Accident at Second Japanese Nuclear Complex

The Japanese Nuclear Accident You Never Heard About

You’ve heard about the accident at the Fukushima Daiichi nuclear complex.

But there was another Japanese nuclear accident last year.

As I explained in March of last year:

The 6 problem reactors which have gotten all of the press are located within the Fukushima Daiichi complex.

However, the same nuclear power plant operator that runs the Daiichi complex – Tepco – runs a separate nuclear complex 7 miles away, called Fukushima Daini. There are 4 reactors located at the Daini complex.

On March 12th, Tepco reported:

Unit 1

- At 8:19am, there was an alarm indicating that one of the control rods
was not properly inserted, however, at 10:43am the alarm was automatically called off. Other control rods has been confirmed that they are fully inserted (reactor is in subcritical status)

***

- At 6:08PM, we announced the increase in reactor containment vessel
pressure, assumed to be due to leakage of reactor coolant. However, we
do not believe there is leakage of reactor coolant in the containment
vessel at this moment.

- At 5:22AM, the temperature of the suppression chamber exceeded 100
degrees. As the reactor pressure suppression function was lost, at 5:22AM,
it was determined that a specific incident stipulated in article 15,
clause 1 has occurred.

(Article 15, Clause 1 of Japan’s Act on Special Measures Concerning Nuclear Emergency Preparedness simply provides that there are elevated radiation levels or that “an event specified by a Cabinet Order as an event that indicates the occurrence of a nuclear emergency situation has occurred.”)

On March 14th, Reuters reported:

Tokyo Electric Power Co Inc said on Monday it had detected a rise in radiation levels at its Fukushima Daini nuclear power plant.

A company spokesman said that the cooling process at the plant has been working properly and that the rise was probably due to radiation leak at the nearby Fukushima Daiichi nuclear complex, where cooling functions were damaged by Friday’s massive earthquake and tsunami.

Today, Tepco announced that smoke was seen rising from Daini reactor number 1:

Smoke was spotted at another nuclear plant in northeastern Japan on Wednesday, Tokyo Electric Power Co. said.

The company said smoke was detected in the turbine building of reactor No. 1 at the Fukushima Daini nuclear power plant around 6 p.m. (5 a.m. ET).

Smoke could no longer be seen by around 7 p.m. (6 a.m. ET), a company spokesman told reporters.

Reuters noted in July:

The operator of Japan’s Fukushima Daini nuclear power plant, located near the tsunami-crippled Daiichi plant, on Thursday halted the cooling system at one of its reactors after electrical sparks were detected, Kyodo news agency reported.

But surely everything has been fixed at the Daini plant … otherwise we would have heard about it, right?

Unfortunately, Mainchi Daily News reports today:

The Nuclear and Industrial Safety Agency told Tokyo Electric Power Co. [Tepco] on Wednesday to prepare a report by the end of January on how to repair equipment at its Fukushima Daini nuclear power plant damaged by the March 2011 earthquake and tsunami, a senior agency official said.

The report is needed to “further ensure” the plant will remain in a stable state of cold shutdown, Kenji Matsuoka, chief of the disaster prevention section at the agency, said at a press conference, denying it is aimed at requiring the utility, known as TEPCO, to prepare for restarting the plant.

A cold shutdown is defined as a condition in which the bottom part of a reactor pressure vessel is kept below 100 C and exposure from the release of radioactive substances is being significantly contained.

The Fukushima Daini nuclear power plant was not so fatally damaged as the nearby Fukushima Daiichi plant by the magnitude-9.0 earthquake and subsequent tsunami. In December, the government lifted its declaration of a state of emergency at the Fukushima Daini plant.

But facilities at the plant, including the emergency power generator and the cooling system for spent nuclear fuel pools, have been damaged, according to the agency.

Of course, the “cold shutdown” label is a political – rather than scientific – one. As such, it is difficult to know how severe the problems at the Daini complex really are.

In fact, while it has gotten no mainstream news coverage, Tepco’s president apologized for the accident at Daini on November 4th and again on January 11th (Daini is also called “Fukushima II“).

And a professor emeritus at Tokyo University specializing in metallic materials science said last week that Daini’s containment vessel was damaged by the earthquake.

And Japan’s TBS News allegedly reported in June that 3,000 tons of radioactive water were sitting in the basements of the Daini nuclear complex.

Daini and Daiichi are not necessarily the only problem nuclear plants in Japan.  As Reuters noted in December:

Water containing radioactive materials leaked inside a nuclear power plant in southwestern Japan, but was contained and did not escape into the environment, the Nuclear and Industrial Safety Agency said on Saturday.

About 1.8 tonnes of water leaked from a pump at Kyushu Electric Power Co’s Genkai No.3 reactor on Friday, Tetsuya Saito, an official at the agency said.

The reactor has been closed since December last year for maintenance.

“The cause of the leakage is still unknown. Kyushu Electric is investigating now,” Saito said.

***

On Friday, Kyushu Electric issued a statement saying it had detected a rise in temperature at the base of one of the pumps which had triggered an alarm. But the statement did not refer to any leakage, although the company separately informed the nuclear agency about it, Saito said.

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  • Michael Antonelli

    In reference to “cold shutdown”, the definition is actually a reference to the operating modes defined in a nuclear power plant’s technical specifications.

    An example of which can be found linked in the PDF on the NRC website http://www.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr1433/r3/v1/

    Cold shutdown is defined on page 1.1-7. For a BWR plant it is known as “Mode 4″ or “Cold Shutdown” and comprises of the average reactor coolant temperature below 200 degrees F, signalling an end of boiling and steam production in the vessel. In the case of the Fukushima Daini complex, none of the cores have been breached and the reactor pressure vessels are intact. The units have been in cold shutdown, the technical operating definition, not the political one, since shortly after the Fukushima earthquake.

    This does not apply to the Fukushima Daiichi complex, as TEPCO has clearly stated that as the reactor core does not exist in its proper state at units 1,2, and 3, they are using modified ‘cold shutdown’ criteria.

  • jo6pac

    Hell what could go wrong and I’m sure we’ll be told the truth right;)
    What a nightmare for Japan and the rest of the world citizens. Brought to by greed.

 

 

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