nuclear-news

4 non-earthquake reasons to worry about Fukushima nuclear reactor no 4

4 reasons why we must be worried about reactor4 “other than earthquake” http://fukushima-diary.com/2012/12/column-4-reasons-why-we-must-be-worried-about-reactor4-other-than-earthquake/  by Iori Mochizuki   December 11th, 2012 ·   Now the biggest risk of Japan is reactor4.

However, we are only supposed to be worried about an “earthquake” to seriously damage the SFP of reactor4. Is this true ? No, it is not enough. We are missing 4 important facts.

1. It’s already deteriorating.
About one hour ago, Fukushima Diary reported the coolant system of SFP4 was stopped from 12/8 to 12/11. [Link] It is not known if the M7.4 of 12/7 affected.
Because of the warning, Tepco reinforced SFP4 by building a concrete base to support from the bottom of the pool.

However, if Mr. Murata is all correct, the concrete base is deteriorating, and the damage is on-going somewhere we can’t see. In that case, that would be really difficult to replace the concrete base anymore and all we could do is just to see it become unable to support the pool horizontally.
2. Ground is weakened.

According to Tepco’s survey map released on 12/11/2012 [Link], Tepco is still constructing on the east side of the reactor4 for ground improvement and land development. I was a civil engineer when I was in Japan. Whether it’s to build some additional facility or not, it means the ground was weakened that they must improve it. Weakened ground can cause further uneven settlement for unexpectedly small earthquake to tilt the reactor4 building.

3. Tepco’s plant parameter is a lie.

I was shocked at the news above because I thought I knew the state of the pool to an extent.

I check the plant parameters twice a day. According to the data, the temperature decreased from 12/1 to 12/11 by 2℃ and there was no significant change in the water level.

The accident proved the plant parameter means nothing. Also, none of the massmedia reported it knowing what was going on.

In case SFP4 falls down, we would know it after everything becomes too late.

4. It’s more vulnerable for Tsunami than before 311.

On 5/29/2012, Fukushima Diary reported reactor4 still remains frail for Tsunami. [Link] The Fukushima worker Happy11311 comments, “Tsunami guard remains the temporary state as well.”

Tepco published the report titled “Lessons learnt from the 311 earthquake and measures” on 10/12/2012.[Link] In this report, they mention the tsunami guard but it’s about Kashiwazaki Kariwa nuclear plant, not Fukushima plant.

In 311, Tepco lost all the power panels and emergency diesel generators because of Tsunami and coolant system was turned off.

Tepco states now SFP4 can resist an earthquake up to scale 6+, but that size of an earthquake will cause as large tsunami as 311 for 100%. This means they can resist the seismic shock to the pool but they’d have station/plant blackout again due to tsunami to come after the earthquake and tsunami might damage the crippled reactor building. They might say they can recover the power immediately, but tsunami keeps coming several times with continuous aftershocks. Roads will sink under the water.

Now SFP of reactor4 might be secure for earthquake, but it’s even more vulnerable for tsunami than before 311.

December 13, 2012 - Posted by Christina Macpherson | Fukushima 2012