Nagata, Kazuaki. Water is both the savior and the bane at Fukushima No. 1 Japan Times http://www.japantimes.co.jp/news/2013/03/09/national/water-is-both-the-savior-and-the-bane-at-fukushima-no-1/#.UTof11eQPnd
[Excerpted]…The only progress Tepco seems to be making is on reactor 4, which was defueled prior to the crisis but had become a storage site for both fresh and spent-fuel rods — including some containing plutonium.
Experts believe the fuel rods in the spent-fuel pool of unit 4 present a critical risk and Tepco is working to remove them as quickly as possible before another major quake topples the remains of the building, which was heavily damaged by the hydrogen explosion.
...The pool, which sits above the reactor, contains 1,533 spent-fuel rods. Tepco plans to start removing them in November and hopes to be finished by the end of 2014.
Majia here: We know that spent fuel pool 4 burned at least once in March 2011 and many of us suspect that it burned further subsequently. Please see this post which contains images
Now the Japan Times is telling us that unit 4 contained plutonium fuel.
I'm pretty sure this is a new disclosure.
Was it MOX fuel, upon which unit 3 was operating?
Or was it some other kind of plutonium fuel? Where was it going to be used?
What is going on here?
PhillipUpNOrth commented at Enenews
MOX fuel is in the center rack of this old image of SFP4, majia. http://www.enviroreporter.com/2012/06/the-unforgettable-fire/all/1/
You can ID MOX by the different handle on top. Not the normal handle.
TEMCO had applied for permission to use MOX. So, they probably parked a charge of MOX in SFP4.
On spent fuel pool 4