By Dr. Heather Johnstone
A huge explosion has occurred at the No.1 reactor of Japan’s Fukushima nuclear power plant following yesterday devastating earthquake, raising fears worldwide that a nuclear meltdown may occur.
Four people have been reported hurt in the explosion, but what is unclear at the moment is whether the integrity of the No. 1 reactor has been compromised.
From media images of the explosion it appears that at the very least the walls and ceiling of the building housing the reactor have been blown-out.
Quoting the Japanese nuclear safety commission, the Kyodo News agency said radioactive caesium had been detected near the site, with radioactivity levels rising 20-fold in the area surrounding the nuclear plant.
However, at the moment, parallels are being drawn more with the US’ Three Mile Island incident in the late 1970s rather than the 1986 Chernobyl disaster in the Ukraine; the effects of which are still felt today.
The 8.9 earthquake, the largest ever recorded in Japan, caused the power supply to the reactor water cooling system to fail. The situation was further compounded when the back-up diesel generators, which should have kicked-in immediately, also failed.
Yesterday, as a precautionary measure, the Fukushima nuclear plant was shutdown.
The operator has also been venting steam to control the pressure in the reactor, which has resulted in low-level, localized radiation.
A 60-km exclusion zone around the Fukushima nuclear plant has also put in place, with thousands of people either being moved or leaving of their own volition.
However, with the explosion it now appears that the authorities have been unable to stabilize the reactor cooling system.
There are also reported concerns over Fukushima No.2 reactor, which also suffered damage to its cooling system.
The International Atomic Energy Agency has said they are “urgently seeking more information”.