Tuesday, April 19, 2011

19/04 TEPCO must provide more solid information on recovery from nuclear crisis


In this image released Saturday, April 16, 2011, by Tokyo Electric Power Co., top of the container of the nuclear reactor, painted in yellow, of Unit 4 at the Fukushima Dai-ichi Nuclear Plant is observed from its side with a T-Hawk drone Friday, April 15, 2011 in Okuma, Fukushima Prefecture, northeastern Japan. (AP Photo/Tokyo Electric Power Co.)
In this image released Saturday, April 16, 2011, by Tokyo Electric Power Co., top of the container of the nuclear reactor, painted in yellow, of Unit 4 at the Fukushima Dai-ichi Nuclear Plant is observed from its side with a T-Hawk drone Friday, April 15, 2011 in Okuma, Fukushima Prefecture, northeastern Japan. (AP Photo/Tokyo Electric Power Co.)
Layout of cooling systems at Fukushima No.1 Power Plant. (Mainichi)
Layout of cooling systems at Fukushima No.1 Power Plant. (Mainichi)

Just when will people be able to breathe a sigh of relief that the crisis at the Fukushima No. 1 Nuclear Power Plant is over? The lives of residents living around the plant are hanging on an answer to this question. For local farmers and businesses, it is a matter of life and death.

Tokyo Electric Power Co. (TEPCO)'s announcement of a schedule for bringing the disaster under control was significant. Unfortunately, however, the schedule lacks concrete details. Rather than serving as a plan to solve the crisis it is a display of just how many difficulties remain.

Radioactive materials continue to leak from the plant's reactors, but the source of the leaks and the exact times materials have leaked remain unclear. To control the leaks, the reactors must be cooled to under 100 degrees Celsius and stabilized -- a process known as a "cold shutdown."

TEPCO's schedule says it will take six to nine months for reactors to be brought to a cold shutdown. But when looking squarely at the schedule, it seems unlikely that the process will be completed within this time frame. A year is probably more realistic.

In this image released by Tokyo Electric Power Co., a radio-controlled PakBot robot opens a door inside the reactor building of Unit 2 as it is monitored with another Pakbot from behind during inspection of the tsunami-damaged facilities at the Fukushima Dai-ichi Nuclear Power Plant Monday, April 18, 2011 in Okuma, Fukushima Prefecture, northeastern Japan.
In this image released by Tokyo Electric Power Co., a radio-controlled PakBot robot opens a door inside the reactor building of Unit 2 as it is monitored with another Pakbot from behind during inspection of the tsunami-damaged facilities at the Fukushima Dai-ichi Nuclear Power Plant Monday, April 18, 2011 in Okuma, Fukushima Prefecture, northeastern Japan.

The power company says that it will first drench the containment vessels of the plant's No. 1 and 3 reactors -- including the pressure vessels -- in water. But if the containment vessels are damaged, water will leak out. Drenching the containment vessels in water is something that has not been done before when handling a nuclear power plant accident, and workers must be well aware of the strength of containment vessels.

But even if this first stage goes well, a cold shutdown will not immediately follow. Water must be circulated in a closed loop to continually remove heat from the nuclear fuel.

The containment vessel of the No. 2 reactor has almost certainly been damaged. Plans to patch up the damage have been drawn up, but radiation levels around the reactor must first be reduced. Because of this, it remains unclear if such work will actually be possible. And even if another device to continually remove heat from the fuel is built, unforeseen problems could occur.

TEPCO should form plans to address each of these issues while taking alternative solutions into consideration, and produce a concrete appraisal of the situation. In doing so, it is vital to confirm the state of damage to the nuclear reactors and pipes. Which parts are damaged and what is the extent of the damage? Workers may not be able to view every part up close, but TEPCO should provide solid information on each possibility.

Overall there has been a lack of information regarding the nuclear power plant. We still don't know the amount of radioactive materials that continue to leak from the power plant. TEPCO's schedule says it will expand and enhance its monitoring of radiation within three months, but the company should make an effort to speed this process up and do its job of releasing information. Otherwise, residents will find it difficult to draw up plans for their futures.

This Sunday, April 10, 2011 photo released by Tokyo Electric Power Co. (TEPCO) shows orange colored floats suspending
This Sunday, April 10, 2011 photo released by Tokyo Electric Power Co. (TEPCO) shows orange colored floats suspending"silt fence," that was installed under water to help prevent contaminated water from spreading outside the Fukushima Dai-ichi nuclear power plant's bay. (AP Photo/Tokyo Electric Power Co.)

The process of bringing a nuclear power plant accident under control must be measured in years, not months. The work to achieve a solution must be shared, and a system to handle the crisis over the long term must be developed. The release of detailed information will form the pillars of these efforts.

(Mainichi Japan) April 19, 2011


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