Reply #4: Good point - definitely a possibility - that happened with the PBMR

[bananas]

http://www.nirs.org/factsheets/pbmrfactsheet.htm

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"INHERENTLY SAFE" GERMAN PBMR COVERS UP RADIATION ACCIDENT AND SHUTS DOWN

As Dr. Edward Teller, the father of the H-bomb said, "Sooner or later a fool will prove greater than the proof even in a foolproof system."

<snip>

In 1985, the experimental THTR-300 PBMR on the Ruhr in Hamm-Uentrop, Germany was also offered as accident proof--with the same promise of an indestructible carbon fuel cladding capable of retaining all generated radioactivity. Following the April 26, 1986 Chernobyl nuclear reactor accident and graphite fire in Ukraine, the West German government revealed that on May 4, the 300-megawatt PBMR at Hamm released radiation after one of its spherical fuel pebbles became lodged in the pipe feeding the fuel to the reactor. Operator actions during the event caused damage to the fuel cladding.

Radioactivity was released with the escaping helium and radioactive fallout was deposited as far as two kilometers from the reactor. The fallout in the region was high enough to initially be blamed on Chernobyl. Government officials were then alerted by scientists in Freiburg who reported that as much as 70 % of the region’s contamination was not of the type of radiation leaking hundreds of miles away in Ukraine. Dismayed by an attempt to conceal the reactor malfunction and confronted with mounting public pressure in light of the Chernobyl accident only days prior, the state ordered the reactor to close pending a design review.

<snip>

You just can't trust the nuclear industry.