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information about Fukushima published in English in Japanese media info publiée en anglais dans la presse japonaise

Hydrogeologists, gov't monitoring, better system to reuse water & constant attention

October 14, 2013


FUKUSHIMA WATER CRISIS: Water recycling system urgently needed, ex-chairman of U.S. nuclear watchdog says




By SHIRO NAMEKATA/ Correspondent

WASHINGTON--Japan urgently needs an effective system that reuses radiation-contaminated water to cool down the crippled reactors at the Fukushima No. 1 nuclear plant, said Gregory Jaczko, former chairman of the U.S. Nuclear Regulatory Commission.

In an interview with The Asahi Shimbun, the nuclear expert said failure to handle the contaminated water problem at the site will damage Japan’s credibility.

Excerpts from the interview follow.


Question: As an outside expert, how do you view the serious problem of contaminated water leaks at the Fukushima nuclear power plant?

Jaczko: There is a long-term challenge in Japan with the clean-up from the Fukushima nuclear accident, which is going to take decades to resolve, and this is just one of the first incidents to show that it needs continuous focus and attention.

What I saw was somewhat surprising: the lack of monitoring of the tanks. That seems to be something that is more straightforward and easier to do--to ensure that there are not spills, or when there are spills, they are identified readily and quickly addressed and remediated.

But it did not appear that they had any type of instrumentation, monitoring, for those tanks; it was done as “walk-arounds” and identified by workers. They demonstrate a weakness in the safety system, in the oversight and the management of the project, and I think what is needed is corrections for those elements.

Q: Critics say that Tokyo Electric Power Co., the plant’s operator, has already lost control of the situation. What do you think?

A: It is unfortunate that TEPCO has not done more to address the situation. It has continued to raise concerns about their ability to do that, but it is also not an easy task to replace TEPCO because there are a number of workers who are involved in this effort. You cannot simply replace all those workers.

Fundamentally, this issue comes down more to management and safety focus than anything else.

What is really needed is an effective, rigorous system of accountability and management at the site. And ultimately, that has to come from the bulk of the workers and the people who are there every day.

But there needs to be continued government oversight. The regulator should continue to play a strong role in ensuring that the activities that go on at the site are safe, that they are consistent with the requirements.

There should be experts within the regulator who understand hydrogeology and the groundwater issues.

Whenever you are designing, siting and licensing nuclear power plants, you have to prepare for spills and other ways that the groundwater can be contaminated.

So, again, if the regulator does not have those experts, it would be important to hire them so that it could continue to provide effective oversight of TEPCO’s activities.

Q: If you were responsible for the situation, how would you manage it?

A: As a long-term program of management of the wastewater, what needs to be done is a more effective system of reuse of the water, the existing water.

In a normal operating reactor, water is continuously reused and used for cooling purposes, periodically cleaned, and it is those systems that are not working effectively right now in Japan.

In the long term, a program to release the water would be very damaging for the credibility of the Japanese.

There may be certain amounts that are allowed to be released within acceptable regulatory limits, and that is certainly a practice at an operating reactor. Some of it has low levels of contamination, and that is a practice that happens.

If it is within acceptable limits, then that is something that could be done.

Q: Is it possible to use lessons learned from the Three Mile Island accident and from the handling of old nuclear facilities, such as the Hanford Site?

A: The normal methods for reactor cooling, for filtering, for reusing water, those systems are not fully functioning at all with the reactors at the Fukushima plant. As a result, there is this need to continue to inject large quantities of water and then store the wastewater as it comes out.

I don’t believe that was the situation at Three Mile Island because there was not the damage to all of the water circulation systems.

Hanford and many other sites in the United States have more lessons because there were, perhaps, more similar issues with radioactive materials being put into tanks.

While it was a slightly different type of material, and liquid material, nonetheless, there were some very important lessons, like when you build tanks very quickly, those tanks may not be robust and last for a long period of time.

The other issue that is really relevant from those sites is just understanding the hydrogeology of the site, understanding how groundwater moves, what the impact from groundwater would be, how radionuclides will move through the groundwater, and ultimately how those processes work.

There is more to be learned from what happened at Hanford than the Three Mile Island accident at this point.

The Three Mile Island accident will become much more relevant when they get to the point of beginning to actually extract the fuel from the reactor vessels--or wherever it is--in the reactors.

The Hanford situation is a little bit different as a model because the activities that went on were government activities as part of the nuclear weapons program.

The issue of the water and the water contamination at the Fukushima plant is a very unique situation, and it does not offer any immediate examples of challenges.

Q: Many Japanese are opposed to the nation’s dependence on nuclear power plants. What do you think about the future of nuclear energy?

A: The current generation and type of reactors will always suffer from this fundamental challenge--the possibility of having some type of very catastrophic accident.

For a country like Japan, that is even more significant because of the small size of the country. When you have an accident, it has the potential to contaminate, as a percentage, a significant portion of Japan.

For the long term, it is beneficial to look for alternative ways to generate electricity.

As we look 30 to 40 to 50 years down the road, one would hope that we are generating electricity in ways that are more efficient and effective than the current generation of nuclear reactors.

And then, there is the potential for these catastrophic accidents. If I were advising the Japanese industry, I would look to put effort and focus on new technologies and new industries to generate electricity.

By SHIRO NAMEKATA/ Correspondent

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