The MOX plant is due to start producing reprocessed fuel for use in civilian reactors in 2017 or 2018.

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Existing stocks, former nukes and reprocessed fuel provide the rest.

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They were working in Reactor No. 3 which is of particular concern because it is the only unit to use MOX fuel, which is reprocessed spent fuel mixed with plutonium.

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Greenpeace activists tried, and failed, to stop a ship carrying reprocessed nuclear fuel through the Panama Canal .

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In February, BNFL admitted that staff checking the size of reprocessed Mox fuel pellets destined for Japan had faked safety records.

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When, in 1992, France (which also reprocesses commercially) returned to Japan the plutonium oxide extracted from reprocessed Japanese fuel, there was uproar.

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It is cheaper, vastly cheaper, to buy in your enriched fuel and then send it back out again to be reprocessed.

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During the decommissioning process, remaining fuel from the station's reactor will be removed and reprocessed.

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The fuel in No. 3 is a blend of plutonium and reprocessed uranium, referred to as MOX (for mixed oxide) and manufactured by the French nuclear company AREVA. MOX fuel rods are also less stable than plutonium-free rods.

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