The term “China Syndrome” refers to a possible result of a catastrophic meltdown of a nuclear reactor. Also called a loss of coolant accident, the scenario begins when something causes the coolant level in a reactor vessel to drop, uncovering part-or all-of the fuel element assemblies. Even if the nuclear chain reaction has been stopped through use of control rods or other devices, the fuel continues to produce significant residual heat for a number of days due to further decay of fission products. If not properly cooled, the fuel assemblies may soften and melt, falling to the bottom of the reactor vessel. There, without neutron-absorbing control rods to prevent it, nuclear fission could resume but, in the absence of a neutron moderator, might not. Regardless, without adequate cooling, the temperature of the molten fuel could increase to the point where it melts through the structures containing it. Although many feel the radioactive slag would stop at or before the the underlying soil, such a series of events could release radioactive material into the atmosphere and ground, potentially causing damage to the local environment’s plant and animal life.
Some have less than seriously called this- ‘burning a hole all the way to China’ hence the name, but in fact it would probably go no farther than the mantle which is already kind of molten and radioactive or at worst the core of the Earth which is considerably molten and radioactive. Even in the absence of drag the Second Law of Thermodynamics would mitigate against it fully overcoming the force of Gravity and emerging on the other side, though you might want to buy some thick soled boots to be sure.
Of course they’re quite serious about that “release radioactive material into the atmosphere and ground, potentially causing damage to the local environment’s plant and animal life” thing.
Compare the above description with this-
Japan may have lost race to save nuclear reactor
Ian Sample, science correspondent, guardian.co.uk
Tuesday 29 March 2011 16.53 BST
Fukushima meltdown fears rise after radioactive core melts through vessel – but ‘no danger of Chernobyl-style catastrophe’
The radioactive core in a reactor at the crippled Fukushima nuclear power plant appears to have melted through the bottom of its containment vessel and on to a concrete floor, experts say, raising fears of a major release of radiation at the site.
At least part of the molten core, which includes melted fuel rods and zirconium alloy cladding, seemed to have sunk through the steel “lower head” of the pressure vessel around reactor two, Lahey said.
“The indications we have, from the reactor to radiation readings and the materials they are seeing, suggest that the core has melted through the bottom of the pressure vessel in unit two, and at least some of it is down on the floor of the drywell,” Lahey said. “I hope I am wrong, but that is certainly what the evidence is pointing towards.”
And about that radiation thing-
Radiation from Japan found in Concord snow
By DAVID BROOKS, Staff Writer, Nashua Telegraph
Tuesday, March 29, 2011
Radiation from the Japanese nuclear power plant leak has been found in snow in Concord at levels roughly similar to that found last week in Massachusetts rainwater – a level that officials say is 25 times below the level of concern even if found in water that people drink.