Are Fukushima Reactors 5 and 6 In Trouble Also?

Are All 6 Fukushima Reactors In Trouble?

Everyone knows that Fukushima reactors 1-3 have melted down, and the fuel pool at reactor 4 is ruined.

But reactors 5 and 6 have been almost entirely ignored since the earthquake because – we were assured – the reactors were in controlled shutdown prior to the earthquake, and so all was safe.

However, there are rumors of problems.

For example, Fukushima Diary notes:

On Tepco’s press release data of 4/25/2011, Iodine-133 was measured at intake of reactor 5 and 6.

0.15 Bq/cm3 8:50 4/24/2011

0.23 Bq/cm3 14:30 4/24/2011

Also, according to press release data of 6/13/2011, the temperature of reactor 5 and 6 were hotter than 200 ºC, and data of 3/11~3/15 are concealed.


Even on 3/19/2011, they were still 183C and 167C.


5/16/2011, Tepco released data of how much contaminated water is sticked [I assume he means “stuck”] under the container vessels.

The table shows,

300 cubic meters under reactor 5,

13,500 cubic meters under reactor 6.



In the data on 6/13,the temperature of the water in container vessels are carefully concealed from 3/11~15

(See original for additional graphics; and see this).

Remember that reactors 5 and 6 have spent fuel pools as well as reactors. As I pointed out on March 16th:

Kyodo News notes:

Edano said water temperatures in the pools at the No. 5 and No. 6 reactors at the Fukushima plant have been rising as well.


The agency said among the three, the situation is the severest at the No. 4 reactor because all the fuel rods are stored in the pool due to the change of the reactor’s shroud. At the No. 5 and No. 6 reactors, up to one-third of the rods are being kept in the pools. The more fuel rods that are kept in a pool, the more radioactive substances could be emitted.

I noted on May 31st:

While most of the problems have been at reactors 1, 2 and 3 (which were all operating when the earthquake hit) and reactor 4 (where spent fuel rods have been leaking), there have also been problems at reactor number 5 as well. Specifically, as

NHK writes:

The operator of the damaged Fukushima Daiichi nuclear power plant says temperatures in the Number 5 reactor and its spent fuel storage pool have risen due to pump failure. The reactor has been in a state of cold shutdown.

Tokyo Electric Power Company says it found at 9 PM on Saturday that a pump bringing seawater to cooling equipment for the reactor and pool had stopped working.

TEPCO says temperatures have been rising since then.

And as the Institute of Nuclear Power Operations’ Special Report on the Nuclear Accident at the Fukushima Daiichi Nuclear Power Station, demonstrates, the whole story of a cold shutdown of reactors 5 and 6 may be questionable.

As summarized yesterday by EneNews:

  • “Four of the five emergency diesel generators on units 5 and 6 were inoperable after the tsunami”
  • “One air-cooled emergency diesel generator on Unit 6 continued to function and supplied electrical power to Unit 6, and later to Unit 5, to maintain cooling to the reactor and spent fuel pool.”
  • “Unit 5 had been shut down and in an outage since January 3, 2011. Fuel had been loaded into the reactor and the reactor pressure vessel (RPV) reassembled.”
  • “Unit 6 had been shut down and in an outage since August 14, 2010. Fuel had been loaded into the reactor and the RPV reassembled.”
  • “The Unit 6 air-cooled EDG and portions of the electrical distribution system survived the tsunami and were used to reestablish cold shutdown on units 5 and 6.”
  • “After the tsunami impacted the site, operators were able to use the 6B emergency diesel generator (EDG) to provide power to cooling systems for the Unit 6 spent fuel pool. After installing temporary cables, the 6B EDG [generator] provided power to Unit 5 spent fuel pool cooling.”

This post is not affirmatively making claims, but rather asking questions, to which we deserve answers … especially since Tepco has been covering up the scope and severity of the accident since day one.

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