Backlash from the reactor is likely to be an even bigger problem when the water inside the reactor is much more radioactive than usual and is under extremely high pressure.

当反应堆内的水比通常情况下的放射性高得多，而且处于高压之下的话，反应堆的强烈冲击可能会成为一个更加严重的问题。

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Most High Temperature Gas-Cooled Reactor (HTR) systems are significantly under - moderated for economic reasons, so that accidental water or steam ingress.

由于经济上的原因，大多数高温气冷堆(HTR)系统都是慢化不充分的。

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There was a moment when there existed the danger of a nuclear explosion, and they had to get the water out from under the reactor, so that a mixture of uranium and graphite wouldn't get into it with the water they would have formed a critical mass.

NPR: 'Voices of Chernobyl': Survivors' Stories

The water he drank was taken from puddles under two reactor buildings.

BBC: Japan MP Yasuhiro Sonoda drinks Fukushima water