(...)
The CBS crew was able to watch the delicate and dangerous work of removing some of the 1,500 radioactive fuel rod assemblies. If the rods break, they could release more radioactive gases. (Emphasis Added)
There's an analogy that removing these rods is like removing a cigarette from a crushed pack.
"Take that analogy," TEPCO engineer Masayuki Ono said in Japanese, "and imagine that the cigarette in that box is lit."
Ono said they have removed 15 percent of the fuel from Reactor 4. But it will be far more difficult to retrieve fuel from the other three reactors that melted down. Those are so radioactive that the technology to dismantle them does not exist yet.
(Note: The cigarette pack reference refers to a quote from nuclear expert Arnie Gunderson who has surveyed the damaged plant in person. Here is an excerpt below from an article in Natural News from December 4,2013 that quotes Arnie Gunderson:
"Now, I used to build fuel racks, and the tolerances are very, very high precision," Gunderson said. "If the fuel is in them, and the rack is distorted, it becomes extraordinarily difficult to pull the fuel out. It's almost like a pack of cigarettes. You can pull the cigarette out easily unless you distort the pack, in which case it becomes really hard."
So, he continued, the problem facing engineers at Fukushima - particularly with reactor 4 - is major rack distortion.
At this point, the fuel rods which were the easiest to reach and pull out have been removed. But the job gets much more difficult from here on in.
He described a three-pronged problem.
"First off," he said, "these racks are no longer as designed. They've been beat up by sliding side to side in the earthquake. [Secondly,] they have rubble in the rack. The third piece had to do with the building."
Gunderson said the building housing reactor 4 was "structurally compromised. There was at least two, if not three, explosions in the building," leaving no "envelope over [the] top of the fuel pool."
In order to begin the process of removing the rods, Gunderson said TEPCO constructed a containment building and a sort of "esophagus" surrounding a crane system, so that removal can be effected without spreading radiation.
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