Fukushima cleanup: extracting nuclear fuel rods from damaged reactors

Originally published on October 22, 2013

In mid-November, the Tokyo Electric Power company will begin extracting used nuclear fuel rods stored in one of the damaged reactors in the Fukushima Daiichi power plant.

Used fuel rods continue to emit heat and radiation, and need to be cooled for 3 to 5 years before they can be properly disposed. These rods are bundled, and stored in circulating pools within the reactors.

TEPCO is gearing up to extract 400 tons of spent fuel from reactor four. This will be accomplished by a 273-ton mobile crane that sits on a metal frame built adjacent to the reactor building. The structure is erected on a foundation separate from the building, and does not impose further strain to the reactor.

After debris is cleaned out from the cooling pools, the crane will extract the fuel rod bundles individually and place them into cooling chambers to be transported to pools in other reactors. This process is estimated to take up to 18 months.

1,533 used and unused fuel rod bundles are stored in reactor four's cooling pool, according to the Nuclear Regulation Authority. This amounts to 14,000 times the radiation released in the atomic bomb that struck Hiroshima in 1945.

Used fuel rods are still loaded with radioactivity. Dropping or damaging the bundles during the transfer process can trigger an explosion many times more severe than the one in March 2011.

Reactor four also contains 10 times more Cesium-147 than Chernobyl. Total withdrawal from the powerplant will be imposed in the event of an explosion, according to a Voice of America report.