After Fukushima: The Nuclear Zombie in Your Backyard

On 2011/08/27, at 8:51, mary mycio wrote:

Nuclear family bonds

Mary Mycio, J.D.
West Chester, PA

Wormwood Forest: A Natural History of Chernobyl

Dear Ms. Mary Mycio:

I hope your new manuscript on a side view of the Fukushima disaster:

After Fukushima: The Nuclear Zombie in Your Backyard: Should You Be Afraid?

is going to be published, since I included you in my mailing list hoping that you might be inspired to write such a book.

I hope that the Fukushima disaster is not going to be dismissed as in the case of the Chernobyl accident by the western nuclear community, simply by composing a statement essentially saying that the accident occurred in a special design of the Soviet Union, without the containment vessel, and is not relevant to the current nuclear power plants of the Western countries. "The Fukushima disaster was induced by the tsunami. Without tsunami, such an accident is not relevant to other countries."

Looking into the details of the design, necessary safety systems are also provided in the Chernobyl reactor including, an Emergency Core Cooling System (ECCS), Pressure Relief System in the main coolant circuit, Confinement System, Pressure Suppression System, Isolation System to establish the confinement function, Hydrogen Removal System and an Emergency Power Supply System [ USSR State Committee on the Utilization of Atomic Energy, $B!H(BThe Accident at the Chernobyl$B!G(B Nuclear Power Plant and Its Consequences,$B!I(B Information compiled for the IAEA Experts Meeting, 25-29 August 1986, Vienna, Part II, Annexes 2.7 (1986)].

An important point for consideration is that the Chernobyl reactor did not have a reactor containment system which accommodates practically total inventory of primary coolant leakage into the reactor space; although a Confinement System of a limited capability was installed as an alternative. The reactor space of the Confinement System had a limited capability for overpressure protection. Under the Chernobyl NPP Phase II design, a portion of the primary coolant loop was located outside of the reactor space (this portion is called the reactor vessel in this paper, although there exist no such thing in the pressure tube reactors) surrounding the reactor and associated major equipment. The rooms containing this portion of the loop were provided with special blowout panels to support a controlled discharge of radioactive steam and gas into the atmosphere, in the event of a pipe break involving a diameter of up to 300 mm. The further details of the accident sequence is compiled in my previous paper: (G. Saji, 2005. Management of Nuclear Risks by Intrinsic Safety, Siting, and Defense-In-Depth for Future Reactors: Lessons Learned from the Chernobyl Accident, In the Proceedings of International Topical Meeting on Probabilistic Safety Analysis, PSA$B!G(B05 11-15 September 2005, San Francisco, California, USA.)

In contrast to the Chernobyl accident, all of the containment vessels appear to have survived the active phase of the severe accident, although all of them are leaking. This fact has been demonstrated only recently, by identifying surprisingly low radioactivity levels inside of the Reactor Pressure Vessels as well as being able to maintain an inert gas atmosphere through nitrogen gas injection. It is now becoming clear that al least an "in-vessel retention" in which core debris are still kept inside of the Reactor Pressure Vessels. Whereas a significant portion of the core materials, including approximately 3-5% of fuel particles, have been released to the environment from the Chernobyl accident. The Fukushima-Daiichi accident is by far not comparable to the Chernobyl accident, in view of retention of harmful radioactivities.

Also, when I was reading the decontamination handbook for re-habitation issued by EURANOS, I was amazed to find that no one seems to have any notion that the power reactor could explode in just one day, the 1F1 hydrogen explosion occurred in just one day after the arrival of tsunami, at 15:36 on March 12. The handbook intrinsically assumes that there will be enough time for people to evade radiation risks. The NISA/TEPCO's official scenario is early core melt through. It is hard to support their view for me, since the "feeding and bleeding" operation has been completely ignored in their analyses. Also wealth of sampling data do not support this scenario, I believe. There must be some scientific root causes that we are ignorant in the mechanism of the early hydrogen explosion.

However, in Japan, news media just passed through NISA/TEPCO story without being able to perform their own critical review, resulting in endorsing their official scenario. Although the Government installed Investigation Committee on the Accident at the Fukushima Nuclear Power Stations (http://icanps.go.jp/eng/) inside the Cabinet, they are focusing on the "organizational accidents"

( http://rmc.nasa.gov/archive/rmc_v/presentations/reason%20managing%20the%20risks%20of%20organizational%20accidents.pdf )

Certainly this is a very important view point, however, it is equally important to investigate the Fukushima-Daiichi accident from a scientific and engineering point of view and extracts lessons learned from the disaster. Unfortunately, no such initiative is visible inside Japan.

I believe it is necessary to have an International Fukushima-Daiiichi Center, an equivalence of the International Chernobyl Center (http://www.chornobyl.net/en/). The Chornobyl Center started its operation in the area of studying the consequences of the Chornobyl accident, nuclear and radiation safety, nuclear facilities decommissioning. I am concerned with the current internal situation that these activities are being performed inside Japan, in a very closed society, protected with our language barriers. Many Japanese scientists appear to think that international collaboration is not their business, but should be performed by a special organization that is responsible for interfacing with foreign countries.

Genn Saji