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Decommissioning: Revision of road map

 June 12, 2015

Japan delays nuclear fuel removal schedule for Fukushima plant




The government approved on June 12 a revised 30- to 40-year road map to clean up the wrecked Fukushima No. 1 nuclear plant, but many questions remain.

The plan, endorsed by Cabinet members and officials, delays the start of a key initial step--the removal of spent fuel in storage pools at each of the three melted reactors--by up to three years due to earlier mishaps and safety problems at the plant.

This marks the second revision of the road map after it was last revised in June 2013. The government did not make changes to the overall goal to complete the decommissioning work in 30 to 40 years.

Three of the plant's six reactors melted following the 2011 earthquake and tsunami. The fourth, which was offline and had no fuel in the core at the time of the accident, suffered damage to its building, and its fuel storage pool was emptied late last year.

The plant operator, Tokyo Electric Power Co., has successfully removed 400 tons of spent fuel located in the upper floor of the No. 4 reactor building in a year long operation

Despite the delay, experts need to locate and study melted fuel inside the reactors and develop robots to start debris removal within six years as planned.

Experts believe melted fuel had breached the reactor cores and mostly fell to the bottom of the containment chambers, some possibly sinking into the concrete foundation.

TEPCO has conducted limited surveys of the reactors using remote-controlled robots.

The road map says the initial plan to repair damage in the containment chambers and fill them with water to conduct debris removal underwater is more technically challenging than previously thought, and alternative plans need to be studied.

Radiation levels at the reactors remain high and the plant is still hobbled by the massive amount of contaminated water.

The government also said on June 12 that it plans to revoke evacuation orders for most people forced from their homes by the Fukushima nuclear disaster within two years as part of a plan to cut compensation payouts and speed up reconstruction.

Thousands of Fukushima residents remain in temporary housing more than four years after the Great East Japan Earthquake and tsunami triggered meltdowns, explosions and radiation leaks at the Fukushima No. 1 plant.

Some areas have been opened, but many people are reluctant to return because of a lack of facilities and distrust of government claims it is safe. Others are resigned to never returning to their homes and businesses.

"My hometown is Futaba and I returned from Tokyo dreaming of reviving an industry" before Fukushima, said Takahisa Ogawa, 44, a beekeeper before the meltdowns.

"All that came to nothing because of the nuclear disaster," he said during a trial seeking compensation.

Futaba town is close to the plant and will not have its evacuation order lifted under the plan.

Prime Minister Shinzo Abe's government and the utility, bailed out by taxpayers in 2012, are undertaking an unprecedented cleanup to lower radiation levels in towns closest to the plant, although some areas will likely remain off limits for decades.

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Main points of the revised road map

- Completing measures against contaminated water by 2020. This will reduce the presence of contaminated water inside the reactors as well as the increase in contaminated water that is hampering the decommissioning work to almost zero.

- Reducing the overflow of water to the reactor buildings from the surrounding to below 100 cubic meters per day by March 2017. (new target)

- Halving the volume of radioactive materials in contaminated water inside the reactor buildings by March 2019. (new target)

- To decide a policy for removing melted nuclear debris from the three reactors in two years' time.

- Setting a method for removing melted debris from the No. 1 reactor in April-September 2018.

- Starting work to remove nuclear debris from the No. 1 reactor in 2021, delayed from its previous goal of 2020.

- Following is the new schedule for the start of work to remove spent nuclear fuel in cooling pools.

No.1 reactor: April 2020-March 2021

No.2 reactor: April 2020-March 2021

No.3 reactor: April 2017-March 2018

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