22/11/2013 09:30
Fukushima’s most dangerous operation yields first successes
Workers at the Fukushima nuclear power plant have successfully removed the first nuclear fuel rods from a cooling pool suspended above ground in what is one of the most dangerous operations ever attempted in nuclear history, RT reported.
Already riddled with problems, the complex process of cleaning up and decommissioning the plant consists of many components. The removal of these rods is of paramount importance for safety and the prevention of another nuclear catastrophe.
Each fuel assembly contains 50 to 70 fuel rods – there are a total of 22 assemblies that have been transported today aboard a trailer to another, newer, storage pool on the final day of an operation that lasted four days, according to a statement by Tokyo Electric Power Co (TEPCO), Reuters reports.
What used to be done by computer will now be an entirely manual process, because of the tilted position of the cooling pools, which was affected by the tsunami and earthquake that battered the power plant in 2011.
The reason is that computers are programmed only to respond to the exact position of a fuel rod. With those positions now offset, the operation is a painstaking manual process. Each time the fuel rods rub together or are subjected to shaking, the workers risk unleashing incredible amounts of radiation.
There are more than 1,500 potentially damaged fuel assemblies located in Reactor No. 4 – the most unstable part of the power plant. It 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. Instead, hydrogen explosions blew the roof off the building and severely damaged the structure – a wholly different problem.
Now it is up to the cranes, controlled manually by workers, to do the job.
By TEPCO’s estimates, the reactor alone should take about a year to decommission, but some experts say even that may not be enough time.
And time is the one thing TEPCO may not have. Mini-earthquakes and tremors are frequent in the area, let alone big natural disasters. So with time and accuracy being important, many see the operation as a test of how well the plant operator can handle the entire decommissioning process.