A task of extraordinary delicacy and danger is about to begin at Japan’s Fukushima nuclear power station.
Engineers are preparing to extract the first of more than 1,000 nuclear fuel rods from one of the wrecked reactor buildings.
This is seen as an essential but risky step on the long road towards stabilising the site.
The fuel rods are currently in a precarious state in a storage pool in Unit 4.
This building was badly damaged by an explosion in March 2011 following the Great Tohoku earthquake and tsunami.
Moving the rods to safety is a high priority but has only become possible after months of repair work and planning.
One senior official told me: “It’s going to be very difficult but it has to happen.”
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A guiding principle of nuclear safety is that the fuel is kept underwater at all times – contact with the air risks overheating and triggering a release that could spread contamination.
So the operation to remove the rods will be painstaking.
A senior official in the Ministry of Economy, Trade and Industry (METI) told me that the rods will be lifted out in batches of 22 and in casks filled with water.
This will be done with a new crane, recently installed in the wrecked building, after the original one was destroyed.
The task of removing each batch will take 7-10 days, I understand.
Two critically important issues are whether the rods themselves are damaged and therefore likely to leak and whether the casks remain watertight to ensure the rods have no contact with the air.
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