nuclear-news

Nuclear fuel pond contains entire fuel core of Fukushima Daiichi’s No 4 reactor

Nuclear update: Entire reactor core stored in fuel pond, New Scientist, 18 March 2011“…..Reliable, validated information is still lacking on water levels and temperatures at the spent fuel ponds, but the IAEA announced on Friday that prior to the earthquake,
The entire fuel core of reactor Unit 4 of the Fukushima Daiichi nuclear power plant had been unloaded from the reactor and placed in the spent fuel pond located in the reactor’s building.

This would explain the fear yesterday that the spent fuel in the Unit 4 pond could go critical. Meanwhile, the Tokyo Electric Power Company is continuing its attempts to restore electrical power to the plant. Electricity is urgently needed to run water pumps to cool the overheated reactors. Tepco says it expects that work to install power cables to units 1 and 2 should be finished on Saturday, according to  NHK. Power cables to reactors 3 and 4 should be installed by Sunday.

Fire engines and army helicopters have been deployed to dump tonnes of water on the plant to prevent it from overheating.

And there was another positive development on Friday, according to the IAEA: diesel generators are providing power for the cooling of units 5 and 6. The BBC, however, quotes the agency as saying that the battle to stabilise the plant is a race against the clock.

Wendy Zukerman, Asia-Pacific reporter

It’s not clear whether engineers at Japan’s beleaguered Fukushima nuclear power plant have laid a power cable to reactor 2. Currently, it seems unlikely that they have succeeded.

At 2154 GMT yesterday the BBC quoted a statement from the International Atomic Energy Agency (IAEA), saying that:
The cable had reached the site by 1730 local time (0830 GMT) on Thursday, and that engineers planned to reconnect power to the reactor once workers have finished spraying seawater over reactor 3.
The Tokyo Electric Power Company’s most recent plant update appeared at 1400 GMT, and made no mention of the cable.

According to this update, the level of reactor coolant had dropped and the reactor pressure was still increasing.

The power cable could restore power to the facility, allowing engineers to reactivate the pumps that send coolant through the reactors, and so refill the pools which contain spent fuel rods.

According to the Australian Broadcasting Corporation at 0300 GMT today, engineers were still “racing to restore” the cables:

“Preparatory work has so far not progressed as fast as we had hoped,” an official of plant operator Tokyo Electric Power Co (TEPCO) told a news briefing.
Short Sharp Science: Nuclear update: Entire reactor core stored in fuel po

March 19, 2011 - Posted by Christina Macpherson | general