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First batch transferred to nearby pool

November 21, 2013



In start of long operation, Fukushima removes first fuel rods





The operator of Japan's wrecked Fukushima nuclear plant completed on Nov. 21 the removal of the first fuel rods from a cooling pool high up in a badly damaged reactor building, a rare success in the often fraught battle to control the site.

The batch of 22 unused fuel assemblies, which each contain 50-70 of the fuel rods, was transferred by a trailer to a safer storage pool, the last day of a four-day operation, Tokyo Electric Power Co. (TEPCO) said in a statement.

The company must carefully pluck more than 1,500 brittle and potentially damaged assemblies from the unstable reactor No.4., the early stages of a decommissioning process following the 2011 earthquake and tsunami that wrecked the site.

TEPCO estimates removing the damaged assemblies from reactor No.4 alone will take a year. Some experts say that timeline is ambitious.

Still, it is an urgent operation. They are being stored 18 meters (59 feet) above ground level in a building that has buckled and tilted and could collapse if another quake strikes.

Carefully plucking the damaged fuel assemblies from the reactor building is being seen as a test of TEPCO's ability to move ahead with decommissioning the whole facility--a task likely to cost tens of billions of dollars and take decades.

The removal has to be conducted under water. If the rods are exposed to air or if they break, huge amounts of radioactive gases could be released into the atmosphere. Each assembly weighs around 300 kg (660 pounds) and is 4.5 meters (15 feet) long.

The hazardous removal operation has been likened by Arnie Gundersen, a veteran U.S. nuclear engineer and director of Fairewinds Energy Education, to trying to pull cigarettes from a crushed pack.

TEPCO started the operation on Nov. 18, slowly pulling the assemblies out of the submerged racks by crane, before transferring them to a heavy steel cask, designed to shield workers from radiation during the operation. The cask was transported to a building housing the station's common pool, which TEPCO says wasn't damaged in the quake or tsunami, where they will be deposited.

TEPCO will review the process before starting the removal of the next batch, it said in a statement.

Extracting spent fuel from the plant's other reactors, where radiation levels are much higher because of core meltdowns, will be even more challenging.

TEPCO has floundered for more than two and half years with rising levels of contaminated water that comes from its jerry-rigged cooling system for the melted reactor cores, power failures and water leaks that have led the government to step in an take a more active role.




TEPCO transfers 1st batch of fuel rods from Fukushima No. 4 spent fuel pool



TOKYO (Kyodo) -- The operator of the crippled Fukushima Daiichi nuclear power plant on Thursday transferred the first batch of fuel rod assemblies taken from the No. 4 unit spent fuel pool to a different building that provides more stable storage conditions.

The move came three days after Tokyo Electric Power Co. started a yearlong mission to eventually remove over 1,000 fuel assemblies from the spent fuel pool of the damaged No. 4 reactor building to address one of the major hazards remaining at the disaster-stricken plant.

After filling a container with 22 unused fuel assemblies by Tuesday, workers on Thursday used a crane to lower the container from the fifth floor of the building housing the spent fuel pool to the ground about 32 meters below.

The container was then placed on a trailer and taken to a different building about 100 meters away. There is a pool inside the building.

The 2011 nuclear crisis began when the Nos. 1 to 4 units lost their cooling systems as huge quake-triggered tsunami waves knocked out most of the emergency diesel power generators at the site.

The No. 4 unit suffered a hydrogen explosion but avoided a reactor meltdown, unlike the Nos. 1 to 3 reactors. At the time, all of its fuel was stored in the spent fuel pool because the reactor was undergoing periodic maintenance work.


"Cask" containing fuel moved into safer pool




The operator of the Fukushima Daiichi power plant says it has removed the first batch of nuclear fuel from the reactor 4 building to a safer storage pool.

Footage released by Tokyo Electric Power Company on Thursday shows workers lowering a steel cask containing 22 unused fuel assemblies from the 5th floor of the reactor building. Engineers used a huge crane to lower the cask, 5.5 meters long and two meters across, onto a trailer on the ground.

The container was transferred slowly to a separate pool in a building 100 meters away, and lowered into water to store the fuel more safely.

TEPCO plans to begin on Friday plucking the fuel assemblies out of the cask and placing them in storage racks inside the pool. The utility says it will review the process before starting a second round of fuel transfer.

Thursday's transfer involved unused fuel units. The reactor's storage pool has 1,511 fuel assemblies left, including 1,331 highly radioactive spent fuel assemblies.

TEPCO says the building housing the separate pool can withstand an earthquake as strong as the March 2011 disaster that badly damaged the plant.

Nov. 21, 2013 - Updated 11:07 UTC




TEPCO moves cask from reactor building



The operator of the crippled Fukushima Daiichi nuclear power plant has moved a container, or cask, of nuclear fuel outside of the number 4 reactor building.

Workers just after 1 PM on Thursday moved the cask on a trailer to a separate storage pool 100 meters away.

The cask contains 22 assemblies of unused nuclear fuel rods.

This is the first load of fuel to be removed from the reactor building in the operation that started on Monday.

Of the 1,511 fuel assemblies remaining in the number 4 reactor building's pool, 1,331 contain highly radioactive spent fuel rods.

Plant operator Tokyo Electric Power Company says the building housing the separate pool can withstand an earthquake as strong as the March 2011 one.

TEPCO says the fuel can be stored more safely there than in the reactor building, which was heavily damaged in an explosion following the massive quake and tsunami.

The workers will now proceed to transfer the 22 fuel assemblies from the cask to the pool.

Nov. 21, 2013 - Updated 06:03 UTC

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