We also need to cool the reactor and the spent fuel in the spent fuel pool but that basically means you wanna maintain the coolant inventory which means water in the primary system.

我们也需要冷却反应堆，还有乏燃料,在乏燃料池里，但是那基本上意味着,你们想要维持冷却剂存货,也就是在主系统中的水。

youdao

The conflicting information about the water levels in the pool storing the spent fuel rods in Reactor 4 is emblematic of the confusion the nuclear crisis has engendered.

自相矛盾的关于四号核反应堆贮存核燃料的冷却池剩余水量的的信息是这次核危机究竟带来多大危险这个谜题的标志。

youdao

Restarting cooling to the spent fuel pool at reactor 4 had been of particular urgency for Tepco as it had the highest number of fuel assemblies stored there, Kyodo news agency reported.

BBC: Power at Fukushima nuclear fuel ponds restored

All of the rods from the fuel core were put into the spent fuel pool above the reactor at that time.

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The key risk of storing spent fuel at reactor sites is radiation exposure from spent fuel that has caught fire when it is stored in a pool.

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