FUKUSHIMA – Signaling “the start of decommissioning in a real sense,” Tokyo Electric Power Co. says it is ready to begin removing nuclear fuel assemblies from the spent fuel pool of the reactor 4 building at its crippled Fukushima No. 1 nuclear plant in mid-November.
By the end of 2014, 1,533 nuclear fuel assemblies stored in the pool in the reactor building, partly destroyed by a hydrogen explosion amid the March 2011 meltdowns, will be transferred to a pool in common use at another building at the plant.
The reactor 4 building has the most fuel assemblies in its fuel pool: 1,331 spent and 202 unused.
On Wednesday, Tepco showed media the cranes and other equipment that will be used to transfer the fuel assemblies.
“Decommissioning work starts with fuel removal,” plant head Akira Ono said, adding that the fuel removal marks “the start of decommissioning in a real sense.”
Work to remove fuel from storage pools is scheduled to start in the second half of fiscal 2017 at reactors 1 and 2 and in the first half of fiscal 2015 at reactor 3, at the earliest.
Tepco aims to start removing melted fuel, whose location has yet to be pinpointed, from reactors in 2020. Technologies to locate the fuel are still in development.
In a process that will be repeated for about a year, 22 fuel assemblies will be placed in a container in the reactor 4 building pool and then carried to the common-use pool about 100 meters away after radioactive decontamination.
Tepco has covered the top of the reactor building to prevent the release of radioactive substances.
A Jiji Press reporter saw new fuel removal equipment installed over the pool on the fifth floor of the building. Debris around the pool has been cleared away.
At the time of the March 2011 mega-quake and tsunami impact, reactor 4 was offline for a regular check, with its fuel stored in the pool.
Unlike reactors 1, 2 and 3, unit 4 did not melt down. Many people, however, have voiced concern about the massive quantity of fuel stored in the damaged building.
IAEA observes testing
Two International Atomic Energy Agency experts began observing marine radiation monitoring activities Thursday off the coast of Fukushima Prefecture.
According to the IAEA, the experts are laying the groundwork for another IAEA mission later this month to review the process toward decommissioning the four severely damaged reactors at the Fukushima No. 1 nuclear complex.
With countries in the region concerned about the impact of radiation leaks from the crippled plant, the involvement of the U.N. nuclear watchdog in monitoring is expected to boost the credibility of the data Japan is releasing.
Hundreds of tanks have been set up at the plant to store the massive amounts of radioactive water produced as a result of continuing efforts to keep three of the damaged reactors cool.
But leaks have occurred frequently.
Groundwater flowing under the plant toward the ocean is also believed to be contaminated.
David Osborn, director of the IAEA Environment Laboratories in Monaco, and Hartmut Nies, head of the IAEA Radiometrics Laboratory, left Onahama port in the city of Iwaki at around 5:40 a.m. aboard the ship being used for water sampling by Tokyo Electric Power Co.
The ship is expected to take water samples at more than 10 points within 15 km of the Fukushima plant.
After observing the seawater sampling activity Thursday, the experts on Friday will visit a building at the power plant where water is analyzed.