While reactor 4 was shut down at the time the earthquake occurred, there is concern there and at the other reactors about the pools containing used or spent uranium fuel rods.

尽管4号反应堆在地震时已经关闭，乏燃料棒的贮存池仍然令人担忧。危机应对的关键仍在于冷却燃料和控制泄漏，要做的工作有很多。

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If these tests are successful, Khazaneh said, "then the next tests, with fuel rods containing enriched uranium, will take place near the end of 2009, " ISNA reported.

CNN: Iran to test nuclear power plant

The authority has also proposed moving other material called "exotics", which includes fuel containing highly-enriched uranium, from Dounreay to Sellafield at a later date.

BBC: Nuclear material moved by train from Scotland to England

What they failed to appreciate, and what the company failed to tell them, was that a fast-breeder uses fuel that has a 19% concentration of the fissile isotope of uranium, 235U. Ordinary nuclear reactors use fuel containing around 3% of the fissile isotope.

ECONOMIST: All over in a flash