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information about Fukushima published in English in Japanese media info publiée en anglais dans la presse japonaise

Decommissionning marred with uncertainties - to say the least

June 10, 2013


Major challenges ahead for decommissioning


The flexibility in the latest timetable reflects possible unforeseen factors that may hamper the overall removal process of spent nuclear fuel.

The entire decommissioning process of the reactors at the Fukushima Daiichi plant is marred with uncertainties.

Removing melted nuclear fuel remains one of the most daunting tasks of all, as it presents an unprecedentedly difficult undertaking.

The Three Mile Island nuclear power plant in the US experienced a meltdown in 1979, but the melted fuel remained within the reactor core.

In the Fukushima case, the melted fuel rods ate through the reactor cores.

TEPCO still does not know the exact position of the molten fuel in the containment vessels.

Experts say the safest way to extract the fuel rods is to fill the containment vessels with water to hold in the radiation. But the utility has yet to identify the exact damage to the containment vessels.

Development of new technologies, such as robots and remote-controlled TV cameras to monitor the reactor buildings, is also indispensable. The timetable for the decommissioning work largely hinges on when these technologies will become available.

The use of makeshift equipment at the plant has resulted in a series of technological failures and unpredicted problems that have hampered the cleanup efforts.

Jun. 10, 2013 - Updated 09:46 UTC



Roadmap to decommission Fukushima reactors



The Japanese government and Tokyo Electric Power Company have decided to accelerate the removal of spent fuel rods from 2 of the reactors at the Fukushima Daiichi nuclear power plant.

Government and TEPCO officials on Monday jointly released a revised timetable aimed at eventually decommissioning all 4 reactors at the plant damaged by the 2011 March 11th earthquake and tsunami.

The revisions reflect instructions made by the industry minister to speed up the removal of damaged fuel rods.

Multiple plans have been drawn up which will allow the removal procedures at the separate reactors to begin on different dates.

The quickest plan calls for the process to begin in the first half of fiscal 2020 at the No.1 and No.2 reactors. That's 18 months earlier than previously planned.

But depending on the speed of the decontamination work at the reactors and the installment of needed equipment, more plans have been presented.

At the latest the removal work is to begin in the latter half of fiscal 2022 at the No.1 reactor, and the first half of fiscal 2024 at the No.2 reactor.

The plan for the No.3 reactor remains unchanged, with the work to begin during the latter half of fiscal 2021, at the earliest.

But the decommissioning process remains marred with challenges, as 3 of 4 reactors suffered meltdowns.
High radiation levels at the reactors have made technical advances necessary in order to decommission them, such as improving robots that can be operated remotely.

The government and TEPCO plan to officially approve the timetables before the end of the month, after hearing from local governments.

Jun. 10, 2013 - Updated 09:45 UTC

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