Editer l'article Suivre ce blog Administration + Créer mon blog
Le blog de fukushima-is-still-news

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

What about Mt Fuji, by Akio Matsumura

Japan’s Fault: The Risks of Mt. Fuji’s Eruption and Nuclear Power


by Akio Matsumura


What if Mt. Fuji erupts? The question seems random and provocative, but it is one we should be asking.

The Great Tohoku Earthquake that caused the Fukushima nuclear power plants disaster in March 2011 has caused scientists to worry that Mt. Fuji could erupt in the next two years.


Scientists worry that Mt. Fuji, dormant for 300 years, is showing signs it will erupt in the near future. What does this mean for nuclear power safety?

Several indicators – increased pressure in the magma chamber, receding lake water levels nearby, cracks in the crust – signal that the volcano, dormant for 300 years, has been affected by recent seismic activity (Japan Today). A study released July 27 by the National Institute of Advanced Industrial Science and Technology in Japan concluded that Mt. Fuji has erupted 43 times in total over the past 2,000 years, the Yomiuri Shimbun reported.

There is a strong precedent for large earthquakes (>M9.0) causing volcanic eruptions within three years:

  • December 26, 2004 at Sumatra, Indonesia. Earthquake M9.2 –Talang Volcano erupted March 12, 2005. And Tangkuban Perahu at West Java, Indonesia erupted March 13, 2005.
  • March 27, 1964 at Alaska, USA. Earthquake M9.2 – Redoubt Volcano erupted January 24, 1966.
  • May 22, 1960 at Valdivia, Chile. Earthquake M9.5 – Cordon Caulle erupted May 24, 1960.


No one can predict with accuracy when an eruption will occur, but to ignore the possibility that an eruption might occur — whether in 1, 5, 20, or 100 years — is dangerous and irresponsible.

Some will argue that drawing attention to an unpredictable volcanic eruption near a nuclear plant – an unprecedented situation – is alarmist. I say it is responsible. Nuclear power is a reality, but so are earthquakes, eruptions, and other natural and human disasters. Governments and utility companies should be realistic about the possibility that 10- or 100-year disasters can cause major nuclear accidents. They should explain to citizens the risks they face in exchange for electricity. The nuclear debate to this point has been incomplete.

My great concern is that the government and scientists might say the eruption of Mt. Fuji is beyond prediction, just as they did regarding mega-earthquakes and tsunamis when constructing the Fukushima nuclear power plants. Especially because nuclear power plants are seated in the shadow of Japan’s iconic volcano.


Geological map of Mt. Fuji c.1968. During a large-scale eruption on the eastern slope around 50 A.D., lava reached as far as about 700 meters above sea level, which is near Gotemba, Shizuoka Prefecture, where many lodging facilities are located today. The new geological map, revised for the first time in 45 years, is scheduled to be completed this fiscal year and is expected to be incorporated into municipal evacuation plans. (Yomiuri Shimbun)

I am deeply worried about the Hamaoka Nuclear Power Plant located in Omaezaki city, Shizuoka Prefecture. On May 6, 2011, Prime Minister Naoto Kan requested the plant be shut down as an earthquake of M8.0 or higher is estimated to be 87 percent likely to hit the area within the next 30 years. As of today, the spent fuel rods should be kept in the pool for another three years or so.

One need not be a scientist to see that the explosion of steam, water, ash, and rock could cause a power loss to a nuclear power plant and disrupt the cooling system in the nuclear pressure and containment vessels. An eruption would continue to produce ash and rock for several weeks, possibly preventing emergency repairs.

I understand that the safest measure in the case of an incident is to remove the spent fuel rods in the pool, but it is a tedious and time-consuming process to remove them. And then the ultimate question: where do we put them? Has Japan considered how many nuclear power plants around Mt Fuji should be considered at risk? We should not underestimate that decommissioning a nuclear power plant takes about 50 years.


All nuclear reactors should be phased out, said former U.S. Nuclear Regulatory Commission Chairman Gregory Jaczko in April 2013. Dr. Gordon Edwards, a well respected nuclear expert, helped us explain:

“[Jaczko] has arrived at a very basic realization: every potentially dangerous machine should have an emergency “off” switch that shuts everything down completely. And nuclear power reactors don’t have one. So, he concludes, all power reactors should be phased out. But a nuclear power reactor cannot be turned off completely, no matter what the emergency may be. Talk about a design flaw! Imagine a car that can’t be stopped, or a fire that cannot be put out.”

Japan has already constructed 54 nuclear power plants; we cannot beat the probability of a bad combination of a natural disaster and nuclear materials forever.

The main lesson I’ve taken from the Fukushima accident is the permanence of nuclear power. Any nuclear accident, whether through human error, natural disaster, or terrorist attack, will leave us with radiation and other health risks for a minimum of several hundred years.

Japan should be honest with its citizens about the risks they face in exchange for electricity.



Partager cet article
Pour être informé des derniers articles, inscrivez vous :
Commenter cet article