Residents living near nuclear reactors in trouble after a massive earthquake and tsunami hit Japan could be driven from their homes indefinitely, but will not face the same disaster unleashed on Chernobyl in 1986, one local expert said yesterday.
“This is not, and will not be, Chernobyl under any stretch of the imagination. That’s good news,” said Lisbeth Gronlund, a senior scientist and co-director of the Global Security Program at the Cambridge-based Union of Concerned Scientists. “There was no containment vessel in Chernobyl.”
A blast after the 8.9-magnitude earthquake and tsunami threatened two reactor containers at the Fukushima Daiichi Nuclear Power Station yesterday. The first unit only suffered damage to the building that houses the reactor, said Japanese Chief Cabinet Secretary Yukio Edano, but the second was being watched closely after its cooling systems also failed.“Even if the fuel melts the whole reactor core, the fuel is enclosed in a steel vessel that is designed to be leak proof. Even if that is somehow breached, there is a concrete shell outside that,” Gronlund said.
She added the plant was not designed to withstand such a massive earthquake.
A nuclear meltdown occurs when a reactor’s cooling system fails, allowing the nuclear fuel to overheat and melt. If the container is damaged, the melting fuel could release radioactive substances into the air. Officials are using seawater to try to cool the nuclear core.
“It’s not been done before,” Gronlund said. “This probably will not be resolved for some time.”
Media reports estimated 170,000 people evacuated after the government issued a nuclear emergency order for residents living near the plant.
“Nobody is going near it,” Gronlund said. “They had an earthquake. Even if you don’t have an earthquake, you want to get people out of the area in case (the steel vessel and concrete shell) fail.”
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