Japan Update: Cooling Resumed at Reactors 4 & 5 at Fukushima (Some good news for a change - maybe)

Automated Trader ^ | 19 March, 2011

[Errant]

TOKYO (MNI) - Tokyo Electric Power Co (TEPCO) has succeeded Saturday in restarting an emergency diesel generator and resuming the cooling functions in Reactors 4 and 5 in its Fukushima nuclear power facility as work continued to bring power to the other reactors.

Reactors 4 and 5 at the plant are set away from the other four reactors, which sustained the most damage in the massive quake and tsunamis on March 11.

Meanwhile, workers have succeeded in attaching a power cable to the crisis-hit Fukushima nuclear power plant and are now working inside to ensure success when they switch on desperately needed cooling machinery.

"TEPCO has connected the external transmission line with the receiving point of the plant and confirmed that electricity can be supplied," the plant's operation, TEPCO said.

[catfish1957]

Bravo for the Japanese, my opinion of these people has tremendously went up after this whole event. No looting, robbing, no panic.

These are truly classy people, and sadly more civilizied than us Americans.

[a real Sheila]

Knowing what we know now, that the cooling pools are BONE DRY, and that the spent fuel rods are melting, this document is almost amusing to read! Actually it is very SAD to read because it shows the author of this document didn't know what he/she was talking about and this is going to cause great harm to a lot of people!



"Given that there is approximately 16 feet or more of water above the used fuel assemblies, operators would have ample time (days to weeks) to find another way to add water to the pools before the fuel would become exposed. For example, water could easily be added using a fire hose."

[a real Sheila]

spent fuel rods stored above reactor-

I read that storing them above made it very easy for the robotic system to remove the rods from the reactor and then place them into the pool.

They are now paying DEARLY for that convenience.

[CarryaBigStick]

Top of the pool is four floors up. The pool is forty-five feet deep, and normally sixteen feet of water covers the top of the spent fuel assemblies.

[CharlesWayneCT]

Four is actually in pretty good shape as well — it wasn’t running, and nothing is wrong with the core. The problem is solely the spent fuel rod pool, and they should be able to rebuild that and the walls around it, if they want.

On the other hand, that unit was also a very old unit, and they were exploring upgrading it.

[TYVets]

In the US spent fuel is placed in dry cask storage after five years. It would be even safer if the casks could be stored underground at places like Yucca Mountain

Thanks for correcting the incorrect information that I posted here on FR about spent fuel rods.

Does the figure of 14 years of circulating water around the fuel rods in the reactor at the time of the 3 Mile Island accident sound reasonable as to the amount of time required to cool "new" or "relatively new" fuel rods?

A side note about the politics of storing spent materials from nuclear plants.

Here in Missouri the Callaway Nuclear Power Plant went into operation in 1984. Before the plant came on line a petition drive was successfully made to place a proposition on the ballot for Missouri voters to decide if Callaway could operate BEFORE designated national safe storage sites were available.

2 to 3 months before election days polls said it was about 55% to 45% against opening the plant. A 10 to 20 million dollar media complain swung the vote to allow operation using on site storage. Money does win elections.

To me it is both sad and dangerous that the plant operators and others do not have safer storage sites available for spent nuclear materials. Common sense in national politics is a rare commodity and as you said "It is all political".

Again thanks for giving us correct information.

[J Aguilar]

-How are they going to remove the spent fuel rods from the pools with the current level of damage of the mechanized equipment?

It depends on the remaining level of radiactivity, but it would be easy to hoist a shielded container from the ground into the pool and then fill it with fuel rods using automatic equipment. That's no problem.

-How will the workers avoid contamination and acute radiation poisioning?

All sources of radiation should be blocked. Pools replenished (water acts as a shield), leaks repaired... remote operated equipment can be used, after a careful planning and workers should stay a short time in the plant until the situation improves. It is not difficult either if you have time to correctly asses the problems and plan the works it in advance.

-What type of clothing will protect them from high levels of radiation?

There won't be exposed: they'll stay in the facility a few hours, and radiation is not so high to damage anyone in such short time.

-How will they repair or remove the containment vessels and the fuel rods they contain?

The rods not heavily damaged, would simply be pulled to the upper pool and then transferred to a lower one or put into a shielded container, as in any other reactor, always keeping some feet of water between them and the workers. Others might be pulled out cutting the assemblies inside the reactor with remote equipment. The vessel is usually, even in healthy reactors, left for decades until the radiactivity decays. If the bottom still holds some fuel melted from the rods probably would need a special shielded container, but in any case and for all nuclear power stations, that is an issue that it is faced decades after the last shut down.