that the earthquake and tsunami together resulted in 15,883 deaths, with many others injured or missing. Up to 1 milhon buildings were destroyed or damaged. 

The earthquake caused extensive damage to the structures of the Fukushima—Daiichi power plant and knocked out the pump systems that supply cooling water to the reactors and the spent fuel pools. This is known as a Loss of Coolant Accident (LOCA) takes place. 

He is equally scathing about estimates of consequence. He believes that the consequences of events such as Deepwater Horizon or Fukushima—Daiichi will always be much more serious that estimated in the risk management models. 

In Chapter 1, it was noted that the Fukushima-Daiichi catastrophe provides a good example of Common Cause events the earthquake knocked out the primary cooling pumps, and the tsunami then knocked out the backup pumps. Copies of the Fukushima-Daiichi P IDs (Piping and Instrument Diagrams) are not available. Therefore, for the sake of discussion it is assumed that there are two sets of pumps three operating pumps (Ol, 02, and 03) driven by electricity and two backup pumps (B1 and B2) that are diesel-powered and that do not require electrical power. The Fault Tree for this assumed set up is shown in Figure 15.28. It consists entirely of and Gates. 

Thoughts to do with the impact of the on-going crisis at the Fukushima-Daiichi nuclear power complex... 

D. Kamei, T. Kuno, S. Sato, K. Nitta, T. Akiba, Impact of the Fukushima Daiichi nuclear power plant accident on hemodialysis facilities An evaluation of radioactive contaminants in water used for hemodialysis. Then Apher. Dial. 16, 2012, 87-90. 

Radioactive iodine gained notoriety through the nuclear disaster at the Chernobyl power plant in 1986, which resulted in an increase of thyroid carcinomas among small children by a factor of around 10-30. It is now presumed that many of these cancer cases might have been prevented by prophylactic administration of iodide. The longer term consequences of the nuclear fallout from the Fukushima Daiichi accident in 2011, where also a number of different radionuclides were released, are still being evaluated. 

Japan Fukushima Daiichi 7 Tokyo EPCO 1380 MW - - at planing... 

Sakaguchi, A., Kadokura, A., Steier, P. et al. (2012a). Isotopic determination of U, Pu and Cs in environmental waters following the Fukushima Daiichi Nuclear Power Plant accident, Geochem. J. 46, 355-360. 

The more recent accident at Fukushima Daiichi in Japan in 2011 was different in its nature and has been internationally assessed as having released significantly lower levels of radiation. International monitoring is of crucial importance in these circumstances because of the potential for the contamination to spread across large areas of the globe. 

The Institute of Nuclear Power Operations wrote an interesting addendum to their INPO 11-005, Special Report on the Nuclear Accident at the Fukushima Daiichi Nuclear Power Station. They go on to discuss some of the lessons learned from the black swan event. Many of the lessons learned are heavily related to nuclear-specific design and operational issues however, here are some that have more universal application and again are themes that we shall see throughout this book (INPO, 2012) ... 

Behaviors prior to and dnring the Fukushima Daiichi event revealed the need to strengthen several aspects of nuclear safety culture. It would be beneficial for all nnclear operating organizations to examine their own practices and behaviors in light of this event and use case studies or other approaches to heighten awareness of safety culture principles and attributes. 

Emergency response is important for any event. The Fukushima Daiichi disaster is an example of how a natural disaster created a massive safety accident. Chapter 4 details how emergency management is part of the SMS. 

INPO. 2012, August. Lessons learned from the nuclear accident at the Fukushima Daiichi Nuclear Power Station, INPO 11-005 Addendum, Revision 0. Atlanta, GA Institute of Nuclear Power Operators, http //www.wano.info/wp-content/uploads/2012/08/11-005-Fukushima-Addendum2.pdf, downloaded March 28, 2014. 

You don t need to be reminded of the most recent nuclear accidents, principally Fukushima Daiichi in Japan in 2011. After the Three Mile Island accident in the late 1970s, the U.S. Atomic Energy Commission developed WASH 1400, The Reactor Safety Study. The WASH 1400 report laid the foundation for the use of probabilistic risk assessments (called probabilistic safety assessments in Europe). According to Henley and Kumamoto (1991), probabilistic risk assessment involves studying accident scenarios and numerically rank[ing] them in order of their probability of occurrence, and then assess[ing] their potential consequence to the public. Event trees, fault trees, and other risk-consequence tools are applied in developing and studying these scenarios. These techniques are extremely useful for the engineer but very expensive. The nuclear industry has been the leader in probabilistic safety analyses. 

The purpose of the matrix is to help you prioritize hazards for corrective aetion. The categorization of hazards is based on severity and likelihood. Some hazards may be very likely to occur but of very minor consequences. One example is the minute release of nitrogen gas from a flapper valve into a well-ventilated, open area. Even if release is frequent, the severity of the hazard is low because the quantities are so low. However, an explosion at a commercial nuclear power plant may be remote (but obviously not impossible, as demonstrated by Chernobyl, or the remote possibility of an earthquake creating a tsunami wave hits a nuclear power plant and causes a meltdown as demonstrated by the Fukushima Daiichi nuclear disaster), but the consequences are great. These two hazards must be treated differently. Engineers too often treat all hazards equally, either overreacting or underreacting to the risk. 

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