The mega-earthquake that struck northeastern Japan on March 11 has no precedent. The magnitude-9.0 temblor triggered devastating tsunami more than 10 meters high. No one had anticipated a disaster of these proportions.
It crippled the Fukushima No. 1 nuclear power plant and shattered assumptions that nuclear power generation is safe.
The credibility of Tokyo Electric Power Co. (TEPCO), operator of the plant, is in tatters.
Time and again, the Nuclear and Industrial Safety Agency (NISA), an arm of the Ministry of Economy, Trade and Industry, was unable to offer convincing explanations of the crisis that had enveloped the nuclear power plant. It prefaced every other statement with "according to TEPCO."
The agency conducted a thorough safety inspection of the plant in fiscal 2007. It must know all there is to know about the facility. Public confidence in the agency evaporated. This also was not foreseen.
So many unexpected events have taken place.
A magnitude-8.0 Tokai earthquake off Shizuoka Prefecture has long been predicted. If two other predicted earthquakes--Tonankai off Aichi and Mie prefectures and Nankai off the Kii Peninsula and Shikoku--coincide with the Tokai quake, it is assumed the magnitude would be in the range of 8.7, triggering tsunami of up to 10 meters.
What happened on March 11 was simply beyond the scope of these assumptions. Following the Great East Japan Earthquake, the information I wanted most was data about the shaking at the Fukushima nuclear power plant.
Shizuoka Prefecture is home to the Hamaoka nuclear power plant, operated by Chubu Electric Power Co. The plant is designed to withstand an earthquake generating a peak ground acceleration of 800 Gals and, in a worst-case scenario, up to 1,000 Gals.
An earthquake off Suruga Bay on Aug. 11, 2009, shook the No. 5 reactor at the Hamaoka nuclear power plant with a peak acceleration of 426 Gals, a reading more than twice as strong as those recorded at other reactors.
We are now working to identify the causes of these gaps in the intensity of ground shaking. When a major earthquake occurs, we pay special attention to the intensity of shaking recorded at any nuclear power plant that was affected.
But neither the NISA nor TEPCO has published much data on the intensities of shaking at the Fukushima No. 1 plant. The only facts that have been disclosed are that the peak ground accelerations at the No. 3 and No. 6 reactors reached 507 Gals and 431 Gals, respectively.
Why have they not revealed the figures for the remaining four reactors--Nos. 1, 2, 4 and 5? The trickle of information released by the agency and TEPCO has been very frustrating.
New safety guidelines needed
Among the host of unexpected problems that have occurred, the one that shocked me the most was the failure of the emergency diesel power generators--the backup system--due to the tsunami.
The safety of a nuclear power plant is guaranteed as long as its safety system functions properly in an accident, shutting down the operation, cooling the reactors and containing radioactivity within the facility as it is designed to do.
At the Fukushima nuclear power plant, however, the emergency power sources for the cooling system broke down. That essentially means the last line of defense against a nuclear disaster was breached.
What about the situation at the Hamaoka plant? I asked Chubu Electric Power what emergency power precautions it had taken.
Here's what the company told me: The emergency power generators are located in the first floor of the building. The room housing the generators is waterproof and has already been checked. No problems were found.
As a precautionary measure, two power generation vehicles for emergencies will be placed in an elevated area 25 meters above ground level.
As for the danger posed by huge tsunami, the company has said that the sand hill 10 to 15 meters high in front of the plant will serve as a breakwater in the event of tsunami.
But after the March 11 tsunami, the company decided to build a protective wall 12 meters high. I appreciate the company's quick action in response to the devastation caused by the towering tsunami.
The operators of nuclear power plants cannot escape responsibility for a nuclear accident by citing an unexpected turn of events. The safety of a system, not necessarily a nuclear power plant, can only be secured as long as the situation does not change radically beyond expectations.
A natural disaster on the scale that just struck Japan makes all earlier assumptions meaningless. That being the case, all assumptions should be reviewed.
The central government needs to swiftly develop new guidelines to ensure the operational safety of the country's nuclear power plants.
But creating new guidelines will not prevent unexpected events from taking place.
I believe mankind is incapable of controlling nature's fury. This is a tenet that most Japanese would accept, given that this country has experienced so many earthquakes, volcanic eruptions, typhoons and tsunami.
The Japanese government and electric power companies have been promoting nuclear power as a clean energy source that doesn't emit carbon dioxides. Now that the trust in the safety of nuclear power plants has been shaken, the government must fundamentally reconsider its energy policy and start taking steps to wean Japan from its dependence on nuclear power.
Chubu Electric Power plans to build a sixth reactor at the Hamaoka plant in Omaezaki, Shizuoka Prefecture, and start burning plutonium-uranium mixed oxide fuel at the No. 4 reactor. Given the current situation, these plans should not be approved.
Ignorance is a source of fear
Countermeasures have to be considered from both long- and short-term perspectives.
In the long term, we should make better use of renewable energy sources, especially solar power. One potentially good idea would be to install solar panels in abandoned farmland. Nearly 400,000 hectares of farmland remain uncultivated in Japan. In Shizuoka Prefecture, 12,000 hectares of farmland remain idle. These tracts of land, which used to be rice paddies and fields for crops, are blessed with abundant sunshine.
To become less dependent on electric utilities for power supply, every household should install a solar power generation system. All business offices should be required to install in-house power generation equipment.
Both businesses and households need to gain a certain degree of energy independence to make themselves less vulnerable to blackouts, planned or not.
Meanwhile, the most urgent short-term challenge is to deal with the current power shortage. The Fukushima No. 1 plant is clearly doomed to be scrapped. The earthquake brought a halt to operations of other nuclear and thermal power plants. As a result, the nation's power supply has dropped by nearly 20 million kilowatts.
It is not possible to halt all the nuclear reactors currently in operation. The power outages would be too severe.
At the Hamaoka plant, the 1.1-million-kilowatt No. 3 reactor has undergone a regular safety inspection and is now ready to resume operations. The safety inspection was based on guidelines that had been in place before the March 11 earthquake. If the reactor resumes operations, it will help ease the current power shortage.
Instead of the hard-landing approach of scrapping all nuclear power plants at once, we should adopt the soft-landing approach of gradually lessening the country's dependence on nuclear power generation.
There is also a great need to make both short-term and long-term efforts to sharply raise public awareness of the benefits, and the risks, of science and technology. Ignorance is a source of fear.
The Fukushima nuclear disaster occurred because of mistaken scientific forecasts and technological problems. Still, science and technology are the only way to overcome such problems. Switching to solar power also requires science and technology.
Expanding scientific knowledge and raising the level of technical expertise about disaster prevention will help to prevent groundless rumors from taking hold and lead to cool-headed responses to natural disasters.
The Shizuoka prefectural government has already started a program to promote science and technology and encourage practical research on disaster prevention.
(This article was compiled from an interview by Hiroyuki Ota.)
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Heita Kawakatsu is governor of Shizuoka Prefecture. After serving as a professor of comparative economic history at Waseda University's School of Political Science and Economics, he became president of the Shizuoka University of Art and Culture in 2007. He was elected as Shizuoka governor in July 2009.
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