Tuesday, 19 November 2013

Tepco starts rod removal

Fukushima operators begin risky nuclear fuel rod removal
In a highly risky undertaking Fukushima plant operators have finally begun removing over 1,500 nuclear fuel rods from one of the four reactors at its damaged nuclear power plant in northeastern Japan on Monday.



RT,
18 November, 2013

During the first transfers of the operation, steel fuel rods were laid in a cooling pool in a damaged reactor building. The portable pool holds 22 rods, with the operation being likened to removing cigarettes from a squashed pack. While the first group will take around two days to move, it could take up to a week to move the cooling pool to a common storage pool in a different building, TEPCO told Reuters.  "We will continue with the work from tomorrow and proceed, paying close attention to safety," said TEPCO in the statement.

It is important to conduct the transfer as soon as possible as they are being stored in an unstable building which could potentially collapse in the event of another earthquake. 


Unit 4 of the Fukushima Daiichi plant was offline at the time of the 2011 catastrophic earthquake and tsunami, which is why, unlike the other three, its core didn't go into meltdown. 


Hydrogen explosions blew the roof off the building and severely damaged the structure, however. Keeping so many fuel rods in a storage pool in the building poses a serious safety risk, experts say. 


With the help of robots and cranes, the workers will attempt to cautiously transfer 1,331 spent fuel rods and 202 new ones from the damaged reactor pool to a more reliable storage facility. If these rods break or overheat, radioactive gases could be released into the atmosphere, however, prompting a self-sustained nuclear chain reaction.
 

According to the operators of the plant, Tokyo Electric Power Co (TEPCO), all necessary measures have been taken to contain the threat stemming from the worst nuclear disaster since Chernobyl. 

This handout picture taken by Tokyo Electric Power Co (TEPCO) on November 18, 2013 shows a cask (C) of nuclear fuel being lifted and moved by TEPCO workers as TEPCO started operations to remove fuel rods from a pool at the unit four reactor building of TEPCO's Fukushima Dai-ichi nuclear plant in the town of Okuma in Fukushima prefecture (AFP Photo)

While the full decommissioning of the plant is expected to take decades, the company said it plans to remove 22 rods over the course of two days. A giant crane equipped with a remote- controlled pincer will be lowered into the pool and hook onto the rods, placing them inside a 91-ton cask which will be loaded on to a trailer and taken to a new storage pool. 


Earlier this week it was reported that three of the spent fuel assemblies that will be pulled from the nuclear plant on Monday were in fact damaged before the 2011 earthquake hit the facility. TEPCO said the damaged assemblies - 4.5 meter high racks with 50 to 70 rods of highly irradiated used fuel - wouldn’t be lifted from the plant’s Reactor No. 4, Reuters reported. 


In an 11-page information sheet released in August, TEPCO informed that one of the assemblies was actually damaged back in 1982, when it was bent out of shape during a transfer. 


Japan’s Nuclear Regulation Authority has assigned an inspector to keep an eye on the dangerous operation, as well as video monitoring of the removal site. 


Meanwhile, targets for reducing radiation levels and eradicating nuclear fallout in the areas still haven't been met, with the radius of evacuation after the Fukushima nuclear meltdown larger than the area of Hong Kong. Some areas will remain contaminated for years to come, experts say. Part of the cleanup plan is to decontaminate the surrounding towns and villages and follow new guidelines by the International Center for Radiological Protection. 


Nuclear expert inspecting the unit four reactor building of the crippled TEPCO's Fukushima Dai-ichi nuclear plant at Okuma town in Fukushima prefecture (AFP Photo / TEPCO)

Major setbacks have stalled TEPCO's handling of the crisis amid widespread criticism. The utility was scheduled to begin the clean-up operation earlier this month which had to be put off after the Japan Nuclear Energy Safety Organization pressed for further safety checks. 


A recent special investigation by Reuters has revealed the distressing conditions of working at the crippled Fukushima Daiichi plant, which are aggravated by very low pay and questionable attitudes to workers’ rights by sub-contractors involved in the numerous projects. 


TEPCO is in the process of decommissioning the entire six-reactor Fukushima Daiichi plant after three reactors suffered core meltdowns in March 2011. Moving the fuel assemblies in Reactor No. 4 remains the top priority, as their height above ground appears to be highly vulnerable to another earthquake. 

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